I learn more on KZfaq than I did in school. Thanks for that awesome explanation on how that basically works. I just had that replaced on my 2015 ETEC. Cheers!

That float lets vapor out while the separator is filling and returns the vapor to the block. It does not regulate fuel other then making space for it

That sure was a solid hit to the intake, gosh it’s lucky it didn’t rip the whole motor off lol. Good work getting it diagnosed and repaired.

The VST on Etec's contains a spring regulated fuel presure regulator on the return line coming back from the injectors it holds the presure at 25 to 30 psi , this returen line has its own tiny filter on it and it can cause a real headache when it clogs , as the returing trying to flow through this small return line filer backs up behind the cloged filer and it pushes the fuel presure in the injector fuel loop into a much higher presure then it should be , this puts a lot of stress on the electric fuel pump and also becuase the presure is to high it throws off the fuel delivery systems calibration making the motor run rich ,, make sure to check this filter if the presure is to high or the motor runs poorly.. its matanance catches a lot of people by suprise..

My 115 hp VST tank cracked and I don't remember hitting anything. Just got a call from the shop $1100 for the part Good vid thanks

Thank you, this is very helpful!

The hose clamps are called Oetiker clamps. Great video, thanks.

Thanks man saved the day for me! Routed the tube's wrong lol

Interesting I like learning about stuff I work on small two stroke outbords I do have a 1984 115 hp Evinrude I also work on thanks for the info

Well explained , need to change a mates hi pressure pump. Cheers.

The VST system takes low pressure fuel , delivered from the low pressure diaphragm lift pump cools it with a coil supplied with pressurized flowing water from the water pump to ensure it does not form vapor bubbles, providing a reservior of cooled fuel to inlet of medium pressure electric fuel pump, (which I know has fine mesh inlet screen that can get plugged on some of the VST designs) causing a low fuel flow and low pressure issue something to look into, its second function is it contains a spring loaded fuel pressure regulator that also has a very fine mesh filter in its fuel flow path, (if this gets clogged the fuel pressure regulator can not release the extra built up pressure from the pump and you end up with fuel pressure that's way too high as well as this issue putting a lot of added stress on the medium pressure fuel pump" This fuel flow loops through the injector housing , "cooling" the injectors powerful electromagnet driven by high current pulses from the EMM that's why there is a return loop circuit back into the body of the VST "Through the pressure regulator contained within it" , The electromagnet inside the E-tec injector is fired by a timed high current pulse hammering the plunger down inside the injector to create the very high pressures needed to deliver atomized spray of fuel from the injector nozzle into the cylinder, as its timed to fire that pulse while piston has passed the exhaust port its injecting fuel into a cylinder that is under high compression already so the injector has to overcome this. . Its the medium pressure fuel pumps job to insure the injector always has a supply of cooled fuel with no vapor bubbles within its volume. supplied at the correct pressure, as the medium pressure pump operates and builds pressure in the injector loop it opens the spring loaded pressure control valve and the heated fuel from the injectors returns to the VST to be cooled by the cooling coil, then is pumped back through the loop through the injector body again to supply fuel to the injector plunger "and" once again cool the Electromangnet so the injector does not cook itself with heat buildup.. if the internal cooling coil leaks you will end up with water in the fuel going through the injectors and this destroys them in short order (its a really bad issue for motors run in salt water) if left to sit due to the corrosion and fuel breakdown within the injectors fine passages (The injectors also have fine mesh screens within them them that can get plugged with the gunk these can be changed or sent in to be cleaned ) kzfaq.info/get/bejne/qeCGjLF5zsunkoU.html and not surprisingly causes serious run ability issues

the "fuel pump" though technically correct as its the same traditional diaphragm type used on a million other OMC models, actually acts more like a "lift pump" in an Etec, drawing fuel from the tank, to the VST but the main high pressure fuel pump is the real critical one, circulating fuel to and through the injectors and back to the VST for cooling and dumping the excess into the crank case.

Hope you get it fixed soon and back on the river.

Kind of pricey but I'm glad you got it fixed. ✌👍

Solid information! Right on!

Thanks I really learned a lot with your video

This is an amazing explanation. The old VST you have there has shraeder valves to test fuel pressures, do you have any idea how to test pressures on the new VST? I don't see any external connection points. Mine looks like the second on a 90hp, but I'm the second owner so maybe they had it replaced and this is the new version? Not sure.

great vid very helpful

hello my friend. My Evinrude etech 30 hp engine is leaking oil from the tail joints. The smoke is not coming out completely from the exhaust, I think the engine is choking and not working properly. Why does this?.. What should I do?..Thank you..

I just disassembled an old Carter VST that was replaced for about $700.00 just to see the insides and to my shock there was no coil inside that should hold the cooling water. What the heck??? There had to have been one there or we would have been mixing water and fuel. I hate to think that the mechanic took it out before returning my old parts which I requested, but I can't think of anything else. Really???? Your video made me curious to look. Wow!!

Great video!! Thank you , just replaced the same thing yesterday…. I have a question, did you install the water restrictor? I mean is it there. For a reason that you have noticed ? Perhaps with this new brand of pump it requires a different pressure to reach all the parts in the water circuit cooling circuit? Curious to know why is there

Is the fuel/vapor pump usually replaced on Evinrude's 3-year maintenance schedule? I have a 2010 ETEC 40. Thanks for the video.

Interesting tape - thanks for sharing. Well done on finding the broken component - whoulda thought hitting a rock with the bottom of the boat would break something near the top of the motor I guess you must have investigated ways of repairing the damaged item ?

Do you have the old pump ? Desperet need of parts 😅 and thanks for a really usefull video! Learnt a lot!

Hey man great video can you add a link to where you bought the kit from thank you

Saw a you Tube vid by a John boat company advertising "gator bottom" epoxy coating to slick up rock bouncing,help stop getting stuck in low water conditions..just sayin..after you recover from motor repair hit, give it some thought. My buddies drift boat was night and day difference after we plasticed bottom

Wow! That’s going to cut into this years profits.

Which plastic ones you talking about? JetWolf of Russia has one you can smash over and over with a sledge hammer and won’t break. Check them out on Instagram. I wanna get one

How much you asking for old fuel pump ?? Need one