Does anyone know where I can get a new exhaust manifold heat riser valve for a '61 235 engine. I haven't had any luck with the online parts catalogs so far. Appreciate any help......thanks, Fantm2
[updated:LAST EDITED ON Oct-31-04 AT 08:49 PM (CST)]If yours is frozen/rusted in place you can try freeing it by repeated applications of Mopar rust penetrant, (FKA Mopar heat riser penetrant Mopar part #04318039). IMHO, it is the only thing with Mopar written on it that ever worked the way it was supposed to. A little gentle tapping, and some heat from a torch will help the process along. If this doesnt work, you are likely going to have to find another exhaust manifold, with an operable riser. Not aware of anyone making new valve assemblies, but possibly a machine shop could figure how to press the old one out and make a new one for you? Dont forget to replace the bi-metal spring that opens and closes the valve. HTH.
I can get you a 61 heat riser, but the only thing I have is one off of a 283 or a 327 engine. Those are V8, while yours is a 6cyl. I'm no expert, but do you think that would work? If so, I'm asking 37.00. Let me know what you think: iliveformyking@hotmail.com Thanks, Stephen Hardy Hardy Chevrolet & GMC Restoration parts
I'm 99% certain the riser for a V8 and a six arent even close to the same. But I have been wrong before. The riser on the six is a butterfly type valve on a shaft, inside the manifold, with large counterweight on the front end and a bi-metallic spring on the other. BTW, the spring is Chevy Duty part #89-425.
I did what you suggested only I used everyday penetrating oil. In the process, I learned a lot about heat risers. For one thing, the counterweight is not just pressed on, but has a 1/8" pin through it, but if you hit it hard enough, it-will-break. No sweat there. I finally got the entire valve out, and cleaned up the rod and it turns freely now. Part of the end where the spring goes was broken off, so I turned the rod 90 degrees and sawed another slot in it. Now all I have to do is get a new spring, set the thing up, and re-weld the valve plate to the rod. Thanks for your reply!
