bgd73 Posted November 4, 2006 Share Posted November 4, 2006 I just took apart a 1993 oil pump, and was reading up on my 1987 GL. I found a technical service bulletin in regards to the oil pump shaft gasket allowing for aeration.1990-1994 wasn't listed (the loyales did something different yet again- I want to use my 1993 pump, freshly sealed, on my 1987 (if it is the same "B" tolerance- hopefully "down the middle" will work). The easy way to verify for aeration was check the oil dipstick for tiny bubbles. sure enough, I have an hla that won't stop and air bubbles. there is also a drop right below oil pump. anyway, when I get to the timing belts, I want to swap stuff. Any advice? The 1993 sending unit angle is different than my 1987, and that is all I have noticed.An "A" tolerance will not take a B, but a C will. Will know if I can do this soon. My deeper question is about the oil pump shaft. Before finding out for myself next week, I was hoping a pro could tell me if the shaft on my 87 is the same as my 93. The 93 has a ridge near the problem seal intentionally engineered, I am unsure of the 87, as I have never taken an older one (pre 1989) apart.The 1993 pump was flawless right up until the day I took it apart with 161k miles and 14 years old. The 87 is all done. needs pump work. Oh, I made a web page primally in awe of the "trochoid pump" design at my website http://93loyale.com/opump.html In a way I am hoping it is more than the gasket design that changed from 1989 into the Loyales. The seal alone being different doesn't explain the petrified gasket keeping a seal in my 1993. I am almost certain the shaft changed a bit from oem design. Anybody know? p.s. No comments on my oil pump spring washer please Quote Link to comment Share on other sites More sharing options...
daeron Posted November 5, 2006 Share Posted November 5, 2006 thanks for the post... now to look up "trochoid pump" on wikipedia.. i have NEVER seen a pump designed like that. (obviously havent torn down my engine yet) I love learning Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 5, 2006 Share Posted November 5, 2006 on your webpage you mention the shaftseal as the typical problem area. they very rarely fail, i've never seen one leak. the problem is the kinked port of the mickeymouse gasket. that kink is the issue on all EA82 (and ER27 and EA82T) oil pumps. if that pump wasn't "ticking", then it was only a matter of time before it would start. Quote Link to comment Share on other sites More sharing options...
bgd73 Posted November 5, 2006 Author Share Posted November 5, 2006 on your webpage you mention the shaftseal as the typical problem area. they very rarely fail, i've never seen one leak. the problem is the kinked port of the mickeymouse gasket. that kink is the issue on all EA82 (and ER27 and EA82T) oil pumps. if that pump wasn't "ticking", then it was only a matter of time before it would start. I did get ticks once and awhile while oil was full, that may explain it. the funny part of that gasket kinked is no external leaks- not a single drop.I figured the location of kink was nearly impossible by reason to get to the outside world anyway. It did block part of the oil port however. I had to tighten the oil pan after the 12 th year, and even then the leak was minimal. The technical bulletin for the oil pump was at an auto parts web site, that is what lead me to benz-arckley gaskets. They can petrify and stay sealed, the 87 I just purchased is not that lucky. I hope to see a "B" stamped on the shaft and round gear as it will be a oem match, from my 93 to the 87,no risk to swap. My old 87 did leak for awhile, but my oil choice must have saved it (castrol High mileage) . There is no return for decent on this one however. . Oh, I did find some bad news- one cyl head has asv, the other appears to be an spfi, and the y-pipe is lower on one head than the other, but exhaust sealed. I hope that isn't the problem. When I first filled this car to get it home, it was very quiet- so there is no doubt an oil relation. I bought some "mag" engine cleaner for the base and will run that today to see what happens, and swap it to my favorite oil. A 30 mile run in the 70's with louder exhaust, and the oil drop I found near pump is staying just that. No excuses for me tho, it really does need something. daeron: That pump is a strange thing to watch. Just when I thought rotary engines and limited slip differentials were strange, that pump is even more so . It even has a gear ratio from the outer to inner shaft, I didn't count what it was, but to look at seems as it would be 1 to 1 and it really isn't. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 5, 2006 Share Posted November 5, 2006 the funny part of that gasket kinked is no external leaks- not a single drop.I figured the location of kink was nearly impossible by reason to get to the outside world anyway. It did block part of the oil port however. actually they often don't leak externally. it's not that it blocks the oil port. it's that the suction is going to pull air in through that gap created where the gasket is compromised. that mixes air with your oil which your HLA's will not thank you for (hello TOD!). air is compressible and oil is not...hydraulic valve lash adjusters don't like compressible stuff in them. i've probably seen at least a half a dozen gaskets pictured exactly as you have shown, and posted pictures of them before as well, one port sucked in. this is the primary/standard cause of ticking. as for the "B" stamp on your rotor. i'm fairly confident that's what you'll find. i think that's the standard OEM factory install, any others are for replacement/clearance issues and i think are seldom used. pretty sure all the XT6's i've ever done are all stamped "B" as well. Quote Link to comment Share on other sites More sharing options...
bgd73 Posted November 5, 2006 Author Share Posted November 5, 2006 actually they often don't leak externally. it's not that it blocks the oil port. it's that the suction is going to pull air in through that gap created where the gasket is compromised. that mixes air with your oil which your HLA's will not thank you for (hello TOD!). air is compressible and oil is not...hydraulic valve lash adjusters don't like compressible stuff in them. i've probably seen at least a half a dozen gaskets pictured exactly as you have shown, and posted pictures of them before as well, one port sucked in. this is the primary/standard cause of ticking. as for the "B" stamp on your rotor. i'm fairly confident that's what you'll find. i think that's the standard OEM factory install, any others are for replacement/clearance issues and i think are seldom used. pretty sure all the XT6's i've ever done are all stamped "B" as well. Excellent. I am going to swap then. This brought back a few years to my friends 87. His was only 9 at the time needed more parts than I have ever seen a sube need. The tod problem was one of them. they resorted to fixing the outside seal behind the belt gear- the car started smoking and using alot of oil (very rare smoking ea82) 181k the motor was all done. This was after the fforts of fixing the pump. I am hoping at 104k I can swap out for the 93. "B" is indeed down the middle, I will count on the swap. The motor flush worked great, now it is just the aeration problem. Sometimes quiet then it sneaks up while pressure is good on new oil - tod shouldn't be happening. I found some dexron2 under the hood, while there is no power steering leak, someone must have used it for the engine- I am guessing the old hillbilly theory that dexron2 swells rubber seals was in action. More reason to scrap the pump. Thanks for imput about the b tolerance- I just learned it in the manual, did not know what happens in the real world mainstream:) Quote Link to comment Share on other sites More sharing options...
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