1986 928s Excessive oil in intake / burning oil
04-25-2016, 11:43 PM
#77
Rennlist Member
If I had to guess, it was a leaky injector on 7 and it hydrolocked and broke the ring. You could rotate it backwards because you were no longer trying to compress a cylinder full of gasoline, and eventually it drained through the broken rings into the crankcase, or you rotated it backwards until it opened a valve and it evaporated.
04-26-2016, 01:00 AM
#78
Rennlist Member
Save the pain.
Running 944's cost less than the cheapest carbureted backwoods conversion.
Last one we bought was Saturday.
$650 running, sitting on an $800 set of fuchs.
Running 944's cost less than the cheapest carbureted backwoods conversion.
Last one we bought was Saturday.
$650 running, sitting on an $800 set of fuchs.
04-26-2016, 01:25 AM
#79
Rennlist Member
The hard part is understanding why cranking long would cause the engine to seize. The oil pump is still pumping oil, the water pump is turning, there's no forces from combustion, and it's spinning at a leisurely 300 or so RPM.
Starter motor burning out, that makes sense. But how does slowly turning the engine over for a long time cause it to seize?
Starter motor burning out, that makes sense. But how does slowly turning the engine over for a long time cause it to seize?
04-26-2016, 02:47 AM
#80
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If I had to guess, it was a leaky injector on 7 and it hydrolocked and broke the ring. You could rotate it backwards because you were no longer trying to compress a cylinder full of gasoline, and eventually it drained through the broken rings into the crankcase, or you rotated it backwards until it opened a valve and it evaporated.
04-26-2016, 04:33 AM
#82
Rennlist Member
Another day another dollar in my part of the world!
Two cups of coffee and having just unblocked our drain pipe into the septic tank I need something to brighten my day!
Saddened to learn of your compression pressure but not in the least bit surprised. Let's discuss your situation & options a little further:
1. At the moment you own a garden ornament that has a 5 speed manual transmission and possibly [but not necessarily] a fubar'd eng.
2. Depending on chassis condition what you have probably has some value to a few on this list.
3. We do not know why your motor goosed itself, neither do you and clearly you do not know the extent of the mechanical damage any more than we do. Your piston[s] could be knackered, you might have a [slightly] bent rod, you could have a bent valve and possibly the job lot.
4. If you have the time and inclination the smart thing to do would be to pull the heads to permit deeper evaluation. If the damage is limited to the heads an in-situ fix is possible [I think?]. That you previously saw something in the engine oil suggests chunks of metal missing from somewhere so more likely we can expect the worst at this stage and just hope for something a bit better.
5. Your first option is to walk away from the train wreck and offer it as a job lot- street value depending on the condition of the residue.
6. Second option is to assume the motor is naffed and enquire about a replacement- not currently on your radar but who knows - you might change your mind.
7. Keep your options further open and investigate whether a repair is possible.
8. You walk away from a 928 motor and fit a Genetically Modified Vee8. I have no idea how much it will cost to shoehorn one of these things into a 928 chassis and make it work but I rather suspect it will take an awful lot of someone's effort. Why is it difficult to do- just look at the size of the GM lump- the 928 vee 8 is a work of art packaging wise not so sure the same can be said about the GM lump. We know it can be done but you would need to speak to someone who has tried it. As I said earlier- not in the least bit interesting to most on this list but whatever.
Sounds to me your best bet at this moment in time is to offer the garden ornament to the folks on this list who might be charitable and offer you a grand or two. You are staring at a minimum bill of $5k I suspect assuming you can do the work [whatever it is that is needed].
If you were to get a motor from someone on this list chances of success improve somewhat but still no guarantee -Speedtoys has[?] a 32V motor for sale- no idea if it would suit your application but he is very knowledgeable about 928's].
928's can be cheap to buy but there is an inversely proportional linkage between cost to purchase and cost to operate and it is not linear.
You now have to make some decisions as to your way forwards.
Wishing you well
Two cups of coffee and having just unblocked our drain pipe into the septic tank I need something to brighten my day!
Saddened to learn of your compression pressure but not in the least bit surprised. Let's discuss your situation & options a little further:
1. At the moment you own a garden ornament that has a 5 speed manual transmission and possibly [but not necessarily] a fubar'd eng.
2. Depending on chassis condition what you have probably has some value to a few on this list.
3. We do not know why your motor goosed itself, neither do you and clearly you do not know the extent of the mechanical damage any more than we do. Your piston[s] could be knackered, you might have a [slightly] bent rod, you could have a bent valve and possibly the job lot.
4. If you have the time and inclination the smart thing to do would be to pull the heads to permit deeper evaluation. If the damage is limited to the heads an in-situ fix is possible [I think?]. That you previously saw something in the engine oil suggests chunks of metal missing from somewhere so more likely we can expect the worst at this stage and just hope for something a bit better.
5. Your first option is to walk away from the train wreck and offer it as a job lot- street value depending on the condition of the residue.
6. Second option is to assume the motor is naffed and enquire about a replacement- not currently on your radar but who knows - you might change your mind.
7. Keep your options further open and investigate whether a repair is possible.
8. You walk away from a 928 motor and fit a Genetically Modified Vee8. I have no idea how much it will cost to shoehorn one of these things into a 928 chassis and make it work but I rather suspect it will take an awful lot of someone's effort. Why is it difficult to do- just look at the size of the GM lump- the 928 vee 8 is a work of art packaging wise not so sure the same can be said about the GM lump. We know it can be done but you would need to speak to someone who has tried it. As I said earlier- not in the least bit interesting to most on this list but whatever.
Sounds to me your best bet at this moment in time is to offer the garden ornament to the folks on this list who might be charitable and offer you a grand or two. You are staring at a minimum bill of $5k I suspect assuming you can do the work [whatever it is that is needed].
If you were to get a motor from someone on this list chances of success improve somewhat but still no guarantee -Speedtoys has[?] a 32V motor for sale- no idea if it would suit your application but he is very knowledgeable about 928's].
928's can be cheap to buy but there is an inversely proportional linkage between cost to purchase and cost to operate and it is not linear.
You now have to make some decisions as to your way forwards.
Wishing you well
04-26-2016, 06:57 AM
#83
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04-26-2016, 07:12 AM
#84
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Another day another dollar in my part of the world!
Two cups of coffee and having just unblocked our drain pipe into the septic tank I need something to brighten my day!
Saddened to learn of your compression pressure but not in the least bit surprised. Let's discuss your situation & options a little further:
1. At the moment you own a garden ornament that has a 5 speed manual transmission and possibly [but not necessarily] a fubar'd eng.
2. Depending on chassis condition what you have probably has some value to a few on this list.
3. We do not know why your motor goosed itself, neither do you and clearly you do not know the extent of the mechanical damage any more than we do. Your piston[s] could be knackered, you might have a [slightly] bent rod, you could have a bent valve and possibly the job lot.
4. If you have the time and inclination the smart thing to do would be to pull the heads to permit deeper evaluation. If the damage is limited to the heads an in-situ fix is possible [I think?]. That you previously saw something in the engine oil suggests chunks of metal missing from somewhere so more likely we can expect the worst at this stage and just hope for something a bit better.
5. Your first option is to walk away from the train wreck and offer it as a job lot- street value depending on the condition of the residue.
6. Second option is to assume the motor is naffed and enquire about a replacement- not currently on your radar but who knows - you might change your mind.
7. Keep your options further open and investigate whether a repair is possible.
8. You walk away from a 928 motor and fit a Genetically Modified Vee8. I have no idea how much it will cost to shoehorn one of these things into a 928 chassis and make it work but I rather suspect it will take an awful lot of someone's effort. Why is it difficult to do- just look at the size of the GM lump- the 928 vee 8 is a work of art packaging wise not so sure the same can be said about the GM lump. We know it can be done but you would need to speak to someone who has tried it. As I said earlier- not in the least bit interesting to most on this list but whatever.
Sounds to me your best bet at this moment in time is to offer the garden ornament to the folks on this list who might be charitable and offer you a grand or two. You are staring at a minimum bill of $5k I suspect assuming you can do the work [whatever it is that is needed].
If you were to get a motor from someone on this list chances of success improve somewhat but still no guarantee -Speedtoys has[?] a 32V motor for sale- no idea if it would suit your application but he is very knowledgeable about 928's].
928's can be cheap to buy but there is an inversely proportional linkage between cost to purchase and cost to operate and it is not linear.
You now have to make some decisions as to your way forwards.
Wishing you well
Two cups of coffee and having just unblocked our drain pipe into the septic tank I need something to brighten my day!
Saddened to learn of your compression pressure but not in the least bit surprised. Let's discuss your situation & options a little further:
1. At the moment you own a garden ornament that has a 5 speed manual transmission and possibly [but not necessarily] a fubar'd eng.
2. Depending on chassis condition what you have probably has some value to a few on this list.
3. We do not know why your motor goosed itself, neither do you and clearly you do not know the extent of the mechanical damage any more than we do. Your piston[s] could be knackered, you might have a [slightly] bent rod, you could have a bent valve and possibly the job lot.
4. If you have the time and inclination the smart thing to do would be to pull the heads to permit deeper evaluation. If the damage is limited to the heads an in-situ fix is possible [I think?]. That you previously saw something in the engine oil suggests chunks of metal missing from somewhere so more likely we can expect the worst at this stage and just hope for something a bit better.
5. Your first option is to walk away from the train wreck and offer it as a job lot- street value depending on the condition of the residue.
6. Second option is to assume the motor is naffed and enquire about a replacement- not currently on your radar but who knows - you might change your mind.
7. Keep your options further open and investigate whether a repair is possible.
8. You walk away from a 928 motor and fit a Genetically Modified Vee8. I have no idea how much it will cost to shoehorn one of these things into a 928 chassis and make it work but I rather suspect it will take an awful lot of someone's effort. Why is it difficult to do- just look at the size of the GM lump- the 928 vee 8 is a work of art packaging wise not so sure the same can be said about the GM lump. We know it can be done but you would need to speak to someone who has tried it. As I said earlier- not in the least bit interesting to most on this list but whatever.
Sounds to me your best bet at this moment in time is to offer the garden ornament to the folks on this list who might be charitable and offer you a grand or two. You are staring at a minimum bill of $5k I suspect assuming you can do the work [whatever it is that is needed].
If you were to get a motor from someone on this list chances of success improve somewhat but still no guarantee -Speedtoys has[?] a 32V motor for sale- no idea if it would suit your application but he is very knowledgeable about 928's].
928's can be cheap to buy but there is an inversely proportional linkage between cost to purchase and cost to operate and it is not linear.
You now have to make some decisions as to your way forwards.
Wishing you well
Its not getting sold. Its going to sit until in decide what to do with my own car. You've personally been more helpful than any of the chuckles here in the thread, and I thank you for that.
Otherwise, those who can't be bothered to read the thread before telling me what I did can get lost. The car didn't start in cold conditions, got cranked with the starter for ~2 minutes solid because I got pissed off, and seized a single piston. There wasn't any debris, like the man who cannot be bothered to read suggests; it seized. Simple and plain.
Its sitting with a cylinder full of ATF fluid on the off chance the rings are stuck with gummed up trash or corrosion and I'll try testing it again later this week and hope I am due for a small miracle.
Elsewise, I'd honestly run the engine with the plug wire and injector for that cylinder disconnected before I'd sell it to someone i don't know for a major loss over what I paid for it.
It'd be nice to do the rings on that cylinder but I don't have a garage, I don't have the tools, and I don't know if I'm keeping that engine. These engines are trash for the expense and complete lack of tuning options besides a chip or thousands of dollars to fit a supercharger - to say otherwise is just the purist in you talking and is delusion.
Anyway there isn't any damage to the piston other than the rings, there isn't any damage to the rod for Christ's sake, and the simple fact is that cylinder overheated after an extended idiot session cranking the engine when i was pissed off and it seized up solid. End of story.
Its really pissing me off how many folks have declined to read the thread and tried to chime in and tell me I am wrong about what I did when I sat there in the driveway with the key held for ~2 minutes before it seized up.
04-26-2016, 08:10 AM
#85
Rennlist Member
04-26-2016, 08:18 AM
#86
Captain Obvious
Super User
Super User
You are wrong my darling! The cylinders don't overheat just from cranking and they don't sieze from cranking too. Regardless how long you are cranking and engine that hasn't fired, it will not sieze up if the oil pump works. And it worked. What you are not hearing is that something physically stopped that piston from going over TDC. You did everything in your power to force it over and eventually succeeded by destroying that cylinder. But a borescope down that spam plug hole and you will see the marks of your handy work on the piston. The only person not listening here is you. Too busy yelling at the World to hear what others are telling you? Calm down, cause it sounds you have anger issues anyways, and think logically. Eliminate all the possibilities and what's left is the truth.
04-26-2016, 08:23 AM
#87
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You are wrong my darling! The cylinders don't overheat just from cranking and they don't sieze from cranking too. Regardless how long you are cranking and engine that hasn't fired, it will not sieze up if the oil pump works. And it worked. What you are not hearing is that something physically stopped that piston from going over TDC. You did everything in your power to force it over and eventually succeeded by destroying that cylinder. But a borescope down that spam plug hole and you will see the marks of your handy work on the piston. The only person not listening here is you. Too busy yelling at the World to hear what others are telling you? Calm down, cause it sounds you have anger issues anyways, and think logically. Eliminate all the possibilities and what's left is the truth.
I washed the cylinder walls with gasoline IN THE DEAD OF WINTER and cranked the engine for far, far, far, far ,far too long and it mechanically seized. But again no amount of reason will get through to a drive by poster who didn't even read the thread - but knows all about a car they have never seen.
Appreciate if the mods would close this thread at this time.
04-26-2016, 08:24 AM
#88
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I may have had an anger issue, but no one can say that I was not honest. I'll update those who were helpful when the car is driving again, which it will be, just depends on how.
Again, I'd appreciate it if the mods would go ahead and close this thread at this time.
Again, I'd appreciate it if the mods would go ahead and close this thread at this time.
