Balance shafts
#91
Thanks for the pics, Gage. Really helps a lot as to where to look, while down in the "black hole"! I'll also check from under the car to see if I can see it better. I'll check my WSM..Maybe I missed copying a page or two. Both shafts are at the engine shop now, verifying that the bearing surfaces are parallel. Fingers crossed.
Thanks for the offer Phil. I'll consider that if I need the shafts..What is the story on the plastic baffles that Tempest referred to on his post? I only have the early (82-85) PET, so those aren't listed, and the PET pic doesn't show them either. Is this something I should consider since I'm "in there" already? Thanks!!
Thanks for the offer Phil. I'll consider that if I need the shafts..What is the story on the plastic baffles that Tempest referred to on his post? I only have the early (82-85) PET, so those aren't listed, and the PET pic doesn't show them either. Is this something I should consider since I'm "in there" already? Thanks!!
Last edited by Tiger03447; 04-14-2021 at 08:43 AM. Reason: Additional info
#95
Here are a couple pics stolen from some ads on E-Bay illustrating the difference between the late and early balance shafts. Notice the counterweights on the later shafts have a plastic baffle/shell/what ever bolted to the back side of them. They can not be added; you would have to swap the whole shaft. I'm not 100% they'll interchange, but for $27.00 delivered it's worth a shot.
Porsche 2.5L 924S 944 951 Turbo Upper Balance Shaft | eBay
Porsche 2.5L 924S 944 951 Turbo Upper Balance Shaft | eBay
#96
Thanks, Tempest! Are you going to add these to your engine? I would also like to now if I went with these, that the bearings might have a different p/n as well? Perhaps there were diameter changes to the bearing surfaces too? Interesting. But now, I just want to get it back together and running. Perhaps next week I can start on the reassembly depending on the shape mine are in. Wait and see..hide and watch..carefully.for now.
#97
Well guys, the mystery is finally solved. apparently, yours truly bolted the wrong nose to the wrong cover. Which bound everything up. Apparently the problem is solved with all the bearing surfaces are parallel. Hopefully, I'll get a chance to re-install on Tuesday..I'll be torquing and spinning to insure that all stays proper and functioning. I'll keep you posted as things progress. Thanks for everyone's help with this situation. Thank Goodness for R-List and all the helpful people on here !!
Last edited by Tiger03447; 04-17-2021 at 06:20 PM. Reason: Additional listing
#100
Guys..since i don't have the housings (covers) right in front of me, I don't know. I do know, however, if you get the upper housing and try to put the lower "nose" on it, it will lock right up. I would suggest only doing one at a time, with it's corresponding nose. Otherwise, you'll have to put a series of marks on each one to keep them in the correct order for re-assembly. Also, there were some guys on the 944S forum that were "talking" about the rear BS bearings. Apparently, there was a change in the bearings in '87. Seems that the '87 bearings and the early bearings are different sizes. In trying to use the wrong bearings in his '86 944 one guy cracked a cover...not realizing the size differences. Glad that didn't happen to me. Hopefully all will go togther without further problems.
#101
Presumably the nose piece (part 17 on the drawing posted a bit earlier in the thread) is align-bored with the block and cover -- so you'd think it would be stamped.
I might go have a noodle around on my car and see if I can find a number on it....
I might go have a noodle around on my car and see if I can find a number on it....
#102
The front covers for the upper and lower balance shaft housings are entirely different from each other. The lower cover has mounting for the power steering pump as part of the casting. I don't now if early cars without power steering are the same but regardless are designed to be concentric to the block / cover assembly.
#103
Gage and others: Yes, both of the front covers(noses) are entirely different. At least on my car, w/o power steering.. However, much my chagrin, I have found that they should be kept with their appropriate covers (rear housings). There are no markings at least on my parts that would maintain nose-housing integrity unless put there at time of disassembly. This is very true if you have the housings sent out for powdercoat...like I did. Which is another cause of confusion on this point. Point well taken when disassembling almost anything these days...especially on these cars..just saying.
#105
The balance shaft side housings are number stamped, that identifies their placement. the front (nose) housings are unique to their location. If these two statements are understood and followed, they will be correctly oriented.
Note that the nose housings must be installed, finger tight, before the side housings are torqued.
Note that the nose housings must be installed, finger tight, before the side housings are torqued.