CamShaft Timing
 

Afternoon Guys

So after fixing the AOS we got a knock in Bank 1.

I got a Durametric and help from Marcus it says
Porsche fault code 322 - Camshaft position with respect to crankshaft bank 1.

I pulled the 2 green plugs on the front of the car.
Set the crank to TDC - Intake and then Exhaust.

In both cases the notches on both cams in TDC are at the 1 & 7 o'clock position.
(While rotating the cam the notches on both cams do line up at one point prior to the crank getting to TDC.)
It seams like that what ever went wrong happened to both cams equally?

Could the solenoid do this or do we think its a bigger problem?

Do I need to run the car with the durametric attached to se how retarded? or can we determine that there is a problem and I need to proceed with repairs?
(I'm afraid to run it and cause damage)

I've read that a few things can cause this?

Can these repairs be done by an average guy or do I have to take to a shop?

I read some where that valve train repairs can be done while it's in the car?
(Is this true? Hope So)

Please chime in...

Cheers!
Bart

Here is the position of the top cam at TDC.





http://986forum.com/forums/uploads02...1474650212.jpg

Before you do anything else., pull the crank locking pin and rotate the engine another 365 degrees to make sure you are really at TDC. It is common for those playing with the cams to not realize that the cams turn at 1/2 of the cranks rotations, and find the cam notch off. We see this all the time on DIY IMS retrofits when they cannot get the cam locking tools in because they are not at real TDC.

I have ZERO hands on experience with the internals of these engines. Save oil change, belts, filters, etc.

Having duly qualified myself. If the engine is at TDC and your cams are that far off on both sides, then I suggest that a chain has slipped. I wouldn't turn it over anymore until you verify the cause. If you have a bore scope, pull the plugs and look into each cylinder and see if there is any damage on the tops of the pistons. Harbor Freight has them for a reasonable price. Ryobi has one at Home Depot that is quite nice.

The notch on the bottom of the cam looks like it has a burr in it? Damaged?

Best of luck.

Hello Bart,

i did also say compare the camshafts of bank 1 and bank 2. ;)

JFP is absolutely right about TDC. Very good advice.

Regards, Markus

How do you do that?

Hello Bart,

Set engine to TDC. Note what JFP said and rotate again 360 degrees and check if there is any change on bank 1.

Take out the 2 green plugs for the 2 camshafts on bank 2 too. Check if there is a difference of the cam position in relation to bank 1 and tell us what you've found.

Don't start the engine without these green plugs. ;) You'll need new ones before you start the engine.

Regards, Markus

And be sure to only rotate the engine clockwise.

OK here is what we have found/determined

1. Bank 2 is in time
2. the 2 cams on bank 1 appear to be in time with each other but not with the cam.
3. we scoped the pistons and there is no sign of contact (damage)
4. we could not see the cylinders

It almost appears that bank 1 skipped a tooth on the main timing chain if that is possible?

What do you suggest out next step to be?

Thanks again for all the help



We think it might be that the

Hello Bart,

OK – seems we have a real problem.

What could have caused that:
- hydrolock cause by AOS failure
- failing IMSB
- bad chain tensioner
- bad chain rail

What to do next:
You can move the chain while lowering the engine and removing the the head cover. But there is not much room. Also you have to find the cause why the chain skipped over one teeth. And you have to check if anything else is damaged – valves, valve seats, hydraulic lifters…

So you have to pull the engine, fix camshafts, crankshaft, remove the cylinder read of bank 1, check chain tensioners, valves, hydraulic lifters, chain tensioners, IMSB…

To to this you'll need special tools and / or the skills and tools to build them. I also would recommend a lift.

Also you have to think about how to pull the engine. Fastest way is to pull the complete drivetrain including engine, transmission, axles, struts, exhaust system in one piece. But that is not possible in a workshop without lift, good tools…

Slowest way is to remove everything piece by piece. That is doable in a home garage, but takes time.

I don't know you skills and tools. Also i don't know if you have the time, space, skills, tools… to do that. It's not rocket science but it will take time and money.

If you want to do it yourself i would recommend to buy a good workshop manual and read what things are have to be done. There are also videos on youtube, but these don't show everything. There are people on this forum that might help you when you stuck.

If you read everything, know what tools you need, know what has to be done, know what additional work has to be done (for example bleeding the cooling system), know what maintenance work can be done if the engine is out of the car, know what tools you will need – than you should start. Not before. ;)

Else bring it to am experienced Porsche shop. But it will cost some money. I would recommend to ask for a cost estimate to diagnose. Will be hard to get a cost estimate for the final repair, as we don't know what failed and what is damaged.

Maybe some guys in your region can help you. I saw you might attend a meeting. Maybe good idea to talk to other Porsche owners in person and discuss what to do.

Don't turn on the engine. ;)

Regards from Germany
Markus

Properly resetting the cam timing is a time consuming, but not difficult process once the fault that caused them to jump time is found and repaired. It also requires some specialized tooling and specific knowledge. If memory serves , the service manual procedure for resetting the cam timing runs some 14 pages.

Hi Guys

I hope you guys have the answers to these questions.

How long would it take a shop to do this work?
(I'm just looking for time values)

1. Remove and replace the engine.
2. How long does it take to re set cam timing.
3. Replace bad tensioner
4. bad chain rail
5. Anything that we may have missed


We are just trying to get a handle on some time lines.

Thanks Again
Bart

1. Couple of hours each way.
2.Again, a couple of hours once the other repairs are done.
3. Half an hour.
4. A full day (it is all the other stuff added together, plus the labor for the rail itself)

All good advice but, what I don't uderstand is how did you get here from repairing an AOS? A seeming non-sequitur.

I wish I could tell you..

We changed the AOS.
Let it warm up for approx. 15 min and the smoke was almost all gone.
Took it for a test drive, approx. 3 kilometers and now we have this...

I don't think they are related? Just bad luck/timing.

I'm open to suggestions.