Boilerz25

I noticed that the Heat Control Valve on my exhaust manifold was corroded and the flapper was actually almost completely gone. I purchase the new valve through Fusick but, I am struggling with the installation. The Chassis Service Manual has pretty vague directions. Not to mention it appears some specialized tools are being called out that I do not have at my disposal. If anyone has replaced theirs I would appreciate some advice on the process. The car is a 69 400cu in.

thanks
Sean

D. Yaros

What is the problem you are having? The install is pretty straight forward as a rule. Not certain on you application, but usually the weight arm goes toward the firewall.

Boilerz25

Dave,

The main issue is removing the existing shaft which appears to be practically fused to the manifold (will check this weekend to be sure). The other part is the initial flapper orientation when cold. I know that the flapper should be oriented then spot welded to the shaft. Does this valve function like a choke (cold/closed, hot/open)?

thanks
Sean

droldsmorland

I remove the whole assembly and weld the holes closed. Also installed the riser crossover block off plugs in to my intake (welded). All in the name of performance and to lessen heat soak hard start issues. With your location Id think youd want to do the same to decrease the heat going to the intake and carb. Just my 2 cents.

oldcutlass

x2, the heat risers had always been problematic and they would stick closed causing more problems than they were worth.

Boilerz25

I think I like the idea completely. Just wasnt sure if there was real value to having it. Consider it done.

Thanks
Sean

D. Yaros

You have been properly advised : Not worth time/trouble. Remove the flapper, weld it open, whatever.

To answer your specific question, yes it is like a choke; cold = closed and warm = open.

MDchanic

x3.

If you run your car a lot in sub-zero temperatures (sub -17.7 for you folks north-of-the-border), then the heat riser can be a real help in smooth running and warm-up.

For the rest of us, who no longer drive these cars in the dead of winter, it's just another thing to go wrong.

- Eric