The Stovebolt Site Forums The Shop Area Engine Shop Split exhaust and manifold heat

I replaced the stock exhaust manifold on my 235 with twin fentons and lost the automatic manifold heat as a result. The truck has stalled twice due to (I think) carb iceing shortly after start up. (When hot, it runs fine).
Here is my solution and please let me know if it is really stupid.
I made a 3/32 thick aluminium cover for the base of the intake manifold that seals the void below the carb.
My plan is to plumb two 3/8 " compression fittings to the plate at the base of the intake manifold and run two 3/8 aluminium lines to the heater intake and return outlets on the water pump.
That should provide 50 degree water under the carb when cold (18 degrees above freezing) and 180 degree water when the engine is fully warmed. (which should be about the temp of most of the engine.
Do you think this will cause vapor lock problems at the high end or some other problem that I might have missed. Any suggestions are welcome.
Thanks Mike

I did basically the same thing following advice from a member here - thanks 4onthefloor! I used a thermostat housing and water pump from a 261 and ran the by-pass thru the intake which I made out of 5/16" brake line. I made the plate for the bottom of my intake out of 4" x 4" piece of 5/16 flat bar. Here are some pics http://community.webshots.com/album/360111285YfkRkF

Bigmacdaddy;
You are a master craftsman! I hope do do half as well.
Mike

I wouldn't go that far! I'm a shadetree mechanic at best. The stuff I do is usually done with help from the guys here and I am fortunate to have a neighbor who is an ace mechanic that shows me how to do this stuff. The main point is, if I can do it, anyone can! My real job (beer plumber) does involve a lot of fittings and making sure things don't leak and that definately came into play on this project.

Mike, you're right on target but you need a heavier target. Make the cover plate from 1/4" or heavier material so you can drill and tap for 1/4" NPT. The 3/32" alum is much too thin and harder to seal.

You can also buy this part from some of the vendors.

Nice job bigmac, I may have to rig up something similar, I don't have a fenton manifold. I split mine myself. I cut the factory heat riser flap out as it was froze up. Should'a left it in I guess, but that's one neat lookin' piece of plumbin'
resto44

I'm just about to start building a 261 with help from my neighbor and you guys or course. I'm thinking of having my original manifold split and using the stock heating set-up. I have put it on a shelf since I put the fentons w/ the 235. This way I can build all the way to the exhaust pipes while my truck is still usable. On the other hand, I think my plate and lines will match the Edelbrock 2 x 1 I will be using. Also, the Edelbrock is aluminum and will heat up faster than my stock intake does with water. Hmmm...Decisions, decisions....

Hey Mike, I almost forgot. You may already know this, but fitting your manifolds and heating components is SO much easier if you do it on a mock-up head on a bench. Just one more thing my neighbor taught me.

Hey bolters, what do you think about making a offenhauser intake water heated.My only concern is the two plugs that are on the bottom of the intake.I think it is possible they will leak water.Whats your thoughts,i am providing some links to a few photos.

offenhauser 2 x 1 intake
http://img221.imageshack.us/img221/5571/offenhauser9wv.jpg

offenhauser pic #2
http://img221.imageshack.us/img221/3931/offenhauserpic21no.jpg

offenhauser plug picture
http://img353.imageshack.us/img353/3027/plugpic3oz.jpg

Thanks again !!

Use black RTV for a sealant. There is a string of posts under the topic, "heated intakes" from last April, 2005. Good info there.

Take bigmacdaddy's advice, seal the plugs and search for old discussions about "Offenhauser" intakes.

I have a water-heated two-carb Offenhauser on a 261 that has never leaked BUT other people have found that those plugs do leak.

Tim

Thanks, i will do the search, i was getting too tired last night to do so.Thanks again!!!

This is a permanent fix for any leaking bottom plugs on the Offy 2x1 or 3x1 intakes.

If I done this link below correctly,(??it's my first try), the pictures tell the procedure.

I have a few of these slugs already punched out of the correct size aluminun. If anybody needs a pair, just e-mail me and ask. There is no charge for them, as long my supply last.

http://community.webshots.com/user/OldFartEd