drilling out fuel bowls for a sight plug (holley)

[a70eliminator]

Do you thing it would be a mistake If I were to drill a hole and tap for 1/8" pipe plug. I can find the the exact location with any holley bowl that has the sight windows, I'm using the adjustment procedure making floats level with the bowl when inverted but would like to be sure the level is right, if I could just pull a plug to verify the fuel level it would be just grand. I'm chasing a problem with idle screws non responsive and have gone through everything 3-4 times.

 

[Don S]

Re: drilling out fuel bowls for a sight plug (holley)

If you adjusts it properly and by the book, the float level won't be your idle problem.

 

[a70eliminator]

Re: drilling out fuel bowls for a sight plug (holley)

Your right i'm just grasping at straws here, thought maybe defective float or seat.

 

[Don S]

Re: drilling out fuel bowls for a sight plug (holley)

Have you used a vacuum gauge?

 

[a70eliminator]

Re: drilling out fuel bowls for a sight plug (holley)

No I haven't yet, I guess thats next, would I get acceptabe vac readings with the guage stubbed in the pcv line out the rear of the carb baseplate? I don't see anywhere else to tap in unless there's a pipe plug somewhere on the 5.8 manifold.

 

[Don S]

Re: drilling out fuel bowls for a sight plug (holley)

You need to have it attached to a port in the manifold, not the carb.

 

[a70eliminator]

Re: drilling out fuel bowls for a sight plug (holley)

I'm hoping I've finally located my problem, I was looking over the intake manifold and decided to go aread and break loose the carb spacer, I didn't do it before cause it seemed so tightly adhered to the manifold that it couldn't possibly leak, I was wrong. It did take a small pry to pop it loose, but what I found under it was a deteriorated brittle petrified gasket that had rust under it. It sure looks awful suspicious I'm crossing my fingers. A vacuum measurement was probably the most important test that I did not do, I figured a leaking carb base would have caused the motor to not even run.

 

[Benny1963]

Re: drilling out fuel bowls for a sight plug (holley)

not worth it it probaly wont help prob but there are tons of carb parts
for holley depending on model .
benny1963

 

[Don S]

Re: drilling out fuel bowls for a sight plug (holley)

I figured a leaking carb base would have caused the motor to not even run.

Nope, depending on the amount of leakage, about anything could happen.
Replace the base gasket and give it a try.

 

[a70eliminator]

Re: drilling out fuel bowls for a sight plug (holley)

The new gasket did the trick! It's a whole new engine, I did the idle drop method and the engine seems to like the screws at about 1-1/2 turns from seat, I ran it on the water yesterday tooled around for half an hr, shutting off and restarting here and there, gave it a WOT blast across the lake too, it's a whole different boat now, maneuvering around the docks is a breeze with the new shift cable and a rock steady 500 idle rpm. Got home pulled 1 spark plug and instead of the usual carbon black, I found a nice clean looking off white. Carbon build up on valves is most likely all burnt away too. Now I can put her to sleep for the winter, thanks for all your advise.