john hess

53 pon l8 heat riser repair help needed

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Hello everyone. I an looking for help on my l8 heat riser. I had brass bushings put in my manifold. Shaft turns fine. Need to weld flapper in place at old weld marks. What I don't have, and need, is a photo or description of the proper position of the counter weight in relation to the spring slot on the shaft. Any help here would be appreciated. Thanks in advance, john

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There is surprisingly little info out there. Here is the Early Times Chapter's page on heat risers, just in case you haven't already seen it. It does not answer your question.

 

http://www.earlytimeschapter.org/manifoldheatcontrolvalve.html

 

And another recent thread about a 1949 l6 that I suspect uses the same heat riser parts as your 53. Unfortunately, there is no difinitive answer there either, but there are some pictures.

 

http://forums.aaca.org/topic/293664-engine-hesitates-and-back-fires-while-driving

 

My l6 (1936) is similar, but unfortunately the weight and spring are reversed front to back compared to the later cars, and I don't think any angle information from my car would be valid, even though many of the parts look the same.

 

How much information can you get from the cut welds? If you can see how the slotted shaft was in relation to the plate, and get that correct, the weight will be easy. I guess theres no flat to locate it? No mattter. The weight should be up on top when cold and swing down as the riser moves to hot position. If it is a half moon shaped weight like in the 49 l6 thread, when cold it should be curved side up, flat side down with the flat side parallel to the ground. As it warms it should swing in toward the engine block, and end with the flat side perpendicular to the ground, and the curved side in toward the engine. This is only an approximation, because the shaft does not move quite a whole 90 degrees, but get it close to that and it will work.

 

 

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Bloo, thanks for the reply. Yes the other posts show some of what I am looking for, but not exactly. So l guess there will be some trial and error adjustments. But that's the fun part of these old cars. No computers here. This is a frame up restoration of a family owned barn find. It was my wife's great grandfathers car from new that was put in a garage in 1976 and forgotten till 2009. John

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Bloo thanks again. Did some trial and error. Think I got it where it should be. Works fine with torch heat. Opens and closes as it should. One other thing I didn't ask was, is there any preload on the spring? I have 1/2 revolution on it now. should be enough to hold for exhaust flow since this isn't possible on bench test.  I realize this isn't stock spring but it works till I get original style. Here are some pictures so far. The small wire you see is just some welding wire jammed in to keep flapper from spinning while testing. Will weld in place when I'm happy with operation.

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I would like to let everyone know that this is my first attempt at a restoration. It is being done on a very very low budget, as I feel I am like mo

Edited by john hess
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I would like to let everyone know that this is my first attempt at a restoration. It is being done on a very very low budget as I think I am like most people who first get started. I am doing this in an unheated old drafty barn which I share with numerous critters. my skills are limited, but I feel adequate for the task at hand. This is certainly a learn as you go experience, and I enjoy every minutue of it. Enough said for now. Here are a few pictures of my attempt at rust repair in trunk floor.

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7 hours ago, john hess said:

One other thing I didn't ask was, is there any preload on the spring? I have 1/2 revolution on it now. should be enough to hold for exhaust flow since this isn't possible on bench test.  

 

That sounds right. I think my 36 has about a half turn of preload and I will look when I get a chance. I gather the springs varied a lot by year, but if it closes when cold and opens with a heat gun, and the weight is in a position to hold it open while the spring is slack, I think you are done.

 

The engine and chassis is looking great. The rust repair is looking good too!

Edited by Bloo
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