Compression for 500E 123-127
 

I've just had a PPI done on a 92 500E. The dealer felt like the car was in overall good condition, and that the compression was from 123 to 127. I thought the lowest acceptable pressure was 190. some feedback, please. I am going to have them re-do the test, and to do a leakdown test.
Are there conditions that can impact a reading? Hot, cold?
Help! I want this car, but not if its not straight.

Tom

Hi Tom,

I recently had a PPI done on a 93 500E and the compression results ranged from 155 to 157. This was in high altitude and as I understand it air density is less at high altitude thus lower numbers. Anything below 150 would be something to worry about. A really good engine would be around 170 near sea level.

I found this information on an earlier thread , if I find it I will post it for you to read.

By the way I never did get the 93 so I'm still looking too.

Good Luck and I hope this helps.

autotrader.com has a wealth of info on 500e/e500's available for purchase...most very low mile examples and a couple of Starmark cars too

good luck
-fad

We looked at a 1992 500E that was for sale last summer for $30,000. That's a REALLY low price in these parts for a 500E.

I had the car checked (best $160 ever!) and we found dry compression to be 130 on a couple cylinders. Most were in the 145-155 range.

Run away! That car has NOT seen an easy life.

I thought about buying the car, and using the difference in it's price and a good example to bring it back, but why bother? God only knows what else has happened to the car.

Depending on the gauge used and the person testing, I've seen readings as low as 130 to as high as 160 on my car. I've always maintained that what is more important is the relationship of the readings across all cylinders - i.e. are they all within 10% of each other. Try getting it re-tested at a different garage, or try testing it yourself. Just my $0.02...

As stated before, there is important that the cylinders are consistent accross the board. I do not know what the specs are for the 500E, but I imagine 190 psi would not be the correct number, it seems way too high.

Just a little info to add to this thread. I just have a 30k service completed on my 92 500E and had the shop do a compression test as well. Here are the results;

1 - 190
2 - 180
3 - 190
4 - 185
5 - 180
6 - 180
7 - 180
8 - 185

So, if I take the guages accuracy as gospel, my cylinder average is 183.75 psi and the 10% rule would let 18 psi swing up or down.

What do you Technicians think, does this sound accurate? What do you think Guido? Not sure if this was don Hot or Cold, whats the difference?


BTW, engine has 173600 miles on the Odo and has had dino oil all it life until 5k ago.

roas,

Those numbers are great from what I have seen. I recently had a compression test done on a 92 500E with results ranging from 170 to 176, and this car had 55k on the clock. Makes me wonder if the numbers I have are good or bad.

Placo1, I wonder to if the numbers I have are a little on the high side, I mean this engine as seen 176k+ miles, and the last 15k I put on it where a little heavy on the Accellerator pedal side. :)

The PO maintained the car as a fleet vehicle so it had a nice thick stack of receipts and services performed with checkups every 2 months.

Just goes to show those people out there considering a higher mile 500E to add to there stable, these engines will LAST a long, long time , just take care of the known issues.

Michael, Guido, are you guys going to publish that 500E / E500 "known problems and fixes" list? :)

As far as the numbers being good or bad, I believe a Hot test is more accurate than Cold as the cylinder walls, piston rings, etc. have all had a good chance to expand to operating temps.

Maybe this is your case? If anyone is curious I believe a "Leak-down" test is even more accurate and telling of the internal condition of the engine.

Can anyone verify?