ayglass

After changing cams and rockers to address a lubrication problem with #2 intake (the oiler was plugged and caused some damage). While the car was down I took care of a few other things that were nagging problems and put in a used replacement scavenge pump (cleaned and appears Ok).

Upon starting the car I participated in the most thorough mosquito abatement program the South has ever seen! A significant amount of oil came out the tailpipe both burned and liquid. I figured that the turbo oil seal had given up while the car was down and that I would need to address this with a new or rebuild turbo. I ran the car until it was warm and kept the revs up to break in the new cams correctly. I then dumped the oil and replaced the filter and oil. When I tried to restart the car I got a "chunk" sound when I hit the starter. My first thought was the tensioners or chain had failed since I had just timed the cams and had all of that apart. I immediately took the key out and did not try to restart. I tried to turn the engine by hand and it would back up a little but would not turn forward.

Upon taking it apart I got a large amount of oil from the turbo tank (see photos that's a 22mm wrench for comparison) and also quite a lot of oil in the intake. I now started to think hydraulic lock. I took out the plugs and number 4 was full of oil. It ran out when I turned over the engine by hand. The engine appears to be ok at this point.

My questions are #1 did I damage the engine with that brief attempt to start it full of oil? (I wasn't on the key for a fraction of a second before I froze) and #2 do you guys think that the scavenge pump is really the culprit given the amount of oil that came out?

I am hoping I don't have to take the engine apart again!

Mods include k27-2700, kokeln IC, SC cams, GHL exhaust, 1 bar spring, etc...

equality72521

WOW!!! I can't offer much help but here is a bump for good luck. I hope this works out well for you.

911rudy

Man! Tough break. I think you may be right about the scavenge pump. The engine pump is doing its job but the oil is not being removed. Did you check the tank to see how much oil was in it after it wouldn't start? If it was way low then it would point to the s pump. Hope you find out soon. Good luck.

ayglass

At one point I couldn't see the tach from the driver's seat in an open car port! I didn't actually check the oil tank after the break-in run as the problem hadn't surfaced yet. I just dumped the oil, changed the filter and refilled. From what hit the ground when I opened the turbo tank I became concerned that the scavenge pump wasn't working. I just don't have a good reference for how much typically lives in that little tank. I don't recall it dumping so much the previous times that I've opened that line. I was running it at ~2k for break in, so I would have thought the scavenge pump would have been spinning fast enough to pull out the oil. I'll pull the pump and look it over. I still have the original one (which leaks), so I can rebuild that one and put it back. Pretty soon I'll have an extra turbo in parts on the shelf!

WERK-I

Are you sure you got the oil tank hoses hooked up to their proper locations? If there is oil ABOVE the throttle body, then that oil is coming directly from the oil tank.

DonE

Overfilled the oil tank?

That is a lot of oil - wow. Be careful of hydraulic lock in the cylinders.

ayglass

So, the rabbit hole gets deeper... But I think I'm getting somewhere now!

The top cam is the modified 911SC cam that came in the car. The bottom cam is a the factory 930 cam. The boss on the top one is 48mm and the boss on the factory one is 25mm. I ordered the replacements from Webcam as "cams for an '86 turbo with an SC grind" I'll bet that they used the correct factory blank.

When I installed the new cams I put them back the way they came out, hex screws in the end and no pulley. I measured an extra air pump pulley this evening and it just happens to be about 23mm deep. I haven't taken the car apart yet, but I'll bet that my scavenge pump is about 23mm away from being driven!

thomas682

Andy,

Send me a PM if you want a hand with the disassembly or need another set of Turbo/SC grind cams for comparison. I live about 20 minutes south in Gainesville.

Regards,

thomas

WERK-I

Yep, that would do it! Btw, did you remember to put the little check valve ballbearing in the fitting that has the oil feed line to the turbocharger?

ayglass

Hey thanks for the offer Thomas. We really have no excuse for not getting together for a visit. My parents live in Gainesville so I am in the area frequently.

Dave, I didn't actually look for the check ball. I swapped out the sender and breather gasket while the engine was out per Wayne's book, but didn't look for the ball. I assume that it's down in the block and that taking just the sender out doesn't disturb it? I hope I don't have to go after that again now that the engine is back in the car :-)