Compression range
Compression range
04-29-2005, 03:05 PM
#3
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145-150psi is the "average" range for a good engine compression. But bear in mind, the test must be carried out when the engine is at operating temperature (oil and water, not just the water), and the throttle should be wide open.
04-29-2005, 04:00 PM
#4
Three Wheelin'
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mine checks 150 - 155 at all cyl fully warmed up.
Its important to have these engines at Full operating temp
when testing compression as they expand a lot.
Also make sure you have the throttle full open when testing.
Its important to have these engines at Full operating temp
when testing compression as they expand a lot.
Also make sure you have the throttle full open when testing.
04-29-2005, 05:06 PM
#5
Three Wheelin'
The factory spec for new engines is 10 bar or higher, which is roughly 145 psi.
Gauges vary, and atmospheric conditions cause some variance as well.
Your numbers are acceptable. A leak down test will tell you if the valve work was well done, or it the rings are getting some wear. If the valves are tight, I would run it as is.
Gauges vary, and atmospheric conditions cause some variance as well.
Your numbers are acceptable. A leak down test will tell you if the valve work was well done, or it the rings are getting some wear. If the valves are tight, I would run it as is.
04-30-2005, 01:58 PM
#7
Nordschleife Master
Similar readings across cylinders is very important too. If yours are all within that range, that's good. Gauges read at different levels, so your engine muight be in great shape. 132-134 is fine.
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04-30-2005, 04:33 PM
#8
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yesterday i read 150 155 150 150 on my motor. i had it warmed up to maybe the bottom of the water temp gauge (takes a bit longer cause I'm running about 90% water) the intake manifold was still luke warm, like i wanted it not to burn my hands. So the oil and water temp were a lot lower then operating temp.
Maybe the pressure in the crankcase isn't the rings afterall! Any ideas?
~Eyal
Maybe the pressure in the crankcase isn't the rings afterall! Any ideas?
~Eyal
04-30-2005, 05:56 PM
#9
Three Wheelin'
Eyal: have a leak down performed and that will tell you the story. I think you need to re-align the oil filter housing on the block with the proper tool before you go blaming the rings. Make sure you have the proper oil pressure relief valve for your block.
04-30-2005, 06:10 PM
#10
Eyal - you TO PAY PARTICULAR ATTENTION TO NOT CREATING ADDITIONAL RESTRICTION WITH ANY SORT OF AFTERMARKET CATCH CAN IF YOU HAVE NOT OPENED THE TOP OF THE AIR/OIL SEPERATOR.
I have personally experienced restricted oil DRAIN from the turbo and consequent oil through the turbine because the oil could not drain into the crankcase.
I have personally experienced restricted oil DRAIN from the turbo and consequent oil through the turbine because the oil could not drain into the crankcase.
04-30-2005, 06:28 PM
#11
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Originally Posted by special tool
Eyal - you TO PAY PARTICULAR ATTENTION TO NOT CREATING ADDITIONAL RESTRICTION WITH ANY SORT OF AFTERMARKET CATCH CAN IF YOU HAVE NOT OPENED THE TOP OF THE AIR/OIL SEPERATOR.
I have personally experienced restricted oil DRAIN from the turbo and consequent oil through the turbine because the oil could not drain into the crankcase.
I have personally experienced restricted oil DRAIN from the turbo and consequent oil through the turbine because the oil could not drain into the crankcase.
Cruise, i will be realigning the oil cooler housing, these are sepearte issues. The car is popping the dip stick. Could it just be something dumb like the o ring on the dipstick is worn, and the dipstick is vibrating itself loose?
~Eyal
04-30-2005, 07:00 PM
#12
Three Wheelin'
"yesterday i read 150 155 150 150 on my motor. i had it warmed up to maybe the bottom of the water temp gauge (takes a bit longer cause I'm running about 90% water) the intake manifold was still luke warm, like i wanted it not to burn my hands. So the oil and water temp were a lot lower then operating temp.
Maybe the pressure in the crankcase isn't the rings afterall! Any ideas?"
Didnt I guarantee you?
I am positive that your problem is the OPRV housing. Do it!
Maybe the pressure in the crankcase isn't the rings afterall! Any ideas?"
Didnt I guarantee you?
I am positive that your problem is the OPRV housing. Do it!
05-01-2005, 10:00 AM
#14
Three Wheelin'
Eyal:
Make sure your vacuum lines are hooked correctly routed. Some are connected before the turbo, and some after. OPRV should not cause the dipstick to pop out. With those compression #'s I would not suspect the rings are worn out.
Make sure your vacuum lines are hooked correctly routed. Some are connected before the turbo, and some after. OPRV should not cause the dipstick to pop out. With those compression #'s I would not suspect the rings are worn out.
05-01-2005, 11:54 PM
#15
Originally Posted by Peckster
Similar readings across cylinders is very important too. If yours are all within that range, that's good.
Having two cylinders side-by-side with lower numbers is a good indication of a blown headgasket, such as 150-130-130-150.
I personally just saw 142-142-143-144 on my semi-warm 103,000 mile 88 951. While those numbers sound pretty good I think I'm going to do a leakdown test anyway for ****s & grins.