94 GTS Comes Back Strong(er)
11-02-2016, 03:27 PM
#18
Under the Lift
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Head gasket deterioration from not driving the car and letting it sit for years and years with old, acidic coolant. I change the coolant every 2-3 years and even test the pH occasionally.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
11-02-2016, 03:30 PM
#19
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A good call to pull the motor and do the heads. It is quite easy to assume there is no need but I rather feel that low mileage examples ar emore vulnerable to head gasket deterioration because they sit there idle for too long lack of circulation of the coolant possibly leads to a localised deterioration of the gasket and in some cases the top of the cylinder towers.
Having someone like Greg do the work for you must be the icing on the cake as it were. When I took on my current 928 over 10 years ago to put my late S4 motor in it, it was tempting to simply put the motor in the car and hope for the best. Fortunately I was smarter than that, instigated a tentative compression check, No 7 was duff, so we gutted the top end of the motor and dropped the sump but left the bottom end intact just like Greg did here. 10+ years on no real issues to date but the sump gasket is weeping a bit now.
To the OP hopefully you will have many happy years of motoring knowing that a very safe pair of hands has checked it over and sorted it out.
Rgds
Fred
Having someone like Greg do the work for you must be the icing on the cake as it were. When I took on my current 928 over 10 years ago to put my late S4 motor in it, it was tempting to simply put the motor in the car and hope for the best. Fortunately I was smarter than that, instigated a tentative compression check, No 7 was duff, so we gutted the top end of the motor and dropped the sump but left the bottom end intact just like Greg did here. 10+ years on no real issues to date but the sump gasket is weeping a bit now.
To the OP hopefully you will have many happy years of motoring knowing that a very safe pair of hands has checked it over and sorted it out.
Rgds
Fred
11-02-2016, 05:26 PM
#20
Rainman
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V2, best discussion of GTS piston oil hole drilling is likely here:
https://rennlist.com/forums/928-foru...s-pistons.html
https://rennlist.com/forums/928-foru...s-pistons.html
I was thinking they had modified the oil drain back holes from head-block-sump...never thought about pistons.
11-02-2016, 08:27 PM
#21
Rennlist Member
This is how it goes when dealing with a German....who will never admit that they did anything wrong.
They will insist that the real problem is that the oil control rings are in the wrong place in relationship to the other rings due to some harmonic or frequency that they have found, previously unknown to all others. They will redesign the piston, moving the rings, a bit. The oil drain back holes will magically appear in the redesign, but will not be talked about. All parties will know what the problem was and what the solution was, but they will never talk about it. It's the German way.
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greg brown
They will insist that the real problem is that the oil control rings are in the wrong place in relationship to the other rings due to some harmonic or frequency that they have found, previously unknown to all others. They will redesign the piston, moving the rings, a bit. The oil drain back holes will magically appear in the redesign, but will not be talked about. All parties will know what the problem was and what the solution was, but they will never talk about it. It's the German way.
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greg brown
11-04-2016, 11:46 AM
#23
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A few more photos of the process here. Also a bit of feedback on some of the posts here. Yes, the pics of the head gaskets are scary. I guess I was lucky as the oil was pristine (no water), there were no head gasket leaks or loss of compression that I could tell, and the motor ran fine. Greg did note some concern about corrosion when he pulled the water pump, and what the heads might look like. However when the heads did come off the concern went away. While the heads did require some welding Greg never categorized the deterioration as anything but what he usually sees. This was supported by no additional costs beyond what he had estimated for normal repairs prior to pulling the heads.
I appreciate the comments and feedback as I constantly learn more about the cars.
I appreciate the comments and feedback as I constantly learn more about the cars.
11-05-2016, 11:19 AM
#28
Race Car
Beautiful work!
Did you put the stock cams back in, or did you opt for GT or S3 cams?
Did you put the stock cams back in, or did you opt for GT or S3 cams?
11-06-2016, 09:55 AM
#29
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The stock cams went back in. We did discuss performance modifications ranging from headers and custom exhaust to a stroker motor. In the end I wanted to keep the car original.
A few more photos showing various some underside repairs/additions. These included upper and lower ball joint boots, tie rod assemblies, sway bar drop links, shocks and dust covers, CV joint boots and new front belly pan (now both pans have the correct fasteners).
After all of the work was done Greg drove the car for about 150 miles and the result is that the car is now properly sorted. The car went back on the lift several times as minor items were addressed. His attention to detail is impressive. He even noticed that a dust cap for a brake bleeder and a holder for an ABS sensor cable were missing and replaced them.
I apologize for the rotated pics; can't figure out why these appear that way.
A few more photos showing various some underside repairs/additions. These included upper and lower ball joint boots, tie rod assemblies, sway bar drop links, shocks and dust covers, CV joint boots and new front belly pan (now both pans have the correct fasteners).
After all of the work was done Greg drove the car for about 150 miles and the result is that the car is now properly sorted. The car went back on the lift several times as minor items were addressed. His attention to detail is impressive. He even noticed that a dust cap for a brake bleeder and a holder for an ABS sensor cable were missing and replaced them.
I apologize for the rotated pics; can't figure out why these appear that way.
11-07-2016, 02:57 PM
#30
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Absolutely beautifully cleaned engine!!!
OK Greg, besides elbow grease what product(s) do you use on the exterior of the block to get it so clean?!?! I've got hours and hours into cleaning mine and while it looks good, it's nowhere even close to that! Wow!!
OK Greg, besides elbow grease what product(s) do you use on the exterior of the block to get it so clean?!?! I've got hours and hours into cleaning mine and while it looks good, it's nowhere even close to that! Wow!!