my DIY engine rebuild

[epapp]

How many miles are on your car? I checked your first post but didn't see. Everything is so clean on the engine so it can't have that many miles. It doesn't even look like it has the typical browning from heat cycles and age

[flaps10]

Might be a stupid question but about how much does the engine weigh?

Way too heavy to be mounted in the back of a sports car, I'll tell you that. It's a beast. Back in my young and stupid days I used to drop a type 1 VW engine, strip the heater boxes off and carry it in the house. I recall reading that the VW engine would be in the neighborhood of 185 pounds in that trim but I never had one on a scale.

The M96? No idea, but I'm much older, a little bit smarter now and sporting a ruptured disc from about four years ago. I could tell just sliding it out on my makeshift pizza board that there would be a lot of stuff removed, and an assistant before it was going to move to my bench.

Originally Posted by epapp

How many miles are on your car? I checked your first post but didn't see. Everything is so clean on the engine so it can't have that many miles. It doesn't even look like it has the typical browning from heat cycles and age

My car just turned 120K miles. I agree the engine is way too clean. It would appear that it had a cylinder head recently. The valve covers are both marked and the oil scavenge pumps in the heads are also marked so it may have been torn down even more.

This car was what guys older and more southern than me might refer to as a "pig in a poke". I don't know the history of the car and I didn't get a PPI. That of course goes in the face of everything you read about buying a Porsche. You're supposed to walk away from cars like mine. And if you pay someone to work on your 'exotic' car then that's no doubt a smart recommendation.

However I also got my car for about 2/3 of the going rate for an S model, and I also bought the car as a hobby. Maybe I'm an odd one, but I bought a Porsche so I could enjoy ownership, including working on it. I don't enjoy writing big checks as much as some people I guess. In the end if I have to put $5k in parts and machine shop work then I'm still at a break even, and I'll have a car I know I can trust.

Enough blathering.

This morning it was time to clear the decks. I started by clearing my work bench because I hope to have the crank case sitting on it prior to tearing it apart.


Yet another lousy phone pic. You'd think Katherine Hepburn took these. Anyway this is part way through "making a hole".

And then it was time to clear the top and bottom of the engine of anything that moves.


Top side clear. The starter, oil cooler, alternator and crankcase breather apparatus all come off easily. The power steering pump though - what a scream. It's mounted to a pedestal which you would really like to remove in one piece and take the power steering pump still attached to it. But there is one base bolt that is pinned down by a lug on the power steering pump. You can't just remove the power steering pump because first you have to remove the pump pulley and then you'll discover that one of the hard lines is in the way. It's like one of those puzzles with one missing square. I found I could leave the hard line attached and remove the pulley and the four bolts (three from the front and one from behind) that hold the PS pump to the pedestal. By doing that you could get just enough room to sneak a box wrench in and inch the remaining base bolt out. Tedious but it gets you there.

Then you're looking at a pile like this:


Next I carefully tipped the engine up on end and removed the exhaust manifolds. Pretty easy with the help of an air impact wrench. It managed to come up with quite a puddle of oil and coolant it was hiding while I did the work. Then back down to a stable position.


Before anyone asks, the hideous black area on the board is from being used to host some things I spray painted for my woman recently. So far (other than the oil filter and the IMS bearing/shaft) I have only seen clean oil and clean coolant.

[kodabear]

Originally Posted by flaps10

Way too heavy to be mounted in the back of a sports car, I'll tell you that. It's a beast. Back in my young and stupid days I used to drop a type 1 VW engine, strip the heater boxes off and carry it in the house. I recall reading that the VW engine would be in the neighborhood of 185 pounds in that trim but I never had one on a scale.
.

Too heavy to be in a sports car? You might want to educate yourself a bit on engine weights before making such a statement. The m96 weighs significantly less than the old air cooled 911 motors. And comparing it to a type I vw...really? The m96S makes 5 times the horsepower lol. FYI The 3.5 liter cosworth dfv f1 engine only weighs ~30 pounds less than a m96 even with m96 heavy street flywheel. The dfv was not too heavy for Jim Clark.

[flaps10]

I was mostly poking fun at rear engine cars as opposed to mid engine cars not trying to roast the M96 as an oversize boat anchor. I'll try to stay on topic.

[rp17]

Originally Posted by flaps10

I was mostly poking fun at rear engine cars as opposed to mid engine cars not trying to roast the M96 as an oversize boat anchor. I'll try to stay on topic.

Humor is good. Thanks for the pointers so far. Damnit need more popcorn.

[kjc2050]

Originally Posted by flaps10

I was mostly poking fun at rear engine cars as opposed to mid engine cars not trying to roast the M96 as an oversize boat anchor. I'll try to stay on topic.

I took it as humorous. Great thread; keep it up.

[Chuck W.]

Originally Posted by kjc2050

I took it as humorous. Great thread; keep it up.

Same here. Love this thread.

[flaps10]

After posting up yesterday I really thought I was going out to the garage to look at some camshafts. I should have known better though, since I've read about the use of some of the special Porsche tools required to properly remove the camshaft cover and remove the cam shafts.

Put simply, if you just remove the camshaft cover the cams will want to fall out and surely they'll get all gouged up in the process. So, tool # 9634 to the rescue.

Now I noticed on 986fix.com and also "project nutrod" that the guys who were kind enough to post up their pictures made their own special tools. So it seemed fitting that I would do the same. Time to go ponder the requirements.

Tool 9634 uses the same lug used to hold the LN engineering cam locking tool, only instead of engaging the key way there are two cylindrical features which lock in the centers of the cam shafts. Time to measure the distance between cam shafts. Now I noticed that on the two web pages referenced that they show the steps they used to create their tooling but don't mention the dimensions. It can't possibly be proprietary since anyone could measure the distance on their own.

Now maybe it's not kosher to publish the dimension so I won't, but it rhymes with 112.5mm. As for the diameter of the cylindrical features, you just need to dig out the socket head cap screws that used to hold your clutch pressure plate to your flywheel. They fit perfectly in the ends of the cams.



Going with that I imagined some tool made from a simple piece of angle. Two tapped holes 112.5mm apart and the clutch bolts threaded in. Then it would need a hole on the other leg of the angle, centered. The biggest hurdle would be getting a face of my new tool to line up exactly with the centerline of the two cam bolts.

I made a shopping trip with my sketch to the local home box store. I came up with a piece of L angle aluminum and after that I needed a spacer. The cheapest spacer I could come up with was a nut that was a slip fit for the M8x1.25 bolt (aka clutch pressure plate bolt) that would hold the tool to the head.

Next it was off to my son's house to commandeer the drill press I left with him. Getting the two cam bolts to line up on the same center as the inside face of my new "spacer" would be easier done than said. Behold:



I needed a rigid way of starting the two threaded holes if I had any chance of nailing my 112.5mm goal. I chucked up a stiff drill bit which I'm going to erroneously refer to as a center drill (it's a countersink tool in real life, but the closest they had at Lowe's). Bottom line, it wasn't going to wander when starting a hole.

Chucking it up in the drill press I brought it down and rotated my table until the rear (non moving jaw) of my vise was right on the money for the tip of the "center" drill. Then I put my angle in, with the spacer (aka M10 nut) faced towards the back jaw. I could then start a hole any damn where I pleased, and then slide the work piece along the vice jaw exactly 112.5mm.

I did that by bringing my center drill down and just marking off the drill point for the future hole. Then I scribed an arc at 112.5mm. All I would have to do is loosen the vise and slide the part down until the tip of the center drill intersected with my arc.

I'm skipping a couple of steps here but this is another look



As you can see, the face of my spacer being pushed up against the rear jaw of the vise assures the holes will be exactly lined up with the lug on the cylinder head.