Car-Hauler Peterbilt has WEIRD fuel system problems. Cat C15.

In this video we are trying to figure out why this carhauler has such weird fuel system problems.
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[@AdeptApe]

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[@landseaandairtransport1471]

Where’s you get those clear tubes is that from a kit

[@AdeptApe]

​@@landseaandairtransport1471 They are in a kit we have at work. No idea who made them though, they are handy.

[@OgGeneralPerchie]

@@AdeptApe Whats your take on seafoam? From my experience so far it's prevented clogging in my oil and fuel system on a 99 f250 7.3 powerstroke with 295k miles

[@CanopyFlyer150]

Mercury was formerly named hydrargyrum and its symbol on the periodic table is "Hg". Hence why the pressure gauge reads in inches of Hg. Silver is "Ag" (argentum), Gold is "Au" (aurum) etc. The symbols for elements on the Periodic table comes from the elements original names when they were discovered.

[@aussiebloke609]

As an addendum, I believe the name "hydrargyrum" is a portmanteau of the Greek words for water and silver - which makes sense on a purely descriptive level, but surprised me it wasn't from a Latin origin. 👍

[@NotJRB]

I was about to point out that Hg is how it's listed on the periodic table. To you point, the chemical symbol for sodium is Na. Also, what may make sense for one language may not make sense for another. For example, a quick internet search shows that the word for Mercury in German is Quecksilber.

[@GIGABACHI]

Thanks for clearing that up.👍

[@adamfpv8294]

Cool! It all makes sense now!

[@grahammaxwell544]

Came here to say this but you beat me to it.

[@GIGABACHI]

I love these "detective work" episodes, it's like watching House but with diesel trucks instead of humans patients. Looking forward to next episode of the red dumpster fire for closure.

[@rnreajr9184]

Hg is the symbol for the element Mercury, from the Greek hydrargyros (meaning 'water' and 'silver'). I'm always glad to add information that does nothing to solve the problem.

[@jofixit11]

The primary filter if installed on suction side of pump with tank lower than filter (most common setup) will never run full until filter is nearly plugged. Actually that specific davco setup you showed has a line on the top of clear housing that says to change filter when fuel reaches the line. But same thing happens on most suction filters or strainers depending on design, you just can't see it normally. Also the restriction on the new filter being slightly higher is normal especially with cat filters until the filter media has been in service for a few hours.

[@kennyhilton7229]

That isn’t the case with those metal cylinder style filers. They fill up. However, the cartridge style like the Davco DOES function the way that you described.

[@garyharrington5300]

I've worked on trucks since 87 ,never once seen a primary filter full

[@jarredlee-bland9247]

I got n14 and it's always full

[@brentpew4853]

I ran into this on a peterbilt same engine. Ended up being the fitting between the 2 fuel tanks that regulate the return fuel back evenly. It was a real head scratcher for sure. Stumped about 4 of us before I found it. I found it by putting the fuel return straight to the tank with a open hose and it made the fuel restriction gauge go up even higher 🤷🏻‍♂️

[@brentpew4853]

The fitting was basically returning “too much” fuel. New one certainly cured the issue

[@swaags]

@@brentpew4853 does that gauge basically read differential pressure from before and after the filter? so you needed a little more restriction on the return?

[@cheerdiver]

@@swaags It's called a manometer.

[@esbrasill]

Less restriction "somewhere else" means the total flow gets bigger, so unchanged filter restriction will cause more pressure across the filter

[@peteengard9966]

Check how crusty the hoses are. I have seen way too many hoses where the rubber insides have gotten hard and brittle. Actually had pieces of rock hard rubber jam up a 90 degree fitting.

[@carzkartz9080]

Huge fan of your channel and I'll be darned about the vapour bubbles. Learnt something amazing this morning. Near 30 yrs industry experience and I never knew that.

[@billmoran3812]

I’ve seen the partially filled filter and constant bubbles in the suction line before. Hadn’t heard about vapor bubbles, but that makes sense. I think that occurs more when the transfer pump is close to its maximum lift capability. I’ve had the problem of losing pump prime on generator installations where the day tank pump can’t lift the fuel from the storage tank. I solved that by putting an in tank submersible pump in the storage tank to force fuel up to the day tank.

[@jeriwollmann7366]

Pretty amazing learning in this one Josh. Thank you for the shout out. Cheers man

[@mgojich]

I would check the fuel tank breather. If it was bad it could cause a vacuum. Maybe next time take the fuel cap off and see if the bubbles go away.

[@AdeptApe]

Good suggestion. I did try that and no change. The restriction would be uniform before and after the filter housing if the tank was the problem, but it was only showing restriction at the filter housing and not before it.

[@Romuls753]

@@AdeptApe maybe something in the like near the filter housing?

[@Roger_Rabbit_Adventures]

​@@AdeptApe does that have anything to do with old fuel lines? Someone once told me the insides disintegrate over time

[@ClipSwitchFlashlights]

@@AdeptApe I had a head-scratcher fuel system issue this week too. Would be curious to see what is up with this one. Cool find on the vapor bubbles! I haven't done much testing with restriction gauges, but I wonder if any restriction before the primary fuel filter would be simply added or actually compounded by the filter? I mean, we're talking pressure drops even in the restriction world. So say you normally see 3 in HG restriction (1.5 psi reduction) after the filter when the inlet is supplied with 14.7 psi atmospheric. But now say you introduce a 2 in HG restriction before the filter. Your restriction after the filter will now at least be 5 in HG (3 + 2 ) or a 2.5 psi reduction. Would it create even more than 5 though (since lowered inlet pressure reduces how much volume can flow through the filter media for any given pressure drop)? Note: the restriction went up after the new relief spring because the pump was flowing more volume due to the increase in pressure.

[@thethomasj1795]

Yep, any time I have a sucking air issue the first thing I would do is take the fuel caps off. It's the simplest thing to do, and the most over looked and I did learn that the hard way.

[@aleesixstring]

More than likely it is a collapsed fuel suction line to the first filter base, or the breathers on top the tanks are plugged up and not allowing the air back into the fuel tank. Trucks that old usually have fuel lines that are internally collapsed or are coming apart and if you cut the filter apart, will find little black pieces of fuel line

[@ti4go]

The chemical symbol for Mercury is Hg. Mercury was named after the Roman god. Its chemical symbol (Hg) comes from hydrargyrum from the Greek word hydrargyros meaning 'water' and 'silver'

[@edwardwagner3543]

Adept Ape The problem with the air bubbles and a high fuel restriction on the Pete car hauler is a common Peterbilt problem, no matter what powerplant is being used. Try removing the fuel caps, then check fuel pressure and restriction guages? The common problem is that the fuel tank vent or vent hose is plugged up, or the fuel cap vent has excessive grime around the secondary vent, creating a vacuum on the fuel system.

[@cullenmiller8170]

What about the fuel lines themselves? I have had them come apart on the inside and created a rubber flap that would close of the fuel line partially.

[@sumduma55]

I had one where a paper towel or napkin was in thr fuel tank and parts of it got sucked into the fuel lines creating a very similar behavior. I think the reasons for thr bubbles after the filter housing is that it becomes a place for small micro bubbles from the vapor to consolidate. It's there before but not as visible until they merge at the filter housing. In my case, i looked into the tank and saw the paper towel in pieces in thr fuel. In your scenario, I bet it was a pain figuring out.

[@scottphillips9824]

THAT WAS MY THOUGHTS EXACTLY CULLIN..HAD THE SAME HAPPEN WITH A TRUCK

[@cheerdiver]

I've seen that condition on a brake line, effectively creating a 'check valve' to the caliper. Put on brakes, slight pull to the working side. Release, extreme pull to the damaged caliper hose side. Pressure would bleed off, but it was a serious hazard.

[@CarlosDieselElectric]

A bad ECM can reek havoc. Especially if you don’t have a test ECM. Glad you were able to get it fixed and back on the road. We don’t see too many CAT engines in So Cal.

[@billcovert3473]

About a year ago I sent you some plans to build a fuel system tester, of which you found very interesting. It was developed by one of those "greatest generation guys" in the 1960's in a Cummins shop. That tester makes short work of what this video is discussing. A few months later I did my own "service truck tour" one episode I showed the testers. Your viewers would find those testers beneficial as that tester deals with all fuel restriction and sucking air from inlet of fuel pump supply thru primary filter, hoses and fittings. I have removed a lot of primary filters and they are never full. Through 40 some years using that tester I have chased many "vapor bubbles" not knowing what you taught me here. Big Thanks!

[@stevemetz8415]

Would sure like to see this fuel system tester. Have a kta 1150 that I suspect is drawing in air. Steve.

[@Two_trucks]

From Google ", mercury's chemical symbol, Hg, derives from the Latin name for the element, hydrargyrum--literally, liquid silver." BTW love the Channel, Im always around CAT powered Equipment and Cat powered trucks being in the oilfield and refineries

[@ocd_garage]

was ab to say this 😊

[@noberet]

@@ocd_garage Ditto

[@jgreeneauto]

I have a c12 Lemon , Fault same problem for years , Cracked pickup tube , new tanks problem solved

[@kingjames8283]

I love the see through Davco filters because you can physically see the health of the filter element and know when to change it. Initially upon element change, the fuel level will be very low in the housing which is good and then as the filter element from bottom to top gets dirty and clogged, the fuel level rises to cleaner sections of the element and once it reaches the change element line, then you'll know to change it. All of my trucks over the past two decades had the Davco filter housing including the International I owned for 12-years and just sold in Sept'22. I've since moved to Middle Tennessee and got a company driver job in a Kenworth T880 tri-axle dump with X15 engine and it too has the Davco filter housing which I love. The FASS fuel-air separator for Class 8 engines is the only product I know of that removes entrained air bubbles from filter system and sends them back to the fuel tank which leaves a pure solid stream of fuel to the transfer pump and fuel injectors. They are $750 bucks and increase engine power once installed. The FASS fuel-air separator removes both air bubbles from the tanks and vapor air bubbles created in the filter housing.

[@charlesb4267]

I would have said too that the hoses from the tanks were restricting from internal collapsing or a foreign object in a fitting elbow or a tank vent issue but your gauge ( can you trust it ? ) was showing low vacuum on the suction side of the primary. Years back with a 3406E I was having issues with lack of fuel and a hard start if the unit sat over night and had mechanics suggesting replacing the old fuel lines, primary filter housing, the primer pump etc and with my luck none of that changed anything, then another mechanic said I bet its your fuel pump and that its sucking air past the drive shaft seal so I installed a new pump and not only did it repair my on going air in the fuel system issue but my restriction gauge went up somewhat ( still a perfectly fine reading though ) from what had been a very low vacuum reading which only went to show how worn out my pump was !. I have to wonder if that dash gauge is a little off and just reading a bit more than it should, never thought that increasing the pump pressure bypass would have caused much difference in vacuum, I've replace that spring on one truck and I didn't happen to notice any difference there, only that I bumped up my pressure to a max of close to 110 when its at full rpm under zero load which was the objective.

[@xlxyetixlx]

I worked on a Pete with a ISX in it about a month ago on a roadside service call that used that same filter housing, it would run for a minute or two then die. Filter would only fill up about half way. I had poured the fuel that was in the filter out and it was full of black slime and sediment....put on a new filter with fresh fuel in it....ran for a few minutes then died again.....pulled new filter and was already full of black slime and sediment..... customer ended up having to get towed .... pretty sure that they had a restriction in the line from the tank to the filter....told them to get the lines and tank cleaned and flushed when they got towed....fuel in the tank appeared pitch black...was hard to tell how dirty it really was with it being 1 in the morning on the side of the freeway

[@noberet]

On my 1996 Jeep XJ I finally started getting upstream O2 sensor overvolt code. Was shortly before, and after getting the heater code for the same sensor. Replaced the sensor and all the catalytic converter codes I'd been getting for 15+ years went away.

[@AmanuelChala]

Well come Josh!

[@KC3406e]

I think I’ve been sitting here 4 hours watching Josh’s videos.

[@B0RN2RACE100]

I’ll go with a internally collapsed fuel line between the fuel tank and filter housing.

[@982berti]

The primary filter also called fuel/water separator filter. They start working almost empty and they fill up by the time when they get slowly clogged. I haven't seen one being filled up on any trucks, only they were old and it was time to change them. You can see it if there is a bowl type clear plastic housing installed where you have the paper style filter inside. You can see it filling up by the time and if the fuel level reaches a certain hight inside the bowl, it's time to replace the filter. You can extend the service period if you install a filter that has a tap on the bottom (CAT doesn't have that style but e.g. Baldwin does) and you drain couple oz of fuel every 2 weeks. The bowl type housing has the tap on the bottom.

[@badgerpa9]

Mercury is hydrargyrum, latin for liquid silver I think. High school was a long, long time ago. Nice education on the vapor bubbles did not know that. Did you see that the tractor company Big Bud is building tractors again, or starting to build them and they are using CAT engine, trans and axles. Stay safe and healthy

[@jrbernal2267]

One thing not mentioned or I probably missed was the reason for the longer and smooth part on the updated base,which is it is meant for an extra seal inside that only CAT filters have. Well I have only seen it at least on CAT filters. but honestly I really dont notice any difference when I have had to use other brands for my primary filter.

[@realliferepair9285]

Not sure if you've ever run into this but I have found someone had put a check valve on the return side from the head,and I also found on a duel tank set up the "T" between the tanks was bad causing the restriction.those are a couple of odd ball issues I've run into over the years.

[@goddom]

Hg is the elemental symbol for mercury on the periodic table of elements and used to by known as hydrargyrum in greek - hence the HG.

[@ElkoCowboy888]

The increase in vacuum could just be the Cat fuel filters are High Efficiency and filter down to 2 micron so filter material is finer,harder to pull fuel thru.

[@B0RN2RACE100]

The primary filter should be 20 micros and secondary after the lift pump should be 2 microns

[@catchup4430]

I was a driver for pilot oil. The travel centers we had Peterbilt’s with the same fuel system set up with C 12s and that’s what we found is if you just put the filter on there it would only run half full what I did I would pre-fill the filters all the way to the top and I also run an O-ring on the filter and we never had any more trouble out of it as long as you pre-filled it and put that flat O-ring on the filter housing because those seat wells had a low power, grace and peace

[@joeziahbabb]

Didn't really think about aeration of the diesel in the tank causing vapor bubbles when it gets introduced to a vacuum, but that makes sense. Good to know.

[@troywagatha2621]

Never would have guessed Ecm! Good work sir.

[@travishinck3843]

I have a acert converted to single turbo. Regular cat fuel filter on the block, wire mesh cleanable canister filter on the frame rail. When I service the truck, that very same filter gauge runs higher then as the more miles I put on it the needle drops to 2 or 3

[@guyfranks4354]

Josh, Hg is the symbol for Mercury in the Periodic Table of Elements.

[@optimumhorse0799]

Mercury’s element symbol on the periodic table is HG. Thats why its in. HG

[@markm0000]

The first thing I did when I bought my semi truck was replace all the fuel lines. It's very cheap insurance.

[@wcvp]

12:59 as an electrical engineer I agree

[@garymichalak5379]

HG is the symbol for Mercury on the Periodic table. Good job with your videos!

[@blackhat1652]

I've been caught out chasing air in the fuel system before with the vapour and cavitation of the fuel on the suction side before, now I only check the return to tank for air. Not sure if you did, but always a good idea to check the pick-up in the tank for blockages also.

[@seanisthebomb117]

Check to see if the return line at the tank(s) has a ball valve, I had one once that was causing similar issues because the return valve was 3/4 closed restricting the overall flow of the system. You could also for quick testing take the fuel return line and put into a bucket.

[@johngoldsmith6629]

Hg is the symbol for Mercury, sometimes called liquid steel. I noticed your atom sensor was reading 13. Is that normal for your altitude location. I am close to sea level, so I am at 15 most of the time. As you well know the o-ring boss primary fuel filter base came out with the REGEN engine updates. Was not getting enough flow so D. W. at Cat designed a higher flow base. I always check for air in the fuel system, before primary, after primary, after the fuel transfer pump and before the cylinder head and between the head and return check. Maybe over kill, but I have an ideal of what is going on. Cavitation in the primary base is a known problem. Diesel fuel has 10 % air in it. When you take the primary fuel filter loose, the system has no check valve in it. So the fuel likes to siphon back to tank. I have taken the 75 lb return check apart and give the spring a little stretch to increase fuel psi. Agree the o-ring boss fittings are better as they allow you to align the fitting and not be limited over pipe thread. Had one that the base was on backwards, so the lines was reversed. You could drop the fuel hose in a bucket of fuel on the primary inlet and check for a change in restriction. You could have a imploded hose or something stuck in the suction side causing the restriction. Engine left the factory as a 475 HP, was modified to a 625 HP (ouch), set back to a 475 and then legally rerated to a 550. Wonder if ECM got corrupted during this process?

[@scottc4433]

I just had a finger tight pipe fitting on the inlet of a fuel filter on a c15 just the other day . Truck worked fine just didn’t like to start after 3 or 4 days of sitting .

[@midevolgamingvortex8844]

Work on 389 car haulers all the time, wheel lifts are your friend. Also don't fully trust those restriction gauges I've seen the pressure transducer read inaccurately.

[@haroldbenton979]

Rubber fuel lines over time will swell and restrict fuel flow especially with the ulsf diesel fuel sold nowadays. 30 years ago I lost track of the number of fuel pumps on Cummins Detroit and Caterpillar engines I had to change the seals on when the first lower sulphar diesel was introduced. We literally had sets for or Cummins and Detroits in the shop and I had the special tools needed to change the barrel seals out on 3406 A and B series pumps. The boss man's standard replacement repair was all fuel lines tank to engine and back all O rings in the pumps and lines when the original failed. We got everything done in less than 3 months for the fleet.

[@ronniewilliz153]

I had to replace the ecu on my mom's can 4x before I figured out there was two wires going to the fuel rail that had melted the protective case and it was shorting out, it ate three ecu's before I figured it out. Now it hasn't had a problem since then. Might wanna check for broken or melted wires. It was also causing over fueling.

[@Roger_Rabbit_Adventures]

We love your comments, especially the last one! 😂

[@bearbait2221]

Yep my guess is fuel tank breather or return hose clogged down stream at or in the tank. Or a restriction on the intake think of volume vs psi you have of pressure 100psi but this does not indicate flow just pressure. Thats my 2 cents :) luv ur stuff

[@johnclamshellsp1969]

Great videos always. Regarding the fuel bubble issue, it may be very possible to have a fractured tank sender draw tube or weld at the top of the fuel sender. from 1984 to 1986 GM station wagons (307 Olds engines or 305 Chevy engines), and Chevy 2500/3500 pickups with the 6.2 diesel, we saw this many times. We encountered rough running and odd idle issues. The test was to put a GM "J" tool (clear tube with fittings) between the tank and the engine and look for this exact issue. If yes, replace the fuel sender and tank sock, and tank seal. I know our world of machines is different, but that could be the issue.

[@GIGABACHI]

7:08 no bubbles going into the filter housing. I was thinking the same(bad in-tank fuel pickup) until that point.

[@donaldjrchappell6800]

Well Josh, your getting a lot of response about the mercury, thank you for the trivia knowledge. Seriously I love learning. Which brings me to the restriction and bubbles???, Could the line size or a fitting be causing them as vapor bubbles and/or the restriction level? As for the filter fill level. I worked at a Kenworth dealership and was told by old timer mechanics that a fuel filter only fills as it gets dirty and restricted. So when they would pull a filter if it was only filled halfway, they considered it ok. If it was full of fuel then it was plugged. I don't know this to be untrue, but,,,, I have been maintaining a small fleet of tow trucks with 3116/3126/c7's, and if one is running poorly, I'll pull the fuel filter at the engine, if I find it full, install a new one and it runs much better. If it's not full I always find something else as an issue. Like a red rag plugging the pick up tube in the tank. Go times. Please, as I said earlier, I am always ready to learn.

[@34boo]

As a gear nut,you could check if it has a cracked draw tube in the tank, or sucking in air from loose or bad fitting or a porous hose😀

[@baileysomers-gr6zl]

That darn fuel return splitter valve

[@edwarddavis507]

Yes, Hg is the chemical symbol for elemental Mercury. It’s safe to assume that when the symbol doesn’t seem to agree with the name of the element it is because the symbol is a carry over from the Latin or Greek terminology. But I am sure you remembered this after you made the video Josh. This was a very good diagnosis. It was nice to see an honest diagnosis that is exactly the path I would have followed even if it turned out a little strange. Everything you did was an improvement to the engine performance so that’s what matters. However, I was wondering if you were able to reprogram the ECM or if you had to replace it.

[@evanjordan22]

Peterbilt fuel tank pick ups are real bad about cracking. I always replace them with a new tank straw that you just slide inside the existing tank pick up with a new 90 degree fitting. Best way to test if a straw is bad is to cap off a fuel supply line at the tank one at a time and see if the primary fuel filter fills up.

[@tcmtech7515]

I have a 1997 Kenworth T-800 with the Cummins N14 that will run at zero fuel system suction under power but as soon as it goes to idle it kicks up to 5 Hg of suction and will often get to near 10 Hg if coasting against the engine.

[@Roger_Rabbit_Adventures]

😳

[@ase-diesel-tech9930]

Maybe could have run a clear hose from the filter inlet to a bucket of diesel to eliminate a restriction back to the tank. A less than full fuel filter to me is a vaccum created by restriction. At least that's what came to mind. Partially collapsed hose or rag in the fuel tank something like that. Love the videos by the way. Wish you worked on cummins more since we have like 900 in our fleet. 😂

[@paulpence8895]

You've seen Purple Rain that Ralphybilt drives right? That car hauler is just BAD ASS!!!

[@billmoran3812]

I can see where the higher pressure spring might cause a greater pressure drop through the primary filter. Increasing the transfer pump pressure may cause the fuel recirculating flow to increase, thereby pulling more fuel through the primary filter. Counterintuitive, I agree. But plausible I think.

[@rbwoodwork1890]

Don’t know about you but I hated working on those car carriers! So much stuff built around them! Redi mix trucks were next then RV Coaches!😁

[@sudd2685]

Dang those boots look good, thank you for your videos really enjoy watching.

[@mysock351C]

Since it’s pulling a vacuum, my thoughts would be that the tank is not venting properly, or there is something blocking the pickup or the lines feeding the transfer pump. Not a truck mechanic, but in cars stuff getting into the strainer is a major cause of restrictions, and it’s amazing what does get into a tank from the pump. I still have half a shop rag in the tank of my Camaro. Someone must’ve left it in the service station pump and it got pumped in with the fuel. So far it has not caused issues, and the tank is a real pain in the ass to pull in the early unibody cars.

[@asbestosfiber]

Hg is from hydrargyrum the Greek term for "silver water"

[@swaags]

i learn more from you than anyone on the internet. you look good as fuck with the new do and mustache man

[@garymcdonald6529]

Seen lots of bubbles on equipment with clear sediment bowls or running 1/2 empty, never figured it out, or cared because the machines were running properly. It’s like wtf and on to the next breakdown. FYI, on machines using banjo bolts they turn into inline fuel filters, pine needles, small rocks, fuzz, etc.

[@thetexorcist2235]

I just wait to see the destruction of the week involving locomotives. One day I’ll try to get a picture of some of the crazy stuff that comes to our shop

[@2dogsmowing]

You did the filters a day after my birthday. 😂

[@catchup4430]

I work part time as a petroleum driver for pilot oil. The travel centers we had the same problem with the C 12s running the same filter set up. We got a brand new truck and 03 and it had been in and out the shop more times than you can shake a stick at Because the fuel filter and the air bubbles Peterbilt cannot figure out what’s wrong with it I’m a retired mechanic and was just doing this for extra money being retired and I’m a big Cummins person. I know you like cat I like to drive a cat, but our 03D cab, it is ran horrible boss man agreed to let me see if I could fix it on one of the days when the truck one being used I went to Fleet pride about a Cummins filter mount the ones that run the O-rings and ran Cummins filters. I finished with it right about shift change, when the Night Shift was coming in and it was boss man’s truck, he always got the new ones he got in it and laughed because I put a Cummins parts on a caterpillar engine. He didn’t say anything until he got the truck loaded and it one of the terminals you have to come out Make a 90° and pull one hell of a hill to get out of the river bottom. He got on the interstate and got it aired out. He calls me at home and he tells me this truck has never run that good and you could put your hand on the filter with the hot fuel, and you could tell that the filter was full all the way to the top, we wound up changing out just the newer trucks cause we don’t keep them but a 500,000 miles so I think I did two more for him. Peterbilt wasn’t too happy when they serviced the truck and the caterpillar people wasn’t happy but like boss man told him down there in the shop, one day when they were complaining about it, he said you little bastards couldn’t fix the damn truck. I got the truck fixed and it runs fine now runs the way it supposed to. I looked at the cat filter mount. I couldn’t see anything wrong with it just like you I couldn’t see a crack in it I just don’t know why those filters will not fill up with diesel, we had one you could fill the filter up with diesel screwed on the mount take off and within a couple hours the filter was back down to half full grace and peace

[@Bearcats737]

Ive never seena suction filter full to the top. It's normal for them to run 1/2-2/3 full. My guess on the restriction is a hose is starting to collapse and the higher pressure spring is demanding more fuel through a partial collapsed or pinched line.

[@tehbald]

That’s a real hair puller there.

[@commenter5469]

ECM cooler got plugged. N14 were bad about check valves that screw in to ECM cooler getting the spider web looking restrictions in it.

[@MitzvosGolem1]

Black fungus slime in old tanks and storage facilities.. Ran into that on marine and gen sets Clogged restrictions on pick up tube in tanks . What is your opinion on rebuilt ECMs? I had CAT flash one and it still did not run correctly.

[@carlospastran3527]

I had a peterbilt with an ISX15 that kept sucking air. Found out pickup tube inside left tank was loose and sucking air. $80 dollar aftertreatment pick up tube fixed the problem.

[@Teezeboy]

I think there’s a restriction in or near the fuel tank…

[@GKsGS400]

Mercury was was formerly named hydrargyrum from the Greek words hydor (water) and argyros (silver).. Hence the HG

[@ahilltodieons]

Might I say you look absolutely debonair? You have me very envious of your mustache, good sir.

[@AdeptApe]

Thank you the Mask.

[@arcticfox5118]

.....so i just checked my pedal thanks to this because my truck has been acting up for a while. 72% on the floor. No bloody wonder my truck has been gutless for the last while. Sad thing is 3 pete dealers all missed it lol....stupid 1 million mile truck.

[@curtisc.6516]

Can you do a video on they clear hose set up would love a little more explanation on the set

[@georgegeorgepht]

They are a major pain to tow also cause the so low. I have home made ramps I winch them onto. Then put my t bar under the axel the strap it. But u can only go so high because the back 5th wheel plate will drag on the ground. Super pia to tow.

[@marty0715yt]

(or in Hg) Unit of atmospheric pressure used in the United States. The name comes from the use of mercurial barometers which equate the height of a column of mercury with air pressure. One inch of mercury is equivalent to 33.86 millibars or 25.40 millimeters. See barometric pressure. Plus mercury is tasty!

[@Guillotines_For_Globalists]

What does it taste like?

[@seanwalsh999]

@@Guillotines_For_Globalists He is trying to be funny, mercury poisoning is a thing.

[@yves8639]

HG is the code for Mercury on the table of elements…

[@davidhoffpauir2957]

Josh not sure if this would matter but I have seen some Pete trucks with #8 hoses and fittings from the tanks to the Tee above the transmission not sure if that would make the restriction gauge run higher than normal.

[@freedomfighter5095]

Mercury has a Latin name that I don’t wanna look up right now but it’s two words starting with those letters. It means silver water or silver liquid

[@fish3cats]

Some mobile fuelers will drag their nozzles thru the dirt and drop stones in the fuel tank so it gets pulled up in the lines

[@leor838]

HG is periodic table elements for Mercury😅

[@akharder658]

I’ve had issues on John Deere’s where the fuel filter housing develops almost invisible cracks and leads to starting and run ability problems.

[@LeewardStudios]

Mercury in Latin is hydrargyrum which literally translates as “liquid silver”. I think you’ll agree that it is an adept description. So when people started assigning symbols to elements mercury got Hg. Similar reason why lead is Pb, gold Au.

[@zavalaerafael]

Bro digging the haircut and mustache 👍🏻😎👍🏻

[@catchup4430]

If I remember correctly, pilot told me they had those trucks set at 425 horse and 1800 foot pounds of torque if I remember correctly

[@baileysomers-gr6zl]

Hey @adept ape, when the fuel return flow splitter valve begins to fail, other than the tanks not equalizing what are some other symptoms I can look for

[@jessebeiler5235]

Hi let me try to input on the fuel pressure spring upgrade versus primary suction vacuum Rising the new spring raised the fuel pressure which meant more fuel flow through the primary filter causing higher suction reading the other thing I saw in your video was the usual high number of 90° fittings for a 379 Pete fuel system they need to be eliminated and straight fittings used at all places and the hoses re-routed to the inlet to the pump the inlet fitting to the pump must be reamed out to a larger internal size also Be watchful of air leakage at the clear tubing connections I found a comparison of the two filter housing flow characteristics quite interesting also what is the part number of the larger primary filter if a customer has fuel flow issues I recommend going to the davco 382 or better yet an airdog I hope this response is not too long

[@thistruckerslife]

Had a bottle blocked intank fuel pick up. Took 5 shop visits before it was fixed

[@rat4spd]

Hydrargyrum, Latin name for mercury.

[@markm0000]

Nice haircut bro

[@johnnylightning1491]

It's interesting to me that the ECM just failed a little bit. Could it maybe be that some of the flash memory got corrupted. In my non-truck/automotive experience with computers they tend to fail catastrophically not just a little bit. Maybe vehicle computers are different.

[@carzkartz9080]

I get what you're saying but in automotive circles I have definitely seen many partial failures that are nearly undiagnosable unless you have an appropriate model computer bcm and fob to switch into it. Leading cause is corroded or lose solder joint's on the printed circuit. Cause one is from an introduced resistance which will either screw up the computers day or an intermittent open circuit or intermittent resistance at a solder joint will screw with your day so bad you want to drink the bar dry afterwards. On board diagnostics are the computer checking other components, the computer does not diagnose itself, hence why you will go round in circles. If a component with in the computer fails that's when it catastrophicly fails and is usually easier to identify.

[@Velkanis]

usually engine controllers in automotive and heavy industry tend to be redundant and parallelized in many of their functions and processing, thus sometimes corruption may not happen in the static memory since its checksum will throw an error, but instead in volatile side where no checksum will save you

[@Roger_Rabbit_Adventures]

​@@carzkartz9080 intermittent......intermittent

[@markm0000]

Vehicles move down the road and therefore can develop intermittent hardware faults that are only caused during a certain vibration frequency.

[@carzkartz9080]

​@Roger Osborn hehe oops

[@Ed-ip2sg]

Darn those sneaky ECM’s.

[@CUSTOMWORKS7.3PSD]

Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver and was formerly named hydrargyrum

[@soulthatcreates]

Waay back when, Mercury was known as Hydragyrum... Now you know :)

[@nickhugg8091]

Sometimes if you find a fix that doesn’t make sense you don’t question it and let the customer be happy 😅