Rebuilding carburetors

[Johndhii]

When rebuilding my carbs, do I need to replace the plastic float bowls with aluminum ones?

 

[dew2]

Re: Rebuilding carburetors

Thats up to you,I have read here at Iboats of the plastic warping because of over tightening.I never had any plastic bowls so I lack experience.But I read tighten them just so they are fixed and not leaking.I myself would use a bit of lock tight and not over tighten.

 

[Johndhii]

Re: Rebuilding carburetors

I appreciate the reply, Dew. Both mechanics I spoke with have said that they always replace them, I am trying to figure out if it is preventative or necessary

 

[smsscuba]

Re: Rebuilding carburetors

My bowls are also plastic and are leaking ever so slightly.I would recommend replacing the originals with aluminium.One is tempted to overtighten the retaining screws to make a tight seal, but this just deforms them, enough to create a leak.

Some plastic bowls, like mine have a raised ring running the entire circumference of the bowl, so I can`t even slightly flatten then on a pane of glass.

 

[scanman]

Re: Rebuilding carburetors

The advantage of plastic bowls is that they don't corrode or rust over the winter, sending trash throughout the carb's jets when you crank it the next spring. An extremely small layer (not a "bead") of some type of sealer can help if they've been leaking. I usually smear a thin layer of OMC gasket sealer on with my finger. I use that stuff 'cause it never really "sets" like silicone, so if a lil bit gets in the bowl when you tighten it down, it won't cause a problem. Just make it a thin layer. This way you can get them to seal, without overtightening & warping them. Not sure, but this may be cheaper than buying new bowls. The alluminium bowls are great too, as long as you run the engine dry every fall before you put it to sleep for winter.

 

[jonesg]

Re: Rebuilding carburetors

Don't use loctite on plastic. It will strip the threads when removing.

A local iBoater showed me a trick for checking the seal, turn carb upside down and put a small tube on the feed nipple, blow through the tube as you tighten the screws, when you sense the bowl seal just snug the screws a bit more and its done.
Steel screws in nylon don't work loose even under extreme vibration, its not a problem that requires cranking down on the bowl screws.

 

[scanman]

Re: Rebuilding carburetors

A local iBoater showed me a trick for checking the seal, turn carb upside down and put a small tube on the feed nipple, blow through the tube as you tighten the screws, when you sense the bowl seal just snug the screws a bit more and its done.

That's a neat trick! If you turn it upsidedown, you can check the needle & seat operation.