Bearings were spun

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boomerang

Lifer
Jun 19, 2000
18,883
641
126
Originally posted by: illusion88
I didn't get the oil changed for about 5-6k miles. I know, bad. I must also have a small leak or it's burning oil. A friend of mine told me that all Honda engines burn a bit of oil. Not sure if that's correct or not. Either way, when I checked my oil after the knock started I was bone dry. I added 3 qts of oil and it just put it inbetween the lines on the dipstick.

So the route of the problem is a combination of me not changing the oil and the oil either leaking or burning over 5-6k miles.

Two of the caps and rod ends are discolored. Those are the two that had the burnt bearings. The cradle isn't discolored. It also fits back in easily. I haven't been able to get to the main journals, how much risk is it to just leave them there and hope for the best? Is that straight retarded?

I don't have an oil pressure gauge, but I bet Napa autoparts carries one.
Well, you know what caused the problem. In this case, that's actually a good thing.

To answer your question, I would change all the bearings.

Here's an old trick for removing upper bearing shells on main journals: You can only use this trick if the crankshaft is cross drilled. In other words, if there is an oil hole in the main journal. Get a cotter pin and bend it such that when you put it in the oil hole and turn the crank, it will butt up against the edge of the bearing shell and spin it out. Obviously, you want it to contact the shell only and not scrape the block as you turn the crank. Make sure you spin the crank in the correct direction. Pay attention to the tang on the bearing. It can only come out one way.

I can tell that you are going to replace what you can and hope for the best. That's OK, lots of folks learn from their mistakes. I have one question for you and then I'll let you have at it. Where did all that damaged bearing material go?
 

lsd

Golden Member
Sep 26, 2000
1,184
70
91
You're better off replacing the long block. You can always part out what's salvageable from the old block to make up some of the cost.
 

exdeath

Lifer
Jan 29, 2004
13,679
10
81
You need to have the crank machined down and the new bearings will have to be the same size larger. You also need to check the assembled rod caps for roundness and have those machined as well; I guarantee the rods and caps with the spun bearings are out of spec for roundness, and it may not be possible to machine them without making them shorter. Ergo, new rods. It's not as simple as just replacing the bearings. Remember we are talking about thousands of an inch, or 0.001".

And this isn't even getting into other damage with main bearings, piston expansion/collapse and scored cylinder walls, valve train damage, oil pump, engine balancer, etc, or anything else that needs oil.

If you have a magnetic drain plug, look at the metallic goop forming magnetic stalagmites on the end of the plug, and imagine that abrasive suspension being pumped throughout the engine in it's last 100 miles.

There is a reason why it's easier and cheaper to just replace the engine with a low mileage used one. Unless you're building up a killer B series or something, it's not worth the cost or effort, even as a learning exercise. You're better off learning by spending that money on building up something worthwhile from scratch that didn't involve oil failure and not spending $2000 to rebuild a stock $200 engine for a daily commuter.