F225 TXRC bogging down - fuel rail pressure question

[Crazy Train]

not to be capt obvious here.
but does anyone understand the pump motor has brushs?
does anyone understand that gas flows over the armature,over the commutater/brush set and out the outlet?
does anyone understand where the brush dust goes?
it is called maint.
do it.

Rodbolt, thanks that's good info that was not obvious to me. This means the dust, if it doesn't make it to the cylinder to get burned, is filtered out by the two toughest filers to get to - the injector filters or it recirc's to the HP pump filter.

[Crazy Train]

Interesting. Not sure what vents when it is being filled. There is a break "valve" to vent to intake. 10 psi according to Fairdeal.

At any rate, not that big a headache to remove VST to clean. Now those little screws and funky gasket can be aggravating.

Yeah those little screws are sporty!

[boscoe99]

not to be capt obvious here.
but does anyone understand the pump motor has brushs?
does anyone understand that gas flows over the armature,over the commutater/brush set and out the outlet?
does anyone understand where the brush dust goes?
it is called maint.
do it.

Which raises the question, why not use a brushless DC motor?

Better reliability. Less maintenance costs. Less profit for dealer mokanics.

Oh, while they are at it, make the lift pump motor variable speed so that it does not have to over work and heat up the gasoline any more than necessary. Take out the crap return lines and expensive pressure relief valve that fails and makes everyone go crazy.

[rodbolt17]

not to be capt obvious here.
but does anyone understand the pump motor has brushs?
does anyone understand that gas flows over the armature,over the commutater/brush set and out the outlet?
does anyone understand where the brush dust goes?
it is called maint.
do it.

[zenoahphobic]

Wouldn't it be nice if everything had sight glasses and tubes to fill and drain things easily.
Most things end up with unwanted messy spillage.
I hate oil filters, especially on Diesel engines. Most invariably spill that black staining oil at the spin off. Why can't there be a special catching ledge under them? And space to turn them upright and to extract them vertically!.
Bit off topic but one can do a lot of modifications and retrofitting after buying a new vehicle/boat etc. to make servicing easier.

[boscoe99]

In most Yams the VST is vented to the atmosphere via the charcoal cannister in the vapor recovery system.

I seem to recall some early models not using the vapor recovery system simply vented the VST directly to the atmosphere.

[pstephens46]

I am under the impression that the VST is not open to outside air until a relief valve opens. fuel in VST does not evaperate away like a carb bowl

Interesting. Not sure what vents when it is being filled. There is a break "valve" to vent to intake. 10 psi according to Fairdeal.

At any rate, not that big a headache to remove VST to clean. Now those little screws and funky gasket can be aggravating.

[99yam40]

The VST isn't under pressure(not much to speak of till the float shuts off the needle valve)... It's got a needle and float and a vent:

\ Maybe a misunderstanding, or I missed something..

I am under the impression that the VST is not open to outside air until a relief valve opens. fuel in VST does not evaperate away like a carb bowl

[TownsendsFJR1300]

For VST access, I was also thinking of 1 inch diameter tube, threaded on the outside, that is capped off with a female cap similar to a wide-mouth oil container, but that visi flow window would be perfect - clear to see in AND access to suction off the HP pump screen and VST bottom.

Once the VST is clean, you shouldn't have to go in there again (any time soon) with proper filter changes, etc...

I've never changed /checked the VST filter on my engine (original owner) but I keep after exterior filters, drain the VST on occasion and use fuel additives (Non-ethanol fuel too).

BTW, it has been mentioned in previous posts you can spray carb cleaner up the drain in the VST. Wether the spray would actually hit the filter, dunno for your engine. Probably couldn't hurt(and easy too).

.

[TownsendsFJR1300]

those float chambers are not under pressure like the VST is.

The VST isn't under pressure(not much to speak of till the float shuts off the needle valve)... It's got a needle and float and a vent:

2004 F225TXRC Yamaha Outboard FUEL INJECTION PUMP 1 Diagram and Parts



Maybe a misunderstanding, or I missed something..

[99yam40]

those float chambers are not under pressure like the VST is.

[Crazy Train]

I don't remember the above carb but Holly and others DO have a see thru "plug" (approx 1" across) for adjusting the float level correctly(with the carb installed), see below.

For the OP, did you drain the VST and see if any crap came out?

Should be one screw on the bottom and a hose connected. Obviously catch what comes out in a small clean container.

I'll drain mine occasionally AND prime the bulb to push fuel thru it for inspection/flush..


.

I did drain the VST into a separate cup: no visible crap. I have a screw on the side but not a place to connect a hose. I use a 6 inch long 'chute' that drains into the cup. I did not pump the bulb to push the gas through since I was by myself and had to hold the cup, but will do that next time with help.

For VST access, I was also thinking of 1 inch diameter tube, threaded on the outside, that is capped off with a female cap similar to a wide-mouth oil container, but that visi flow window would be perfect - clear to see in AND access to suction off the HP pump screen and VST bottom.

Thanks!

[TownsendsFJR1300]

Anybody else remember the Holley "Visi-flow" used on Fords and IHCs?

I don't remember the above carb but Holly and others DO have a see thru "plug" (approx 1" across) for adjusting the float level correctly(with the carb installed), see below.

For the OP, did you drain the VST and see if any crap came out?

Should be one screw on the bottom and a hose connected. Obviously catch what comes out in a small clean container.

I'll drain mine occasionally AND prime the bulb to push fuel thru it for inspection/flush..


.

[boscoe99]

Anybody else remember the Holley "Visi-flow" used on Fords and IHCs?

I also remember glass bowl gascolators.

[boscoe99]

The HP pump filter does not really need to be within the VST.

Gasoline initially entering the VST has been filtered by the primary fuel filter. That gasoline having normally already having been filtered by a boat mounted water separating fuel filter.

The HP pump filter I suppose it to try and capture any contaminates that have gotten into the fuel system either from the pump itself or down stream from the pump. An external filter could be mounted adjacent to the VST to filter any bypassed gasoline that needs to re-enter the VST.

Were I the engineer that is the way I would do it. But if I owned the company there would no VST installed at all.