1925 Maxwell/Chrysler won't start

[Mark Gregush]

Many cars have intake cast the same way in that era and later, such as the Ford Model T. Chevrolet used 2 cast in runners for the intake on one side and a single exhaust port on the other till 1927, then added one more exhaust port on the 4s for on the heads. Dodges 4 exhaust on one side and a single intake on the other.

To add, those steps in the ports in the block would have at one time held gland rings to help seal and keep the manifolds from warping. Except a 3 month window in 1929 or 1930, Ford used them in all 4 cylinders engines from 1908 to 1934.

You will note I am skipping the crack question, but for me, I would live with it.

 

Edited January 14, 2022 by Mark Gregush (see edit history)

[Max4Me]

2 hours ago, Mark Gregush said:

You will note I am skipping the crack question, but for me, I would live with it.

 

Thanks for the info, Mark. Leaving the crack alone crossed my mind. I’m just concerned it will continue cracking until I have two pieces. Although, at my age, by then it will be someone else’s problem!

 

It always amazes me how early engineers designed things and how they have evolved over the years.

[JFranklin]

4 hours ago, Mark Gregush said:

 

You will note I am skipping the crack question, but for me, I would live with it.

 

I agree, but would do what I needed to stop its travel if possible.

[Max4Me]

5 minutes ago, JFranklin said:

I agree, but would do what I needed to stop its travel if possible.

This is my fear, keeps going until I have a two-piece manifold. I just talked to a friend of mine who welds. He said Muggy weld SSf-6 56% silver solder will work really well. Read up on it and it sounds perfect. Has anybody had any experience with this stuff?

[JFranklin]

Would he drill the end of the crack to stop travel and then weld? I have heard of doing that.

[Bloo]

2 hours ago, Max4Me said:

This is my fear, keeps going until I have a two-piece manifold. I just talked to a friend of mine who welds. He said Muggy weld SSf-6 56% silver solder will work really well. Read up on it and it sounds perfect. Has anybody had any experience with this stuff?

 

I think that's a terrible idea. If that were a newer engine it would melt for sure. Could you get away with it on a low compression low horse power engine like a Maxwell? Maybe, but I would bet against it. I think it is going to make things worse. I recall the time in my teens I re-bushed a heat riser shaft in brass, and found the bushings completely missing less than a week later. 56% Silver Solder has a lower melting point than brass by quite a bit.

 

It may be tough to find, but you should be looking for an undamaged manifold.

 

Cast iron is extremely difficult stuff to weld. Also, not all cast iron is the same. Exhaust manifolds are more difficult than a typical cast iron part. Many cast iron repairs today are done by pinning. I don't know if that is practical on on a Maxwell exhaust manifold, but it is worth looking into.

 

Once repaired, an exhaust manifolds expands and contracts with heat, sliding (we hope) around on the block (or head) a little as it heats and cools, because if the expansion and contraction motion is restricted it just breaks. That's how a lot of them get broke in the first place. Then, there is an exhaust pipe attached like a big lever that is also trying to break the manifold.

 

This thread looks like a success story. You might get in touch with Paul S and see if he can fix it.

 

 

 

[Mark Gregush]

Ok I am far from being an expert on welding, but welding or brazing a cast iron block is one thing, the exhaust manifold is a whole different kettle of fish. Years of expansion/contraction and carbon impregnating the material, make for a hard to repair piece. As suggested above, find the end of the crack and drill a small hole. That should help keep the crack from growing longer. You could tap the hole and install a bolt, then cut off flush. Clean the surface and use high-temp JB Weld as a surface patch over the crack.

I just pinned a Model T block water jacket. Years of rust left areas where I was working, rather thin. One area, about an inch long, had the pin drop out and couple that spined when drilling the next one. Not fun, and still hoping they hold.

On page two of link above, there are a couple of important notes, pre-heating and clamping the manifold down.

 

[Max4Me]

Thanks all for the amazing information about fixing a cracked exhaust manifold. After so much reading and research, it sounds like repair is really out of the question. When I originally saw the crack it really looked like a scratch it is so fine. However when I removed the manifold I can see a similar 'scratch' on the inside, but it isn't as long (figure that out), so I'm fairly certain it is just a hairline crack. At this point I'm really leaning toward pinning and then leaving it alone! After dealing with that, I still have to figure out why it won't start.