1989 930 5 speed top end refesh......?

[9hellheaven]

Well my 930 has covered a jaw dropping 70k miles now and i am thinking about taking a look to see what the health of the motor is like as a winter project. Anyone done any strip downs and found anything of interest at similar miles?

It's a car i will keep, and having done everything under the car in my 3 years of ownership, i would maybe like to start with a nice fresh motor to bring everything upto date. My plan is to keep it totally standard, but to give it a fresh start through prevention/ mechanical/visual improvement's that i hope will last the next 20 years.

Any thoughts or experiences please?

[Von Twinzig]

When's it booked in?

[9hellheaven]

When's it booked in?

 

pmsl!!!

 

Yes i am a bit like that am i not? .......Fact is though i like to improve and see things as they once were. Plus being an old fart now who has few pleasures why not?................................................................................

...................................................................... end of the month!

[flatsix777]

As a comparator, my 930 has virtually the same mileage, has good leak-down levels, good compression and makes all it's power. Clearly it will have wear and will perhaps need a rebuild in the next 30k but this could be 6 or so years of use for me. It may fail well before this for some other reason but that's a risk that exists with a newly rebuilt motor as well. Your motor is quite possibly the same or better, only a few tests will confirm. I appreciate that you may have decided to do this for condition which I can understand.

 

Cheers

David

[EDSSE]

Steve you obviously have too much bloody time on your hands mate.

You could do mine aswell.

51k miles though, not running briliantly though, i reckon its running very rich, (stinks/smokes when been sat all week)

[9hellheaven]

Well 930 has gone in today for strip down. I'm happy to post some photos and a brief report if anyone is interested as things unfold. I hope it's just a run of the mill refresh, and some visual improvements. Fingers crossed!

[Nige]

Yup photos are always good. Try and get some totty in shot too, always adds a bit extra spice.

[9hellheaven]

Well things are well underway with the engine top end rebuild. Any slight doubts i had about giving the engine a refresh have been well and truly removed by what has been discovered during the strip down process. It has to be said that the engine still ran very sweetly indeed, although certain issues became obvious the moment the car was on the ramp prior to the engine being removed, This was the first time it had been up for inspection since the last service around 12 months ago. One or two minor oil leaks that were of no real concern yet, however cylinder 6 had a pretty bad leak barrel to case which was evident by lots of burnt oil on the heat exchanger. Cylinder 2 had also developed a fairly bad leak but this time head to cam carrier. When the heads were removed one bank of cylinders/heads/barrels to case were showing signs of shuffle which meant that things were going to get a whole lot worse if i had'nt taken steps sooner rather than later. Ive also replaced the studs with Delaver as the originals had corrosion marks showing. The conrod bearings had some ware, and were replaced for peace of mind while it was possible to do so. Three cylinders were also showing signs that oil (still evident) was getting into the combustion chambers, this proved to be worn oil rings/compression rings and of course the possibility the barrels had gone oval. This proved not to be the case thank goodness and the barrels/pistons were in excellent order. The most startling find was the fact that the exhaust guides were just about as thin as they could get, it was possible to break them with finger pressure at the top edges. Sadly i didnt have my camera that day and they went straight to the machine shop to be replaced so i did'nt get any photo's, they were very very thin and on the verge of total failure with the bits causing goodness knows what damage to the top end. Three or four rockers were showing signs of the case hardning breaking up, again lucky no damage to the actual cams they were fine. Front and rear seals were weeping, they will be replaced. The thick rubber seals on the turbo to exhaust were in two parts so not offering any seal to speak of. I am also replacing the cross over pipe and the section which holds the waste gate due to heay corrosion being the original items. I am sure other stuff will come to mind and i will post some photo's if anyone is interested in seeing them later. rear tinware was rotten and could not be saved, it had been botch repaired at an earlier date, so a new one ordered. All other tinware off to the powder coaters. We have established that this is the first time the engine has been stripped since the factory in 1989, and 70,750 miles!

[Jim Rummy]

Fascinating stuff! I'm about to (pay) to have this done on my 88k mile 88 930 - god knows what will be found!

[9hellheaven]

Here's some photo's of my 930 rebuild. I really wish i had taken the camera to photo the exhaust valves they were so thin it was staggering. But anyway here's a few shots Starting with the block still with the old rusty studs in place.

 

 

oil stained heat exchanger from cylinder leaks on both sides.

 

 

here are the pistons as they came out of the engine, some wet with oil if you look carefully.

 

 

Rear most tin ware, totaly shot and badly repaired with filler etc. Would have been worth saving at 300 quid for a new one but sadly it was past it.

 

 

New exhaust section as original was dead at the flanges, not bad service though at 21 years old!

 

more to follow..........stop me if i'm boring anyone, i know its all been done before this top end stuff!

[9hellheaven]

This can't have helped the turbo make max boost can it?

 

 

Cylinders waiting to go off to the machine shop to catch up with the heads, with all the oil on the pistons i was thinking these may have turned egg shaped, but both them and the pistons had very little ware at all...amazing really. The rings both oil and compression were 70 percent worn, hence the oil issue.

 

 

It's possible to get a better idea of the rust on the original studs in this photo

 

Big end bearing with some minor scratches, all replaced with new shells etc to be safe.

[The Preacher]

This can't have helped the turbo make max boost can it?

 

 

It probably still reached max boost, but would have taken longer to get there!

[Dr Rock]

more to follow..........stop me if i'm boring anyone, i know its all been done before this top end stuff!

Bored? Us lot? Here, on this forum?

 

Anybody care to own up to being bored...?

[9hellheaven]

Bored? Us lot? Here, on this forum?

 

Anybody care to own up to being bored...?

 

Cool i'll just bang em on til someone says stop then! :mad jg:

[Dr Rock]

Cool i'll just bang em on til someone says stop then! :mad jg:

Good lad - normal service is resumed

[9hellheaven]

when cleaned these proved to be brand new. I recall it was mentioned they were replaced just before i bought the car in 2007.

 

 

Cam's were lovely, should have taken pic of rockers that were starting to give up on the faces, they will be replaced with new ones and all the ajusters also. No doubt cams were saved by picking up the rockers faults early.

 

Con rods coming off for shell replacement and checking.

 

 

Con rods all good.

 

 

New Delaver studs now fitted for another 20 years...........i hope!

[9hellheaven]

Pistons all cleaned and ready for refitting...lovely things!

 

 

New rings standing by for fitment.

 

 

Number one piston back in its home for many a year.

 

 

A lovely photo of things starting to make real progress now, it's a shame to cover them up is it not.

 

I will add some more as things develope, thats more or less upto date. We now have to wait for the tinware to return from the powder coaters before the heads can go on.

[Jim Rummy]

beautiful job and great pictures - it's amazing how sturdy these engines are

[9hellheaven]

Things getting further now all the tinware etc is back. I tried to post some pics last night but it wouldnt let me..any way here's a few more just to browse through if anyone enjoys just looking at engine bits and pieces.

Starting to take shape more now.

 

Heads just waiting for the valve gear to be fitted.

Lovely new guides all in place...the exhaust valves were desperate..shame i didnt get a picture of them.

 

Heads all built up by John and ready to be fitted.

 

Only two new rockers were needed due to the hardening starting to break up, no cam damage thankfully as we caught this early.

 

note the date stamps on the heads being April 1989 so a late car for the run out of the 930 i think? I replaced all the ajusters to on the rockers.

[9hellheaven]

heads and carriers going back on for another decade or two i hope! bye bye lovely pistons never to be seen again.

 

Heads are back in place and looking good!

 

Cam shafts being slotted into carriers with great care.

 

looks like an engine again now.

 

Note the layout of the tinware, all back and looking good in satin black. The only piece i had to replace was the front tin which was rotten.

[9hellheaven]

its all come up a treat and not with the usual pitting you tend to find after 20 years service. very pleased with it.

 

Had the bottom covers done which i left on the 3.2 as standard (wish i had'nt now). Top ones have gone of to have the "porsche" logo polished up so it stands out like the job i had done on the 3.2 last month. You can barely see them to be honest on the car, but what bits you can see show a nice attention to detail.

 

Got a big day on monday on the car so i'll bang the last few shots of the motor on. I have also bought a new sound deadening engine pad and the rubber trims in the engine bay to finish it off.

[9hellheaven]

Nothing to do with the engine, but ive been driving for months with a 4 inch crack in my screen so had a new one fitted. Was dreading any rust in one of the known hot spots, but all was well and factory fresh in the screen recess. Again pretty lucky, but in keeping with the rest of the car. Just a few last pics until next week.

 

 

I cleaned all the sealant off before the new screen went in. Not sure why it had been used in the first place. This was the cars third new screen at least.

[lexz32]

Nothing to do with the engine, but ive been driving for months with a 4 inch crack in my screen so had a new one fitted. Was dreading any rust in one of the known hot spots, but all was well and factory fresh in the screen recess. Again pretty lucky, but in keeping with the rest of the car. Just a few last pics until next week.

 

 

I cleaned all the sealant off before the new screen went in. Not sure why it had been used in the first place. This was the cars third new screen at least.

 

The late model year cars windscreens are meant to be bonded/sealant not sure if it was the 87-89 cars or just the 89 managed to break mine when trying to remove it for a respray

[9hellheaven]

Hi lexy, It's a bit of a funny one this. Here's my take on it. The guy from Autoglass said the screen should not be bonded, although i did clean out some sealnat from the previous screen. We used the same rubber, now here's the rub (excuse the pun) my screen rubber has quite a thick looking area of rubber seal on the inside of the screen. Now as i understand it (but could be totally wrong) this rubber seals were for the soon to arrive 964 series and did'nt need bonding.

I would of course stand corrected. I know from having a 993S that they are bonded, but the install is totally different as the screen is laid flat against the bonding/sealant and a rubber surround fitted over the top. The screen rubber on the 930 does look like its held on the lip of the appiture without glue. Guess we find out if it blows out at warp speed!!!

[lexz32]

Hi lexy, It's a bit of a funny one this. Here's my take on it. The guy from Autoglass said the screen should not be bonded, although i did clean out some sealnat from the previous screen. We used the same rubber, now here's the rub (excuse the pun) my screen rubber has quite a thick looking area of rubber seal on the inside of the screen. Now as i understand it (but could be totally wrong) this rubber seals were for the soon to arrive 964 series and did'nt need bonding.

I would of course stand corrected. I know from having a 993S that they are bonded, but the install is totally different as the screen is laid flat against the bonding/sealant and a rubber surround fitted over the top. The screen rubber on the 930 does look like its held on the lip of the appiture without glue. Guess we find out if it blows out at warp speed!!!

 

I was having a look for my bodywork thread where I got advice from Digger in regards the windscreen (cant find it for the moment) however you are right in regards the 964 seal which was what i used in the replacement which was also fitted by autoglass and they used sikaflex to bond it which was certainly what digger advised was the case on the later cars no doubt someone will chime in with words of wisdom. And the fact you had traces of sealant and mine was definately sealed would suggest this is correct