1984 Mercedes-Benz 300SD W126 - Replace Oil Filter Housing Gasket and Oil Cooler Lines

#impalamansgarage1
In this video I go through the complete process of replacing the
oil filter housing gasket and oil cooler lines on our W126 OM617 5 cylinder
turbo diesel. Along the way we ran into a number of snags which
delayed progress but they are all documented here in the video. I also
replaced the injection pump rack damper pin (fuel injection
adjustment bolt). This really helped my engine's idle and idle-return
performance.
(Pardon my verbal gaffes in using "inches" and "mm" interchangeably)
Top 10 Tips and Notes for this video:
1) If either your oil filter housing gasket or cooler lines are leaking and the cooler lines have been on the car a very long time, just cut the lines out of the car before you loosen the the fittings with wrenches. Use a reciprocating saw.
2) Once the lines are cut near the filter housing, the housing can be removed. You can then remove the old flare nut fittings from the
housing while working off the car. I removed the compression fittings
from the filter housing, cleaned them, and reinstalled them
with some JB Weld as a thread locker. It's all in the video.
3) Be careful loosening the flare nut fittings at the cooler. Use
a 22mm wrench to hold onto the cooler while you loosen the flare nut
with your 27mm. Just use open ended wrenches. There is no
need in making or purchasing special flare nut wrenches.
4) The turbo oil line may not line up at the filter housing during
reassembly. I suspect this is due to the difference in gasket thickness.
Disconnect the turbo oil line at the air breather bracket and the
turbo to give yourself some room for adjustment. The turbo oil line is also
attached at the back of the engine but there is no need to loosen that one.
You can slide the line a little bit regardless.
5) It's probably best to disconnect the lower radiator hose
and drain the coolant. You will need to raise then engine farther
than you expect in order to snake the cooler lines through the engine compartment.
Raising the engine this far puts a strain on the lower radiator hose and the radiator
fitting. Remember, the radiator tank is plastic.
6) Attach the lower oil line at the filter housing first. Leave the
top one disconnected to keep it out of the way. Keep the two hold-down
brackets loosely attached during this to keep the lines in place but
yet give you enough slack to move things around a bit.
7) When reattaching the cooler lines at the cooler, hold onto the
steel part of the line with one hand and tighten the flare nut with the
other hand. This will keep the line form moving WITH the flare nut
when it starts getting tight. There is no need to hold the cooler with a
wrench while tightening.
8) You do not need to use a lot of torque to tighten the lines
at the housing or the cooler. Let the compression fittings do the work.
If it leaks a little, after you crank the engine, tighten it a little more.
You don't won't to over tighten these connections. Be careful.
9) Motor Mounts - Getting these to line up for reassembly can be a challenge. I discuss this how to get around this problem in the video.
10) If the injection pump rack damper pin is original to your car, replace it.
You'll be working in that area anyway. The new ones from Mercedes are upgraded with better springs. It will make your engine run and idle better.
Parts:
Qty 2 - Motor Mount Bolts: (Local Hardware Store)
12.9 Grade M10x1.5 Socket Cap Screw - 40mm UHL (40mm of threads under the head)
Upper oil cooler line - Cohline - 6171800582
www.rmeuropean.com/Products/6...
Lower oil cooler line - Merecedes - 617-180-01-82-MBZ
www.pelicanparts.com/More_Inf...
Mercedes Engine Oil Filter Flange Gasket - Reinz 6161840780
www.fcpeuro.com/products/merc...
Oil - Chevron Delo 400 SDE
www.walmart.com/ip/Chevron-De...
Filter - Mercedes Engine Oil Filter Kit - Mann 0001802509
Diesel Fuel Injector Pump Idle Adjuster Screw - Mercedes 0000742674
www.fcpeuro.com/products/merc...

[@7425park]

You are effing great! I have 2 1983 300SDs. Grew up driving a 1958 220D. I am a diesle man.

[@ImpalamansGarage]

Thanks!

[@ronnymb67]

It was pipe sealant. Mine were a blast to remove too. I considered blasting but I wound up cutting them off. I used Teflon tape rather than paste on the new ones. My engine mount bolts were the same too. Lots of 'colorful' language used that day...

[@ImpalamansGarage]

Misery loves company!

[@ronnymb67]

@@ImpalamansGarage Ask me about the time I spent nearly 4 hours on my back on a cold garage floor replacing the starter in my 72 LeMans with a Trans Am 400 in it. Turned out it was a brand new off-the-shelf dead battery the entire time. 🤣🤣

[@yousefkhalil8665]

I had a terrible time with this job as well, but my fittings were not fused together like yours, I just wasted my time modifying wrenches and the like when I should have just cut the old lines off. PITA job, but nothing compared to the turbo drain tube, which I'm in the middle of now. That's how I found your channel, your vid on the turbo drain was instructive, hopefully I will have it replaced this weekend. Love the 300SD videos keep them coming, great job on the channel! Also, I read all the main how-tos and no one said anything about removing the whole filter housing, seems like it made the job easier. Also seems like there are so many ways to do one job on this engine.

[@ImpalamansGarage]

Thank you!

[@MrJohnnyblazed]

I have been waiting for this video!! Going to try to watch it later tonight when I have time! I think I've done this job at least twice when I replace my injection pump (:

[@ImpalamansGarage]

Been working on this one for a while. lol..... What a monumental PITA.

[@MrJohnnyblazed]

@@ImpalamansGarage great job! Impalaman's Garage Impalaman's Garage Impalaman's Garage Impalaman's Garage Impalaman's Garage oil cooler lines, just no room to turn a wrench to get them off.. oil filter housing no room either... the "L" wrench... I remember seeing antifreeze start leaking once I raised my engine up up up... When I first installed those oil cooler lines I remember instructions reading "take off the oil cooler lines and then install them the same way you took them off" ( if it was only that simple!!) Haaaaa... Of course the air filter housing mounts broke, I'm not surei even have the "t" part any more? Haaaa true, mine has no rust because it's well oiled!! (: owning this old of a car knowing it leaks oil, I am always aware and checking my oil probably twice a month...

[@MrJohnnyblazed]

Check to make sure you have enough clearance that the power steering belt is not close to swiping that oil cooler line when your motor mounts are really worn out your engine settles dust causing that melt to get awful close to that oil cooler line.... I did a video I thought it was going to be simple just changing the motor mounts little did I realize it's settled so much it pushed through and made a hole in the frame of my car.... I had to get a steel plate and put holes in it I'm going to post that video pretty soon it actually happened on both of my 300sd

[@ImpalamansGarage]

@@MrJohnnyblazed My motor mounts look pretty good. I removed them and inspected them. But I'll keep an eye on them for future reference. Now you've got me paranoid again. LOL.....

[@MrJohnnyblazed]

@@ImpalamansGarage hindsight is always 20/20. And I as well putting parts back on because sometimes you just want to get the job done. But looking at it you probably could have changed the motor mounts? You could also do another video on how to change your motor mounts in say, 6 months or a year? Those motor mounts arn't that expensive probably $15 each, Maybe $20? I'll admit yours did look pretty good but for peace of mind maybe could have been changed.? I did like how you explained it I explained it similar in my video it's not like you're just going to lower a heavy heavy engine is going to sit perfectly where the bolts go. I think what I did is first secure the motor mount Loosely to the frame so I can wiggle like a loose tooth and then I finish by putting the 8 mm into the motor arm... mine were so destroyed my motor mounts that it actually put a hole in the frame which made for a very tough motor mount change if you look at the video and fast forward 4:48 ( you definitely don't want this to happen) regardless it was a great video and I enjoyed watching it!! kzbin.info/www/bejne/mISofJZofrCSnqs

[@lorenreyes2855]

Dang I can only imagine how I would do this job on the ground? Nice work!

[@ImpalamansGarage]

Not going to lie to you. This was a hard job. Would recommend you get the car on blocks safely before starting. Get all four wheels in the air.

[@zach359]

on my 83 SD the supply oil cooler line was so corroded to the oil cooler it ripped the fitting right off, luckily my dad is a damn good welder lol.

[@ImpalamansGarage]

Nice! I have a MIG but it will not do aluminum since it's a basic model. You need something with low enough amperage to weld aluminum. This project was really challenging.

[@RandySchartiger]

man I used to love working on cars, specifically muscle cars! I still hype up my truck a little a burn outs are still fun I just don't like working on them as much as I used to lol thought I'd check out your channel man it's cool! I watch finnegan and freiburger from roadkill a lot too.

[@ImpalamansGarage]

Oh man..... Watched Roadkill from the very first episode. They were doing what I always wanted to do..... go some place, shop for and buy a car that day and take it on a road trip. I do a little of my own guitar maintenance as well. Have a few acoustics and a few electric. I'm just a hack learning to play but it's tons of fun. First thing I did when I got my first one was take it apart and understand how it worked before learning to play it. LOL !

[@rb.867]

Great video!

[@ImpalamansGarage]

This is a lot of work. LOL.... keep that in mind.

[@kuldipdhak7972]

Complicated jobs but you done

[@jeffreydamher1703]

do you have to raise the engine to be able to replace the oil cooler lines? or can it be done without?

[@ImpalamansGarage]

It is absolutely required.

[@stephenmato8963]

Got a Toyota with a 617 in it running and driving…got some oil in the coolant, going to verify today that it’s not a head gasket related issue. Based on sounds and lack of overheating/burning coolant, I don’t think it’s hg related. Was wondering if a leaking oil cooler could allow this to happen on these motors? Should I even bother with new lines, or just get new lines going to a new cooler? Thanks

[@ImpalamansGarage]

A leaking head gasket would not necessarily create an over-heating condition. That is not always the case. The oil cooler and radiator are separate on these cars so the oil and coolant cannot mix there assuming you are running the stock setup.

[@jungletension2835]

85 300D the OEM lower cooler line isn't available for my car. But it is available for the 85 300sd in OEM what do you think? I tryto keep everything I replace Mercedes parts

[@ImpalamansGarage]

Recommend using the proper part for the 300D. Not the 300SD. There are differences and I think you will run into headaches. If you can't get a Mercedes OEM part, then I would buy the best quality after market part you can find. Partsgeek has them. The other option is to have a flexible line made with the proper ends by a nice custom shop somewhere.

[@johnknippers2029]

Very informative and I'll definitely be following your videos if I can get this car back online. I have a 1985 300 SD, was doing my first oilchange and find outthat it's been converted to a spin on filterand I'm having trouble finding the spin on. No numbers on the old filter... do you know anything about this?

[@ImpalamansGarage]

Take the old filter to the parts store and match it to another one they have in stock. Just open the card board boxes until you find one that works. I think you will find a lot of similarities. Measure your gasket size and measure the one on a new filter to ensure they match. Or if you know the part number or brand of filter housing you could call thw manufacturer.

[@steverandall5814]

Why is the air cleaner housing rolling in circles at idle?

[@noahholladay7010]

Hey what part of Alabama you from?

[@ImpalamansGarage]

Right in the middle!