rlyon

I just got this porsche 944. the timing belt broke and the valves collided with the pistons. All the valves were bent horrendously and one broke. I have a new long block on its way. The 944 is an '84 car and the long block is an '87. Im just gonna swop out the motors, should the year difference be an issue? I dont have a manual yet (on the way), so i know thats the first step. What is involved with the engine removal? Is it a lot more challenging to remove it out the top? I have the head and the timing belt cover off. The starter is dangling. Any advice would be appreciated. Im only 14 and pretty new to working on cars (fixed up a Wrangler with the same problem resulting in two bent valves).

Thanks,
Ryley

The car has 49k miles and the long block has 87k. Is there any maintenance i should do on the long block before I put it in the car?

Songzzz

With the head already off, it will be easier to get it out from the top.

Campeck

wow...14!!
you should have been here earlier and gotten a free membership!
wow...he's def. the youngest here now. WELCOME!

Swagger93

Well, lets see, 87k.....

Do these things in respective order based on the amount of money you have.

Timing Belt
Balance Shaft Belt
Water Pump
Timing and balance Rollers

Timing belts are such a huge source of headaches on these cars, my saab has a chain with 207k on it with no problems, wish porsche would have been the wiser.

rlyon

It has a new belt. Yeah I can see the headache. That broken belt really damaged the motor.. It could be they used the belt system instead of a chain because the 944 is a high RPM motor. Also its a large 4cyl running at that speed so there's gonna be harmonics problems (that's why theres the balance shaft right?). The gear drives can amplify crank harmonics. Belt systems also provide less power loss through friction. It's also more tunable. Just to replace the chain on my jeep I had to remove the oil pan. Huge pain. Then I put it back to find out the oil pump is shot. Different story..

Anyway what's entailed in pulling the engine out the top? What else should I pull off?

I was thinking of picking and pulling the best parts off each motor. For example the new belt was on the bad motor (previous owner replaced it and began to pull off the head but found out it wouldnt turn over). The block on the trashed motor has less mileage and I think may be ok so I was considering putting the older pistons in that block, and what not. Should the year difference on the motors prevent that? The only difference I'm aware of is the self tensioner.

Danno

Check out Clark's Garage for step-by-step procedures for everything. Good luck! I'll buy that old engine from you if you don't have any plans for it.

rlyon

That may be a possibility.. I'm up in San Fransisco.

Anyhow just a pick. Set me back $1200

Dave

A chain wouldn't last 10 minutes in a 944, Porsche used a belt for a reason.
We have a fairly tall block made of aluminym alloy, it expands quite a bit as it heats up. The belt streches as the block expands, a chain would just snap. This is also the reason that the belt service interval is so short, all that streching shortens the lifespan of the belt.

Tom

What else got damaged? Wouldn't it be easier to repair/replace just the head? I believe there are didderences in the DME system (solvable by using the old FI parts?) and in the size/location of some of the sensors.

Ken D

The DME for the '87 will have different fuel maps. The '87 AFM also uses a different voltage signal. Find out more from FR Wilk, the DME expert.

www.frwilk.com

Peckster

Before you start talking about swapping motors, what shape is the new one in, is there any kind of guarantee on it, such as it's in good running condition or has good compression? Why not just switch heads? How badly are the pistons damaged?

M758

You can put a 87 motor in an 84 chassis.

I did this a few years back in to my race car.

I had an 87 924S parts car with solid low mileage motor and striaght chassied 84 944 with motor in need of rebuild.

I pulled the motor from 924S and installed in the 84. Fuel lines come in differently. and so you will need to either use the 84 fuel rail or do some fabbing to get the 87 one to fit. DME is different between 87 & 84, but the 84 stuff should work just fine on the 87 motor.

Not much is too hard to get around.

Also for reference.

After duty in my race car that 87 motor suffered a rod bearing failure and blew up the block. I went back to my 84 motor and rebuilt that block to accept the undamaged 87 head (Just need 1 valve). I mated the two together and ran 87 injection, 87 cam and 87 DME one it. Engine has run strong.

I never worried about emissions however since it is race car, but I would not expect it to be an issue.

M758

Yes.. best thing is new rod & main bearings, water pump, timming belt, front end seals and possibly a new clutch.

Much easier to do that suff with engine out. I did not do and thing, but belts when i put my 87 long block in my 84, but it had only 47k and had just had the water pump replaced.

SoCal Driver

Use everything for the injection from the 84 including the fuel rail. If you got the fuel rail for the later engine you can swap in the injectors (with new o-rings). As was mentioned the later 944's used a different hose routing.

The later engines have a two prong gauge temp sender. Use the larger of the two prongs for the single gauge wire.

Use the intake manifold from the 84 including the AFS. Also use the exhaust manifolds. While you have the intake off you need to use your early idle control valve. The later valves are controlled by the DME and will not work on the early electronics.

I would reseal everything that looked like it was leaking before putting the engine in including the flywheel seal.

Definately do the timing and balance belts and replace any roller that even hinted of being worn. If the water pump looks original replace that too.

Check your clutch disk. If it's a rubber center unit replace it with the spring center. Also replace the throw out bearing.

rlyon

This is the top of one of the pistons. They all look like this. Are they workable? Do you think the rods and crank are OK?

http://www.uploadyourimages.com/view...5pistontop.jpg