Very bad sound in engine...

[PatS....]

I went out and counted my horse shoes after the American/Canadian Challenge..still got all of mine..

Ya...but did you count all your marbles??? :eek:;)

[Alshere59]

Hmm if there was a way for a fifty fifty as to who is right with there diagnoses this could be a good chance to raise money. Half going to his car repair the other half to the Forum.

Place your bets anyone... Almost like horse racing you just bet on your favorite comment if you dont like a 50 50 suggestions.

Edited April 26, 2011 by Alshere59
Yes I know no reason to play other than who has it figured it out

[BobT-47P15]

Maybe that's where Tim's marbles went......into the engine.

[bamfordsgarage]

Well, that was interesting. Sure glad you all encouraged me to pull the head...

[greg g]

Whadja find???

[P-12 Tommy]

Now he's messin' with us.

Tom

[Roger the Dodger]

Come on, give.

[Andydodge]

All 7 pistons are fine..................lol...........come on, even down here in Oz we are waiting...........whats the verdict.............lol...........andyd

[Plymouthy Adams]

now for a word from our sponsor............

[bamfordsgarage]

It sounds like you guys want the whole story. No problem, happy to oblige.

I'll report back soon once I take new compression readings on #2 and #3. Oh, and go for a test drive.

[bamfordsgarage]

And the coveted designation "Diagnostician of Dodgian Difficulties" goes to...

Dr. Don Coatney.

Number two piston has some top edge missing and there was a segment of ring hammered into the top, right where the combustion chamber is shallowest and the noise was loudest. The cylinder wall actually looks worse in the photos — there is barely enough surface disruption to catch a fingernail. No idea how much ring is gone, but the photos show the extent of missing piston.

Compression readings this time around were #2, 45-dry/80-wet. #3, 68-dry. I have no idea why #3 was so low the first time around. I had checked it twice. Perhaps a bit of carbon (there is plenty) stuck under a valve. The head gasket looked solid between the cylinders.

The car is back together now, sounding and driving fine. I expect more pieces could let loose without warning and I may not be so lucky next time. So for now it's minimal town driving and a full rebuild in the fairly near future — top, bottom, and perhaps a few subtle enhancements.

Thanks again to everyone for your contributions and encouragement.

Edited April 27, 2011 by bamfordsgarage

[1940plymouth]

Good to hear you got her back together and running for the time being, sure hope it works out for you the rest of the driving season.

[Young Ed]

Could be a piece of carbon or perhaps a piece of piston/ring made its way over to that valve. Do you feel better with the mystery out of the way? Anyone know where this is from: "and now you know and knowing is half the battle"

[Joe Flanagan]

I would guess that the damage was just a result of age and wear, though I've read that advanced timing can sometimes cause this. I think James Curl had a thread where he drove a long distance across Texas and broke some top rings and attributed it to his timing being too far advanced.

[P-12 Tommy]

Glad you found what it was. Hopefully nothing will come loose before you tear it down.

Tom

[TodFitch]

Glad you found what it was. Hopefully nothing will come loose before you tear it down.

Tom

I'd schedule a rebuild ASAP. Back in the 1970s I had this happen to me on my 1933 and tried to nurse it along (I was 300 miles from home). In my case, the second time the noise happened the bit of ring sitting on the top of the piston caused the piston to rock enough to break the piston skirt. I was lucky and stopped it before more damage occurred but I can imagine that a rod through the block could easily have happened.

[Plymouthy Adams]

by looking at the cylinder, this condition has existed for a good many miles...the clean look at the area of the piston land failure and the ultimate release of the piece of ring voiding the sealing issue of the top ring show the action of scrubbing over the many miles that it took for the deposits that are now below this land but yet above the lower rings to build up...as this ring is now taken on the function of the top compression ring..

[bamfordsgarage]

Tim — I'm thinking maybe what we had figured on Saturday as a carbon chunk later blown out of the cylinder might instead have been the piston land failing and getting blown out of the cylinder. It was a duller and quieter ticking, as one might expect from aluminum. That would put the distance from land failure to ring failure at about 250 miles.

Tod, I agree. The timeframe still looks like July and I will try not to drive the car (much) in the meantime..

[Don Coatney]

Glad you found the problem. I have seen this damage in several high mileage Mopar flathead engines. Pictured below is the ridge at the top of the cylinder in my original engine. Tim Adams can verify this as he has my original engine. Looks much the same as your ridge and I could also barely catch a fingernail. And if I recall my oil pressure was much the same as yours very low at idle and 30 or so at speed. I think you have worn bearings but I have doubts you have spun a bearing or had a bearing insert double up on the top side. Oil pressure is a measurement of resistance as in how much resistance there is in all bearings. If an insert had traveled from the rod cap to the rod there would be no resistance and no oil pressure reading. As has been suggested you should do a major rebuild in short order.

What do you have in mind for enhancements?

[greg g]

Just thinking that made it up Pikes peak in what was likely pretty near that condition is a testament to the work that these engines will do inspite of problems.

[Plymouthy Adams]

Chris..remember..no one is forcing you to paint the engine..it could be rebuilt and easily still pass for old original....only it will be clean patina..

[T120]

Just thinking that made it up Pikes peak in what was likely pretty near that condition is a testament to the work that these engines will do inspite of problems.

..I chuckled when I saw the photo of the old Dodge parked next to the high tech Caddy in camo at Pikes Peak..

[Joe Flanagan]

Could this be the start of the advancing line in the sand for Chris?

[bamfordsgarage]

Don "What do you have in mind for enhancements?"

Joe "Could this be the start of the advancing line in the sand for Chris?"

Jeez I hope not. A little more power would be welcome, but I will get that from the stock rebuild of a tired engine. Beyond that, I understand the crank/rods/pistons from Canadian DeSoto/Chrysler engines will fit in my dirty old block after a 1/16 overbore. Jerry is agitating for this approach. If I could find a set of these in good shape at an attractive price then maybe. Alternatively, I have read up in back threads about shaving the head a bit to improve the C:R — this is often done in Model T Ford engines whereby the C:R can be bumped from 4.25:1 to 4.75:1 with a 0.120 shave. Skimming the head is something that could have been done in the day and allows reuse of more original parts... that's more my style.

Don't see it going much further than that. Comments always welcome.

[thrashingcows]

Anyone know where this is from: "and now you know and knowing is half the battle"

G.I. Joe...A real American Hero.....The cartoon version from the 80's.