New Manifolds

F

flathead 1150

Member
Hi, I replaced a complete exhaust including a new intake and exhaust manifolds, on a 30 pickup, I used a one piece manifold gasket and torqued the bolts 35lbs. The truck ran fine prior to doing now the engine to not even try to fire. I am planning on replacing the gasket with the two piece ones and torque to 65lbs. Hopefully the engine run after doing this, any thoughts out there about this thanks
 
flathead 1150 said:
Hi, I replaced a complete exhaust including a new intake and exhaust manifolds, on a 30 pickup, I used a one piece manifold gasket and torqued the bolts 35lbs. The truck ran fine prior to doing now the engine to not even try to fire. I am planning on replacing the gasket with the two piece ones and torque to 65lbs. Hopefully the engine run after doing this, any thoughts out there about this thanks
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Check for a vacuum leak with wd 40 spray around the intake and listen to the idle if it changes that's your problem. Your sucking air in
 
Were the face planes of the manifolds the same? 35# torque is best unless you want to buy new parts again.
 
flathead 1150 said:
Hi, I replaced a complete exhaust including a new intake and exhaust manifolds, on a 30 pickup, I used a one piece manifold gasket and torqued the bolts 35lbs. The truck ran fine prior to doing now the engine to not even try to fire. I am planning on replacing the gasket with the two piece ones and torque to 65lbs. Hopefully the engine run after doing this, any thoughts out there about this thanks
Click to expand...

John has given you good input, IMO.
I wouldn't do 65 lbs , till you have tried a gradual increase / re-torqueing after hot/cold cycles. Cast ears and alum ears (intakes)SNAP easily with tooo much torque. Best to use caution after installing new gaskets.

BEFORE doing anything else....ensure that your mating surfaces are flat/true and all clean. Intake/exhaust surfaces should match up,eh :)
 
With both being new manifolds they should not need planeing,,
As the others mentioned ck the basics spark / fuel
 
If your engine"won't even try to fire", I don't see how the new gasket can be causing this? Even if you had a big gap, I'd think you would get something. Do you have gas in the carb? Do you have spark at least from the coil to ground? Did you remove anything else ,beside the carb, during this gasket change?
 
JOHN CT said:
Check for a vacuum leak with wd 40 spray around the intake and listen to the idle if it changes that's your problem. Your sucking air in
Click to expand...
Oops I was thinking he said it wouldn't start now. So by spraying wd 40 wouldn't help.check Spark and fuel.
 
I swapped mine out once and managed get the gland ring to pop out on #4. It would just crank and crank. I pulled it off again and repositioned the ring, tightened everything down and she fired right up.

Mike
 
flathead 1150 said:
Hi, I replaced a complete exhaust including a new intake and exhaust manifolds, on a 30 pickup, I used a one piece manifold gasket and torqued the bolts 35lbs. The truck ran fine prior to doing now the engine to not even try to fire. I am planning on replacing the gasket with the two piece ones and torque to 65lbs. Hopefully the engine run after doing this, any thoughts out there about this thanks
Click to expand...

If you use 65lbs you need to order a new manifold. That is way to much. I would never torque the manifold. I would go by feel, just enough to seal, and then check it later.
 
Did you turn the rotor and upset the timing?

Also make sure your spark is reaching the plugs, we have seen bad rotors and dist body's.
 
many Model A mechanics references, and others, have errors.
It helps to have previous mechanical experience to ferret these out.

Andrews wants you to torque pan bolts to 20 ft-lb. Go ahead, and you'll shear them off.

The thing to remember about manifolds, especially exhaust, is that they have to live thru very wide temp swings.....from ambient to hundreds of degrees. Thus, they have to be able to expand and contract. In fact, they WILL expand and contract. If you have them torqued to 65, then they cannot move around under the special washers, and they WILL crack/break instead.

This is true for any vehicle. So, 25-30 max

A friend was setting preload on a pinion bearing (not model A) and the book said 20 ft-lb. I said, ummm, no. He did it anyway. Pinion bearings exploded at 400 miles. Book shoulda said 20 in-lbs
 
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