Swapping engines

[elgyqc]

Originally Posted by LoneWolfGal

I couldn't stop fiddling with the cams while waiting for the replacement compression tool to arrive, and I was struck by a Grant Hargraveish idea...

LOL
Not original though, I think this is suggested in the Pelican instructions.

Originally Posted by LoneWolfGal

Only one hitch, and I'm not sure it's a problem. I carefully kept the lighter-color chain links mated to the divots in the sprockets so that the cams would be in time with each other. I wanted to keep them both at 12 o'clock (while they were on the table). However, during the manipulation necessary to get the chain in place over the pads the cams rotated a teeny bit, to 1 o'clock, enough so the intake cam's link and divot are slightly apart, even though they're still lined up (see photo 2). I should have checked that before I snipped the pull-tie, because the cams can't be rotated without compressing the pads again. My question is, is it necessary to correct the problem so that both cams' links and divots are at 12 o'clock before they're installed in the head? Or can the cams be rotated slightly by hand after they're installed, with the cam tool inserted into the ends of the cams, the cam retainer loosely bolted in place, and before the double chain's sprocket is bolted to the exhaust cam?

I don't have a spare engine at the moment (just sold it) so I am trying to visualise this. My understanding is the following...
WIth the crank at TDC for the cylinder bank in question and the slot in the end of the exhaust cam parallel with the valve cover mating surface (and/or - the cam tool installed in the ends of the cams) that cam is properly positioned. Positioning the second cam is a product of the number of chain links between the divots as you call them. You can simply count the links... or use the coloured links... or both. If I remember correctly with the compression bolt in place you can even reposition the cam sprockets vis-a-vis one another. You can move the cams once they are installed in the head before installing the cam tool and attaching the sprocket for the timing chain. With the cam tool installed in the ends of the cams nothing will move, but the divot for the exhaust cam is by definition in the right place. With the divots properly placed the slot in the end of the intake cam should be properly aligned also.
Hope this is clearer for the reader than it is for the writer.

[LoneWolfGal]

Thanks, Grant. This is an esoteric process and difficult to describe clearly. By "cam tool," I was referring to the tool on the right, which fits into the ends of the cams without locking their rotation but prevents them from falling out. By "cam retainer," I meant the tool on the left, which also keeps the cams from falling out. The lighter-color links are seven links apart and were paired with the divots on the sprockets. So even if the cams rotated a bit during the process of fitting the chain over the pads, it would only matter if the chain jumped a tooth and a lighter link was no longer lined up with its divot. Also, it's my understanding that, once they're loosely held in place by these tools, the cams can be rotated by hand if necessary to line up the slot.

[LoneWolfGal]

I picked up some of this stuff, on JFP's recommendation: "ARP 100-9909 Ultra Torque Assembly Lubricant - 1.69 oz. Fluid Squeeze Tube." $13.99 at Amazon. I will of course use it on the compression tool, but it seems to me most fasteners used in the engine would benefit from it. What about flywheel and pressure plate* bolts? Cam cover and sump cover? Cam caps?



*By the way, I've decided to replace the pressure plate along with the clutch disc and throwout bearing. I had intended to replace only the disc and bearing, but I've come around to the idea that I'd be crazy not to put in a new pressure plate while I'm at it.

[piper6909]

Originally Posted by LoneWolfGal

I picked up some of this stuff, on JFP's recommendation: "ARP 100-9909 Ultra Torque Assembly Lubricant - 1.69 oz. Fluid Squeeze Tube." $13.99 at Amazon. I will of course use it on the compression tool, but it seems to me most fasteners used in the engine would benefit from it. What about flywheel and pressure plate* bolts? Cam cover and sump cover? Cam caps?



*By the way, I've decided to replace the pressure plate along with the clutch disc and throwout bearing. I had intended to replace only the disc and bearing, but I've come around to the idea that I'd be crazy not to put in a new pressure plate while I'm at it.

Definitely not the pressure plate and flywheel bolts. If it's like most other cars, you'll want loctite or some other thread locker for those bolts. Assembly lube would have the opposite effect.

[JFP in PA]

Originally Posted by piper6909

Definitely not the pressure plate and flywheel bolts. If it's like most other cars, you'll want loctite or some other thread locker for those bolts. Assembly lube would have the opposite effect.

Almost, but not quite. You definitely want a dot of blue Loctite on the threads of both the pressure plate and flywheel bolts, but a coating of this product underneath the heads of the flywheel bolts makes cranking them to their final +90 degrees after torquing one heck of a lot easier.....

[piper6909]

Originally Posted by JFP in PA

Almost, but not quite. You definitely want a dot of blue Loctite on the threads of both the pressure plate and flywheel bolts, but a coating of this product underneath the heads of the flywheel bolts makes cranking them to their final +90 degrees after torquing one heck of a lot easier.....

True, but it seems she was talking about lubing the bolts the same way she would lube the compression tool, given she said she bought the product you suggested to lube the threads of the tool, as you suggested.

Now, putting a dab of assembly lube on the inside head of the bolt where it contacts the flywheel and the pressure plate,is definitely a good idea for proper torqueing. But you certainly do not want that on the threads.

[JFP in PA]

Originally Posted by piper6909

True, but it seems she was talking about lubing the bolts the same way she would lube the compression tool, given she said she bought the product you suggested to lube the threads of the tool, as you suggested.

Now, putting a dab of assembly lube on the inside head of the bolt where it contacts the flywheel and the pressure plate,is definitely a good idea for proper torqueing. But you certainly do not want that on the threads.

The ARP lube is used on a wide variety of fasteners, like head bolts/studs, crank carrier bolts, etc. to get optimum torque readings and clamping loads. If you go to the ARP website, they have a very interesting "white paper" comparing clamping loads, and actual vs indicated torque readings both with and without the use of fastener lubricants.

[LoneWolfGal]

Originally Posted by JFP in PA

Almost, but not quite. You definitely want a dot of blue Loctite on the threads of both the pressure plate and flywheel bolts, but a coating of this product underneath the heads of the flywheel bolts makes cranking them to their final +90 degrees after torquing one heck of a lot easier.....

Makes sense.

Also, you've convinced me that, after sparing no expense on the IMS bearing, I'd be nuts not to cough up a couple hundred more for factory clutch parts. I keep imagining the clutch giving out on some godforsaken stretch of road and wishing I had.

[JFP in PA]

Originally Posted by LoneWolfGal

Makes sense.

Also, you've convinced me that, after sparing no expense on the IMS bearing, I'd be nuts not to cough up a couple hundred more for factory clutch parts. I keep imagining the clutch giving out on some godforsaken stretch of road and wishing I had.

I always encourage people to never "cheap out" on projects like this as the labor involved in going back in to undo the corner cutting is worth more than you actually saved in the first place. And to those who would respond, "I'll be doing it myself so there is no labor cost....", yes, there is is what acountants would call "opportunity costs", the value of what you would be doing otherwise if you weren't back under the car again. Do it right, do it once......

[LoneWolfGal]

Originally Posted by piper6909

Definitely not the pressure plate and flywheel bolts. If it's like most other cars, you'll want loctite or some other thread locker for those bolts. Assembly lube would have the opposite effect.

Thanks, Al. I've used Loctite on conventional engines' flywheels and pressure plates, but I've learned not to make assumptions when it comes to Porsche's flat six, so I included them in the list. You and others on the forum are an indispensable source of knowledge about this engine. Thanks to your kind assistance, I will definitely have the best 986 in the poorhouse!