Originally Posted By: VolvoBruce
My very very bad.
I just redid the compression test.
First time, forgot to hold the throttle open.
Now:
200-190-187-180, dry.
Sorry for posting it wrong earlier.
We bought a 1990 Honda Civic LX with the 1.6L 4 cylinder SOHC engine. Reading your experience brought back memories of excellent fuel economy and a real dog climbing steep hills with 4 people aboard. Nice car with panoramic view of the road.
We had the Civic in the family for 14 years. It was traded in in 2004 towards a used Dodge Caravan. It had 160,000 miles and still got 40 mpg highway.
Oil usage was its Achilles heel. Roughly 1 qt every 1000 miles just like you said. I went to 10W-40 "Certified" from Sam's Club and oil usage went lower to about 1 qt 1500 miles. As I recall, the oil usage was upsetting because the engine was so small. Compression was good just as you reported. It was the valve guides that were worn. The oil delivery in that gallery is a little less than generous and any hiccups in the OCI cycle creates sludge and causes guides to run hot and dry. To sum it up, the engine's performance remains decent and the gas mileage continues to impress but the oil usage was very high for the size motor: valve guides all the way. The SOHC oil delivery was to the camshaft which leaves the valve guides to either side of the SOHC and they get whatever runs off. Put a little sludge in there and you have guides running hot and dry.
Here is what I did: 1) keep the oil topped off to the extent of 1/2 to 3/4 quart over and never let it get to "add". 2)ignore the 5W-30 Honda recommendation which is for a new car or an engine without excessive wear. Go to a 10W-40. When you are adding a quart every 1000-1500 miles, you can go further on the OCI cycle but don't exceed 5000 miles. I stayed with dino oil because the oil usage cost precludes a synthetic and the oil looked pretty clean on the dipstick even at 4000 miles. 3) Run 16 oz of Rislone (small sump and 1 qt is a lot for that little 4-banger) with each OCI and put in the other 16oz the second time you top off at about 2000-2500 miles. The engine will remain very clean and the oil will continue to reach those guides.
Another idea which may help but wasn't available when I was extending the useful life of our 1990 Civic 1.6L SOHC: add a can of LubroMoly MoS2 Engine Oil Additive. It will help reduce the excessive valve guide clearance because it will fill in all the metal roughness and lubricate the moving parts better than an oil wedge. You may want to replenish the MoS2 particles every OCI. You only need half of the 300ml can each time you add it (small motor!) so you will get 2 OCI's out of each can. I paid a very, very reasonable $4.29 at NAPA and the product does reduce internal engine friction.
I put LubroMoly (about 180ml) in my wife's 2.5L 2008 Nissan Sentra SER and didn't tell her. She came back from visiting the grandchildren and says "I don't know what was with my car today but it felt real peppy. Did you put something in the fuel?"
