I've got the engine out of my '24 touring to rebuild the transmission, the engine has been running fine. There has been no evidence of a manifold leak. It has good compression, 52 - 56 lbs across all cylinders. But while I have the motor out I want to install a Z head. So I've been cleaning up the deck, scraping off carbon and chasing the threads.
I'd like to also lap the valves while I'm at it. But I'm a little leary of removing the exhaust manifold for fear of warping and not being able to get it back on. Is there anything I can do to keep it straight when I take it off? I don't have a spare block to mount it on. Or am I just fretting about this too much. The motor was completely rebuilt about 10 years ago. Is there anyway to tell if this is an original or reproduction exhaust manifold? Thanks.
Here's a pic of the manifold.
Either it is warped or it isn't. Take it off, no worries. Just don't heat it red hot while it is off.
Erich's right. Either it is or it ain't. If they go, you know.
Well, crap. It looks like it is warped. I put a straight edge across the bottom edge of #1 and #4 holes and there is a gap on #2 and #3. It probably was when it was rebuilt last time. There were only 3 rings. #1, 2 and 3 had a ring and a gasket, #4 just had a flat gasket, no ring. Looks like I need to get a new manifold.
Steve - It doesn't look too bad to me; if it will go back on with the glands properly in place in the manifold and in the ports, I'd just put it back on and not worry about it.
Nothing to loose by trying it as it will either fit or it wont. It looks like it should be useable.
Secondly, the new ones are very nice. get a new nut and you wont be sorry.
Being that there was no steel ring in #4, just a flat gasket, it seems the previous owner could only get steel rings in 3 of the 4. This afternoon I've been going through all the spare parts I got with the car so I don't order something I already have. I found 2 new sets of steel rings and copper glands and 1 used steel ring, still with soot on it. I suspect this is the missing ring that was on the car at one time, but he could not get in on the last time the manifold was off. I'll try it and see, but I'm not optimistic. I see a new manifold in my future.
Steve, I have a spare manifold new in the box.
Give me a call.