Exhaust manifold heater flap
 

I’m not sure if the exhaust manifold heater flap is in the closed or open position. I can’t move it when the motor is cold or hot. It stays in the same position when the motor is hot. (like ran for 30 miles on the freeway) The plan if to trash it when I put a new exhaust in but for the mean time it stays. 1969 K10 suburban barn find. Sat for a few years. Now runs like a champ.

Re: Exhaust manifold heater flap
 

The only way to really Know for sure,
Is to Soak the 2 nuts in the circles with your favorite rust busting solution.
Then take those 2 nuts off (And hope you don't break the studs)
(Stop if you think you are going to break the studs.)

Even if it looks like it would be in the open position ,
PO may have beat on the weight and spun it on the shaft.

Then you will know for sure.
If it is stuck open just leave it.

I have always used brass nuts on exhaust manifold studs and Anti-seize.
Better results for removal later. JMO hope this helps.

Brass nuts: https://www.ebay.com/i/382885444081?...cc4c756fdb1338

Anti seize:https://www.ebay.com/i/264646878276?...3c86fb2fc062f5
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Re: Exhaust manifold heater flap
 

Great advice. My 2 cents is use a 6 point socket or box end wrench on those nuts. They will round rather easily.

Re: Exhaust manifold heater flap
 

Use an impact wrench. The momentary torque is much better for not breaking studs.

Re: Exhaust manifold heater flap
 

Leave it alone.
Check the temperature on the pipe.
That’ll tell you if it’s open or not.

Re: Exhaust manifold heater flap
 

You could buy a
https://www.amazon.com/Etekcity-Lase...-8&tag=mh0b-20
To check the difference would be an option also.






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