48 Chrysler No compression

[R Walling]

I have the head off and I wonder if there is any way to make sure the rings are free other than penetrating oil and turning it over many times?

 I have also used acetone and ATF.

Thanks,  Roger

 

Edited June 14, 2021 by Roger Walling (see edit history)

[37_Roadmaster_C]

As far as I know there is no way without popping out the pistons and checking when they are free.

[TerryB]

I’ve been waiting to see a response to this.  Never had to deal with this on a car. Did the ATF trick in a Vespa scooter and it worked good enough to get it running.  My totally untested idea would be to pour Marvel mystery oil 1/2” deep on top of the piston and see if it stays put after X amount of time. That would test for a measurable big leak.  You could use a turkey baster to suck out the liquid if it’s not leaking ( I can hear the laughing in the background now).  
 

Of course the right way is to pull the pistons as mentioned above but hey, it’s always intriguing to try something new.  

[Guest]

Agreed on the Marvel Mystery Oil.

It's.... well, marvelous for this type of thing.

[Rusty_OToole]

How many miles on the clock? How worn are the cylinders? In other words how much ridge at the top? Did it lose compression because the valves were stuck from sitting?

If the engine is not badly worn and the only problem is sticking valves I would free them up, pour  a little MMM on the pistons, put the head back on and try it. If it is due for a ring and valve job now is the time to do it.

[Guest]

 The engine has only 39,000 on it. 

I cleaned the valves and seats with a 3M pad folded up twice, got under the valves and did the seat at the same time.

 Washed it down with plenty of penetrating oil and blew it out with air.

  I am going to wipe down the cylinders with Lucas, The real sticky stuff. That should seal the rings enough to start with 12 Volts.

 If that doesn't work, an early 392 with a 700R4 and a Ford 8" limited slip will take it's place.

 I really am doing my best to keep it original as a nice survivor.

 

 If it starts, the clunk-a-mantic transmission will be the next hurtle.

 

Edited June 15, 2021 by Roger Walling (see edit history)

[TexasJohn55]

The only ring you can check is the top one. You should be able to rock the piston from one side to the other and see the top ring with a good flashlight. After confirming the ring is not broken then try sliding a .002" to .003" feeler gauge down beside the ring. That is about the extent of it, the others could still be stuck.

Forget the Lucas. It will run or it won't.

Edited June 16, 2021 by TexasJohn55 (see edit history)

[TerryB]

3 hours ago, GregLaR said:

Agreed on the Marvel Mystery Oil.

It's.... well, marvelous for this type of thing.

My father’s starting point with any engine issue was MMO.  He always had a pint can handy.  Sometimes it helped and other times not so much.  Some in the gas tank and some down the carb. I always thought it was the automotive equivalent of giving caster oil to sick people. 

[edinmass]

On 6/14/2021 at 5:55 PM, Roger Walling said:

I have the head off and I wonder if there is any way to make sure the rings are free other than penetrating oil and turning it over many times?

 I have also used acetone and ATF.

Thanks,  Roger

 

Flush the block with HOT evapo or water. Often times stuck rings are from gummed up oil and fuel. Heating the block up to 190 degrees with a pump and bucket heater will soften the petroleum and break things loose. If you have a Stanley Steamer handy, just run a copper tube from the blow off valve through the block. Works like a charm every time. Cold soaking the block will take a few weeks to work..........added heat is the way to get it to run.

 

Edited June 16, 2021 by edinmass (see edit history)

[Guest]

9 minutes ago, edinmass said:

If you have a Stanley Steamer handy.....

 

Ed, we were in lock step right up til this sentence.  😄

[edinmass]

I have used a Stanley to quickly heat a block and get oil past rusted pistons and rings...........you can take the block from room temperature to steam temperature very quickly........the thermal expansion is even and doesn't cause damage. It's messy, smells awful, but it does get the oil past the stuck pistons. Using the hot water or evapo rust works well also. It's hard to believe how stuck an engine can get from varnish and oil residue. If you can get the temperature up to 150-180 degrees for a few hours, it soften it up and usually will turn. 

Edited June 16, 2021 by edinmass (see edit history)

[Dandy Dave]

Once you get the valves to seat you can do a leak down test after you get the head installed. This is often done on piston aircraft engines. Best if you get it running first and warm a few times. Dandy Dave!

[60FlatTop]

The pistons that came to rest in the lower, unworn and tighter area of the bore will tend to stick. The ones that sat with the rings expanded at the top of their bores will usually be OK. A compression check on an out of storage car will tend to show half high, half low. Drive it 150-200 miles and check the compression again. The rings will free up it the engine wasn't shot to begin with.

 

Worse is the long term storage that was unintended and the car left with dirty, slightly acidic oil sitting on the bearing surfaces. Old oil can etch a thousandths of an inch of bearing material that will wipe off on the first start. She'll rattle before you get the rings free.

 

The head is off. Drain the oil and the pan becomes an access cover, makes it easy to be sure.

[JimKB1MCV]

  I guess my reading comprehension must be disintegrating due to old age, I was thinking the head was removed to get at the sticking valves, not that the engine was stuck.

 

  I need to go back and read the start of the thread.

[Rusty_OToole]

20 hours ago, Roger Walling said:

 The engine has only 39,000 on it. 

Should be good for another 50,000 with reasonable care. All parts are available, they are cheap and the engine is easy to work on if it is a six cylinder. The straight eight, parts are scarcer and of course, engine is more complicated.

I wouldn't think of changing the engine or trans. They may not be the latest thing but work better than you would expect, especially if you appreciate smooth, quiet, trouble free performance.

If you are not familiar with the Fluid Drive system it is a unique setup, a cross between a manual and automatic trans. Like an automatic but with a clutch pedal. Simple and rugged, usually trouble free and most problems can be solved easily for a few bucks and a little work. There has been much discussion on the proper driving technique, which is pretty simple once you know it but not easy to work out on your own. Do a search for Fluid Drive in the Chrysler section and lots of info will pop up.

 

[Rusty_OToole]

If you don't have a Stanley Steamer would an inline block heater do?

[JamesR]

38 minutes ago, JimKB1MCV said:

  I guess my reading comprehension must be disintegrating due to old age, I was thinking the head was removed to get at the sticking valves, not that the engine was stuck.

 

  I need to go back and read the start of the thread.

 

Jim, I think there are two different threads on this one car, and they are close together in the same forum. Don't know if that's what you're referring to, but I thought I'd mention it because I sort of wondered about that, too.

 

Nice looking old Chrysler, Roger. Best wishes with the project.

 

 

[TexasJohn55]

On 6/14/2021 at 4:55 PM, Roger Walling said:

I have the head off and I wonder if there is any way to make sure the rings are free other than penetrating oil and turning it over many times?

 I have also used acetone and ATF.

Thanks,  Roger

 

 

1 hour ago, JimKB1MCV said:

  I guess my reading comprehension must be disintegrating due to old age, I was thinking the head was removed to get at the sticking valves, not that the engine was stuck.

 

  I need to go back and read the start of the thread.

 

[JACK M]

On 6/15/2021 at 4:32 PM, Roger Walling said:

an early 392 with a 700R4 and a Ford 8" limited slip will take it's place.

 

That would be after you change out the front clip.

Steering box will be in your way.

MII here.

 

Oh yea, ditch the 700R4 and get a four speed,