V s t service

[KIRCHNER]

The vst in my 88 220 efi i dont think has ever been serviced. i read about internal filters and screens that need to be cleaned. the bottom hose is capped off. not sure if its functioning at all. what do i need to know about this gizmo, dont want to open a can of worms. worms, thank you. art k.

[Jim Speros]

What is your serial number. There a few variations. The early like yours use a formed O ring to seal top. They usually swell and need to be replaced once opened. I would check to see if what you may need is available before you actually open it up.

[Jim Speros]

Earliest has a U shaped hose on bottom to exposed fuel pump. There is a filter in that U hose.

[KIRCHNER]

thank you 220for responding jim, yes i have a u hose & fxposed pump. eng#0b211002 87 2.4 i have 36psi at the schrader. that lower fitting has a plugged short hose, going nowhere? also on the port side engine block i see 3 bleed nipples, cyl #2,4,6, 2 an4 have caps on nipples, 6 has a bleed line on. why no lines on 2&4? bought motor from original owner, never apart but i dont know who worked on it. i made it pre-mix, thats it.

[Jim Speros]

I looked to Mercruiserparts.com for your engine by serial number. Its temporarily down for revisions. I like to see the mercury parts diagrams for reference.
Can you share a pic of fitting with plug? There are a number of hoses connecting to Cannister. Oil in, overflow, bleed return. Sometimes there will be a fitting capped.

[Jim Speros]

I agree with your instinct not to want to open a can of worms. To that point I like to confirm there actually is an issue before opening a VST on an older engine.

[OnPad]

Just from my foggy recollection, the lower nipple went to your oil injection. You probably removed it when you deleted the pump. Blocked is fine, or you can purchase a plug, if you can figure the thread size. I've heard you don't even need to plug it, as there is a check valve in it, but mine dribbled a bit.
Bleed lines sound right for efi.
There is also a screen up by the regulator, I believe.

[tlwjkw]

pad is close.. tha one on tha bottom of tha tank is a "check" valve, it needs nothing even with tha oiler working.. some put a cap on jus 'cause it appears ta have a bib stickin' out... tha bleed lines all sound right.. there are two bleed systems on tha '87 efi.. yours sounds like tha "old" design..... ya might find a dia on crowley's web site?

[KIRCHNER]

No filter in the u hose, upper filter clean.