1987 Porsche 944 turbo crankshaft problem.
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1987 Porsche 944 turbo crankshaft problem.
I have a 1987 944 turbo I am rebuilding.
I got a crankshaft for cheap out of a 1983-85? 944 N/A.
Are the bearing columns the same size as my crankshaft?
Questioning this because I had it lightened and installed it. I torqued the crank case to the specs provided in a shop manual. When I did, the crank was seized. I loosened it back up and it was free. This is with brand new Glyco bearings.
Thanks for the help. I have to get to sleep now. I will check when I wake up.
I got a crankshaft for cheap out of a 1983-85? 944 N/A.
Are the bearing columns the same size as my crankshaft?
Questioning this because I had it lightened and installed it. I torqued the crank case to the specs provided in a shop manual. When I did, the crank was seized. I loosened it back up and it was free. This is with brand new Glyco bearings.
Thanks for the help. I have to get to sleep now. I will check when I wake up.
#4
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Are your glycos made in Germany or Mexico? Mexican bearings are sometimes thicker on edges due loose quality control. You wouldn't be the first to have this problem.
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The front bearing is correctly placed and it spins fine (not too tight). Perhaps I am torquing the plate too much? The final stage is 54lb/ft I believe, for the larger nuts. I will check on the manufacturer location, but I am pretty sure its germany. I ordered from Lindsey Racing. It also came with an extra front bearing, for some reason.
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#8
Thats funny, I also had an extra front bearing in my main bearing kit. Confused the heck out of me. I have been reading that sometimes sticky assembly lube can make it seem like it is seized. I'm sure it would be compounded by cold weather too if you have that. Check for foreign debris that may have gotten in there too. Did you measure the clearance torqued down?
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No I have not measured the clearances. Can I get a quick how-to on that? I'm using black assembly lube, it is fairly sticky. Maybe I'll take down again and just use motor oil.
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Try with only two bearings at far ends of crankshaft then add one by one and see when the crank seizes.
Glyco might be your problem since they sometimes sell you garbage. That's why porsche checks every bearing before packing it to porsche box.
You can also measure clearance the easy way with plastigage as suggested, here is how: http://www.plastigaugeusa.com/how.html
Don't you towel out on us!
Glyco might be your problem since they sometimes sell you garbage. That's why porsche checks every bearing before packing it to porsche box.
You can also measure clearance the easy way with plastigage as suggested, here is how: http://www.plastigaugeusa.com/how.html
Don't you towel out on us!
Last edited by Voith; 03-29-2016 at 10:12 AM.
#13
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you put a piece of it on the crank, then install the crank and tighten the nuts down like normal, then undo it all and measure how wide the piece got squished...that will tell you your bearing clearance.
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So, if they are too thick, how could they be corrected? Just scrapped and replaced? Should I have just bought Porsche brand ones to begin with then? Thanks for all the help fellas. I love this place.
#15
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Ideally you would place it on the top and at bottom of the journal and you would not spin the crank when torqued up to spec. That way you would know if you are journal is round (rough idea). More work, as you have carefully lift the crank out each time, but 90% of winning the battle is in the preparation...