Servicing a Vapour Separator Tank (VST)

In this video remove the vapour separator tank from a Mercury outboard to clean it and show how it works. I also use a fuel pressure gauge to test the high pressure pump while the boat is running. Problems with EFI fuel pressure are easy to identify using this tool, it is then a matter of finding the cause.
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[@charlessprigg1731]

Thank you so much for making this video. I am a first time efi boat motor owner, and after years of carburetors, I was scared by the vapor separator and high pressure fuel pump. Thanks to your video, I was able to disassemble, troubleshoot and reassemble my vapor separator with no drama. Thank you for taking the time to make these videos.

[@Riggs1955]

My 2004 Mercury 60 EFI 4 stroke was left on the river too long without running (that was on me). Wouldn't run but for a few seconds when it did catch. I changed the fuel out (which looked pretty bad even though I had used stabilizer) and then began tracing the fuel...found it made it through the low pressure fuel gauge. Flushed out the lines by leaving the line open and pumping into a jar. No success. That's when I got online and learned about the VST (didn't know it existed). Because the motor had run well last year and it would start and run for a few seconds...I figured the VST had to be the culprit. Searched Amazon and found a replacement pump with "gasket" (keep reading) that worked for up to 60hp EFI Mercs. Ordered it and tore down the VST based on this video (watched several, but this was the most informative). I was surprised not to find a lot of gunk - just bits - so figured it had to be the pump (good I bought the replacement). Cleaned everything up using carb cleaner. But when I went to reassemble - the replacement pump did not fit correctly (I had to force it into the top rubber seal, and it would not seat in the VST. Bummer. Note, the new pump appeared to be the same length, but the nipple was too wide, and the bottom just would not seat (BTW - my VST had an old style gasket, not a rubber gasket/seal). So, I searched the model # on the old pump and found it was a Walbro F50000104 (keep reading), so I figured I needed to order the part. Watched the video again paying particular interest in his discussion of the pump...could be seized from setting up? As I figured the pump was bad, I took it to bench to test it (just need 12 V) - nothing. But then I did what he suggested and reversed voltage back and forth - still nothing - but after doing that about 5 or 6 times, it sprung back to life. AWESOME. Reinstalled the pump back in the VST and the VST back in the boat. Didn't immediately start, but after pumping the bulb up a while, the pressure came back and voila - she started. Took her for a spin on the river....and now she's back working like a charm. Kudos and a HUGE THANK YOU to people like Dangar who take the time to help the rest of us! BIG THUMBS UP!

[@amymercurio4284]

Sir that was an extremely helpful video. My 2016 40hp Mercury was exhibited the same issues and your video provided me with the confidence to remove and clear VST tank myself. Thank you very much.

[@user-iq6no1yb2o]

This was by far the best video i have found on this! Thanks for your time and effort!

[@vonvoyage14]

Just starting to work on my Mercury 60hp efi outboard motor and your videos are a lot of help. Great detailed explanation and step by step instructions. Cheers!

[@signelengis]

Thanks Stu.. I started digging for fixes for my Merc today, and found one of your old videos. I watch your channel anyway. Fun to come back to one of these older videos for a fix. It is my low pressure pump OR the grey fuel hoses......

[@flatfoot]

Have the same VST type unit on my HPDI. Always wondered what was inside. I think you're the first person I've ever praised on youtube. Content, clarity & approach was outstanding.

[@DangarMarine]

Hi Simon, glad the video helped you find out what is going in there. Thanks for taking the time to comment. :)

[@Liveoutdoors321]

Great explanation. Appreciate you buying the parts to repair low pressure pump instead of just buying a whole new pump. Not always that common these days

[@PVS7Sports]

Awesome Video! I looked and watched several videos. This was exactly what I needed. We really like our Mercury 50hp EFI but had a similar issue as this motor. Watched the video and dove in. Thanks for the explanation and clear suggestions. I also replaced the Idle Air Control Valve(Solenoid). Thanks saved a bunch of time and money. I subscribed and will watch others.

[@blakeminer1040]

I know this video is 4 years old but it helped me take apart the VST and clean out the needle valve that was causing fuel to leak out of my motor!! Great video!

[@b1walsh]

Dangar Stu, ive watched a ton of your videos over the past year. Wanting to give you big applause for really knowing your stuff buddy. You rock! Of course I just smoked a high pressure merc efi pump and this was a big help seeing you service the vst on this motor. Many thanks!!

[@DangarMarine]

Thanks mate, glad you like the vids. Sorry to hear about your EFI pump...

[@melcase8153]

Your videos have saved my hundreds in repair cost. I lost the vst drain screw and having problems finding a replacement. but I also have the problem of losing fuel pressure, but only at startup. I replace the primer bulb, but I still have to prime it every morning. Even when fishing, if I stop for an hour trolling, I still have to pump.

[@ronaldcach2779]

Thank You for taking the mystery out of this fuel system, I did not know what was going on with it. Thanks Friend

[@srwade62]

This video is very well done. I have had two mechanics look at my motor and neither wanted to get into the VST. This video will give me confidence to try doing this myself. I need to find a fuel pressure gauge someplace, but think I can handle the rest of the tools. Thanks!

[@DangarMarine]

Thanks Steve. Those gauges are pretty common on eBay.

[@philedwards2213]

Brilliant video, so well explained. I drained mine and it looked fine. Pulled the VST apart and the dirt etc was amazing. I highly recommend draining it regularly. I replace the pump and cleaned out the cooler at the same time. I always flush the motor after each use, but the small feeds to the heat exchanger and VST had become blocked and corroded. I will disconnect them and flush them separately from now on. Finishing with a blow through with compressed air. Its a Suzuki DF70 motor, but similar to your demo.

[@AckBoater]

I just subscribed to your channel and find your videos extremely interesting and informative. I run a 115 hp Yamaha 4 stroke on my boat. I'm learning a lot from you. Thank you for sharing your knowledge.

[@DangarMarine]

Thanks Martin, great to hear the channel has been helping you. :)

[@mitchsmith1268]

You do an awesome job very detail and clear to understand

[@capefear3297]

Your video simplified the repair on my recently purchased used 25hp Merc EFI VST. The HP pump case was rusting , hence rust clogging the HP pump screen. Ordered a new HP pump today. The last owner must have used ethanol fuel for the pump to be so corroded. Subscribed and liked.Thanks.

[@Fireship1]

Great video Stu. I don't have a four stroke motor, but still enjoyed watching and learning!

[@DangarMarine]

Thanks mate, you never know when you are going to need a piece of knowledge! :)

[@citationjeff]

This is an excellent breakdown of the vst. Thanks so much!

[@DangarMarine]

Very welcome!

[@paulanderson388]

Great job...I didn't know what a VST was or what it did until this video.

[@DangarMarine]

Glad I could help!

[@apackwestbound5946]

Absolutely some of the best web content anywhere!

[@DangarMarine]

Thanks mate. :)

[@jim67]

This is the best video I have seen. Very detailed and educational.thank you sir

[@DangarMarine]

Glad it was helpful!

[@andyanaoutdoors2487]

Thankyou for this video. I have a 25efi merc. It's been dying when put in gear and also when I let off from a stretch of full throttle. Motor has sat most of its life. I'll drain it and see if it helps. If not I'll tear it apart.

[@TheDeuceRider]

Had the same problem, so took the VST apart on my 2006 -60hp Merc ( nice video - very easy to follow ), every thing was pretty clean, however when I pulled off the high pressure pump, the little black oval shaped rubber filter " housing" was missing the fine mesh screen on mine. Going to look at the low pressure pump next.

[@jackmonigatti211]

Hey mate, I’m having issues. Originally the motor would slowly stall from being on full revs. I gave it a service, and cleaned out the VST, however the motor won’t even start now. As the fella said in the video, it may be low pressure pump, so I’ll look at it next. How did yours turn out? Mines same model as yours

[@davidhanserd2598]

This is an excellent video ! Well this may get a little lengthly but may be worth the read if you have a Mercury 60 Hp four stroke EFI. I bought a 2013 boat with probably 25 hrs on the engine. Took it out once and cut it off and had problem starting it. Going fishing this year and it would not start. Called several shops and long lead times and none would provide appointment therefore, started searching you tube. First changed fuel out then fuel filter. I then went to low pressure fuel pump and removed the tube and turned engine over. Pump had flow so i then went to vapor separator tank and drained with the brass drain screw. Still would not run. So I then pulled the separator using this video and disassembled. I found two issues first the high pressure pump had no screen on plastic end and i discovered the fastener end of an orange tywrap inside the tank.. There was a strange substance probably the remaining portion lodged at the end of the high pressure pump. This separator had never been removes because it had the factory clamps on all the fuel lines. Cleaned everything including the fuel regulator and reassembled. Pumped the bulb and hit the start switch and started immediately. Hopes this helps anyone with starting issues

[@elnegronica]

Great video as always! Greetings from Uruguay

[@DangarMarine]

Thank you!

[@jeffshoemaker8828]

Great video. You just saved me over a thousand dollars. Thank you!!!

[@jonhall7897]

Hi thank you very much for the video I have a similar problem with my Mercruiser 60hp efi. Now I will check all from this very informative video.

[@dallinklein1396]

What was your problem and what was your fix?

[@jonhall7897]

@@dallinklein1396 fuel supply line internally collapsed.

[@toneystevens5023]

That's for posting. The previous owner took all that of my engine and rugged in a external regulator. I bought all the right stuff but had no idea where all the hoses went to.

[@shawnkeenan2576]

Would love to see a pic of this setup. Thought about doing this myself. Thanks

[@toneystevens5023]

@@shawnkeenan2576 Don't. Pit it back stock.

[@ronfazer2423]

I have seen another video on VST and yours is very good!

[@DangarMarine]

Thanks mate!

[@Sparty1966grad]

Thank you very much. Great help. And it's funny at 1:32 when you realize the part actually looks like an outboard minus the prop :)

[@skunkedagain]

Very clear and helpful. Thank you

[@randyspringston380]

Nice job, I have a2011 mercury 150 pro xs optimax and one of the fuel rails is hotter than the other. It doesn't won't to stay running

[@johnbolongo9978]

Great info and vid as usual.....thank-you for sharing.

[@DangarMarine]

Thanks John, you're welcome. :)

[@wingnut622]

Man you just save me some money, Thanks for the video, I found a lot of corrosion in my VST and it was running like crap if at all. No telling what the shop would of charged me.

[@DangarMarine]

You're welcome David, glad you found the problem. :)

[@williamsebestik5957]

Thanks Stu, just what I needed!

[@DangarMarine]

Glad to help!

[@TheNutzandBoltz]

Thanks for the post. Brilliant work.

[@DangarMarine]

Glad you enjoyed it

[@tonyliontis7537]

another great video, you deserve more subs

[@DangarMarine]

Thanks Tony!

[@ryancarroll8621]

Hey Dangar, Yeah i just wanted to say hey :) loving the vids especially the evinrude 150

[@DangarMarine]

Thanks Ryan, hopefully that Evinrude will be going back on the boat today. Video of that on the weekend.

[@Ceviche956]

Excellent video thanks

[@Showmethefish]

Great job.... couldn't have said it any better....

[@ve3xtr]

Great video. Judging from the amount of HP fuel pumps being sold on ebay, I gather they are the major cause engine starting problems. I suspect my issue IS the HP fuel pump as I have inspected the low pressure fuel pump and it appears fine. If I squeeze the fuel bulb my engine still dies. Which is the opposite to your video. I did remove the HP fuel pump and applied 12VDC and the pump made a squealing noise and seized up. Just waiting for my aftermarket fuel pump to arrive.

[@DangarMarine]

Definitely sounds like your onto the problem. Hopefully the part will arrive quickly!

[@ronaldhowell4146]

Thanks for this, mine is 60hp 2005 efi, been sitting little over 2 years plugs firing but want start hope this does the trick

[@stevemiller1037]

Ronald Howell hey bro did this work or did you need a new one? Mine won’t start either gives no fuel

[@ronaldhowell4146]

It worked and got mine running, old one was in bad shape, it went dead few times but it might still have some bad gas in the lines, it's been sitting up 2 or 3 years, I'm trying to work the kinks out.

[@brendanwalsh9106]

exellent clear and helpful vidio

[@coulterburnett6595]

You were so helpful thank you.... you save me lots of money mercury wanted 1000 dollars... I got it done for 40$

[@DangarMarine]

Fantastic!

[@theheilious]

You are my hero, dude!!! You just help me save my buddy's boating season from the crap situation of his boat sitting in some overpriced mechanic's yard for months on end! We had gas blowing out the overflow. I'm pretty sure it was a gummed up regulator screen and/or a stuck needle. I used Seafoam Deep Creep and carb cleaner and reassembled (thanks to your exquisite direction). She runs like a dream again and no overflow problems!!! Thanks again Stu!! ~2015 Merc 60hp OB EFI

[@DangarMarine]

Good news, glad to hear its up and running again. :)

[@Lando1214]

Awesome video! This actually got a boat running that I purchased from a friend. The motor is a mercury 60 efi. My problem was indeed that screen above the fuel pressure regulator inside the vst. It was completely clogged. Hey, did you ever make a video on removing the lower cowling on the motor that is in this video? I'm having a problem finding it. I of course did subscribe to your channel and have watched many of your informative videos! Awesome stuff! Thank you

[@30roundclipazine79]

Brilliant video. I have a 06 25 HP merc/tohatsu that needed the vst cleaned after the factory gray fuel line disentegrated inside and plugged the vst strainer. Also a 12 merc 60 efi just like the one in the video that would start bigging down on plane and not go over 4000 rpm. Sometimes stalled and restarted immediately with a hard primer bulb. I took the vst apart first and found hard black sediment on the vst screen that I cleaned and solved the problem. Looked like black rust but not magnetic. I bought the biat used from a buddy that used e10 furl and didnt use the biat a lot. When i bought it i drained the fuel from the onboard 26 gallon tank and have only ran rec 90 ever since. Im perplexed as to what the sediment is as tgere is no evident corrosion in the vst and the liner of the fuel lines look good. I was thinking maybe the in tank section of hise on the regulator? Have you ever seen debris like this on a vst screen? Thanks forbthe great videos!

[@gurkha184]

Great video

[@wunderbar2011]

The culprit, it seems, was the float needle. Thanks for in excellent vid.

[@MrRojas54]

Awesome content brother. Thanks for all the information. What’s in the spray can with the red lid?

[@greglake2457]

Outstanding sir. Thank you.

[@DangarMarine]

Very welcome

[@pitsmcgoo]

Another good reason to have a water separator. I can imagine the problems you have if the vst gets full of water.

[@DangarMarine]

Yeah, a water separator is a lot cheaper than a new high pressure pump, that's for sure!

[@bhamfire22]

Excellent job!!! Hoping this is what's wrong with my Mercury 4 stroke bigfoot 60. I was told to flush VST, clean pressure regulator and a bottle of quickleen in fuel.

[@bhamfire22]

The boat hasn't been started in 3 years up until this past summer. It's a friend's boat. I was told if I could get it running I could have it they don't have time anymore for it. 3 years ago it ran great and just had new injectors and plugs. But now when at full throttle it will not run at max rpm or speed. Every so often it will but once throttled down and back up it stops. Got a new fuel filter I'm going to instal along with cleaning vst

[@DangarMarine]

Cleaning out the fuel system is a great start, particularly if it has been sitting for a long time. I would also throw some new spark plugs in it etc Treat the start up like a major service.

[@lefty940]

great video i think i have the same set up on my yam 115 efi so i will clean the vst out on it as i did have a problem with water in the fuel last year but i didnt drain the vst just changed the fiters

[@DangarMarine]

Yes, this is a common setup on all modern EFI outboards. If you had water in the fuel I would definitely drain the VST.

[@lefty940]

Thanks Stu i will do that

[@lefty940]

Hi Stu i took your advice and cleaned my vst (tricky job on the yam 115 had to remove inlet manifold to get at the vst). Glad i did it the filter on the bottom of the pump was very dirty so i went the full hog and cleaned the fuel rail cleaned the injectors and put new filters in the injectors too. What a difference it has made the boat is going faster than it ever did before got loads more power now thanks to your videos

[@WillsGarage91]

Nice job Stu. We see issues with VST's as well here due to ethanol fuel..

[@DangarMarine]

Hey Will. Does the Ethanol fuel leave water traces or cause other problems with them?

[@danmuller2940]

I love your videos! You have the best marine repair channel that I have ever seen. Can you tell be about your solvent sprayer? I get one like it. Thanks, and keep the awesome videos coming.

[@DangarMarine]

Thanks Dan. That sprayer is from Wurth. www.ebay.com.au/itm/Wurth-Pump-Spray-Bottle-1L-suits-brake-cleaner-solvents-degreaser-tyre-shine-/151021962172

[@chadschlosser5683]

I think my fuel pump is giving me problems as well. I took it apart same as you did. When I hook direct power to the positive and negative posts on the pump it doesn’t do anything. Motor has been sitting for 5 years. I have it soaking in solution hopefully it is just gummed up

[@ronaldhowell4146]

Opened mine up today,exact same one but my pump was corroded from sitting few years,

[@vonvoyage14]

Hello! Thanks for the very informative video btw. I would just like to ask on how I can custom make a gasket for the VST since parts are very difficult in our area. It has already been deformed and would not seal completely. Thanks

[@Lando1214]

Awesome video! Just out of curiosity, how did you get to that bottom or lower 8mm bolt to remove the vst? What did you use?

[@Showmethefish]

Iv got one to do tomorrow just like it... good video before surgery.....lol....

[@ClemsonTiger2013]

Hi, am enjoying all your videos! Thank you! my outboard has automatic oil injection and as I was changing that oil to prep for the season, I spilled on my concrete floor and made a mess! Any tips to clean up mess? Thanks

[@DangarMarine]

You can get a degreaser from any auto stone that will help get that off. Let it soak from a bit then scrub it with a stiff bristled brush. Pressure washers do a great job of the final cleanup if you have access to one.

[@badlose1879]

Great vid! Before I tear into this job on my 2003 40hp Merc EFI 3-cyl (which I should probably do anyways), I was hoping you could help with a quick question: If my upper fuel filter always empties when I'm giving it throttle, would you be more likely to suspect the low fuel pressure pump, high fuel pressure pump, or air getting into the lines before that upper filter?

[@michaeljohn8905]

Always great vids from Dangar. 👍

[@DangarMarine]

Thanks Michael!

[@junebrooks665]

Great Vidio thank you very helpful

[@leviellyson8030]

Great video. I’ve replaced my low pressure pump now the vst is pumping fuel out of the overflow tube at the top, inside back tube that goes over the vst and back down by the starter then out of the cowling through a tip into the water. Not good! I can’t figure out why it’s doing this. Any ideas?

[@cfisher0803]

Just curious if you made the video for the lower cowling removal?

[@kenmoses8]

Great video. Just can’t find an answer as to why the pressure would stay so low at only 15psi (high press shradder pin).... Time to replace the pump?

[@matthewfontaine6865]

hey mate quick question , when refiitting will the low pressure pump fill the tank up enough on its own giving the high pressure pump wont have anything to pump as its been drained? i have an 02 50hp efi that has been a bugger and had found that the low pressure pump had not been doing its job i wish i had of seen your videos a long time ago haha very helpful thanks.

[@brianpinter8932]

Stu, I am having a vaopr lock issue with my 1987 50 hp Evinrude. Is there a way to add a vapor separtor, perhaps an inline filter with a separator? Thank you!

[@jeffperkins6514]

On my 2003 Mercury 40 hp efi the fuel pressure regulator is on the outside of the vst. Is there supposed to be a hose hooked to the outlet pipe on this fpr? There's nothing attached to the small pipe coming out. I was under the impression there should be vacuum applied to it. Thanks for the video.

[@louissparks2496]

Interesting, as usual.

[@DangarMarine]

Thanks Louis.

[@nickbread1247]

What does the hose coming off of the high pressure regulator on the vst go to? Pls help Dangar stu 🙏. I have a empty fitting on the bottom of the vst tank but didn't know if thats what it hooks to or not.

[@kerryscott2552]

nice engine kerry here i have one the same 3 weeks old my prop hase a slight woble would that matter

[@ryitgrl85]

I really enjoyed the video! Where can I get ones of those pressure gauges? Is there a particular size for the Schrader valve? Thanks

[@williamtorres5213]

The tube where the float needle enters... Can you blow air thru that tube or does it have some sort of filter in the 90 of that brass looking piece?

[@peteabdu9179]

AWesome video! What did you spray the VST with to clean it out? Is that some type of carb cleaner?

[@gluf1130]

So glad I found this video. Excellent information on servicing/cleaning the VST. I have been having issues with my Mercury Bigfoot which has the identical VST from what I can tell. My boat issue is it will not go over 4000 rpms for the most part but very rare it will start going the 5200 rpms it was going before for about a minute then go back to the 4000 rpms. I had opened up the VST before seeing this video and cleaned the VST with carb cleaner but did not tear it apart like you did. I did notice the VST strainer at the bottom had torn but did not see much debris and put it back on as is. Did not think the strainer would cause the low fuel pressure. Could you give me some ideas of what I might check with this issue? Should I tear apart the vst and look at the parts again as you have shown in video? Thanks for any help!

[@DangarMarine]

I would put a fuel pressure gauge on it first. If you are getting a good constant 40PSI of fuel pressure then it can't be your problem. If it does fluctuate / drop then yes, I would pull it apart and go all the filters.

[@jimbogasoline8559]

Great vid! Ive never owned or have much knowledge on the newer 4 strokes..but it seems as if that is todays version of a carb cleaning (the vst). Are the injectors easy to access and clean on these motors?

[@DangarMarine]

Yeah, the injectors are nice and easy to get to on this motor and most outboards. Unlike the Subaru ones I have to clean this week...

[@kamilbialous6903]

Still, I’ve got a 2006 Honda 225 that is surging/dropping rpm. I’ll be cruising at 3900rpm and it’ll slowly drop to 3200 and after a few seconds slowly come back to 3900. You figure wits the vts and low pressure fuel pump like you showed in the vid? Sometimes this happens at 1700rpm too.

[@Arkieman]

I have a 2019 Tohatsu MFS40. The motor idles fine an runs WOT fine. However, I began to smell gas and then saw the film of fuel on the water. Upon inspection, it is coming from the top of the VST. It's a pretty good stream. Would that sound like a stuck float/needle forcing too much fuel into the VST?

[@davidandkarencole]

Thanks!

[@DangarMarine]

You're welcome David and tanks for your support! :)

[@markolav7017]

Nice mate..

[@DangarMarine]

Thank you! :)

[@billjimmis6837]

This is an excellent video and gives me the confidence to tackle this job. I have the same engine and it's leaking fuel from the overflow tube. I can only assume that there's a problem with either the needle valve or the float in the VST.

[@1991kelo]

Bill Jimmis hey did this fix your problem. Mine is doing the same thing? Thanks Chris

[@angelf200]

@@1991kelo Mine too!! Did it help?

[@dougvanslyke7267]

Need help with a 2015 Evinrude etec 25hp. Pulled high pressure pump out of vst and pulled wires off and I see a little piece of metal with a kind of diode made into it and it is connecting to both terminals on top of fuel pump. Any idea why that’s there?

[@luizaraujo4800]

Oi amigo! 😁👍 Normalmente Quantos bar de pressão nessa bomba injetora? Hi friend! ask me a question please! normally How many bar pressure on this injection pump?

[@KidBako]

Wonderful video - thank you! The issue you explain is very timely to my situationI. My new to me 2018 Mercury 40 hp 4 stroke EFI recently experienced fuel starvation issues. This came after running the boat over five hours and all was well. This was my third trip out since purchasing the boat. About a half mile from the launch ramp, the engine began sputtering and stopped. I immediately remembered I had not opened the small air vent on top of the fuel tank cap. The 6 gal. plastic tank sides were severely imploded and when the vent cap was opened, the tank regained its shape. I mention this because now the engine will only run a brief time after fully priming with the fuel bulb. I replaced the fuel filter and the fuel lines from the tank to the engine, but this did not help. Would I be correct the closed vent cap placed enough strain on the fuel pump to make it fail? Any guidance will be greatly appreciated. Thanks again for your video. Just subscribed!

[@DangarMarine]

I can't say I've heard of it damaging the low pressure pump, but it is possible. If priming with the bulb makes it run for a while it does sound like a pump problem.

[@b1walsh]

I have a question for you Stu; Are you aware if these Mercu-hatsu's have constant 12v to the EFI/HP fuel pump or if the ECU ramps the pump speed up and down depending upon demand? I have a recurring issue with an ECU on a 30hp EFI. Trying to decide if I purchase ECU #3 or if I find an ignition circuit to power the pump and move on... I realize there is a pressure regulator at the top of the VST and my assumption is that the pump must run full on and rely on the regulator to meter the pressure to the fuel rail.

[@deere3321]

Great explanation. I had no idea there was so much going on in a VST. I drained mine for winter on a 2017 Yamaha F70 and had to do a lot of cranking in the spring to get it started. Once it started, it ran fine. Any tips for getting it to start better after draining? BTW, I use ONLY ethanol free fuel.

[@DangarMarine]

You should be able to use the primer bulb to fill the VST. Sometimes you need to open a fuel line after the VST to let the air out though.

[@HomeroFB]

Hola tengo un mercury efi 60hp, y al encenderlo tira nafta hacia el exterior por el caño que sale de la válvula reguladora, tiene idea porque se pasa de precion o si será solo la válvula que este fallando?

[@LifesAdventures555]

Do you have a video on the VST for a 115 Evinrude? I need to find out how it works badly. Appreciate your videos. Thanks!

[@DangarMarine]

No I don't, sorry.

[@johnkuhrt9627]

Very helpful, I would have a new rubber gasket on hand before you take this apart.

[@DriveWayMafia]

I have a Yamaha t60 tlr 4 stroke it idles great revs great in neutral but under any load it’s bogging and stuttering please help !

[@whodgson82]

I am working on 2015 60hp bigfoot set for 5 yrs. there is no line coming out the top of vapor separator would that go to other side because it looks like it needs a hose connected there and I'm not getting any fuel

[@xlandscaper]

If you ever come across a Yamaha F115 that needs a vst service could you please make a video of that? Much appreciated, love your channel

[@DangarMarine]

Will do!

[@robsheffield4371]

I have a 02 40 4stroke EFI, bad running, fuel pressure is high, 60psi ? regulator ? line ?

[@matthewkehoe8502]

If the needle is damage or the float blocked such that the needle doesn't seat correctly, where does the fuel overflow to? I've noticed this issue on my own boat where fuel seems to be bypassing out through a port in the bottom cowl, but I haven't found any information regarding where the overflow is coming from, other than it is likely related to the needle

[@angelf200]

My engine is a 2005 Mercury four stoke bigfoot EFI 60 and I have gas spraying out from underneath the engine. Looks like the fuel relief valve. (white hole underneeth) What could it be? VST?