Engine disassembled...got bad news

[47heaven]

Stopped by the mechanic's shop that is rebuilding my engine today and he told me that pistons were pretty worn and the cyliner walls were already bored at 60. He said that that was pretty much it's limit and that it wouldn't be wise to bore them anymore. He mentioned that the engine had signs of being rebuilt at one time, but we couldn't tell about how long ago that might have been. By the time I had seen the engine, he already had it disassembled and hot tanked. He said that there was a bunch of caked on rust in mud in the engine (which was to be expected) and said that it also attributed to the over heating problem.

Anyway, he told me that he was able to locate two other engines in town from a '47 P15 and the other he's not sure what year. He's going by this afternoon to see if the engine is useable or not. I really don't want to go back to the P15 engine because I heard it was less horesepower than the P26 that I already had in the car. If the P15 engine that he's going to look at can be used, what can be done to it to give it a little more "ooomf" than the original 95 horsepower that it originally had.

Any ideas or feedback?

Darin

[anthonyb]

You might have him look into boring it out even more and then sleeving the cylinders back to something you can live with. That's gotta be cheaper than buying a completely different engine. I had one cylinder sleeved in my 41 P11D and it runs like a top with no problems from the procedure.

[james curl]

I believe that Terrell Machine in DeLeon, Tx stocks .080 oversize pistons. I would guess that it would take a .080 or they would not make pistons that size for them.

[martybose]

As I have previously mentioned, my 230 block was in exactly the same condition. We used an ultrasonic tester taking measurements at top, center and bottom of every bore with a measurement every 90 degrees at each height. That's 72 measurements, and found that it would take an .080" overbore easily.

We actually wound up investigating modern ring materials, and chose a metric ring set used in Toyotas, then had flathead pistons custom made to use them. Wound up as .072" over, 247 ci engine.

Marty

[Tony_Urwin]

In addition to the oversize pistons, you could also swap in the crank and rods from a 230. The longer stroke will yield even more horsepower. I think Blueskies stroked that beautiful flathead in his Plymouth.

[Young Ed]

I think Tony has the best idea. Swap the crank and rods from your 230 into a p15 block and get your HP back and a matching #s engine. If you do that and reuse the p26 head I think you should end up with the same power. As far as sleeving the machine shop we use gets 100 a hole for that. Doing all 6 would be pretty spendy.

[Allan Faust]

Mine was bored at least 90 over just recently..... no problems....lotsa metal left.... (but then again, it isn't in the car yet.... but I'm not worried in the least).

Allan

[55 Fargo]

Allan, the Canadian engines all used the same block for 218,230, 251,265. I know you know this, on our engines there is more room to bore out, especially with the 218 and 230, they had a smaller hole than the 251 and 265............Fred

[BobT-47P15]

Yes, I think they say these engines will go 90 over without being a problem. I'm sure each engine builder has his set of beliefs about how far to bore.

[Alexander]

One other tought...

You can also sleeve the cylinders and then put original size pistons.

[Plymouthy Adams]

Most the time on these engines, the original pistons are in such worn condition especially in lower skirt (cracks) and in the upper ring lands that cleaning and reusing is a risk..so if you should be able to resleeve new pistons should be purchased of standard bore. Due to cost and other options I nix this idea at the moment save it as last ditch effort when you get ot be up in age and still driving this jewel. However their is plenty of metal left in the block..bore to the closest standard oversize using the 230 slug and rods and get some extra umph out of the engine..

[Normspeed]

FWIW, books can be misleading on this stuff but my 46-54 service manual says Chrysler only sold replacement pistons up to .060 over. That said, I'd still probably think about going with those .080s if I could get the correct rings and convince the shop to bore it that far.

Second choice, the idea of using a P15 block with your 230 rods pistons and flywheel sounds good, gives you a P15 motor number and 230 performance. That would depend on how much buying the motor, paying for extra labor, etc might add to your cost, and the rebuildable condition of the P15 motor.

Darin, if you have that service manual, take a look at the part on cylinder block/pistons, around pg 135.

[Jim Saraceno]

Another option is to buy another motor. Those things can be had for a song. They were made by the millions being used by Plymouth, Dodge, marine, industrial and military applications. Plus a lot of people who buy these old cars want to take the flathead 6 out and drop in a small block chevy.

When I rebuild my engine, rather than pulling the engine and rebuilding it, I bought another engine for $75 and that included the tranny, manifolds, carb, fuel, water, and oil pumps... the whole tamale. I probably overpaid for it at that price.

I then rebuilt that engine and just swapped them out when I was finished, now I have a spare engine, tranny and all.

You see them come up on Ebay from time to time and most of the time they can't sell them.

[PatS....]

They're rare as hens teeth up here. The crusher got 'em all many years ago

[Jim Saraceno]

George Ashe told me he would sell me a block for a '35 for $150, I'm sure he would have more later model engines that might even go for less. Heck, if you wanted to come down to St. Louis to pick it up, I might be able to get you the other engine that the guy had.

[55 Fargo]

Pat, I remember when you were looking for a flathead, they seemed scarce, then you found the one you have now. I now know where htere are at least 10 of these engines in a 10 mile radius of where I live, I even have 3 of them, 2 x251, one runs, one is eized, and my 218 big block in my 47 Chrysler, I spoke with a large engine building company, one guy has been with them 30 years, he told me until about 12 to 15 years ago, they always kept 15 to 20 Chrsler flatheads in stock rebuilt, mostly 251 or 265 industrial types, these are truly a great engine, sure glad I decided to keep my car with a flattie instead of a SBC.....................Fred

[47heaven]

Ok guys...first, thanks for all the good feedback. I copied and gave him all that you guys mentioned about boring the cylinder walls to .080, but he still doesn't feel comfortable about it...concerned about walls being too thin and more heating problems down the road. (I don't want to push the issue with him because he could turn around and tell me to take it to you guys, instead, not that he would, though.)

So, anyway, the good news is that we found a 1950 Plymouth engine that looked to be in used, but in good shape. Next too it was a Plymouth transmission, and get this...with overdrive! The woman sold them to me for $300. She just wants to get rid of the pile of Plymouth stuff she has...most of it from a 1949 and 50 Plymouths. I told her that I would take pics of the stuff and post it here and then any of you guys that are in need of parts can contact her and do your negotiating, then. She has a rebuilt P15 engine ready to drop in. I think she wanted something like $800 for it. She also has seats, dashboard, and a couple complete grilles for a 1950 Plymouth. I'll get more info and pics up later this week. Like I said, she's not looking for big bucks...she just wants to get rid, but at a fair price. Oh, if you live far from Upland, California, where she is located, you will have to make your own arrangements for shipping because she doesn't want to mess with it.