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Discussion Starter #1
I need to replace my crank pulley as the pulley on the car is wobbling, more so since I replaced the alternator. But before I do, I have questions about the usability of the MTC crank pulley that I purchased.


The seal surface seems rough to me and I am wondering if this will hurt the seal over time?


If you agree that it is too rough, should I sand the surface to polish it?


As you can see from the pictures, there is also surface rust on the seal surface even though it has been stored in the package.
 

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It's impossible to gauge the roughness without touching it. If it were me I'd go at it with abrasive pads, a medium to start and remove the rust, then a fine to polish it up. As a final step, use a fine pad with some WD40 as a lubricant to lift any contaminants. Blast with brake cleaner and install.
 

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Discussion Starter #3
Thanks O2Pilot for the suggestion. I have Scotchbrite and I will try to at least get the rust off.



Here is another picture. The surface looks like it has many grooves, possibly from a lathe? Also there is pitting in the surface. It's been a long time, but I don't remember a Genuine SAAB pulley having grooves like this. Could this possibly be to retain oil or is it just poor quality? Maybe I should have it polished by a machine shop that does crankshafts?
 

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It's a seal, not a bearing, so you don't need a mirror finish. I wouldn't worry about machining marks like that, depending on the depth obviously. Try a coarse abrasive pad, or better some medium emery cloth, if you want to knock them down a little.



The pitting I can see looks very small - it could be more of a concern, but not a big one IMO. If it was deeper than I was comfortable with I'd fill it with JB Weld, sand, polish, and go, but I don't think you need to go that far unless it's a lot worse than I think. As long as you have a regular surface all the way around the seal should be OK.
 

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One could also press on a redi-sleeve (speedi-sleeve)

for about $20 to achieve a mirror finish for seal to ride on. I also bought an MTC 2032 pulley that has grooves that are detectable with a fingernail, but not rusted.
 

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Don't overthink it. Seems to me that you're trying to make a problem when there isn't one. Clean the surface with a Scotchbrite pad to polish it up first.
 

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Discussion Starter #10
Don't overthink it. Seems to me that you're trying to make a problem when there isn't one. Clean the surface with a Scotchbrite pad to polish it up first.

I'm trying to find a simple solution, but when I think back to my water pump/hose manifold job and the resulting leaks that I had to solve afterward - I just want to avoid doing this job twice.
 

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I'm trying to find a simple solution, but when I think back to my water pump/hose manifold job and the resulting leaks that I had to solve afterwards - I just want to avoid doing this job twice.
The two situations are completely different. The water pump system etc is running at positive pressure around 15 psi. The oil seal on the crank is retaining splashing oil vapour in the sump that should be at negative pressure assuming correctly functioning crankcase ventilation.
 

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Discussion Starter #12
The two situations are completely different. The water pump system etc is running at positive pressure around 15 psi. The oil seal on the crank is retaining splashing oil vapour in the sump that should be at negative pressure assuming correctly functioning crankcase ventilation.

I don't mean to compare the two jobs mechanically - I meant that I needed to be sure of the procedure completely to do it right and not have to do it again as I did with the hose manifold.
 

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Discussion Starter #13
I spent at least an hour today polishing the seal surface with abrasives I had on hand. I started with green Scotch Brite and WD-40. That removed the rust but not the grooves I could still feel with my fingernail. I switched to 600 grit wet-dry paper, again lubed with WD-40, and that made a substantial difference in the texture of the metal. I ended with crocus cloth, but not sure if that did anything at all.


There are still pits in the surface that I might be able to get out with further sanding, but I thought that was enough repetitive motion for my arm for one day.


It is at least 95% improved.
 

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