TedH

All,
I performed the Dry compression test. Instructions that came with the gauge said to warm the engine up to operating temp. Now, I don't know about you guys, but I am averse to poking around an engine after it has just reached operating temperatures. HOT HOT HOT! Instructions said to remove all of the plugs (I assume while the engine is still nice and toasty). I skipped the warm-up step.

So, I tried the Dry compression test on a cold engine. Not sure if it invalidates the readings but at least I don't have 2nd-3rd degree burns on my forearms.

The readings:

1,3,5,7: 166-167psi, 172-173psi, 169-170psi, 169-170psi
2,4,6,8: 165-166psi, 164-165psi, 160-161psi*, 169-170psi

All readings were within 5% of the highest readings with the exception of #6 which was just a tad over 5% off of the pace.

Valid test? If valid, I don't think the reading on #6 was that serious since it was not far from the average reading. BTW, I charged the battery after the reading on #4 (it was the sixth cylinder tested). I may go back and test #2 and #4 just to be sure.

Feedback welcome! :seeya

GDaina

The readings are consistent... :thumbs:

Though you would have gotten a much better sample had the test been on a hot engin.

zwede

I take it the test was in your quest to figure out the PCV oil consumption? I still think you need a leakdown test. Engines can do great on a compression check while having very marginal oil control and high blow-by.

Your compression readings look fine, BTW.

74droptop

:iagree: I've tested my engine like you have had readings around 210 but still have oil control problems haven't done a leak down test yet.


[Modified by 74droptop, 4:35 PM 3/27/2004]

TedH

ok. I may have to wait a couple paychecks for the leakdown test but it will be done...

Appreciate all of the feedback! :seeya

wayne_69_427

The idea behind a copression test is to see if all cylinders are equal. Yours are all right there, if you had a cylinder a lot lower say 100psi then you would have a problem.