Rebuild nightmare
08-30-11, 10:50 PM
#1
Rebuild nightmare
I'm going to briefly summarize the issues I've had with an engine I recently rebuild.
The car is a 87 GTU with approx 250 miles. The previous owner was a drifter so the car has upgraded suspension and was " modified" and over heated " a few times" prior to the current owner purchasing it. To be frank the engine was clearly mistreated for an unspecified amount of time. Anyway, a few weeks ago I get a call late night from a fellow club member who tells me he thinks his engine might have popped... Ok no big deal "bring it by and I'll take a look at it". So, I check out the car and sure enough it's popped. I quote the rebuild price and we progress from there. I pull the engine smoothly enough no major issues to report as pulling an engine is pretty standard. His wiring harness has a craptastic emissions removal, but i tend to be overly picky about things like that.
Moving into the diasssembly I immediately notice that his clutch, flywheel and pressure plate are completely screwed up ( seriously irregular wear patterns and the like). OK pulling the engine apart I remove the rear plate and Immediately see a massive gouge in the plate. The rear rotor completely destroyed on the apex seal grove, and two of the faces. Rotor housing... destroyed, intermediate plate Destroyed. Front plate Micro fractured ( more on this later). So at this point he has one rotor housing and one rotor; plus the e-shaft and counterweights. No big deal I've got parts. So the rebuild commences.
Now I've reassembled at least 100 engines over the years, but I have never and I mean NEVER had anything close to the difficulty I had putting this engine together. New seals upgraded FD corner springs ect, ect. Stage 2 Street port all clearances and wear specs check out ( again used parts at the customer request( budget build) ) So, the entire time I'm assembling the engine something keeps not letting the plates settle onto the housings. Rotors are flush dowel pins are good, e-shaft spins freely. So Finally after a few hours of messing with it off and on everything is finally in place spinning freely and compression is excellent . Ok time to check for leaks while it's outside the car. This is just something I do to check to make sure there are no coolant issues. so I fill the block with coolant and pressurize everything to 15psi let it sit for 2 days. Sill holding pressure, still at 15PSI. Ok its good to go back in the car. So I pop on the oil pan bolt on the accessories and in the car she goes. Another happy customer ; or so I though.
well it's day 5 now and the engine is in the car.everything is wired up and topped off and ready for a restart. I turn the key and ..... nothing. WTF!!!So I start trouble shooting. Everything is still good. I've got compression, spark fuel, all the wires are in the right place Why isnt this working??? So along comes a club member who suggests it could be the starter and why not push start it.... Ok I've got nothing to lose. So we use the shop truck and gently nudge the car. Viola' !!! it's alive!!! cool it's running now. Then after a minute it's dead again. Screw this I'm going home to my GF I'll deal with this in the morning. The next day it starts again, the dies for pretty much half the day. At this point I'm really annoyed. So I check for vacuum leaks. No leaks. Fuel injectors are swapped out nope those are good. ECU, MAF ect all good. Finally we get the car to run for a few minutes at which point it's pouring out white smoke !?!?!?! WTF now!!!. I track the smoke down to a massive crack that has now appeared in the front plate. Evidently the plate was cracked on the inner water jacket where I couldn't see it , and it decided to take this moment to fail on me. Well, Great i get to pull it again. So I remove the engine again and rebuild it Again, and go through my quality control again. reinstall the engine, and proceed to test fire it again. This time there is some stumbling as the starter kicks over but still not love from the FC. I am now officially pissed as I've used the absolute best quality used parts Ive got on hand and have rebuilt this engine twice and now wasted several days working on it. So we push it again. This time it runs and runs and then it dies. But no smoke or mixing of oil and coolant. OK, WTF is really going on here??? So today I pull the manifolds again but this time the lower manifold literally falls apart in my hand. It's been cracked this whole time. Now this manifold was suspect from the beginning since it was an S4 lower with a modified S5 upper, but it worked before with no problems so I let it slide. If it ain't broke don't fix it right ??? Anyway, tonight I installed an S4 upper on a new S4 lower bolted everything up and tomorrow we will see if this nightmare will continue any longer. Because at this point the only things left from the original engine are the one rotor one housing and the E-shaft, and my patience is gone.
The car is a 87 GTU with approx 250 miles. The previous owner was a drifter so the car has upgraded suspension and was " modified" and over heated " a few times" prior to the current owner purchasing it. To be frank the engine was clearly mistreated for an unspecified amount of time. Anyway, a few weeks ago I get a call late night from a fellow club member who tells me he thinks his engine might have popped... Ok no big deal "bring it by and I'll take a look at it". So, I check out the car and sure enough it's popped. I quote the rebuild price and we progress from there. I pull the engine smoothly enough no major issues to report as pulling an engine is pretty standard. His wiring harness has a craptastic emissions removal, but i tend to be overly picky about things like that.
Moving into the diasssembly I immediately notice that his clutch, flywheel and pressure plate are completely screwed up ( seriously irregular wear patterns and the like). OK pulling the engine apart I remove the rear plate and Immediately see a massive gouge in the plate. The rear rotor completely destroyed on the apex seal grove, and two of the faces. Rotor housing... destroyed, intermediate plate Destroyed. Front plate Micro fractured ( more on this later). So at this point he has one rotor housing and one rotor; plus the e-shaft and counterweights. No big deal I've got parts. So the rebuild commences.
Now I've reassembled at least 100 engines over the years, but I have never and I mean NEVER had anything close to the difficulty I had putting this engine together. New seals upgraded FD corner springs ect, ect. Stage 2 Street port all clearances and wear specs check out ( again used parts at the customer request( budget build) ) So, the entire time I'm assembling the engine something keeps not letting the plates settle onto the housings. Rotors are flush dowel pins are good, e-shaft spins freely. So Finally after a few hours of messing with it off and on everything is finally in place spinning freely and compression is excellent . Ok time to check for leaks while it's outside the car. This is just something I do to check to make sure there are no coolant issues. so I fill the block with coolant and pressurize everything to 15psi let it sit for 2 days. Sill holding pressure, still at 15PSI. Ok its good to go back in the car. So I pop on the oil pan bolt on the accessories and in the car she goes. Another happy customer ; or so I though.
well it's day 5 now and the engine is in the car.everything is wired up and topped off and ready for a restart. I turn the key and ..... nothing. WTF!!!So I start trouble shooting. Everything is still good. I've got compression, spark fuel, all the wires are in the right place Why isnt this working??? So along comes a club member who suggests it could be the starter and why not push start it.... Ok I've got nothing to lose. So we use the shop truck and gently nudge the car. Viola' !!! it's alive!!! cool it's running now. Then after a minute it's dead again. Screw this I'm going home to my GF I'll deal with this in the morning. The next day it starts again, the dies for pretty much half the day. At this point I'm really annoyed. So I check for vacuum leaks. No leaks. Fuel injectors are swapped out nope those are good. ECU, MAF ect all good. Finally we get the car to run for a few minutes at which point it's pouring out white smoke !?!?!?! WTF now!!!. I track the smoke down to a massive crack that has now appeared in the front plate. Evidently the plate was cracked on the inner water jacket where I couldn't see it , and it decided to take this moment to fail on me. Well, Great i get to pull it again. So I remove the engine again and rebuild it Again, and go through my quality control again. reinstall the engine, and proceed to test fire it again. This time there is some stumbling as the starter kicks over but still not love from the FC. I am now officially pissed as I've used the absolute best quality used parts Ive got on hand and have rebuilt this engine twice and now wasted several days working on it. So we push it again. This time it runs and runs and then it dies. But no smoke or mixing of oil and coolant. OK, WTF is really going on here??? So today I pull the manifolds again but this time the lower manifold literally falls apart in my hand. It's been cracked this whole time. Now this manifold was suspect from the beginning since it was an S4 lower with a modified S5 upper, but it worked before with no problems so I let it slide. If it ain't broke don't fix it right ??? Anyway, tonight I installed an S4 upper on a new S4 lower bolted everything up and tomorrow we will see if this nightmare will continue any longer. Because at this point the only things left from the original engine are the one rotor one housing and the E-shaft, and my patience is gone.
08-30-11, 11:05 PM
#3
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Ouch man... Hopefully this one is the one that works for ya! And speaking of S5 upper on S4 lower, is it bad to do so (obviously needs minor work to fit correctly), or is it fine as long as nothing is half assed?
08-30-11, 11:17 PM
#4
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this is exactly why i don't build engines for people!
08-30-11, 11:25 PM
#5
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Wow talk about an engine build nightmare! Just mark this one up to the worse luck imaginable!
After about 100 or so engines you are bound to find one that should have a Stamp on it in big bold letters saying FUBAR enjoy!
After about 100 or so engines you are bound to find one that should have a Stamp on it in big bold letters saying FUBAR enjoy!
08-31-11, 12:00 AM
#6
Paragraphs are your friend.
But seriously , that is some rotten luck! You just can't trust drifters, I've been helping a buddy of mine repair the hack job mods the drifter p.o. preformed. Fortunately the engine is about the only thing he didn't screw up.
But seriously , that is some rotten luck! You just can't trust drifters, I've been helping a buddy of mine repair the hack job mods the drifter p.o. preformed. Fortunately the engine is about the only thing he didn't screw up.
08-31-11, 07:37 AM
#8
+1
I've rebuilt close to 20 engines and haven't had to pull any back apart for those two issues. It must be a special honor you only receive when you reach the 100 mark. GRATZ!
I'm about to change cars. I might go MKIII supra. I always wanted to rebuild an I6. At least they don't have any problems like this...RIGHT???
I've rebuilt close to 20 engines and haven't had to pull any back apart for those two issues. It must be a special honor you only receive when you reach the 100 mark. GRATZ!
I'm about to change cars. I might go MKIII supra. I always wanted to rebuild an I6. At least they don't have any problems like this...RIGHT???
08-31-11, 10:00 AM
#11
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08-31-11, 01:01 PM
#13
S5 upper to S4 lower? geez. I mean I know you can make it work but that's one more thing to go wrong.
rod knock and blown head gasket are the most common problems with the 7M engines. There are ways to address those issues but right out of the box stuff will eventually go wrong.
rod knock and blown head gasket are the most common problems with the 7M engines. There are ways to address those issues but right out of the box stuff will eventually go wrong.
08-31-11, 01:06 PM
#14
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lol, i just had to look, i thought the mk3 was the newer one.... but yeah the 7m is famous for blowing head gaskets, stock.
09-01-11, 08:35 AM
#15
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Well the update on this would be.....now with a new mani the car now doesn't sputter,start or run...anything even if we push it..were going to try changing in a new harness to see if that addresses the issue. if it comes down to it im willing to separate from them so i can pick up a daily..http://charleston.craigslist.org/for/2576247173.html
Last edited by Sabora; 09-01-11 at 08:56 AM.
09-02-11, 04:46 PM
#19
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On the bright side, once you get the head machined and the new gasket in you are good and reliable for some power. But again on the dark side, I think they weigh the same as a caddy.
09-02-11, 05:00 PM
#20
welcome to my world, i deal with these sorts of stories almost everyday.
problem is almost none of these cars are original anymore and almost 100% of them have been reinstalled/reassembled incorrectly in one way or another.
it really feels good to me when i assemble a motor in stock configuration and can look at it and there is no discernable way to tell it was assembled any other way than it was when it rolled off the factory floor.
problem is almost none of these cars are original anymore and almost 100% of them have been reinstalled/reassembled incorrectly in one way or another.
it really feels good to me when i assemble a motor in stock configuration and can look at it and there is no discernable way to tell it was assembled any other way than it was when it rolled off the factory floor.
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