The interference engine.
10-03-2006, 02:39 PM
#16
Rennlist Member
Originally Posted by Lizard931
AFAIK, all 32V are interferance,
all 16V are not,
I say all 16V as I have a 1985 euro S2 and when I did the timing belt service noone could tell me if it was interference or not, so with the belt off and the cams at TDC I manually very slowely turned the crank over, there was NO interferance, so I moved the cams 180 deg tried again no issues, cams back to TDC and still no issues. Once I completed the timing belt service which included all seals, as well as the dual distributor belt the engine fired up on first revolution and ran flawlessly.
and with the comment on the engines which have the 45 dg mark, I think that says only 32V engines again.
all 16V are not,
I say all 16V as I have a 1985 euro S2 and when I did the timing belt service noone could tell me if it was interference or not, so with the belt off and the cams at TDC I manually very slowely turned the crank over, there was NO interferance, so I moved the cams 180 deg tried again no issues, cams back to TDC and still no issues. Once I completed the timing belt service which included all seals, as well as the dual distributor belt the engine fired up on first revolution and ran flawlessly.
and with the comment on the engines which have the 45 dg mark, I think that says only 32V engines again.
Alex
1990 928 GT
1984 928 S2 5spd (GTS tranny)
10-03-2006, 02:48 PM
#17
Nordschleife Master
I have no idea what the deal is then, but I know what my results are/were,
the car in question is a 1985 Euro S2 with the dual distributors, and from what I can tell there is nothing to say that the engine has ever been opened up. The car was picked up from the show room floor in germany by an american drove it to the boat, flew back to the us and privately imported it. It came from the 2nd owner who lived in ohio. It was a high mileage car though 272,000 or so miles on it.
But I did confirm that nothing touched. I am not going to say that spinning at a high RPM they wouldnt touch as there may be alittle valve float on that high of mileage.
the car in question is a 1985 Euro S2 with the dual distributors, and from what I can tell there is nothing to say that the engine has ever been opened up. The car was picked up from the show room floor in germany by an american drove it to the boat, flew back to the us and privately imported it. It came from the 2nd owner who lived in ohio. It was a high mileage car though 272,000 or so miles on it.
But I did confirm that nothing touched. I am not going to say that spinning at a high RPM they wouldnt touch as there may be alittle valve float on that high of mileage.
10-03-2006, 03:24 PM
#18
Rest in Peace
Rennlist Member
Rennlist Member
Join Date: Apr 2003
Location: Penn State
Posts: 2,240
Likes: 0
Received 0 Likes
on
0 Posts
Some of my observations, for data points purpose only:
79 5 spd 60k miles, broken belt: no valve damage
85 auto seized h20 pump, stripped 12 teeth off belt at 70 mph, NO valve damage.
86.5 auto 143k miles seized h20 pump circa 140 mph, stripped 8 teeth, 30 bent valves.
88 951 oil soaked/aged belt, stripped teeth, no valve damage.
YMMV
79 5 spd 60k miles, broken belt: no valve damage
85 auto seized h20 pump, stripped 12 teeth off belt at 70 mph, NO valve damage.
86.5 auto 143k miles seized h20 pump circa 140 mph, stripped 8 teeth, 30 bent valves.
88 951 oil soaked/aged belt, stripped teeth, no valve damage.
YMMV
10-08-2006, 07:14 PM
#20
Instructor
Thread Starter
Join Date: Apr 2006
Location: NJ, Czech Republic, Russia
Posts: 244
Likes: 0
Received 0 Likes
on
0 Posts
What this thread has told me is that everyone has an opinion, some quite adamant ones, and no one knows anything at all. Most disappointing!
10-08-2006, 09:08 PM
#21
Originally Posted by rhys
What this thread has told me is that everyone has an opinion, some quite adamant ones, and no one knows anything at all. Most disappointing!
If you were wanting a yes or no answer, I'm sorry, there isn't one. The users were just trying to sum up the exceptions. Too bad you didn't read it that way.
Dennis
The following users liked this post:
bartontb (06-26-2021)
10-09-2006, 12:23 AM
#22
Rennlist Member
Originally Posted by rhys
What this thread has told me is that everyone has an opinion, some quite adamant ones, and no one knows anything at all. Most disappointing!
I for one didn't take any chances and changed my TB right away.
The following users liked this post:
Jakalu (03-27-2020)
10-09-2006, 12:44 AM
#23
Addict
Rennlist Member
Rennlist Member
Yes, I've thought about buying a non-interference car....but not sure which is which. If they all have the potential (carbon, etc.) I'll stick with the higher HP newer 928s.
Harvey
Harvey
10-09-2006, 12:27 PM
#24
Advanced
Join Date: Jan 2004
Location: Valley Forge, PA
Posts: 60
Likes: 0
Received 0 Likes
on
0 Posts
I'll add my 84 Euro experience for the record. I had a bent valve as the result of a passenger side cam tip failure. Just 1 valve "slightly" bent - though thats all it takes to lose compression in a cylinder. The bent valve makes a nice desk paperweight.
- Kevin 84 S2
- Kevin 84 S2
