Notices
928 Forum
Sponsored by:
Sponsored by: 928 Specialists

'86 Oil Pump Seal Failure

 
Old 02-19-2019, 04:31 PM
  #1  
buccicone
Addict
Rennlist Member
Thread Starter
 
buccicone's Avatar
 
Join Date: Oct 2010
Location: Centerburg, OH
Posts: 1,113
Default '86 Oil Pump Seal Failure

After 60 miles the new oil pump seal failed. Checked with Roger if there were any issues and there are none. As far as I know I didn't screw up the installation. Used assembly lube on the seal and oil pump shaft. It really got chewed up. The thin washer closest to the pump was there. I did remove the seal spring that was in picture #2. The seal was seated flush to the oil pump housing. I've done this before. Any suggestions?


buccicone is offline  
Old 02-19-2019, 06:20 PM
  #2  
Mrmerlin
Petie3rd
Rennlist Member

This Post Sponsored by:
Dow Corning« & DeoxIT«
 
Mrmerlin's Avatar
 
Join Date: May 2004
Location: Philly PA
Posts: 22,612
Default

based on what happened and the first picture,
the seal was not flush,
see the top edge.
It appears to be be under the face of the pump thus its at an angle, as compared to the lower edge of the seal

Since the inner seal area came out it also appears that the sealing area was pushed out of place when the shaft went through.
Any chance you left the 1 MM spacer washer on while putting in the shaft?

NOTE if you are installing the steel gear then the 1 MM washer is deleted its only used with the aluminum gear.
NOTE the aluminum gear was superseded to the steel version, as it was found to crack.

On the last picture the seal wall is deformed on the left side this needs to be made flush again a jewelers file will make it so.
also on the right side the seal wall appears to have a part of the sealing surface gouged out thats not good.
It appears that some heavy handed seal removal techniques were used to extract the old seal.
rework will be required to fix the sealing surface of the new radial seal.

When fitting the gears they should have the dots in the gear faces facing the engine block.

I use STP oil treatment on the shaft and the sealing lip and coat the gears of the pump and turn it before installing it,
I use DC 111 on the pump O rings

Last edited by Mrmerlin; 02-19-2019 at 06:37 PM.
Mrmerlin is offline  
Old 02-19-2019, 07:03 PM
  #3  
buccicone
Addict
Rennlist Member
Thread Starter
 
buccicone's Avatar
 
Join Date: Oct 2010
Location: Centerburg, OH
Posts: 1,113
Default

Actually the picture is a better visual than with my eyes. The flushness of the seal was my first thought of what happened. Thanks Stan.
buccicone is offline  
Old 02-19-2019, 08:05 PM
  #4  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

If you install the seal into the pump body, before the shaft of the oil pump gear is installed, the relatively square end of the shaft can/will turn an edge of the seal inside out.

Super common and easy to not see, when it happens.

Porsche makes a set of special tools (and installs the seal after the entire pump is installed on the engine), for a reason.

Those burrs on the chamfer of the oil pump body (where the seal has to slide in) aren't going to help, either.
__________________
greg brown




714 879 9072
[email protected]

If the kids keep breaking a crowbar in the sandbox, sometimes it is easier to just give them a stronger crowbar, instead of trying to figure out what they are doing in the sandbox.
GregBBRD is offline  
Old 02-19-2019, 08:42 PM
  #5  
buccicone
Addict
Rennlist Member
Thread Starter
 
buccicone's Avatar
 
Join Date: Oct 2010
Location: Centerburg, OH
Posts: 1,113
Default

I’m sure I had the shaft of the pump installed before installing the seal. Since it is on the engine, I will install a new seal from there. I saw the burrs also. Were there before.
buccicone is offline  
Old 02-19-2019, 08:49 PM
  #6  
rjtw
User
 
Join Date: Oct 2002
Posts: 498
Default

Not to hijack this thread, but I JUST pulled my oil pump off the block. I have a new shaft seal, but my old one isn't leaking. It's original 1983. I could just change the pump body seal and the three bolt o-ring seals. Thoughts from the experts on whether I should change the shaft seal vs leave the original?

No special tools here but it's clear that mounting square and flush is critical. Perhaps a simple tool could be devised from hollow tubing of the appropriate diameter to aid installation of the shaft once the seal is in place to avoid lip rollover? STP standing by!
rjtw is offline  
Old 02-19-2019, 09:07 PM
  #7  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

Originally Posted by buccicone View Post
Iĺm sure I had the shaft of the pump installed before installing the seal. Since it is on the engine, I will install a new seal from there. I saw the burrs also. Were there before.
Installing the seal once the shaft is in place makes "folding" the lip even easier, without the special tool.

I, personally, never use the special tool. I prefer to install the seal and get it square in the bore of the pump, with the oil pump in my hand. I then lube the edge of the seal and the shaft of the pump and "twist" the shaft of the gear once it reaches the seal. I then inspect the seal to make sure the inner lip did not "invert"....it's obvious to see the problem, with close inspection.

GregBBRD is offline  
Old 02-19-2019, 09:08 PM
  #8  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

Originally Posted by rjtw View Post
Not to hijack this thread, but I JUST pulled my oil pump off the block. I have a new shaft seal, but my old one isn't leaking. It's original 1983. I could just change the pump body seal and the three bolt o-ring seals. Thoughts from the experts on whether I should change the shaft seal vs leave the original?

No special tools here but it's clear that mounting square and flush is critical. Perhaps a simple tool could be devised from hollow tubing of the appropriate diameter to aid installation of the shaft once the seal is in place to avoid lip rollover? STP standing by!

35 year old seal? No question, replace it while you are there. See instructions above for a technique.
GregBBRD is offline  
Old 02-19-2019, 09:11 PM
  #9  
rjtw
User
 
Join Date: Oct 2002
Posts: 498
Default

Thanks Greg, and your how-to makes perfect sense.
rjtw is offline  
Old 02-19-2019, 09:23 PM
  #10  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

BTW.....the factory oil pump tools are "T4", which is German for "We don't have any more and we have zero plans on making them again".

I'd never even seen one of the factory installation tools until Rob Edwards brought one over, when we were assembling one of his engines.

........"What the heck is that for?"
__________________
greg brown




714 879 9072
[email protected]

If the kids keep breaking a crowbar in the sandbox, sometimes it is easier to just give them a stronger crowbar, instead of trying to figure out what they are doing in the sandbox.

Last edited by GregBBRD; 02-19-2019 at 10:44 PM.
GregBBRD is offline  
Old 02-19-2019, 09:37 PM
  #11  
rjtw
User
 
Join Date: Oct 2002
Posts: 498
Default

I'm going to hijack the thread again, while on the subject of seals. I ALSO am planning to replace the crank seal while I'm here, again still original. I plan to use the PVC-pipe or pill-bottle method of installing the seal, again ensuring it's square and flush. The OD of the crank seal is just under 3.4". Greg, do you have any further words of how-to wisdom for installing the crank seal? Some old and conflicting info here: https://rennlist.com/forums/928-foru...placement.html THANKS!

Last edited by rjtw; 02-19-2019 at 10:02 PM.
rjtw is offline  
Old 02-19-2019, 10:41 PM
  #12  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

Originally Posted by rjtw View Post
I'm going to hijack the thread again, while on the subject of seals. I ALSO am planning to replace the crank seal while I'm here, again still original. I plan to use the PVC-pipe or pill-bottle method of installing the seal, again ensuring it's square and flush. The OD of the crank seal is just under 3.4". Greg, do you have any further words of how-to wisdom for installing the crank seal? Some old and conflicting info here: https://rennlist.com/forums/928-foru...placement.html THANKS!
I use the factory installation tool, which has it's own set of "issues".

The front crankshaft seals do not seem to have a chronic leakage issue, like flywheel seals.

Make sure the "slot" in the aluminum (which is used for removal of the old seal) doesn't have any sharp edges sticking up from the removal process of the old seal. (Usually a screwdriver and a hammer.) You can deburr that edge with a small knife, if necessary. The crankshaft has a large seal entry ramp on it, for the seal, so it's pretty difficult to "fold" the edge of the seal or have the edge deform and allow the inner spring to come off (this is common on the flywheel side.) The current seals I've been using seem to go in "pretty loose", but I've had no issues with them coming back out.

Lube it up (I use Wurth HSS on the OD of all seals and o-rings and a thin layer of Porsche factory high pressure grease on the sealing lip), get it square at the original depth, and you will be fine.
__________________
greg brown




714 879 9072
[email protected]

If the kids keep breaking a crowbar in the sandbox, sometimes it is easier to just give them a stronger crowbar, instead of trying to figure out what they are doing in the sandbox.
GregBBRD is offline  
Old 02-19-2019, 11:11 PM
  #13  
rjtw
User
 
Join Date: Oct 2002
Posts: 498
Default

Thank you!
rjtw is offline  
Old 02-25-2019, 09:15 PM
  #14  
buccicone
Addict
Rennlist Member
Thread Starter
 
buccicone's Avatar
 
Join Date: Oct 2010
Location: Centerburg, OH
Posts: 1,113
Default

Originally Posted by GregBBRD View Post
If you install the seal into the pump body, before the shaft of the oil pump gear is installed, the relatively square end of the shaft can/will turn an edge of the seal inside out.

Super common and easy to not see, when it happens.

Porsche makes a set of special tools (and installs the seal after the entire pump is installed on the engine), for a reason.

Those burrs on the chamfer of the oil pump body (where the seal has to slide in) aren't going to help, either.
Re-did the oil pump seal. At first on the engine. Used a mirror and saw just this: The inside of the seal turned inside out somewhat and could actually see the seal spring. Took the pump out to the bench and removed the shaft and reset so it was not inside out. Oil leak appears to be gone after 22 mile run. Thanks for the info guys. Greg, did you get my email?
buccicone is offline  
Old 02-25-2019, 11:29 PM
  #15  
GregBBRD

Rennlist
Basic Site Sponsor

 
GregBBRD's Avatar
 
Join Date: Feb 2005
Location: Anaheim
Posts: 9,686
Default

Originally Posted by buccicone View Post
Re-did the oil pump seal. At first on the engine. Used a mirror and saw just this: The inside of the seal turned inside out somewhat and could actually see the seal spring. Took the pump out to the bench and removed the shaft and reset so it was not inside out. Oil leak appears to be gone after 22 mile run. Thanks for the info guys. Greg, did you get my email?
Didn't see it, yet.

Did you send it to my "frequently read" email ([email protected])

At any rate, because of my complete frankness and a complete lack of any sort of a filter, I frequently **** people off, even when I'm just trying to help.....

I'll apologize up front.

I'm sorry....I've been this way, my entire life.
__________________
greg brown




714 879 9072
[email protected]

If the kids keep breaking a crowbar in the sandbox, sometimes it is easier to just give them a stronger crowbar, instead of trying to figure out what they are doing in the sandbox.
GregBBRD is offline  

Thread Tools
Search this Thread

Contact Us - About Us - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: