rlich8

She was running beautifully and then, well, you know. Pulled off the air cleaner pipe and gone. Do I need a motor? Or no? I've found posts that say a 16v S RoW is not interference. I've also looked on the Gates site and it says yes it is interference. Thanks in advance.

DougM

My '84 Euro S was not or else I got very lucky. Snapped the belt while accelerating hard with no damage.

rlich8

I was at a stop light. Not at speed just idle.

I'll be doing a compression test sometime this week.

With a little luck they'll be within a few percent of each other and I'll just need a belt and will likely do the water pump as well.

James Bailey

I firmly believe it is NOT.....I also KNOW many customers have been charged for a valve job by shops more familiar with the 944...Cause guess what if the shop pulls the heads no way are they going to go OOPS guess what no bent valves Sorry ...there is more question about the late style higher compression being interference BUT the workshop manual first discusses setting the crank at 45 degrees off TDC for the 1985 model 32 valve which FOR SURE is interference Not that that stopped the L A dealer from charging a customer to put a belt on one JUST to SEE so $1,000 later, Yup bent valves now we have to pull the engine...

rlich8

Not too worried. In fact, it commits me to the car if anything. Last week I was pulling my hair out with the thing trying to find a proper exhaust system, I half thought of selling it. Drove an hour today and remembered why I love this thing so much.

Back to business -- in my reading it seems as if despite the higher compression in the RoW 4.7 motor, that I may get lucky.

James Bailey

Correct your early Euro 4.7 S should be fine....

rlich8

I'm almost happy in a way. Now I can do the crank seal, cam seals, etc.

Now. Question is. PorKensioner or no?

James Bailey

The stock tensioners never really fail they just often got blamed for a failure.....many shops think they are oil pressure fed from the block

rlich8

I'll wait for some more opinions on that then.

hacker-pschorr

Interference by design or not you won't know until you put a belt on and do a compression test.

Carbon buildup can close the gap enough to wreck a valve.

My 944S has closer tolerances with valve to pistons than a 32V 928 yet when my cam chain snapped no valves were bent. Got lucky there but both came were destroyed.

You need to determine why it broke. Really really old belt, water pump or roller locked up, debris in the belt etc...

Even if valves are bent, you don't necessarily need a whole new engine.


That's even funnier when you consider the 944 Turbo is not an interference engine.

I think most shops simply assume broken belt = bent valves.

Hilton

Nothing to add on the interference that hasn't been said.

However, when you get the front of the engine off, have a good close look at the camshafts - one of them is prone to breaking where the cam gear is mounted and a the belt is over-tensioned. I think the left-side cam from memory.

Also have a good close look at the oil and water pumps.

Its possible your belt was just so old/hardened/cracked that it broke, but more likely that something was the reason for it to break. Especially as the usual failure for an old belt is to shear the teeth off, not to break.

rlich8

Interference by design and the possibility of carbon build up damaging a valve makes sense with everything that I've been reading on other boards and resources, as well.

It looks like my exhaust system will be taking the back-seat, for now at least. My experience with other vehicles has me checking water pumps and oil pumps when working on them any appreciable amount. I had a 1963 MGB that I pulled the motor out of to paint and detail and freshen it up. We decided to replace the oil pan gasket and figured may as well check the oil pump. So we did. Well, the circular housing literally broke apart in my hands. Who knows how many tens of thousands of miles it worked with that stress fracture. And it had good oil pressure!

Anyways, back on topic. Yes, it definitely snapped. I'm putting my money on the tensioner or the water pump being bad.

Most shops do assume bent valves. My tenant is an Audi mechanic, worked a dealer for about five years. Smart guy, and when I called him up he said "sounds like you need an engine" and I said "not necessarily."

Thanks, guys!

Hilton

Just to clarify, your engine is not interference by design.

The first interference 16V engine is the "Euro" 4.7L with LH2.2 fuel injection, using the high compression pistons introduced partway through the '84 model year (early '84 "Euro" are non-interference too).

Of course, a lot can have happened to the engine in the intervening 30 years - carbon build-up, heads possibly off the engine (and resurfaced/shaved), fitted with later pistons by a performance nut etc. So forensics are your friend.

First job is to take the front covers off, check everything, string a belt, and do a leakdown test.

rlich8

I know, I should have said "versus"

rlich8

Who sells the best kit to purchase for this job?