Hi everyone,
Would like to ask your opinion about my compression test results on my b230ft in a 250K + mile 88' 740. The car sat for 3 years before I stated driving it again 2 years ago. Lots of blowby, no piston slap.
Not sure on the accuracy of the gauge I used but I got ~120psi wet and dry in cylinders 1,2,4 and ~80 psi dry, 120 psi wet on cylinder number three. I performed the test correctly, however only ran the car for a few minutes before starting (temp gauge maybe 1/8 of the way from cold). Last compression test I performed, maybe 30K miles ago, gave me ~135psi on all four and the car was at operating temperature.
Other than the poor results the car runs and drives just fine, idles a little rough when first started, with decent power and boosting to about 10psi. Last couple of 180 mile highway journeys at 75mph gave me ~26mpg and I average ~22mpg with combined driving.
You think I'll be alright continuing to drive to work and that?
I'm hoping it's stuck piston rings that I can free up. What do you think the chances are that the number 3 cylinder has broken ring lands or rings or just wore faster than the rest? Or, what's the chances that cylinder #3 has stuck rings?
I don't have the time, money, or garage to open up the engine, hence trying to get informed opinions. Thanks for any good or bad news you may have for me.
Would like to ask your opinion about my compression test results on my b230ft in a 250K + mile 88' 740. The car sat for 3 years before I stated driving it again 2 years ago. Lots of blowby, no piston slap.
Not sure on the accuracy of the gauge I used but I got ~120psi wet and dry in cylinders 1,2,4 and ~80 psi dry, 120 psi wet on cylinder number three. I performed the test correctly, however only ran the car for a few minutes before starting (temp gauge maybe 1/8 of the way from cold). Last compression test I performed, maybe 30K miles ago, gave me ~135psi on all four and the car was at operating temperature.
Other than the poor results the car runs and drives just fine, idles a little rough when first started, with decent power and boosting to about 10psi. Last couple of 180 mile highway journeys at 75mph gave me ~26mpg and I average ~22mpg with combined driving.
You think I'll be alright continuing to drive to work and that?
I'm hoping it's stuck piston rings that I can free up. What do you think the chances are that the number 3 cylinder has broken ring lands or rings or just wore faster than the rest? Or, what's the chances that cylinder #3 has stuck rings?
I don't have the time, money, or garage to open up the engine, hence trying to get informed opinions. Thanks for any good or bad news you may have for me.