Cam timing?

[crashmy911]

Can cams be timed without taking engine out?

[kwikt 911]

Yep.

[Flat6pac]

But it generally isnt worth the extra work and the effort. Put it on the table.
Bruce

[yelcab1]

Yes, I have done it with an 80SC

[dtw]

Done it, but found it to be a huge pain and wouldn't ever do it again.

[otto_kretschmer]

I've done it and it wasn't that hard.

jack the rear up and take the muffler out and the back cooling tin

take out the spark plugs and check the valve gaps before you do it

then you need the right tools:

crows foot
z bar
two 1/2" breakerbars
cam holder socket
dial indicator
torque wrench

be patient

[kwikt 911]

I didn't find it that hard either.

[BILLS 84 CARRERA]

Mabie im a bozo,but i didn't find it that easy either. Every time i went to tighten cam nut the gauge would move past my desired setting, so i had to calculate how far it would move(set before mark) so when i tightend nut the desired mark would be acheived!!!! Any thoughts, or tricks w/ techneke? And what is a good dialindicator to have? Thanks you camtiming pros!!!!!!!

[JFairman]

I found it easy to do with motor in the car. To me it would be a ton more work to remove the motor and transaxle to do that. I also don't have an engine stand or place to put one if I did.

With the back of car up on jackstands and bumper and rear engine mount removed lower back of motor down 6-8 inches on to a jackstand. Then remove the chain case covers and just do it.
I replaced both 964 cams, all the rocker arms and shafts, left and right chains (master link type), cam sprockets, idler sprockets and shafts at the same time.

I was able to comfortably sit crosslegged on the ground behind the car while doing it in my driveway and everything was at the right hight right in front of me. I lay on my side on the ground while changing and adjusting exhaust valve rocker arms. That doesn't bother me much.

Only time I had to stand up was when using the special tool inserted into the cam sprocket holes to keep it from turning with my right hand while I pulled a click type torque wrench with my left hand to tighten the bolt. I was standing next to the right rear tail light while doing that.
Mine is an '87 turbo with the bolt that holds the cam sprocket on.

I snugged down the two bolts a bunch of times and rechecked cam timing on both cams until I had them as close as I could get them. Then I torqued the two oiled bolts and checked timing again.
That little pin that inserts into a hole in the cam sprcoket is not a precision fit and cam timing can be moved for and aft a little while it's in a hole before you tighten the bolt (or big nut on older motors) so you have to fiddle with it and repeat until you get it where you want it.

Just takes patience and it's fun and satisfying on your own car as long as you have the time and a comfortable place to do it.
I did all that around 6 years ago and it's run perfect ever since.

[JFairman]

I found a few pics I took while doing the cam replacements and cam timing with the motor in the car back in 2008.
You can see the blue hylomar I spread on the new chain case gaskets and they have never leaked or sweat any oil.
I also replaced all the plastic chain rails.

I did the cam timing with only the oil fed tensioners installed. Thats whats in there with the motor running so why not, and it's the spring inside the tensioner that tensions the chain and engine oil pressure only dampens it like a shock absorber.

Wadded up paper towels around the bottom side of the chain keeps anything like the cam timing pin from possibly falling into the case while doing this but the chain still slips through while turning over the motor.

[johnman001]

For what its worth, (and you already got excellent advice), I prefer to time cams with the engine out. I like to get them set as close to the same as possible (which means multiple iterations). I have set them once in the car, but it isn't as easy as there isn't much room to install the dial gauge on a valve.

Why do you need to set cam timing? I only ask as I have only needed to set timing if I disturbed the chain housings or replaced chains/ramps or other parts that I would typically drop the engine for in the first place.

I once had to do this in the car immediately after installation due to a leaky chain housing gasket/o-ring. Instead of pulling the engine back out (draining oil/pulling CV's, unplugging electrical), I just removed the muffler, removed the offending chain housing, sealed it back up and checked timing. I cheated and used my notes to check what the other side had been set to and matched that.

I wish you the best of luck.

John

[cmcfaul]

Either way cam timing is a pain in the butt. The crows foot thing always slips while trying to get 90 lb's of torque on it and keeping the gage exactly set.

[JFairman]

I'm glad my '87 uses the regular 6 point bolt and big washer to fasten the cam sprockets to the cams.
That fine point crows foot wrench for the big cam nut on the early motors looks like it could slip off like you said if it wasn't held in place on the nut just right.. and it's expensive.

On the 930 the bottom two and top left motor mount bracket fasteners are bolts instead of studs like regular 911's so the turbo support bracket is easier to remove and replace when changing turbo's.

When I got my car the bottom two bolt threads in the case for the motor mount bracket were stripped. I installed time serts in the case for all 3 of them to make them stronger than new. I consider that an upgrade for a 930.
You can see the time serts in my top picture above.

[mdripley]

Thanks JFairman your detailed and illustrated explanations are always extremely helpful to those of us myself included with less experience on these great cars,

[Smoove1010]

Originally Posted by crashmy911

Can cams be timed without taking engine out?

Out of curiosity - why would you want to? Do you suspect that the timing is off, perhaps due to chain or sprocket wear?

Having a grand total of one engine drop to my experience, I think I'd go for the drop, and adjust the valves while I had the easy access. It might be a wash as far as time invested, but jobs like this that demand some precision can be done to a greater degree of accuracy when access is good.

I understand not wanting to head down the "slope" though...