# vapor separator tank 2008 Suzuki 115



## Boat-Dude (Sep 24, 2011)

I ended up replacing my (vapor separator tank) due to multiple issues. See below.

You can remove the VST with out removing the intake manifold. You can take it out thru the top.

1. Remove black plastic flywheel (1 screw) cover and the black plastic intake cover (2x 10mm bolts from the side) right above the VST.
2. Remove the top oil pressure sender, to give you room.
3. Facing the front of the motor, remove the left side lower engine cover.
4. Drain the VST from the bottom screw that has the drain tube below it.
5. Remove lower fuel line from VST to lower fuel rail.
6. Remove lower 10mm bolt for the VST, not that you can get to it.
7. Remove the high pressure fuel filter & hose (2 x 10mm bolts).
8. Remove all other fuel hoses and small vent tub from the top of the VST.
9. Unplug electrical connector from the top of the VST to the fuel pump.
10. Remove the last 2 10mm bolts from the VST (the top bolt with a 10mm wrench and the lower with a 10mm ratchet wrench.
11. Remove VST from top.

My high pressure pump was not able to keep 38psi on the fuel rail, you will see in the pictures that the high pressure pump bushing that seals the neck of the pump to the VST was swollen from ethanol use and was cracked. This was causing the fuel to leak past the fuel pump back into the VST hence losing fuel pressure, causing drop in speed and sluggish running. This would allow the fuel pressure to bleed off making it harder to restart the motor after sitting for some time. 

In the other pic you will see the neck of the fuel pump has a check valve and retainer, there was a small piece of plastic that broke off (brittle) that would keep the black rubber check valve and white plastic retainer in the pump. Now with that broke the check valve and retainer would shoot up into the high pressure fuel filter and would not be able to hold 38psi in the fuel rail when the motor is shuts off, causing the pressure to bleed off making it harder to restart the motor after sitting for some time. 

In the bottom of the float side of the VST is the pressure regulator which didn't look great being on the bottom, I had no way of testing it and didn't want to take a chance of it not working and having to take out the VST for the second time. So by the time you replace the pump and the pressure regulator, you might as well by the entire VST unit with all new stuff including needle and seat. 

On a side note after talking with the Suzuki mechanic he informed me if you have ethanol damage to the inside of the VST coating (surface damage due to water..corrosion) it allows tiny tiny particles of aluminum to bypass the fuel pump screen into the pump causing the pump to fail over time. This added to my decisions to by a complete new VST unit.

I hope this helps anyone with this issue.


Thx to Sea-r-cy for instruction for taking it out the top.


----------



## Boat-Dude (Sep 24, 2011)

Took it out and ran it over 55 miles, good grief what a difference the new VST made. Only burned 10 gallons, so smooth and seems quieter, fired right up after sitting on a spot for an hour.


----------



## X-Shark (Oct 3, 2007)

:thumbup:


----------

