Yeah it is. this is what happens when you forget the hole is there and cover it....
But still the insulator does NOT have such hole .... so what is the hole for?
hmmm
Carburetor Insulator Gasket
- Thread starter tundra06
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But still the insulator does NOT have such hole .... so what is the hole for?
hmmm
I have 2 early 70`s carbs on my workbench right now. Insulators have no hole and they both have the passage from the center hole with the hollow screw into the primary bore, so thats where the manifold vac is coming from. Maybe the later carbs are different.
This is a 78 from marks off road
hmmmm this is. Good mystery
what the hole really for and should one use a gasket that perhaps better seals the hole?
hmmmm this is. Good mystery
what the hole really for and should one use a gasket that perhaps better seals the hole?
bump...
Can anyone help with this mystery...
Again, some carbs have a hole in the bottom that has a bolt with a hole in it for some reason...besides to keep the two parts together
the question is what does the bolt with a hole do?
and
isn’t this just plugged up by the use of a gasket at the base of the carb? Thus defeating the purpose?
Can anyone Clarify a bit further ?
Can anyone help with this mystery...
Again, some carbs have a hole in the bottom that has a bolt with a hole in it for some reason...besides to keep the two parts together
the question is what does the bolt with a hole do?
and
isn’t this just plugged up by the use of a gasket at the base of the carb? Thus defeating the purpose?
Can anyone Clarify a bit further ?
r
I took off my carb because it was leaking vacume and I had a fluctuating vac and couldn't get a good reading on the vac gauge. Fluctuating vacume and couldn't get a 650rpm idle. The hole in the manifold was welded shut even though the carb still has one. I did have a good idle a year or so ago. I also removed the old orig gasket that was messed up. (minor scraps) Why are you recommending no gasket and should the hole be redrilled on the maniford to match the one on the carb? Thanks for any help you. can hopefully give me, thanks....beckley
You should post a picture of this. The whole big hole was welded shut? (Can't be.) There's only one hole in the manifold and it doesn't really match the two holes of the two barrels of the carb.
The insulator includes the gasket from the factory, so you shouldn't use an additional gasket if it's in good shape.
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There is a hole drilled horizontally in the primary throttle bore that provides vacuum to the chamber with the hollow screw. The hollow screw provides vacuum to the power piston to keep it retracted during normal driving.
When you accelerate moderately and vacuum drops below ~7" or so, there is insufficient vaccum to keep the spring-loaded power piston retracted and it descends, opening the power valve directly below it.
You DO NOT and SHOULD NOT drill the insulator.
I would hazard a guess that @FJ40Jim probably explained this on the forum 15 years ago, but @thebigredrocker is the only one with the search skills to find it.
When you accelerate moderately and vacuum drops below ~7" or so, there is insufficient vaccum to keep the spring-loaded power piston retracted and it descends, opening the power valve directly below it.
You DO NOT and SHOULD NOT drill the insulator.
I would hazard a guess that @FJ40Jim probably explained this on the forum 15 years ago, but @thebigredrocker is the only one with the search skills to find it.
the insulator has two holes and is what I am referring to. It also has the third hole which is sealed and would have lined up with the hole in the carb. Its about s/8 inch in diameter. It would supply vacuum if it was open. i will send pictures when I figure how how to do this.
Post up what year too.
I guess you answered that. no hole drilling as I thought. Just can't figure why the hole (about 5/8" and vertical) is in the carb.
Hey there thats sweet looking!! I see your carb insulator gasket (just under the air filter and on top of the carb) is white those always seem to die early who made yours and where did you get it? Will it last longer then normal ones?
don't think this was intended for Beckley?
its a 1978.... thanks
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The extra hole in the gasket is because the gasket is also used in a DIFFERENT APPLICATION where a hole is needed. It is not needed on the Landcruiser carburetor.
Hey there thats sweet looking!! I see your carb insulator gasket (just under the air filter and on top of the carb) is white those always seem to die early who made yours and where did you get it? Will it last longer then normal ones?
thats it exactly but with no seal for the carb. It has leakage of vac, so I think the only answer is a gasket even though you say we shouldn't need one. I did spray starter fluid around the base before removal and the rpm's increased. thanks for your help over my rebuild and also today. thanks to all the forum members for your replies. It;s a big help
It's not supposed to need one, but if it does, it does. Make sure all the original gasket material is sanded flat.
