No metal is missing from the damaged piston, so matching it to another piston should be easy.
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The forged CJ pistons that went in mine have been fantastic so far. I was afraid theyād be louder because the skirts are shorter but itās like a sewing machine.
But without knowing what her dad did or did not do with the bores, itās hard to recommend subbing parts. If theyāre original cleaned up pistons and not an NOS set then it sounds like what I did 20 years ago, just a hone and re-ring. Itās hard to understand the current state without a pro measuring everything.
Gotcha. So, if Candiece was to weigh her damaged piston on an appropriately sensitive scale it could be compared to the replacement to confirm a match. Makes sense.
Yeah. Same experience with new Mahles in my engine.
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Well, if you mean this part Nick, I did that with my 3.8 while I was adding valve seals. I protected the crank journals with rags and tape and thoroughly washed it all down with kerosene afterwards. Then I installed a set of Hastings cast iron rings but I retained all the shells after a Plasigauge check.
That was the end of my oil burning and fuming problems and the motor was still running sweet 10 years later when I sold the car.
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I may be doing the same with my 3.4 rebuild that I did with my much more experienced BIL. When we were installing the pistons he furrowed his brow and said the replacement rings, Deves, have a reputation for poor seating. Blue smoke on startup that didnāt improve, so the engineās been left static for more than a year while I finish the rest of the restoration and have an opportunity to get the car on the road and attempt a proper break-in. Thatāll be in the Spring. When we did the same job on my 4.2 with pre-ringed Mahles they bedded in instantly, so Iām more inclined if the Deves rings donāt seat to do a light rehone and install new pre-ringed pistons than just a different ring set. Less work and more predictable.
Are the Deves chrome?
No. Not chrome. (Plus 20)
Good: maybe a good hard 100-200 mile run might seat them.
Thatās what Iām hoping. (Iām ignoring suggestions to dump a quarter teaspoon of BonAmi into each cylinder while muttering a few Hail Marys).
My problem was similar, the āspecialā chrome rings I bought never bedded in in several years, the cockpit would fill with fumes whenever I floored it, plus I had white smoke on start-up because of the lack of inlet seals (on the 3.8). In fact, like your BIL, the machine shop that carried out my engine balance had expressed concern about the rings I had chosen but I didnāt listen.
So this time, I used a new set of Hastings cast iron rings. I have no idea of the actual mileage on the car but the pistons were original stock, STD, and looked OK. No scores, the grooves were good. I think it was a mistake anyway to use the chrome rings because a hobby car is never going to be subjected to a great mileage, by its nature.
I used a ball hone I borrowed from a machine shop together with a slow heavy duty 1/2" drill and it made a great job on the glazed bores.
Yeah, a lot of those never made a difference to mine, but then they were chrome.
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For chrome rings to work, they MUST be installed into newly-bored cylinders: three times I used them in what looked to be good, ball-honed cylindersā¦ three times I had to eat the jobs.
Yeah, too bad that we had to learn all this stuff the hard way.
Itās much easier for folks now with the information on the net and forums like this.
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The last one of those servings is now nigh onto 40 years ago: it still wrankles.
Maybe Chris Coleman on ebay.co.uk has one for you, he is not expensive.
chriscolesjags@yakoo.co.uk. He restored many engines.
If you give him a little more information about the piston will be fine. So 4.2 STD, compression 8 : 1 or 9 etc.
Frank.
Frank,
Thank you for reaching out as I have yet to find a single piston!
Candie
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Merde: likely gonna have to spring for a whole set.
Years ago (1976) I did the same thing on my '68. It was so severely glazed that it was running through a quart of oil every 200 miles, which necessitated frequent spark plug removal and wire brushing to clear the misfire. Pulled the head and the pistons, ball honed the bore and installed cast iron rings from Hastings. Oil consumption went to a quart every 2000 miles and the exhaust pipes ran a light grey. Key is break in. After installing the rings you need to drive it hard right away. Full throttle 5 to 10 times up to 3500 - 4000 rpm or so in the first drive.
Did you try Siestasun? His name is Jim and when my engine was being rebuilt he told me he had a lot of NOS jag parts.
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