m151 nos cylinder head
 

Hi, i am looking for a nos cylinder head assy for a m151A2. found my rear exhaust flange was broken off and bolt snapped in the head holding the other side of the exhaust manifold. Any leads appreciated.
cheers, john

Can you not extract the broken bolt?
TNJ Murray would likely be a good bet for NOS M151 parts

Roses surplus up in Saskatoon used to have NOS heads back in the early 90s. Not sure if maybe Dave Good up in Edmonton ended up with them.
But I have to agree with Chris. Changing the head will be as much or more work that extracting that bolt, although by the time you get the intake off you may have more than one broken.
I usually place a washer the same size as the broken bolt or stud over the stud and fill the hole with mig weld. Then I put an oversized bt over the washer and weld it to the washer/stud assembly. As it cools, start to work the nut back and forth. If you shear off the washer/nut, then repeat the operation. It is very few broken bolts that have not resulted in successfull extraction using this method.

Hi Rob, that is a great idea. The flange on the lower side is broken, pretty sure i cannot repair that. Roses was a great place to snoop, found it way too late then they closed.

Hi Chris, u are correct but the lower flange is broken so i cannot mount the bolt to it.

If you don't find your NOS head, I do have a couple core engines here. But they would have to wait for warmer weather just in order to get the tarp off them.

hi Rob, thanks. here is a pic of my issue.

If the engine is already out, take it to a good welder that can weld cast. Build it up, drill and retap the hole.

Bob Phillips near Guelph had a stash of M151 parts he got from Fort Drum. He was doing some yard clearing last fall when I bought a complete powerpack, a stripped block and a crankshaft. I was the cause of major traffic delays on Hwy 401 as I trundled along at just over the speed limit.

It might be worth a road trip with an empty pickup truck!

Terry

Hi John,
I am with Rob on this one.
Unless there is more to this than meets the eye, it can be repaired.
You need to find someone who can do cast iron.

Be sure not to snap off one of the remaining bolts when taking off the manifold, as these heads are notorious for that problem.