Manifold Heat Control Valve

[52dodge]

My 230ci has a cracked exhaust manifold that sounds like **** and drives me nuts.The guy i got the car from gave me a spare exhaust manifold with the car.Problem is the heat control valve must of froze up up at some point and someone hacked it out.How important is this valve?I only drive my car during the summer in warm weather.Will the motor still perform normal without this valve?Im assuming it will take longer to warm up which would be fine with me.I looked at the heater control valve on my cracked manifold and its not even totally functional.The spring is broken and the valve just flops in whatever position it wants and the car runs great so im assuming the car would operate fine without this valve?

[plyroadking]

I've ran mine for 8 years without a functional valve in my daily driver. its important to make sure that the butterfly valve inside is in the open position.

[52dodge]

im a little confused on what would be considered open position, if the valve is cut completely out would that be considered open? Im confused because i read of some guys putting a blockoff plate between the two manifold halves

[Don Coatney]

Below is how I have my dual exhaust manifild set up. The plate is welded to block off the front half of the manifold thus allowing the back half of the manifold to heat the intake 100% of the time. I would guess that this is considered open. Closed would prevent exaust heat access to the intake. But that is my best guess. It may be the other way around.

 

 

 

[_shel_ny]

Tomato- toe mato

 

 

You want it in the closed position to allow the exhaust to flow freely.

 

 

[52dodge]

so i should sandwich a plate between the two manifold halves to block it off since i have no valve at all?

[Don Coatney]

Tomato- toe mato

 

 

You want it in the closed position to allow the exhaust to flow freely.

Thanks, Now I get it.

[Alshere59]

That is what I did just fabed a plate and put the gasket on the exhaust side. Is the shaft still there or are you missing just the plate? I ask as the shaft may cause an exhaust leak and/or rattle depending how worn it is. That can be removed also and the holes sealed.

 

So some background on the valve. It is there to keep the carb fom icing in spring and in fall. Open it heats the carb and it It closes as the engine gets warm to let the exhaust flow better. For those running headers you can get a plate that allows your coolant to flow under then intake where the exhaust would have bolted up to heat it as well.

As to why some of the pics look different. Some split the exhaust (add another dump to make it have dual exhaust. That is why Dons is welded the way it is it directs the gas to his new dump. Although some chose to actually seperate the two halfs and add another dump. Just a cheaper way to get dual exhaust.

 

 

[52dodge]

the shaft and the plate are missing,sandwiching a thin plate in there shouldn't cause and misalignment issues with the haves should it? Also i read that special washers are used under the manifold bolt heads,where can these be purchased?

[52dodge]

is the valve being stuck in the open position that i hear causes burnt valves?

[Alshere59]

the shaft and the plate are missing,sandwiching a thin plate in there shouldn't cause and misalignment issues with the haves should it? Also i read that special washers are used under the manifold bolt heads,where can these be purchased?

 

No special in washers in mine the gasket should seal the bolt holes. A thin sheetmetal plate souldn't cause any alignment issue.

 

I have heard heat valves stuck open can burn a valve but can'y confirm. 

[Don Coatney]

Yes there are special nuts and washers required for manifold to block assembly. Follow this link and go to page 163 for details.

 

http://mopar.pairserver.com/p15d24ph_forum/index.php?/links/goto/43-1936-to-1948-plymouth-parts-reference-manual/

[greg g]

I have been running mine without a flap, physically removed, shaft holes welded shut, for 12 years with no ill effects. I placed a gasket and a thin piece of stainless sheet with counter sunk screws attaching same to the exhaust manifold. I am running a fenton

dual carb intake manifold, so the two are not physically connected as the stock application is. After all these years I have a slight exhaust leak on the back side of the exhaust manifold but it is so far not noisy, it just

blows a little soot where it can't be seen. I live in Syracuse so operating temperatures are similar to your's.

I have never had an issue driving in 30 to 40 degree spring and fall weather. Like you I don't operate the car in

the winter.

Edited April 9, 2013 by greg g

[52dodge]

thanks for the info greg,im headed to Utica fri with my transmission, a place called Professional transmissions is going to replace the syncros and go through it for me,ever heard of them?

[greg g]

Not familar with many businesses in Utica.  Haven't had to stray from the Syracuse area to get thing done or find things.