Replace high-pressure fuel pump in VST and now fuel pouring out at the ….

[jkscarab]

Ipugh. Thanks so much for the added detail. Its cumbersome writing what is 2nd nature to you but I appreciate the added info. I am on hold till I get the new part/ VST needle float kit.

[jkscarab]

JOE54. Thanks again for your continued help on this thing. I appreciate the added detail. I ordered a new needle float kit/arrives Wed.
The only variable is cleaning the "bore of the seat". I assume carb cleaner and a little tooth brush kinda thing if I see anything suspicious (oxidation)? Or is there a "pro" way to clean that bore/seat aside from removing it. Ugh...

Now that I understand what the failure is and how fairly straight forward the fix is. I am going to replace the needle on my "good/working" motor. The idea that the other motor will have this problem on the water with fuel gushing everywhere is a good way to ruin a weekend. Sooooo again, any clue on how to clean that bore/seat is most welcome.
Thanks thanks

[JOE54]

ive used crome polish and a wooded Q tip in a slow speed drill mtr on every pressed in seat as far back as i can remember late 1970s , just a tiny bit is all you need on Qtip

[lpugh]

If a metal needle, not vitonuse pin punch and 1 oz hammer to make perfect needle seat seal, just a couple of light taps on the needle to form it, coated needles will take care of themselfs,

[jkscarab]

JOE54 you wrote, "ive used crome polish and a wooded Q tip in a slow speed drill mtr on every pressed in seat as far back as i can remember late 1970s , just a tiny bit is all you need on Qtip" . I feel like you are revealing the secrets of your "wizardry"!! Haha, now I gotta find some wooden Qtips :) Thanks for your continued detailed input as I fumble around learning.

[jkscarab]

Ipugh, your comment mentioned hammers and pin punch. At that point I submit to a professional for fear of doing more damage than good. Thanks for your continued input.

[JOE54]

plastic stem will work also

[EuropeanAM]

DO NOT hit or punch the needle. Virtually all of the Mercury VST needles are viton-tipped.

[jkscarab]

EuropeanAM you wrote: "DO NOT hit or punch the needle. Virtually all ...." Understood!! Thanks for the follow up.

And JOE54 I found some wood Q tips on amazon. For some reason I am now "into" understanding/fixing my situation. Thanks for your continued follow up assistance.

I ordered the new needles from EuropeanAM who said I should receive Thursday. bamboo.JPG

[jkscarab]

Continuation of -not- being able to get VST needle to shut off properly and therefore showing fuel into throttle valve.
Since last message several things accomplished.

1. Polish tang on float to smoothen surface (drill with Qtip/aluminum cleaner).
2. Polished inside of needle valve bore (same as above=Qtip in a drill with aluminum cleaner) and sprayed out with carb cleaner.
3. New needle valve from European AM

Assembled VST again and pumped up primer bulb which seemed to harden significantly but then I could continue pumping primer which would present fuel again as originally shown in previous messages at throttle valve. Squeezing bulb presented far less fuel than earlier but still plenty of fuel to drip into engine cowling. I have a second engine for comparison which when I pump up primer bulb the bulb hardens rock hard and zero fuel at throttle valve (totally dry).

Next- I separated the top/bottom housings of the VST to manually lift the float with a very soft rubber band to holding up the float. I again pumped up primer bulb to see if the needle would shut off fully which it did. Did not leak a drop of fuel or any air for that matter. I cannot just turn the VST over to let the float hang down from gravity as I did not want to disconnect the top fuel hoses (again).
Observation see pic at bottom: Either with the rubber band or manually pushing float up with qtip I noticed the float travels past horizontal which seems abnormal and discussed often on forums as not being “correct”. All documentation suggests float should shut off horizontal with VST housing top/bottom line. As the primer bulb does harden significantly as is I feel like I am just a tiny distance from the needle shutting off fully.
float with text 2.JPG
NEXT STEPS? I am thinking my next steps are to add a little 0.020” piece of brass to the top of the float tang where the needle sits to raise the needle a tiny bit as a test to see if needle shuts off. IF the needle shut off properly I could just “adjust” the float tang to represent what the 0.020” is giving me. I like the idea of adding a little extra 0.020” flat brass piece as I can easily remove it/nothing permanent.
Any thoughts / Ideas are most welcome!!! Again, I feel like I am an RCH close to this thing working perfectly as the primer bulb is getting quite hard …thanks in advance.

[jkscarab]

>>>>Any thoughts most appreciated trying to get it done before Memorial day .

Continuation of -not- being able to get VST needle to shut off properly and therefore showing fuel into throttle valve.
Since last message several things accomplished.

1. Polish tang on float to smoothen surface (drill with Qtip/aluminum cleaner).
2. Polished inside of needle valve bore (same as above=Qtip in a drill with aluminum cleaner) and sprayed out with carb cleaner.
3. New needle valve

Assembled VST again and pumped up primer bulb which seemed to harden significantly but then I could continue pumping primer which would present fuel again as originally shown in previous messages at throttle valve. Squeezing bulb presented far less fuel than earlier but still plenty of fuel to drip into engine cowling. I have a second engine for comparison which when I pump up primer bulb the bulb hardens rock hard and zero fuel at throttle valve (totally dry).

Next- I separated the top/bottom housings of the VST to manually lift the float with a very soft rubber band to holding up the float. I again pumped up primer bulb to see if the needle would shut off fully which it did. Did not leak a drop of fuel or any air for that matter. I cannot just turn the VST over to let the float hang down from gravity as I did not want to disconnect the top fuel hoses (again).
Observation see pic at bottom: Either with the rubber band or manually pushing float up with qtip I noticed the float travels past horizontal which seems abnormal and discussed often on forums as not being “correct”. All documentation suggests float should shut off horizontal with VST housing top/bottom line. As the primer bulb does harden significantly as is I feel like I am just a tiny distance from the needle shutting off fully.

NEXT STEPS? I am thinking my next steps are to add a little 0.020” piece of brass to the top of the float tang where the needle sits to raise the needle a tiny bit as a test to see if needle shuts off. IF the needle shut off properly I could just “adjust” the float tang to represent what the 0.020” is giving me. I like the idea of adding a little extra 0.020” flat brass piece as I can easily remove it/nothing permanent.
Any thoughts / Ideas are most welcome!!! Again, I feel like I am an RCH close to this thing working perfectly as the primer bulb is getting quite hard …thanks in advance.

[EuropeanAM]

Remove the top of the VST so you can work on it without stuff in the way.

Turn it UPSIDE DOWN.

Float should be parallel to the mounting surface of the VST top.

If necessary, carefully manipulate the metal TANG of the float to achieve correct level. Make sure total float drop does not exceed the depth of the VST (don't want float vibrating on bottom of VST, or hanging up on it).

[jkscarab]

Thanks EuropeanAM for detailed instructions,

I am 100% confident Top of float is NOT parallel to VST top housing. I had the VST top housing fuel hoses all removed previously and noticed this (not parallel) but didnt take a photo at the time I thought it was the mark on the tang of the float (which I subsequently polished perfectly smooth).

One good finding is I purchased a new in bag OEM float on <Please Read Announcements> so I have a back up.

Question: Per you instructions, "carefully manipulate the metal TANG of the float to achieve correct level."

Procedure>> I assume if I need to "manipulate"the tang I simply press down on the underside of the tang to raise the needle a little bit. I assume I just press down with a flat blade screwdriver a few 0.010" at at time until the float is parallel to the top of VST?

press tang.JPG
Thanks! I see light at the end of the tunnel.

I wonder how this needle/float not parallel problem came about? Obviously, everything worked fine for 20 years...is it possible the needle valve seat got pressed in somehow not allowing the needle to seat properly?

[EuropeanAM]

You're correct in your method. Just be extremely careful to place NO pressure on the needle against the seat. Theoretically better to remove float to make adjustment, but admittedly... I do it with them installed.

Let's leave Flea-Bay out of the forums. We don't support them, or anything purchased from them (see Forum Announcements) here- so we'll overlook that one this once.

[jkscarab]

Yes, yes...my bad=Flea. Recall motor is a 1998 and that part is discontinued by mercury, else I would surely have sourced from you as I did the needle etc. I got your parts within 3 days to Florida btw. Fast ship/very convenient...

Anyway thanks for your continued help in getting my problem repaired.

[EuropeanAM]

[jkscarab]

Looking for a visual guestimate confirmation (see pic below). The float tang was super touchy and Im wanting to use the boat this weekend. My simple high school trigonometry tells me I needed to bend the tang up about 0.020" (equal to the brass tang thickness) to achieve a parallel float at high position to the VST housing.
It has been mentioned that you guys have done this very very often and so is this amount of bend in the ball park. Again I know I am targeting parallel float to vst housing but I gotta start somewhere and adjust from there.
Any input most appreciated.

tang_2_views.JPG

[JOE54]

bending float tang in pic will adjust float level

[jkscarab]

JOE54: "bending float tang in pic will adjust float level" Thank you!!

[JOE54]

yes sir