4.2 straight 6 engine stuck?
#1
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my barn find car that has been stood for the last 20 years has a stuck engine. I have pulled the starter motor out to make sure it wasn't that. For the last 4 weeks I have been feeding the bores with various penetrants. The first 3 cylinders from the front of the engine drain away, the last 3 dont. The engine feels solid when I try to turn via the crank. Is this how an engine with stuck rings behaves or could it be something else. 1976 4.2 automatic. Thanks in advance for any help
#2
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Thats how they will feel. The rings will basically be rust "welded" to the bore (dry liner in this engine), and nothing will move, period.
An engine rebuild shop would take the bottom off, and using a "Jackhammer" style tool, basically drive the piston and dry liner out through the top, sacrificing the piston and liner. New style "stepped" liners are recommended for this engine as they have been known to "nip up" and drag a liner downward.
NOT what anyone wants to hear, but thats the way it is.
I used one of those tools back in the late '60's, when as an apprentice, I had to dismantle a Stutz Straight 8 that was well and truly seized. Got it apart, made pistons, modified some other brand liner, and all sorted.
In this case, another engine would be more economical in MY opinion. Screws the matching numbers, but there are number and letter punches out there, so not all doom and gloom.
An engine rebuild shop would take the bottom off, and using a "Jackhammer" style tool, basically drive the piston and dry liner out through the top, sacrificing the piston and liner. New style "stepped" liners are recommended for this engine as they have been known to "nip up" and drag a liner downward.
NOT what anyone wants to hear, but thats the way it is.
I used one of those tools back in the late '60's, when as an apprentice, I had to dismantle a Stutz Straight 8 that was well and truly seized. Got it apart, made pistons, modified some other brand liner, and all sorted.
In this case, another engine would be more economical in MY opinion. Screws the matching numbers, but there are number and letter punches out there, so not all doom and gloom.
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Doug (08-22-2020),
Greg in France (04-26-2022)
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Grant Francis (08-22-2020)
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Circa 1958,built a T Speedster from junk and cast off parts.
I a "rebuilt short block. well, it was the sof a firehad ithe open f
Key board issue??
Using a bloclk of wood and a sledge, i drove the pisotons out. As they were iron, they remained intact.
Good babbitt!!!! Honed the bores, did a valve job, fitted other pistons and new rigs. it ran great !!!
Carl
I a "rebuilt short block. well, it was the sof a firehad ithe open f
Key board issue??
Using a bloclk of wood and a sledge, i drove the pisotons out. As they were iron, they remained intact.
Good babbitt!!!! Honed the bores, did a valve job, fitted other pistons and new rigs. it ran great !!!
Carl
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Grant Francis (08-22-2020)
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Grant Francis (08-22-2020)
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In my experience, if an engine is seized up then you can bet the cylinder walls, pistons, and rings will be shot. At the end of the day it always comes down to a full engine overhaul....so why even bother trying to un-seize unless a full overhaul was in the plan to begin with?
A good used motor is a great alternative in this case.
All "IMO"
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Cheers
DD
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Greg in France (04-26-2022)
#9
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Had the same issue with my Series 1. Tried for weeks with all sorts of penetrating fluids. Would not budge.
Ended up buying another Series 2 for $500. Turned out to be a "blessing in disguise", lots of useful spares, interior, fuel tanks, front brakes (4 piston) etc. plus of course the engine. The previous owner paid $7000 for the car, bought it "sight unseen".
I thought at first it would be a shame to part-out the car, until I nearly fell through the trunk floor due to rust!
Plenty of Jag "stories of woe" out there it seems!
Ended up buying another Series 2 for $500. Turned out to be a "blessing in disguise", lots of useful spares, interior, fuel tanks, front brakes (4 piston) etc. plus of course the engine. The previous owner paid $7000 for the car, bought it "sight unseen".
I thought at first it would be a shame to part-out the car, until I nearly fell through the trunk floor due to rust!
Plenty of Jag "stories of woe" out there it seems!
Last edited by redtriangle; 08-23-2020 at 05:11 AM.
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Greg in France (04-26-2022)
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Circa 58, I built a T Ford speedster from discarded junk, I got a short block for free that had been rebuilt, so he said. but spent a few years in the bsrn yard Froznen stiff. My tools to remove the stuck pistons was a chunk of 2 x 4 and a sledge!!1 got them out, a bit worse for the wear. but, Yahoo, great babbitt in the rods and mains. it became the engine tht I installed and ran great..
Carl
Carl
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LT1 jaguar (04-26-2022)
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