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Bizarre oil pump problem

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Old Jun 6, 2014 | 08:52 PM
  #16  
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And yes it ran fine before the belt broke.
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Old Jun 6, 2014 | 08:55 PM
  #17  
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i wonder if the shaft does not have a slight bend after the break.....
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Old Jun 6, 2014 | 08:56 PM
  #18  
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That is the only thing past oil pressure relief that I would guess.
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Old Jun 6, 2014 | 09:23 PM
  #19  
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please explain how the belt broke? what else was damaged.

If this pump came from the engine and it was running properly before the belt broke then it should work properly.
possibly you have not put the pump back into the engine properly.
hence the request for picture posting of the pump prior to removal from the engine
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Old Jun 6, 2014 | 09:41 PM
  #20  
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Originally Posted by Mrmerlin
please explain how the belt broke? what else was damaged.

If this pump came from the engine and it was running properly before the belt broke then it should work properly.
possibly you have not put the pump back into the engine properly.
hence the request for picture posting of the pump prior to removal from the engine
The pump is off of the motor at this time.

I'm waiting for a new seal and, maybe a new pump. When I get that, or those things, I'll post a picture of exactly how I did it.

From what I ascertained, the belt broke because of a bad roller. It had multiple flat surfaces...very weird. No idea how that happened. Other things damaged - a couple timing belt covers, timing belt "guide" (part 928 105 567 01) got pretty bent up. Water pump was not bad, but replaced it anyways. Cams fine. Cam gears were a bit worn, replaced with early steel gears. Crank gear fine, oil pump gear fine.

Thanks for all your help.
Royal
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Old Jun 6, 2014 | 10:29 PM
  #21  
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Doesn't the lip of the seal have to be clearanced around the shaft? Meaning when the shaft is inserted through the seal, and the pump is bolted to the block, I took a dental tool (not a pick, but a wider flat one with a blunt tip) and very gently ran it around the surface of seal lip (that contacts the shaft) to make sure the entire surface of the lip was on the wide part of the shaft, and not being pushed forward onto the narrower portion by the wider portion behind it.
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Old Jun 7, 2014 | 01:15 AM
  #22  
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after dressing the end of the pump shaft,
dab some STP onto the seal edge and the shaft

NOTE when fitting the radial seal it gets seated flush with the housing.

NOTE gently install the shaft while adding a slight twist,
this should let the shaft smoothly slide over the end of the shaft
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Old Jun 7, 2014 | 04:48 AM
  #23  
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It's likely that the seal either is having the assist spring fall off during install, or the seal isn't getting enough lubrication and is failing due to that.

When you install the seal take some thin cardboard and make more of a cone to slide the seal on to ensure that the spring doesn't pop off.
Lube both the inside, and outside of the sealing lip with grease (more is better than less)
As well, I would be using much higher than 600 grit paper. I would be polishing with around a 1000 grit with oil the ensure it is a perfectly smooth polish.
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Old Jun 7, 2014 | 05:35 AM
  #24  
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Here is my GTS installed with a new oil pump seal. Actually a very straight forward job...
Attached Images
File Type: jpg
Oil pump.jpg (150.1 KB, 283 views)
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Old Jun 7, 2014 | 11:18 AM
  #25  
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Covered above but I see a few potential problems:

Seating the seal too deep and the lip gets eaten away.

Wrong pump and no drain-back hole. (BTDT!)

Shaft isn't smooth. Buff with emery cloth or 1000 grit sandpaper.

Bad installation with lip distorted, spring falling off or no initial lube.
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Old Jun 7, 2014 | 12:37 PM
  #26  
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Thanks for the help everyone. I am happy to know that the general consensus is improper seal installation as opposed to a damaged oil pump. Yesterday I began to think that when the timing belt broke that it torqued the oil pump in a bizarre way and perhaps the shaft was damaged in some fashion that I wasn't able to see with the naked eye. I also then began to think that this is unlikely because this is presumably a very hardened metal which usually is more prone to cracking than bending (but what I do I know, I'm not a metallurgist... I digress perhaps...)

I've installed this kind of seal before but perhaps I am in fact missing some small detail.

I'll report back once I get another seal and install it. I've tried sourcing it locally to no avail so the only option is to order, unfortunately.
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Old Jun 10, 2014 | 08:44 PM
  #27  
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OK guys - still have a leak here.

Just installed a new one (now the 4th) - burst pretty quickly and started throwing oil.

Have followed the following steps/taken the appropriate precautions:
Cleaned shaft with fine grit paper
Grease on install
Twist on install
New o-rings
Proper cupped washers
Proper length bolts
NO 1mm spacer in between gear and pump
Pump has no play
Appropriate orientation

I'm going to check the oil pressure relief valves later/tomorrow.
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Old Jun 10, 2014 | 09:17 PM
  #28  
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Take a pic with the gear off, maybe someone on the list will notice something you may have missed.
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Old Jun 10, 2014 | 10:13 PM
  #29  
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This is not a common leak.

Any chance you got the wrong size/POS seal, from the same place, three times?

Could you be installing the seal the incorrect direction? (Sorry, you seem like you know your stuff, but I have to ask.)

I use a Victor Reinz seal (81-15292-30), which is 20 x 30 x 7
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Old Jun 11, 2014 | 01:01 AM
  #30  
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As Greg has suggested this isnt a common issue.

please post a picture of the pump installed in the block.
your pump should look like the one Shocki has posted in post 24.
Did you use Dow Corning 111 on the pump O ring?.

Is it possible that the oil is not leaking from the radial seal?

you could install the pump then the shaft nut with a few washers ,
NOTE dont put on the gear,and then turn the nut with a drill to see where the oil is leaking from

Last edited by Mrmerlin; Jun 11, 2014 at 02:01 AM.
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