# carburetor torque question - 74 GTO



## Red74Goat (Jul 31, 2015)

I'm working through vacuum leak troubleshooting, want to make sure carburetor is torqued correctly. Doug Roe says 10-14 ft-lb or torgque on carb bolts, while Rocky Rotella says 5 ft-lb. This is the original q-jet and original cast iron intake manifold. New carb gasket in place.

Any suggestions?

Thanks.


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## ALKYGTO (Mar 29, 2010)

First suggestion, remove the carb and ensure that the baseplate isn't warped by holding something flat, like a scale, against the base. Over tightening can warp the base and then it will never seal.

Next, what gaskets are you using?

I've always used 10 ft. lbs. as a reference, its not very much but you just want it to seal and not loosen up. Over torqueing can crack an ear on the base plate or warp it.


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## Red74Goat (Jul 31, 2015)

ALKYGTO said:


> First suggestion, remove the carb and ensure that the baseplate isn't warped by holding something flat, like a scale, against the base. Over tightening can warp the base and then it will never seal.
> 
> Next, what gaskets are you using?
> 
> I've always used 10 ft. lbs. as a reference, its not very much but you just want it to seal and not loosen up. Over torqueing can crack an ear on the base plate or warp it.


Thanks Alky, I don't remember the gasket brand, will need to check when I get home. 

Any thoughts about the tightening sequence on the intake manifold? I replaced the original with Fle-Pro and torqued it down, but I may have misread my torque wrench in the evening when I was re-installing the manifold and under-tightened them just a bit. I had a diagram that showed a recommended tightening sequence, but can't seem to find it again. 

Thanks.


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## ALKYGTO (Mar 29, 2010)

On the intake my rule of thumb is usually center/out, that is starting in the center and working my way out, side to side. Also don't torque to max on the first go round, work your way around the manifold a couple of times, progressively increasing torque to max.

Here ya' go- https://www.google.com/search?q=tig...oTCK_OlNaAs8cCFUVrHgodmxUNzg&biw=1600&bih=775

Funny, the first two images show Pontiac V8's and one starts at the outside working in, the other starts in the inside and works out. :banghead:

gotta love the interweb.....:thumbsup:


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## Red74Goat (Jul 31, 2015)

ALKYGTO said:


> On the intake my rule of thumb is usually center/out, that is starting in the center and working my way out, side to side. Also don't torque to max on the first go round, work your way around the manifold a couple of times, progressively increasing torque to max.
> 
> Here ya' go- https://www.google.com/search?q=tig...oTCK_OlNaAs8cCFUVrHgodmxUNzg&biw=1600&bih=775
> 
> ...


Got it torqued properly, looks like the vacuum leak is fixed. 

Thanks for the suggestions. Now on to the next challenge with the transmission downshift.


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