Glassmuseum

I just completed a timing/balance belt job on my 944, along with replacing all rollers, seals, water pump, alternator and oil pump drive. Everything seemed to go well. I followed Clark’s garage processes and got everything back together and the engine seems to be running fine at first.

After a few moment, I noticed that the front crankshaft pulleys were wobbling and off balance. I also noticed a tapping sound after a few minutes that I initially thought was coming from the distributor but later found it to be coming from the cam cover area - closer to the front behind the distributor.

I have seen that sometimes that pulley can be installed out of whack so i decided to pull it and re-torque and make sure it was square. I pulled it off and here is what it looked like.



Deep grooves where it was installed incorrectly




I decided to clean it up reinstall thinking that it was me that installed incorrectly. I wants also this time to verify that it was square on the shaft. I got it on the shaft correctly. I know the wear is potentially part of the issue but I wanted to test since I could tell that the off square grooves were already there or done by me. Here is a pic on the crank before torquing:



Pulley on crankshaft before torquing bolt down

Unfortunately after install it still wobbled. I took some slow motion video.



I also noticed a light tapping sound which seems to be coming from the cam cover. Videos:



For context, here is everything I did during this job:

• timing and balance belts, rollers and tensioners
• oil pump drive and o ring
• main crankshaft seal and balance shaft seal and race
• water pump
• alternator
• new v belt

I have only ran the car for a total of 6-8 minutes since finishing. I have seen some past threads about how the pulleys contribute to driving the oil pump. So I am now concerned that the engine is not getting enough oil and that has led to the tapping sound and done some damage. TBH I am not sure if the oil gauge works and is accurate in the car but it seems to be correct upon cold start reading around 5. I haven’t let the car get fully up to temp yet to see what happens later.

Another thing: the alternator pulley doesn’t seem to align properly with the AC and crank pulley. Could this also be contributing to the wobble?

Does anyone have any suggestions on next steps?

1. should I source a new PS pulley and install? Any ideas on how to remedy the wobble if new pulley is not it? Should I also reinstall old alternator to see if that is contributing to the wobble?
2. Should I not be running the car at all right now?
3. Is the tapping potentially something that is being caused by oil not being distributed by the pump? How can I properly test that the oil pump is working?

any help and insight here is greatly appreciated. I have spent a lot of time and tried to follow procedures here so I am little stumped on next steps. Thank you.

Zirconocene

Looking at those pictures of the parts it seems to me like you really want to replace those pieces. It's hard for me to believe that those indentations (?) were put in by your work; they seem to be a bit older than that. Obviously, I don't really know.

I don't really have any advice to offer as I don't know the 8V engines particularly well. However, if you're looking for replacement parts that are not quite OEM, Lindsey Racing makes a nice, pretty set of pieces.

Good luck

walfreyydo

Is the crank pulley bent/warped? If you set it on a table or flat surface face down does it sit flush?

Honestly the wobble doesnt look horrible, obviously the PS pulley wobbles more and you may want to consider replacing that.

My guess is both of them may be slightly bent or warped. Make sure the crank bolt is torqued to 155 ft lbs, make sure you re-installed the crank pulley, timing gear, washer and oil pump drive gear correctly, if you had removed those.

Glassmuseum

thanks. So you think the alternator pulley as well? Seems less wobbly. Unfortunately I installed back in the car so I can’t check the flushness. I only inspected from the sides and the hole. But it did maybe seem a little oblong. I guess my main worry is that this is throwing off oil flow/pressure and pressure and leading to the tapping. So I’m a little concerned with even running it if the wobble is by itself okay..

Maybe tough to make out but here are pics from the side.


.

Glassmuseum

also yes. This was my first thought. Second guessing my install. I did replace the seal, oil pump drive gear. When I installed oil pump drive gear it fit in really snug but didn’t go all the way in flush against the seal. I pushed it in. Tried to turn it. It seemed seated. Every picture I found the lip seemed to be slightly sticking out and the old
one was well. I installed the metal washer behind that then the timing gear with the flange facing the front of the car (when I initially pulled the gear off the previous installer had the flange against the timing cover. Then the balance shaft gear>AC pulley>PS pulley.

wondering if I should pull the whole thing out belts and all and check. Does anyone have any pictures of how the pump drive>washer>timing gear spacing should look? I got the closest I could picture right now of how much spacing is between the seal and the timing gear. Tough to really tell but with the spacer it is a about 1/10 on an inch or so. Is this generally normal spacing?

austin944

If it's been weeks since the engine was run, you can have valve lifter noise that can sometimes take a while to fade away, like over 15 minutes.

Glassmuseum

Thanks. was just thinking about this. However it hasn’t been weeks since it has ran but I haven’t fully driven it from my driveway in weeks. I have started it a few times and let it run for a few mins over the past few weeks.. Pulled it into the garage last Thursday. ran it for maybe 7-8 mins.

I wanted to try and let it run for a bit but a little concerned since I’m not sure if my oil gauge is working correctly.

do you think it’s safe to try? i noticed my oil gauge was kind of fluttering but it calmed down so not sure if it is accurate. I was going to change the oil anyways soon so wondering if I should go ahead do that before letting it run for a bit.

Glassmuseum

Update: I felt brave and ran it up to temp and I have more faith in the oil pressure gauge now. It generally followed the same pattern from Clark’s garage write up. Started at 5 from cold start and progressed to somewhere around 2.5-3’ish. So I think that I am getting oil pressure.

the tap was also dissipating here and there. I had to really listen and try to pick it out. I used a large screwdriver as a makeshift stethoscope and i could hear some ruffling in the cam area but maybe more like general machine noise? I did make out the tap here and there though so I am going to keep an eye on it.

Zirconocene

Just to make sure, is the tapping you're hearing different than the injector clicking? It seems like what you're describing is a different sound but, if not, the injectors are noisy and that's pretty normal.

Cheers

Glassmuseum

no I believe it is coming from the cam cover. I am hearing the injectors as well. It was very faint last night and I did use a screwdriver as a stethoscope and pinpointed it. It is more of a tapping sound.. hoping that it is just a lifter that needs to settle?

walfreyydo

Rewatched your videos and I am fairly convinced that the wobble is mainly coming from the PS pump pulley, which looks bent off center in your photos. Based on your description it sounds like you reassembled everything correctly, and the fact you get good oil pressure supports that.

I would replace or just remove the PS pulley and see if the crank pulley wobble goes away because I think the PS pulley wobble is causing the crank pulley to wobble. I suspect if the PS pulley is removed, the crank pulley wobble will disappear. The good thing is those PS pulleys are really cheap:https://plyhammersparts.com/products...02d1422e&_ss=r

Glassmuseum

thank you very much. I sincerely hope you are correct. I am going to try and source one of these and start with that. Assuming this is something I won’t be able to get new.

Zirconocene

These are still available new. No affiliation, and you are always well served to shop around, but here is one particular example of a source for new parts, including this one: http://www.autoatlanta.com/porsche-p...section=102-00

It's part #24 in that diagram, Porsche PN 94410221403. If you don't have it, Porsche's PET is an invaluable resource.

Cheers