Thread: Engine oil burning

Tweet

I've rebuilt my .040 4 bolt 350 and used chrome rings. now after 1000 miles the engine still burns oil, all other fluids are OK.
Driving the car at 65 MPH @ 2250 RPM the engine will smoke lightly then suddenly smoke quite noticeably for a short period.

The engine has new heads, new pistons and rings, new PCV valve, I used Fel-Pro gaskets and Sealed Power pistons and rings. Bearings are new as well.

I've been told to use about half a soda straw of Bon-Ami cleanser to each cylinder or let the engine get hot.

Now how hot is hot? Got electric fans so allowing to produce heat is no problem.

Did my machine shop make a mistake in measuring my bores?

Please help,
Jerry P.

Have you run a compression check? Or better yet a leak-down test?

Pat

Whew, this post is very near and dear to my heart. I had the SAME problem. And I was where you are...people suggesting the bore was bad, rings broken, tear down the engine. There are too many things to do first before getting that drastic. So, here's my advice based on having the same problem:

Check the following first:

1.) Are ALL plugs fouled from oil? Only one or two? Only one side or both? If fouled, all over or just one side (put in a new plug and make about a 2 mile run then pull the plug quickly). This will isolate the problem.

2.) Did your intake gaskets slip and you are sucking oil from under the intake into the head? Were the haeds milled or angle cut causing a gap between the intake and heads?

3.) Are you sucking oil from the PCV? Take the PCV out and drive it. Any smoke? No, add a catch can between your vacuum line and the PCV valve.

4.) Find a fouled plug, replace it, then replace the valve seals on that cylinder. Heavily oiled top ends can suck oil past bad seals (even marginally bad seals). This was my problem.

5.) Leakdown test will show bad rings or cylinder wear. (Compression test is not good enough). You want less than 8% loss across all cylinders. It's so hard to believe you have bad rings or bore job. Unless you cracked a ring, scraped a cylinder, or installed the rings where all openings lined up, it's just too hard to believe there's a bad bore or cylinder related problem. However, you did say chrome rings...they take forever to seat. Possibly up to a couple thousand miles.

If it turns out that the rings are not seated, let them break in naturally. Don't do anything crazy like adding cleanser, transmission fluid, cutting oil, or let your engine get hot. That is not going to do you any favors in the long run...unless you like scrapping messed up iron and aluminum!

By the way, how much oil are you loosing?

Keep us posted on what you find above...

Did you use a engine oil additive? Slick 50 or something like it? I know some one who added it to the first oil put in motor and now with 6500 miles it still smokes!