Assessing an unknown engine
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- Nurse, I think I need some assistance
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Re: Assessing an unknown engine
Well done Rob.
Need to get all the parts out and check the IMS gear wheel for damage etc., but looks like a good engine.
If it helps, when my 3.2 blew the alum grains were everywhere in the engine, oil cooler and all the galleries and pipes, just everywhere. I threw the oil cooler away as impossible to flush it clean and be sure I had.
The pump was full of fine alum gains but looked good, so i stripped and flushed it all out and re-used it. Gives 4 bar at 15000 rpm hot. For 2 years now.
A new one will always be a good thing.
Buy a good set of oil gallery cleaning brushes as you will need them.
What a crap rebuild effort it was!
Need to get all the parts out and check the IMS gear wheel for damage etc., but looks like a good engine.
If it helps, when my 3.2 blew the alum grains were everywhere in the engine, oil cooler and all the galleries and pipes, just everywhere. I threw the oil cooler away as impossible to flush it clean and be sure I had.
The pump was full of fine alum gains but looked good, so i stripped and flushed it all out and re-used it. Gives 4 bar at 15000 rpm hot. For 2 years now.
A new one will always be a good thing.
Buy a good set of oil gallery cleaning brushes as you will need them.
What a crap rebuild effort it was!
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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- Nurse, I think I need some assistance
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Re: Assessing an unknown engine
How can you rebuild an engine without cleaning it and leaving broken piston in it? Pistons changed without splitting the case and they thought they got away with it?
What do you think caused the oil starvation? Sealant or broken piston?
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What do you think caused the oil starvation? Sealant or broken piston?
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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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Re: Assessing an unknown engine
Looks that way - either replaced a piston without splitting the case. Or given the bearings look good, maybe they did a good job of a full revuild, but the chunks were hiding somewhere.neilbardsley wrote:How can you rebuild an engine without cleaning it and leaving broken piston in it? Pistons changed without splitting the case and they thought they got away with it?
What do you think caused the oil starvation? Sealant or broken piston?
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I think I'll know more once I've stripped and cleaned it. It's a bit of a mystery because there are clearly mint condition pistons and cylinders alongside overheated ones. I'm not that familiar with the engine design but the pump seems to be at the front and send oil down a galley towards the back. It's the back which appears to have overheated more. I even wonder if it was run with insufficient oil. Or even if the piston rings were incorrectly specified or badly fitted. They've been fatigued up the sides of the pistons on some, but others are normal.
The crank looks well lubricated though. I'm sure an experienced 911 engine person would know exactly what happened.
One con rod is a different colour to the others.
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1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
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- DDK 1st, 2nd and 3rd for me!
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Re: Assessing an unknown engine
I don't have any experience what the crank bearings should look like. All were seated properly, no rotation. They appear to be mint on the inside.
But on the outside they appear to show signs of oil erosion, which is a surprise to me. Is this normal?
This harks back to when I was splitting the case and I said the through-case bolts were surprisingly loose (but all consistently torqued). Maybe if those were too loose, the oil would pass behind these shells instead of into the crank journals?
Anyway, moving on the crank journals all look mint and measure to 57.025mm which based on a quick search of the Internet is acceptable?
Probably not quite the right tool for measuring it with but I was super careful.
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But on the outside they appear to show signs of oil erosion, which is a surprise to me. Is this normal?
This harks back to when I was splitting the case and I said the through-case bolts were surprisingly loose (but all consistently torqued). Maybe if those were too loose, the oil would pass behind these shells instead of into the crank journals?
Anyway, moving on the crank journals all look mint and measure to 57.025mm which based on a quick search of the Internet is acceptable?
Probably not quite the right tool for measuring it with but I was super careful.
Sent from my SM-G988B using Tapatalk
1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
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- DDK 1st, 2nd and 3rd for me!
- Posts: 2060
- Joined: Thu Jul 08, 2021 8:18 am
- Location: Lichfield
Re: Assessing an unknown engine
And 62.03mm across the engine bore although that was trickier to measure. Not sure what spec is. Maybe it says in Dempsey.
Sent from my SM-G988B using Tapatalk
Sent from my SM-G988B using Tapatalk
1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
-
- DDK 1st, 2nd and 3rd for me!
- Posts: 2060
- Joined: Thu Jul 08, 2021 8:18 am
- Location: Lichfield
Re: Assessing an unknown engine
After making up a cam nut removal tool today I found a bit of time to revisit this broken flywheel stud. After covering up all the journals and threads to protect from spatter, I welded the sheared head back on and it reversed straight out with the mini impact driver.
I used another stud as the earth to avoid causing any pitting to any of the crank surfaces.
Sent from my SM-G988B using Tapatalk
I used another stud as the earth to avoid causing any pitting to any of the crank surfaces.
Sent from my SM-G988B using Tapatalk
1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
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- Nurse, I think I need some assistance
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Re: Assessing an unknown engine
Good recovery. I guess the heat from the welding was your friend here
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- DDK 1st, 2nd and 3rd for me!
- Posts: 2060
- Joined: Thu Jul 08, 2021 8:18 am
- Location: Lichfield
Re: Assessing an unknown engine
No progress this past couple of weeks, as the good weather has had me doing other things.
But to catch up on some more of the dismantling... the cams are in great health, which is bitter sweet in a way because they'll be off to Newman cams for a mod solex grind, which is the direction I think I'm going with this engine.
This stud refused to come out, stripping the inner hex because there wasn't enough of it above the stud to take the torque.
Three nuts were sitting too deep. Maybe they were meant to be installed with a thicker washer? The washers were very thin.
I finally got the last one by cutting the centre out of an allen key so it would sit deeper in the nut.
The stash of parts is building up on my new shelf.
Used nearly a hundred ziplock bags so far.
The rocker arms and shafts seem in good health and a snug fit, but Newman say they will need machining to make sure they're spot on, to prevent uneven wear on the new cam.
It didn't show in the photo, but cylinder numbers are scratched into the top corners of the heads, confirming once again the engine's been apart before.
Can't remember if I posted this before but the IMS gear is all good.
And I've ordered some micrometers to take various measurements on the crank and case. I need to do some research, and possibly engage my ingenuity to think about how to measure whether it needs a line bore.
Also, advice is to pull the studs from the case and put case savers in. They seem so solid and in so well, it seems unnecessary and runs the risk of creating a problem out of nothing. But I think I have to defer to the experience of the experts.
Sent from my SM-S918B using Tapatalk
But to catch up on some more of the dismantling... the cams are in great health, which is bitter sweet in a way because they'll be off to Newman cams for a mod solex grind, which is the direction I think I'm going with this engine.
This stud refused to come out, stripping the inner hex because there wasn't enough of it above the stud to take the torque.
Three nuts were sitting too deep. Maybe they were meant to be installed with a thicker washer? The washers were very thin.
I finally got the last one by cutting the centre out of an allen key so it would sit deeper in the nut.
The stash of parts is building up on my new shelf.
Used nearly a hundred ziplock bags so far.
The rocker arms and shafts seem in good health and a snug fit, but Newman say they will need machining to make sure they're spot on, to prevent uneven wear on the new cam.
It didn't show in the photo, but cylinder numbers are scratched into the top corners of the heads, confirming once again the engine's been apart before.
Can't remember if I posted this before but the IMS gear is all good.
And I've ordered some micrometers to take various measurements on the crank and case. I need to do some research, and possibly engage my ingenuity to think about how to measure whether it needs a line bore.
Also, advice is to pull the studs from the case and put case savers in. They seem so solid and in so well, it seems unnecessary and runs the risk of creating a problem out of nothing. But I think I have to defer to the experience of the experts.
Sent from my SM-S918B using Tapatalk
1970 911T, Signal orange (Restoration thread)
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.
1988 3.2 Carrera backdate, Black
2001 996 Turbo, Lapis blue (am I allowed to put that here?)
I'm looking for a pre-impact bumper 911S or other high-revving 911 to restore - please let me know if you see one.