Assessing an unknown engine
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Re: Assessing an unknown engine
This sprocket came away easily and I heeded Dempsey's warning to keep hold of the pin and not drop it into the engine.
This sprocket came away easily
There was no such warning about dropping the Woodruff key, although that should have been obvious to me to put the little magnet on it. It was quite stuck but I pushed it with a screwdriver until it suddenly yielded and gave way to the tinkling sound of metal landing in the engine case below. It was, of course, nowhere to be seen but thankfully a blind fishing exercise with the magnet came up successful.
Next came the shims - make a note which ones came from this side of the engine.
And this fat washer had a chamfered edge which face in towards the engine.
I was left thinking it was a lot easier for Dempsey to write "pry out the cam end cover with a screwdriver" in the book than it was to actually accomplish this feat in the real world.
I ended up taking the different route of removing the chain cover with the cylinder heads, before I realised you can actually access this cam end cover from the back to push it out.
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This sprocket came away easily
There was no such warning about dropping the Woodruff key, although that should have been obvious to me to put the little magnet on it. It was quite stuck but I pushed it with a screwdriver until it suddenly yielded and gave way to the tinkling sound of metal landing in the engine case below. It was, of course, nowhere to be seen but thankfully a blind fishing exercise with the magnet came up successful.
Next came the shims - make a note which ones came from this side of the engine.
And this fat washer had a chamfered edge which face in towards the engine.
I was left thinking it was a lot easier for Dempsey to write "pry out the cam end cover with a screwdriver" in the book than it was to actually accomplish this feat in the real world.
I ended up taking the different route of removing the chain cover with the cylinder heads, before I realised you can actually access this cam end cover from the back to push it out.
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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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Re: Assessing an unknown engine
Dempsey says these chain guides are a single use item, but these appear to be brand new.
Judging by the nuts and some sealant around the rocker covers, I'm sure somebody's been in this engine during its 10 years of use. I'm guessing they had recently replaced these before the vehicle in which this engine was situated met its demist.
Following Dempsey, for a moment I thought I must have missed some steps, when I realised I was removing the cylinder studs not having removed the cylinder heads and rocker covers yet. But rechecking the book confirmed that's the way you do it.
That all came away nicely, and the faces of the valves which would not have been coated in oil, looked a bit corroded.
Getting a bit closer to the business end of things, what I thought on the bore scope looked like corroded pistons, appears to simply be carbon build up.
In fact a little later, a scrape with my fingernail and gentle rub off with tissue would reveal nice steel underneath.
I don't know if this is a shim or a gasket - is it original factory, or does it signify somebody's been carried out some work?
The barrels book a bit of freeing up with the old plastic mallet but a good pull and a wobble and the first couple came away. I wpied them with a tissue and I thought they looked good.
At this point, and this is very much a tentative view, I'm starting to think my fears about the state of the engine were unfounded and it seems to be in rude health - barely used, in fact.
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Judging by the nuts and some sealant around the rocker covers, I'm sure somebody's been in this engine during its 10 years of use. I'm guessing they had recently replaced these before the vehicle in which this engine was situated met its demist.
Following Dempsey, for a moment I thought I must have missed some steps, when I realised I was removing the cylinder studs not having removed the cylinder heads and rocker covers yet. But rechecking the book confirmed that's the way you do it.
That all came away nicely, and the faces of the valves which would not have been coated in oil, looked a bit corroded.
Getting a bit closer to the business end of things, what I thought on the bore scope looked like corroded pistons, appears to simply be carbon build up.
In fact a little later, a scrape with my fingernail and gentle rub off with tissue would reveal nice steel underneath.
I don't know if this is a shim or a gasket - is it original factory, or does it signify somebody's been carried out some work?
The barrels book a bit of freeing up with the old plastic mallet but a good pull and a wobble and the first couple came away. I wpied them with a tissue and I thought they looked good.
At this point, and this is very much a tentative view, I'm starting to think my fears about the state of the engine were unfounded and it seems to be in rude health - barely used, in fact.
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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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Re: Assessing an unknown engine
The pistons look good to me, a bit of varnish or something on this one.
And there's definitely some marking of some sort on this barrel.
I guess I should get an expert to advise me whether these need reboring or honing.
A friend of mine said he simply ran a stood engine for a while, which was spewing out blue smoke, and after a few miles it was like new again. The rings just needed to seat. I don't think I'll chance that approach on this engine.
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And there's definitely some marking of some sort on this barrel.
I guess I should get an expert to advise me whether these need reboring or honing.
A friend of mine said he simply ran a stood engine for a while, which was spewing out blue smoke, and after a few miles it was like new again. The rings just needed to seat. I don't think I'll chance that approach on this engine.
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!
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Re: Assessing an unknown engine
My curiosity has probably kept me going longer than I ought without having a tidy up. Everything is already going organised into freezer bags, but I'll probably go and sort some bench space for all the bits before going any further.
I'm also starting to regret not cleaning the outside of the engine better first, as the imperative to split the case is declining now, so the concern I may have introduced debris into it becomes more of a consideration. I'm almost thinking it might be better to not slide the other barrels off their piston rings.
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I'm also starting to regret not cleaning the outside of the engine better first, as the imperative to split the case is declining now, so the concern I may have introduced debris into it becomes more of a consideration. I'm almost thinking it might be better to not slide the other barrels off their piston rings.
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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Re: Assessing an unknown engine
You are right!
A good external clean would have helped, but now you are here, just tear the lot apart down to the crank. You need to check a lot more yet Rob, the intermediate shaft clearance and float and other things. The pistons will clean well, i think that bore will hone, but you need an engine shop to advise.
Valves should clean, but the seats?
The thin copper rings at the bottom of each barrel is right, but you need new to re-assemble, they are designed to cruch and seal from oil leaks.
Take a look at the repair 'kit' that Design911 sell for doing the top and the bottom of these engines, you get all you need bar the pistons and barrels.
Best to replace all bearing surfaces, shells to ramps to chains etc.
I've used their kits for my 3.2 and it was great.
Cleanliness is godlyness, clean once, twice and trice and then again.
I would be cleaning parts roughly as I bag them or you will be a right old mess, but that's just me maybe!
A good external clean would have helped, but now you are here, just tear the lot apart down to the crank. You need to check a lot more yet Rob, the intermediate shaft clearance and float and other things. The pistons will clean well, i think that bore will hone, but you need an engine shop to advise.
Valves should clean, but the seats?
The thin copper rings at the bottom of each barrel is right, but you need new to re-assemble, they are designed to cruch and seal from oil leaks.
Take a look at the repair 'kit' that Design911 sell for doing the top and the bottom of these engines, you get all you need bar the pistons and barrels.
Best to replace all bearing surfaces, shells to ramps to chains etc.
I've used their kits for my 3.2 and it was great.
Cleanliness is godlyness, clean once, twice and trice and then again.
I would be cleaning parts roughly as I bag them or you will be a right old mess, but that's just me maybe!
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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Re: Assessing an unknown engine
I note the top two rings here spring out.
While the top two here seem stuck in their groove.
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While the top two here seem stuck in their groove.
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!
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Re: Assessing an unknown engine
This one will not budge. Any suggestions are welcome, especially those known to work and not damage the engine.
For now, I'm leaving it with some penetrating oil to sink in.
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For now, I'm leaving it with some penetrating oil to sink in.
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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Re: Assessing an unknown engine
Diesel has been known to loosen things off?
That and (maybe not at the same time!) heat around the edge of the piston whilst gently tapping it with the handle of a heavy hammer.
That and (maybe not at the same time!) heat around the edge of the piston whilst gently tapping it with the handle of a heavy hammer.
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Re: Assessing an unknown engine
That is correct Gary, also using auto box trans fluid, all good at seeping into closed gaps.
Bit of hot air gun always helps...
Rob, this afternoon roughly costed up the parts to rebuild my elderly 3.2 in my 73T.
About £2000 should cover it.
All costs from Design911 but there is a good discounts available at that spend, and 10% for PCGB members.
That should pay for putting the Lola in storage so to have the space to do the engine.
Bit of hot air gun always helps...
Rob, this afternoon roughly costed up the parts to rebuild my elderly 3.2 in my 73T.
About £2000 should cover it.
All costs from Design911 but there is a good discounts available at that spend, and 10% for PCGB members.
That should pay for putting the Lola in storage so to have the space to do the engine.
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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Re: Assessing an unknown engine
"Never again" I'm pretty sure you said last time.911hillclimber wrote:Rob, this afternoon roughly costed up the parts to rebuild my elderly 3.2 in my 73T.
About £2000 should cover it.
Anyway, I think you should twin plug that one too.
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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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- Nurse, I think I need some assistance
- Posts: 18970
- Joined: Mon Mar 10, 2008 6:26 pm
- Location: West Midlands
Re: Assessing an unknown engine
I think I meant Never Again will I do a modiofied 911 engine, but a stock rebuild will be easy by comparison.
A nice reliable Clewett system would be good over the 1986 Bosche DME?
Don't think that will happen again in my garage!
You will need a lot of paraffin to rough wash those parts, the longer the soak the better, esp the heads.
Laid out, a 911 engine ready to build takes up a HUGE amount of bench space.
A nice reliable Clewett system would be good over the 1986 Bosche DME?
Don't think that will happen again in my garage!
You will need a lot of paraffin to rough wash those parts, the longer the soak the better, esp the heads.
Laid out, a 911 engine ready to build takes up a HUGE amount of bench space.
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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- DDK 1st, 2nd and 3rd for me!
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Re: Assessing an unknown engine
After making room for some of the parts, I turned the engine over today and removed the other rocker assembly. The left side of the engine tells a different story. These must have been the problems seen on the scope. Two pistons are broken where the exhaust valve cutout meets the barrel.
With both chains free I was able to put the belt pulley back non and give thr flywheel a gentle turn. It's clearly locked somewhere, but it wobbles enough to show the pistons on this side are moving freely in their cylinders, despite the broken piatons some discolouration possibly indicative of heat.
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With both chains free I was able to put the belt pulley back non and give thr flywheel a gentle turn. It's clearly locked somewhere, but it wobbles enough to show the pistons on this side are moving freely in their cylinders, despite the broken piatons some discolouration possibly indicative of heat.
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
There’s no (visible) scoring on the bores from that damage?
Difficult to see from the photos, but is the top of the piston clean or is it some deposit build ups that then look like damage?
Difficult to see from the photos, but is the top of the piston clean or is it some deposit build ups that then look like damage?
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Re: Assessing an unknown engine
So that just leaves one cylinder on the engine, on the other side. Gently turning the crankshaft I was able to confirm it's this cylinder restricting the movement of the crank. I guess I'll add some more fluid and save that battle for another day.
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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!
- Posts: 2068
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Re: Assessing an unknown engine
There's something there but I'd say it's more subtle corrosion. I think there is the slightest hint of a score although I only saw it once I took these photos. (All the same barrel).Gary71 wrote:There’s no (visible) scoring on the bores from that damage?
Difficult to see from the photos, but is the top of the piston clean or is it some deposit build ups that then look like damage?
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.