VST Maintence

[Kirk Gibson]

Can't hit the filter

I asked about spraying carb cleaner into the F150 ...Rodbolt says you can't hit the filter on the F150. With that in mind I wonder if the cleaner would do any real good applied in that manner. Probably would give you more piece of mind to just take it apart and replace or clean the filter. ...then you know it is right.

[Nautical]

The VST is aluminum . Electrolysis with dissimilar metals with perhaps a pump, fitting etc or fuel circuit will have a corrosive effect on the vst. This corrosion will flake off as tiny pieces and clog the fuel injector screens. It is therefore very important to keep water out of the fuel hence VST . Fuel separation is usually the culprit..I have no cure to offer except to drain the VST under long lay ups.Keep the float and the needle valve wet .. I have generators that are laid up for long periods and I drain my carbs , and fill the float bowl with Mineral spirits. Its a light oil. Drain before starting. This works well for me..outboards should be the same , but I don't know. I am sure someone will find fault with it and that will be a good thing for discussion

[TownsendsFJR1300]

It is therefore very important to keep water out of the fuel hence VST . Fuel separation is usually the culprit..I have no cure to offer except to drain the VST under long lay ups.Keep the float and the needle valve wet .

I don't have ANY issues with water getting in or separating in the VST. Between using Non-ethonol fuel and using a product called k100;

Fuel Treatment, Fuel and Gas Additive | K-100 HOME

Demonstration | Fuel Additive | K-100

All my water issues are gone.

The water, over time(and I did have water in the VST prior to K100 and non-ethonol fuel) burned off. I can drain the VST right now and the fuel will come out clear, no water droplets, no cloudyness, smells new, etc. Using Ringfree also helps in keeping the fuel system clean. EXCELLENT PRODUCT..

I do carb cleaning on small engines (mostly varnish in the main and idle jets), and am very familiar with the inside of a carb, wether it be Rochchester, B&S, Tecumseh, Walbro, etc...

Unless the carb is super bad, I use brake cleaner as I've seen carb cleaner distort / enlarge 0-ring seals, etc. Manually looking into the critical jets is what matters, not just sticking it in a sonic bath..

That's my main concern shooting carb cleaner into the VST.



As a side note, for any small engine that's going to stored for more than a month, the bowl gets either drained or removed and drained. A couple of teaspons of Seafoam get put into the top and cranked (not started) for distribution. If a 4 stroke, its stored at TDC with all the valves closed(to keep moisture out)

[boscoe99]

If a 4 stroke, its stored at TDC with all the valves closed(to keep moisture out)

How do you get all valves to all cylinders closed at the same time?

[TownsendsFJR1300]

How do you get all valves to all cylinders closed at the same time?

Single cylinder mowers, weed eaters(2 and 4 strokes), chain saws, generators, etc, most under 10HP...

For two strokes, same procedure with the Seafoam BUT leave it at TDC(obviously no valves to watch for)..


Some of the newer engines have low speed and high speed adjustment needles set so lean that after a couple of hours of operation, the machine won't idle(or idles super high), or bogs badly when accelerating.

Adjusting those screws for a richer mixture fixes the issue. I fine tune with a clamp on tach (over the spark plug wire) to get the highest RPM's, NO bog/hesitation, trying to keep it towards the rich side... With the tach, I can easily pick up another 1,000 RPM.

Its also NOT unusual at all for machines (especially the smaller ones) to come in with the carb varnished up 95% of the time and fuel lines completly deteriorated from the ethonol.