1997 850R Compression test results

mattman · Post by **mattman** » 18 Sep 2013, 09:48

: This is at idle, previous photo at 2500RPM

Post by **jblackburn** » 18 Sep 2013, 10:42

If it smokes constantly, your PCV desperately needs cleaning.

If after just idling/sitting for long periods, you need stem seals.

Compression looks OK.

Post by **rspi** » 18 Sep 2013, 10:53

I RUN Mobile 1 because it's hard to find any other 10W-40 in any other full syntheitcs. I have had good results and a very good report from Blackstone Labs.

Double check for a loose vacuum elbow. One may have come off.

Post by **mikealder** » 18 Sep 2013, 11:15

When you cleared out the PCV did you check the lower port on the front face of the engine where the PCV tank connects was clear, best way is to connect a length of 5/8" rubber hose to the port and try to blow through it, if you hear bubbles from the sump then it is clear, if you can't blow through it the port is blocked. I had to pull the sump to clear it out as it was packed with carbon - Mike

mattman · Post by **mattman** » 18 Sep 2013, 12:16

Hey folks, just finished leak-down test,
9%-8%-10%-9%-21%
All within "good" guidelines...

PCV was done pretty methodically last Feb., although I don't remember blowing into the motor.
Good tip tho...

Great write-up on motor oil too, think I'll do a quick switch back to dino oil, and see what happens.

Post by **rspi** » 18 Sep 2013, 12:19

I would go 1 step thicker than to go back to dyno. Yuk!

mattman · Post by **mattman** » 18 Sep 2013, 12:23

Will do.
Opening filler cap while car is running launches oil out.
No, I didn't over-fill...
I think the Synth is just too viscose in 100 degree weather with engine running.

Post by **jblackburn** » 18 Sep 2013, 12:24

mattman wrote:Will do.
Opening filler cap while car is running launches oil out.
No, I didn't over-fill...
I think the Synth is just too viscose in 100 degree weather with engine running.

Not really. Synthetic should be fine, especially in high temps.

Put a latex glove on top of the filler cap hole. Does it inflate?

mattman · Post by **mattman** » 18 Sep 2013, 12:26

No, it almost sucked it in.

Post by **jblackburn** » 18 Sep 2013, 12:27

mattman wrote:No, it almost sucked it in.

Oh, that's good news for the PCV theory then.

That's fine, cross that one and bad rings off the list.

Yep, 10W-40 step-up sounds good...but I would stick with synthetic, especially in hot temps.

1997 850R Compression test results

Re: 1997 850R Compression test results