Tomorrow HybridCRX and I will begin disassembling my Lsvtec to install new rings. A few minutes ago, I did a compression test and the numbers were as follows:
Cylinder #, and PSI
- 250 PSI
- 250 PSI
- 270 PSI
- 260 PSI
This is after I increased the viscosity of the oil, by running 20w 50 synthetic, and CD2 anti-oil burning additive, and 8 cylinder restore, Smoke-Fix additive, and changing the oil filter. (The original owner used 10w 30 non-synthetic.)
Approximately 3 weeks ago, I did a compression test on the engine before I bought the car. The compression numbers were as follows:
Cylinder #, and PSI
- 260 PSI
- 255 PSI
- 220 PSI
- 225 PSI
Also, the spark plug on number 3 cylinder is always heavily caked with oil when I remove it and clean it.
The engine burns 1 quart oil every 100 miles, and that condition has not changed.
Along with heavy amounts of smoke emitting from the exhaust pipe when I lay on the throttle, or engine brake.
My question is, why did the #3 cylinder increase 50 PSI, and cylinders 1 and 2 decreased? I’ve used restore before on a Honda Civic with bad compression, and it did absolutely nothing to the static compression. (Although I did only use the 4 cylinder quantity of Restore.)
Could the increase in oil viscosity have increased the static compression of the #3 cylinder with horrible piston-ring-blow-by, by 50 PSI? If so, why would it do that?
I’m still perplexed as to why the compression increased a substantial amount, when usually the case, is that compression worsens over time.
(BTW, the pistons are SRP 11.5:1, bored 81.5, with unconfirmed brand rings.)
Any explanations are appreciated.
-Andrew