KCS

iTrader: (20)

In the last few weeks, I have been working on rebuilding the stock engine for my F-body. I got the engine out and finally got around to tearing it down last weekend and I noticed the main caps are loose. No register in the caps at all, except for number 1.

The bearings look pretty decent, no signs of excess heat in the caps, so I'm kind of stumped as to how this could have happened. I've only seen something like this two other times, once in a freshly machined sleeved block and another in an engine that spun the mains pretty badly.

So I'm just curious, has anyone out there seen something similar?

mark21742

I'd say you got VERY lucky....I've never seen that on an engine that didn't spin a bearing....guess the two small outer bolts coming in the side of the block saved the mains?

KCS

iTrader: (20)

I guess so. The bolts were all tight, but once they were removed, I could take the caps out with two fingers!

mark21742

Oh ok lol I thought you were saying the bolts were finger tight.....yeah every ls block I've messed with I had to tape and pry the caps off

KCS

iTrader: (20)

Same here. I'm pretty sure the block is junk now, but I may try to dowel the caps like the LSX block to try and salvage it.

mark21742

I had mine align bored and my crank turned 10/10 in iron block and everything worked out great

KCS

iTrader: (20)

I don't think that will fix this problem. I was thinking I'm going to have to dowel the inner main bolts like the LSX block.

In the meantime, I have another block that I was saving for my Mustang that I'm going have to use to replace this one. Oh well.

XtraCajunSS

iTrader: (2)

Just change the caps. The block is not the problem, the caps have stretched.

Shane

KCS

iTrader: (20)

Hmm, what makes you say that? I appreciate the advise, I'm just curious how you came to that conclusion. That is probably the last thing I would expect.

XtraCajunSS

iTrader: (2)

Anytime I've had that issue, I've just replaced the caps with known good ones and had the block align honed. Under high loads, the crank is trying to push the caps out of the bottom of the block. They tend to walk around a bit and deform. Sometimes when they are loose, you can have them cut and have the block align bored and they will fit tight again. I usually have a fair amount of used caps laying around so I normally replace them.

Shane

KCS

iTrader: (20)

I'll look into that, thanks.