Cause of my GT3's engine failure found
#31
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I feel that way Ur20V. In about two months I will likely find out if my prostate cancer, unfortunately a high grade disease, is metastatic, and what chemo choices I will have. As a mostly retired physician, I am a realist about potentially lethal illnesses, and just want to get our GT3 back on the road. It is a thousand miles away, and when it is done, I will fly out and take the long, winding road back to SC. As for the $ spent, I tend not to think about "what if's" both for my hobbies and my own health. Besides, my other interest and hobby is making and shooting ammunition. I reload for 14 different calibers, and a few days ago was accepted into another gun club, this one has ranges out to 800 meters, so when I get a good scope on my new 257 Weatherby, I will see what kind of ammunition i can make for this rifle too. Started on some 30 30 Winchester ammo yesterday for my son's new '94 Win lever gun. Gave his wife a rare, tuned by Cylinder and Slide early '70's Colt Combat Commander in 9mm last week, just perfect for her smaller hands. I load light rounds for her, as she is still recoil sensitive.
And my wife's new furniture looks very nice in our home.
I am good to go, so as always, all the best to each of you.....
And my wife's new furniture looks very nice in our home.
I am good to go, so as always, all the best to each of you.....
You are my favorite member on this forum. Knowing how to let life roll off your back like water. An inspiration to all who are lucky enough to meet you.
#32
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From: Somewhere in a galaxy far, far away....
i had a feeling it had to do with the plugs or coils as they were just changed.
Looks like you got a bad plug... what are the odds?!
Good to see it is all better.
I just had all my plugs and coils replaced along with coolant pipes pinned and welded
Also opened up transmission for refresh, new clutch and LSD.
Expensive, but ready for another 40k miles of high performance driving.
Looks like you got a bad plug... what are the odds?!
Good to see it is all better.
I just had all my plugs and coils replaced along with coolant pipes pinned and welded
Also opened up transmission for refresh, new clutch and LSD.
Expensive, but ready for another 40k miles of high performance driving.
#33
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We did everything we could to find the electrode in the cylinder and exhaust to no extent. A borescope is a tool, but not 100% definitive, and not some magical high def picture that some believe. The picture below explains why would couldn't see the broken electrode. The piece had smashed and lodged itself sideways in the head. Once the plug blew apart, the damage was done. Hindsight, rather doing as much detective work externally that we could, and rather than trying to save the customer some money, we should have told him he had to open up the motor to find the piece. That is a hard one to sell, but in the future that will be how it goes around here. We'll just continue pulling parts off the engine block until we find the pieces.
You could lay the flattened electrode perfectly in that groove in the head.
The piston did not look nearly this bad, and there was a small contact area at the very bottom edge of the piston, we decided to put in a new piston and cylinder assembly on that #3 to be safe. Head was sent to the shop and they cleaned it up and declared it to be very lucky there wasn't much damage in the scheme of things. Not even a bent valve.
After reassembling the engine and starting to test drive it, we run the car up to speed then decal to help break the rings in on that cylinder. Over two days of running the car to make sure it was broken in good before doing a high load high rpm run. Cruising on the interstate today, the car felt like it lost fuel for a second, then was fine, then about a minute later did the same thing. That screamed fuel delivery issue to me and I wanted to replace the pump before attempting any high speed runs.
Before ordering a pump, I looked into the fuse panel and found what I believe is the cause of the entire issue. How long the car has been running like this is beyond me. Since fixing the issue, some more driving with no issues and what seemed like a much smoother engine (open exhaust that he is running is always rowdy, and hard to pinpoint how smooth the engine is), and some high load runs, it seems to be running great. We will continue to do some more testing to make sure this was indeed the issue.
I'll let you guys figure out the issue:
You could lay the flattened electrode perfectly in that groove in the head.
The piston did not look nearly this bad, and there was a small contact area at the very bottom edge of the piston, we decided to put in a new piston and cylinder assembly on that #3 to be safe. Head was sent to the shop and they cleaned it up and declared it to be very lucky there wasn't much damage in the scheme of things. Not even a bent valve.
After reassembling the engine and starting to test drive it, we run the car up to speed then decal to help break the rings in on that cylinder. Over two days of running the car to make sure it was broken in good before doing a high load high rpm run. Cruising on the interstate today, the car felt like it lost fuel for a second, then was fine, then about a minute later did the same thing. That screamed fuel delivery issue to me and I wanted to replace the pump before attempting any high speed runs.
Before ordering a pump, I looked into the fuse panel and found what I believe is the cause of the entire issue. How long the car has been running like this is beyond me. Since fixing the issue, some more driving with no issues and what seemed like a much smoother engine (open exhaust that he is running is always rowdy, and hard to pinpoint how smooth the engine is), and some high load runs, it seems to be running great. We will continue to do some more testing to make sure this was indeed the issue.
I'll let you guys figure out the issue:
#34
glad to hear the car is almost ready to head back home with NamVet.
can only guess that one of those fuses is not the right rating for where it's at and that was a factor in the fuel cutting.
can only guess that one of those fuses is not the right rating for where it's at and that was a factor in the fuel cutting.
#35
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Fuses in row d look off.
#36
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The fuel pump fuse is gone. You've motor has just been sucking fuel instead of pushing it in to the motor.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
#37
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The fuel pump fuse is gone. You've motor has just been sucking fuel instead of pushing it in to the motor.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
Cheers,
Mike
#38
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^^^ huh? 993 gt3? Dfi?
991 is dfi not 997
And there is no 993 gt3. Gt2 yes.
991 is dfi not 997
And there is no 993 gt3. Gt2 yes.
#39
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However, I truly appreciate the supportive response though, many thanks!
Cheers,
Mike
#40
The fuel pump fuse is gone. You've motor has just been sucking fuel instead of pushing it in to the motor.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
don't know how that's possible with injectors but back in the day, when I was 16 years old, I had an Isuzu with a non working fuel pump. It ran fine up until the point where you needed a blast of fuel. I drove it that way for years.
Correct. Fuel pump fuse should be F1 in row D and is missing.
How has the car even been running? Limp-home mode?
#41
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Left two are fuel pump slots, 25amp, (turbo and gt3 use two (this threw me off for a minute when looking at the diagrams, etc), where as the M96/m97 used only the left slot). 3rd slot is a DME control unit of some sort and should be 7.5amp. 4th slot should be empty as there is no 2nd connect for the fuse and also according to the diagram (which you can just make out in the picture, but partially obscured by the 7.5 amp fuse....upper contact not present). When i primed the oil pressure, i noticed the fuse was only in the 2nd slot, which i thought was odd, but car had been running so didn't think anything of it. Starting thinking about it later and took a closer look at the orientation and was like woah!
#42
Wow this thread has been exhilirating to read. I hope all the best to NAM VET in the future with your health and GT3!
This sounds like it was resolved with a glance at one of the most over looked areas. Good follow up, sub'd to hear the final results after test drive with load!
This sounds like it was resolved with a glance at one of the most over looked areas. Good follow up, sub'd to hear the final results after test drive with load!
#43
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...so someone removed the fuel pump fuses after an engine oil change, to crank and prime the engine with fresh oil and did not put one back?...
#44
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From: Rock Hill, SC, just south of Charlotte, NC
Half way home in Louisville. Car ran like it should although I won't load the motor until I am close to home. Windows down top open all the way from KC. Pressures and temps fine.
Now for some bourbon beer and some ribs. All the best.....
NV
Now for some bourbon beer and some ribs. All the best.....
NV
#45
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^ love your attitude. i have MUCH to learn from you.
hope the ribs are good!
hope the ribs are good!