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Thin oil car won't start

1998 Honda civic LX, 125,000 miles. New plugs, wires, distributor, battery 2 years old. No problems but car engine turned over but would not start. Took in to garage and mechanic said oil too thin. Oil not getting to piston ring to create compression. Car is running fine now, does this sound funny?

There is something to the theory, but in practice, I have never heard of it. I would think that you would reach the point where the oil was not providing enough lubrication preventing the starter from turning the engine over fast enough before it would fail to seal well enough to reduce compression to much.

I would think you would have to have 50% gasoline and 5 weight oil to cause either of the above. However I could well be wrong, it just does not smell right.

The test for this is to squirt some oil in the cylinders and see if it fires up. Washed out (by fuel) cylinders will cause a loss of compression and a no start,but not from the use of “to thin” oil. What are you using sewing machine oil?

I saw a really bad eaxmple of something like this. A DIYer bead blasted his cylinder heads (so he could paint them up nice) Put the heads on, engine fired right up died in 5 seconds,finally it was determined no compression,oiled it up fired back up no problem. About 1000 miles later every bearing (even cam bearings)were worn out in that brand new small block.He did not get all the bead blast medium out of the heads.

Thanks, oil was change recently at garage (oil level OK). Sparks plugs removed and oil squirt into cylinder, then started.

It sounds very funny to me. Thin oil moves more quickly than thicker oil, so the thin oil should have had no problem getting where it needs to be.

If you’ve been using the oil recommended by Honda in your Civic there should not be a problem. I’m guessing the owner’s manual recommends 5W-30 oil, which is NOT too thin.

If switching to a thicker oil solved a compression problem your Civic should have been burning oil for some time. Has it been burning oil?

What viscosity oil did the “mechanic” put in the engine?

What kind of oil did you have in it?

If you had 5W-30 or 10W-30, this should not have been an issue. If you had 0W-20 oil in the engine, it might make sense to me.

My 1998 Civic DX with 185,000 miles has never had this problem with the proper oil being used.

Oil change March 09 (Wisconsin) viscosity of oil not mentioned.

The rings are probably trashed or stuck from carbon or oil sludge. Once washed down, they no longer provide a good seal. Ask the mech if the oil stunk of fuel. A chronic, severely leaking injector(s) could dilute the oil significantly and wash down the cylinders.

How was the car running prior?
What is the oil change history?

The only time I have ever seen the need to squirt oil into the cylinders to get an engine to start is when the engine uses an updraft carburetor and an engine was either rebuilt or left standing for a long while (ie little or no oil on the rings).

I rebuilt a tractor engine with an updraft carburetor and learned the hard way that a squirt of oil was needed to seal the rings to generate enough vacuum. When I called a Ford tractor dealership mechanic, he said they had to squirt oil into the cylinders of all the new tractors that were unloaded from the factory. Otherwise they wouldn’t start.

Updraft carburetors are a thing of the past.

A couple of weeks before we had the last problem the car was difficult to start after we were running around town but after that it was OK for a couple of weeks. Then it sat for 2 day and then it wouldn’t start. The car has been running fine before and after, doesn’t burn oil and gas usage same.