JaayTeee

BAM marines site shows
exploded part breakdowns
here's the linkmercruiserparts.com
Look up your engine, click on VST,
it will show you the breakdown.

radams3

ST31....

Is your problem fixed ? was the problem your diaphragm in the VST ?

I too have developed a similar problem today....and I will be doing the test described above.

DanB

Had the same problem. Early style VST diaphragm went bad sending fuel to #8 cyl. I wound up getting the new style that dumps fuel back to the mech fuel pump return line. Be careful..if you run it that way you could wash down #8 and need a ring job. Or worse.

radams3

DanB:
Can you elaborate a bit more about the "new style" return line you installed (e.g. how to install, cost, etc.).

I am going to test my vent line today to see if it is in fact leaking (by instaling a clear fuel line in series, if it is, then I'll obviously repair it ASAP. I am interested if there is a "better" method for the overall repair such as you described in your reply.

I sincerely appreciate your time and respone to my inquiry....Again, Thanks !

DanB

Part #'s
808508A01 VST top cover Kit......278.00
808503 elec fuel pump connect kit...71.00
Reused the pump and VST body
Remove entire unit..Pull out the old parts and install the new, re install and put a T fitting in the mech fuel pump return line.

radams3

Dan --- thank you for the information. I check my vent line (by rigging a clear tube in series with the existing vent line) and sure enough, fuel was spilling thru the line. This "leak" was causing me to run rich/spilling raw fuel out my right hand side exhaust. Fifteen minutes of work and the fuel pump was removed, and right nor it sit on my workbench ready for the new parts.

Thank you for the information and quick follow-up.

I'll be back on the water a soon as the new parts arrive !

radams3

Problem fixed.....the VST diaphram was the problem.....overall, this was an easy fix. $50 for the diaphram and $18 for a float seal, and everything went perfect.