problems after valve adjust
 

I did a valve adjustment, oil change, plug change, distributor cap and rotor change, etc. last weekend on my 1982 911SC and other than my fingers being really cold, it went OK. Monday morning I drove about 45 miles and things seemed fine. When I got to my destination, I checked the oil level and it was full.

Monday evening when I drove home, I heard what I think was valve noises, so I figured I must just have forgotten to sufficiently lock down the valve last adjustment nut or something dumb like that. However, as I got closer to home, the temperature started to climb and the engine ran more and more poorly. It never got into the red, but it was higher than usual and sounded just awful. In addition, I was getting a lot of engine vibration from the pedals.

I limped on home and let it sit overnight. In the morning, I drained the oil again, and re-adjusted the valves. All seemed OK, but #6 and #5 exhaust valves seemed a little tight (I figured that it was probably because my cold fingers had problems feeling the feeler gauge) so I readjusted them. I put it all back together, refilled with oil and didn't drive it until the following morning.

After about 20 miles at mostly highway speed, the engine temp started climbing again and the oil pressure seemed to be too low, so I immediately pulled over and checked the oil. It was low, so I added a quart and also let it cool off for ten minutes. After that, I drove it straight back home, and it was running badly again by the time I got it in the garage.

I didn't retime the engine after I replaced everything -- could that be it? I don't know what the problem could be -- I've adjusted my valves many times before without any problems. What could have changed? What can I check/do/replace?

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Thanks for any help!

Welcome to the board. You don't mention what year your car is but if you were adjusting the valves that narrows it down to a only 30 year window ('63-'94). ;D
Any chance you have a motor with a sump plate ('63-'83) and put the sump plate on backwards?
-Chris

Chris,
Driver's posting says 1982 SC. Interesting problem. Good thought on the sump plate. oil pressure would be non-existant, though, wouldn't it?

Doug

I'd look into what Chris suggested. Also, are you checking the oil level correctly, with the engine running and at operating temp?

Jeff

It's a 1982 911 SC with a 3.0 engine with tensioner upgrade, turbo valve covers and a couple of other things. Hmm. Backwards sump plate is a possibility, since I replaced the sump seal. <goes to garage to check...>

Well, I don't think I made an error -- my recollection was that the drain plug was to the rear of the car, but I can't find a photo of the bottom of this engine to verify and I'd rather not dump out all of the oil (again!) to check. Anybody know for sure?

The thought of running the engine without a working sump kind of makes me sick...

Oh, two other things I should mention -- the engine was rebuilt less than a year ago (by a competent mechanic -- not by me!) and the car had been running relatively well before the adjustment. It was just time to do it according to my calendar.

sump pump
 

OK, I've just verified that my sump plate is installed correctly. Correct me if I'm wrong but it looks from this diagram that the drain plug is indeed facing the back of the car.

Still, it was a very good guess -- matches the symptoms uncomfottably closely.

http://forums.pelicanparts.com/uploa...1107643505.jpg

Interesting. I always thought facing left was correct.

I've got an '84 so I can't help you by looking at mine, but I just looked at a picture in Wayne's"101 Projects..." book on page 19 and it clearly shows the drain plug on the <I>left</I> side of the engine.

Is yours facing aft?

-Scott

Was the engine stone cold before the valve adjustment?

Welcome to the board. I just climbed under my 83SC and the drain plug is on the left (drivers) side.

Check the cap, rotor, and wires (at both ends) to make sure they are on correctly. Pull the plugs and check for fouling or overheating.
Make sure you are checking the oil with the car running, on level ground, and up to temp. Did you adjust the valves STONE COLD? If not, you may have issues there.

My '82SC has drain plug on driver's side.

Drain plug is definately on the drivers side of the engine.

If you are slightly off, that could explain the erratic but not a total loss of oil pressure.

AFJuvat

First off, I want to thank you all for your thought provoking questions and observations. It's nice to have some help with this.

Some answers:
1. Yes, the valves were very cold when I adjusted them. My typical habit is to park the car, jack it up, drain the oil and then do the valve adjustment the following morning. The day I did the valve adjustment it was probably around 0C in the garage.

2. Yes, until earlier this week I have always checked the oil with the car running, warm and level. However it's been a bad week for me, automotively speaking, and while trying to check the oil level in dim light the other morning, I accidentally dropped it into the tank. :( I tried fishing with a magnet and grabbing with a flexible grabber tool, but no luck with either method. I have a replacement dipstick on order from our sponsor.

3. I have seen photos of engines in this era which have the drain plug to the left of the car (driver's side in most countries) but I am quite certain mine has never been that way since I've owned it. Even if it had been installed incorrectly all these years, there was no change that would have accounted for the difference, so maybe it's another thing that might be wrong, but not the thing.

My Porsche manuals are on microfiche so I can't really post them very easily, but they also don't have any clear picture showing the drain plug in the context of the rest of the engine. These manuals show that there was a change for the the 1980 through 1983 models (these manuals were updated in 1984) in the sump plate. Maybe this was one of those changes?

Alternatively, mine really was installed incorrectly all along, but if there was no change, what accounts for the difference in engine performance? As Alice once said in Wonderland, "Curiouser and curiouser...."

Ed

Timing chain will not jump when engine is turned backwards unless there is something radically wrong. Even then I doubt whether it would happen..never seen it on any 911 engine (or any others).

Any chance you left a rag in the engine compartment and the noise and temp increase was due to it being sucked through the cooling fan?

Altered the ignition timing or left something loose?

you said the oil was "full"... Define that and at what temp it was measured at "full"... Where was the dial in relation to the marks...

I would double check the ignition timing (it might have moved when you replaced the rotor and cap) then make sure you put the right spark plugs in it.
Dave

Weird symptoms. It's important not to have the drain plug under the pickup tube for the oil pump. As long as it's not there, it can be basically anywhere.

So, the engine is running fine for the first part and then starts running hotter? Oil pressure should decrease as the engine temps go up...

-Wayne

Britwrench: interesting thought about a wayward shop rag. I checked with a trouble light but saw nothing out of the ordinary. Also, I am very sure I never turned the engine the wrong way.

geof33: I'm going to take a risk and answer without consulting my lawyer. ;) I checked the oil after a 45 minute drive, so the engine was certainly warm. The temp gauge was a bit above the halfway mark, which is the norm for this car, and my definition of "full" is "somewhere between MIN and MAX on the dipstick" when checked with the engine running and the car parked on level ground.

Dave: plugs are Bosch, Pelican part number W5DC, freshly purchased from our sponsor (as were all other parts except the oil).

Wayne: It's nice to see it's not just me who thinks these are weird symptoms!

It's good to check the dumb stuff -- this will probably turn out to be some simple stupid thing; it's just a matter of figuring out what.

Unfortunately, I won't have any time to work on it for a few days, but here's my plan for when I get back to it:

1. drain the oil (for the third time!) and double check the sump plate placement
2. verify the timing
3. put it all back together and test drive

If, as I suspect, the timing is unaltered and OK, and the sump plate's drain plug is not under the pickup tube, anybody have a clue as to what step 4 should be? Any suggestions for alternative plan? In any case, thanks for the brainpower already expended. I'll let y'all know what I find when I figure this out -- or further detailed symptoms if I don't!

Just a shot in the dark here, but you mention alot of vibration in the pedals. I had this problem after my valve adjustment when I mixed up the #2 and #3 plug wires. It still ran, and had good power, but something was definitely not right. I didn't drive it long enough to see if this would cause hi temps.

You say it sounds awful after the valve adjust? What kind of sounds?

If it's valve clatter, maybe you aren't adjusting one of more of the cylinders when it/they are really at TDC.

I know this is unlikely but is there any chance you got the TDC and rotation off when moving from plug to plug?

Good suggestion. I just came back from the garage and verified that the wiring order is correct by tracing each wire and that the #1 plug wire is where it's supposed to be on the distributor.

I just had a strange thought -- could a valve spring break in a way that wouldn't be obvious when I verified the valve adjustments? I've never had a valve spring break, but it seems to me that it would be pretty obvious when you adjust the valves. Is that a correct assumption?

I had a broken valve spring for a while (only the outer spring, inner was still OK). The symptom was a sudden loss of power at 6000 rpm. I've heard that broken valve springs are common on 82 SC's, but doesn't sound like your symptoms.

It sounds like you've verified most of the important stuff. Wayne has forgotten more about these cars than I expect to ever know, but with all due respect to his remarks about the sump plate, I would rotate it. It could be that a part of the curve of that plate is still interfering with the scavenge venturi. At least, if you have noticed lower-than-expected oil pressures at the same time as overheating, then I'm pretty suspicious of that system, and the sump plate orientation.

Wasn't there an update to the sump screen on SC's to avoid a scavaging problem at high speed? If memory serves, the update eliminated the separate drain plug, so if you have a drain plug you DON'T have the update. Even though your symptoms are not happening at high speed they are exactly what you would experience, as others have noted. I would install the updated screen.

I think I probably will rotate the plate. I'll also take digital photos during the process so if it solves the problem, I'll be able to post the definitive answers and y'all will be heroes to the next poor slob who has this problem!

Howard: There was a scavenge pump upgrade I seem to recall having read about in Anderson's Performance book, but my recollection was that it was just upgrading to a 930 Turbo pump. If it was just a sump plate upgrade, I might consider it, but that upgrade (if it's the same one you're thinking of) would be major surgery. If you're thinking of something else, and know more details (or know where I can get more details) I'd be interested.

The early oil starvation problem was solved well before '82. I think it affected the first year or two of SC's ('78 and '79). I think the fix was to go to a different sump screen.

I'll be interested to hear whether the rotating of the sump plate solves the problem. I suspect it will.

The early oil starvation problem was solved well before '82. I think it affected the first year or two of SC's ('78 and '79). I think the fix was to go to a different sump screen.

I'll be interested to hear whether the rotating of the sump plate solves the problem. I suspect it will.

OK, here's what I did. I drained the oil, removed the sump plate and looked it over very carefully. There was a dent in it -- probably the result of my jacking up the car with my shop jack under the engine.
http://forums.pelicanparts.com/uploa...1107926029.jpg

I pounded that out flat, and reinstalled the plate with the drain plug facing to the left of the car and took it for a short test drive of about 10 miles. Everything was fine, but it's not yet a definitive test -- the problem didn't appear until after I had gone over 25 miles. I'll let y'all know when I do a real test run.

Thanks for all the help, and thanks to Pelican Parts for the quicker-than-expected delivery of my replacement dipstick and books. Much obliged!

The results are in, sports fans. Chris Bennet gets a cigar for nailing the answer in the very first reply! I drove the car 90 miles today and the temperature needle never even got to half-way. Thanks to all for your your assistance, questions, and encouragement.

Now I have one more question to ask. How much damage did I do to my engine by starving it of oil in that way? :(

Probably none. If you are selective about the stuff you choose to worry about, then this is one of those things to set aside. Too much to choose from. I think you did no damage whatsoever.

The early-SC oil starvation problem folks mentioned here, happened to guys on the track. They don't seem to have damaged their engines. worry about something else. And don't jack on the plate. Jack on the rib that runs from the plate area to the fan pulley area.

I like to be selective of the stuff I worry about, and I would be very happy not to worry about having killed my Porsche's engine! Thanks for the encouraging words.

As for jacking up the car, I'll take your advice. Gracias!

Not to open a can of worms... After seeing how thin the case is in the sump plate area... I will never be jacking my track car from the motor (3.0 based). I will be adding the tow hook/jack plate....

Well in fairness to Porsche engineers, I think you have to attribute my sump plate damage to my carelessness about aligning the jack and not to the gauge of metal they used on the plate. I've jacked it up this way many times before and had never damaged anything -- I blame the cold, cold weather.

Down here in North Carolina, having to put the top on is a sign of a cruel winter! ;)

alls well that.......

that must be a relief.

personally i would avoid lifting in that manner - use the chasis. jmho.

I have not seen it, but a couple of folks have told me that the factory specifies you can jack on the rib I described. Some of those people are folks who have been dealing with Porsches for a VERY long time. I would agree that the case casting around the sump plate is thin, and I do not jack against that area. Not comfortable with that at all. But that rib is pretty substantial ("skookum" as we would say here in the PNW) and it's near the corner where it curves upward toward the pulley area. It's okay if someone wants to avoid jacking against that rib. But it's also okay if they do. Been done bazillions of times by lots of folks. The only potential problem is the smoothness of the rib. There is potential for the car to roll forward, allowing the jack to slide along the rib. So, use wood, and block the front tires.

Then, of course, place jackstands under the torsion tubes for safety.