Main Bearings.

[campbellWS]

When i googled glyco bearings i found this on a performance vauxhall forum, thought it would be of interest.



Bearings
I use the normal Glyco bearings which are wider than the AE version.
I no longer use sputter bearings as I have found they wear the crank.
I have glyco bearings big ends and mains.

Steve

[JP]

Sputter bearings are harder than the normal tri layer bearings. I have found several engines that have not run sputter bearings where the softer tri layer bearing has crushed and leads to early failure on turbo engines.

The bearing itself is a non contact item supported on a film of oil. The only reason you would see damage to the crank is if either the engine has been starved off oil or impurities are in the oil as the sputter bearing being harder cannot absorb these which is why you run the softer tri layer bearing in the cap where it does not receive the crushing loads to help absorb small particles.

The later I5's rarely need a regrind from bearing failure if neither of the above problems have occured unlike the earlier 10v's which run the same cranks with no sputter bearings which require regrinds all the time on rebuild.

[DJones]

Sputter bearings are harder than the normal tri layer bearings. I have found several engines that have not run sputter bearings where the softer tri layer bearing has crushed and leads to early failure on turbo engines.

The bearing itself is a non contact item supported on a film of oil. The only reason you would see damage to the crank is if either the engine has been starved off oil or impurities are in the oil as the sputter bearing being harder cannot absorb these which is why you run the softer tri layer bearing in the cap where it does not receive the crushing loads to help absorb small particles.

The later I5's rarely need a regrind from bearing failure if neither of the above problems have occured unlike the earlier 10v's which run the same cranks with no sputter bearings which require regrinds all the time on rebuild.

Great post.. I think its pretty hard to obtain none sputter sets now..

For reference i get my bearings (KS) and rings from IMEX and they deliver to your door..

Darren.

[campbellWS]

I have broken down a 144,000m aby engine for a 500hp+ rebuild, all parts are in a1 condition and the main bearings are like new, not even a hairline mark on them, would it be rediculous to use them again? I understant that if they are out anyway why not replace them but as i said they are perfect, would there be any advantages

thanks

[DJones]

Personally I would just replace them. 144k miles is 144k which ever way you look at it. To reach your goal reliably everything needs to be right.

[campbellWS]

good plan! i just thought it was worth an ask. many thanks

[ManiacuV6]

Can i hear an opinion at least about 034motorsport main bearings .I seen on the website that the bearings are coatet with "a special layer". I have an early AAN and i want in the future to do a rebuild. Thanks!

[JP]

That sounds like the calico coated bearings. Which are stock tri layer bearings with microfilm of dry lube coating. I had a set custim coated for my personal engine to see what difference they may make.

The only time they come into play is if you rev the engine 8000+rpm and get oil cavitation where the dryfilm lubricant coating prevents the bearings picking up on the crank. Other than that they make no difference as your crank is aupported permanently by a film of oil during operation.

[andy10v]

Could they help save an engine from momentary oil starvation due to slosh?

Photos here of a set that were run for 5-10 min with no oil pressure (assembly lube on though), and then 2k of use.

http://www.motorgeek.com/viewtopic.php?f=18&t=32877

[20Vcqdriver]

Out of curiosity, has anyone using glyco bearings ever used 'plastigauge' to see what the clearance was? Done this on mine and they seem to be out of spec at 0.065mm on the main and 0.07mm for the big end. Or is this acceptable??

[Pirvu Eugen]

I used them in my engine and..on both..mains and rods were 0.05mm.

[20Vcqdriver]

I used them in my engine and..on both..mains and rods were 0.05mm.

So are mine out of spec and is it OK to take a bit off one of the shell edges to reduce clearance, or is that as I suspect a big No No!

[Pirvu Eugen]

So are mine out of spec and is it OK to take a bit off one of the shell edges to reduce clearance, or is that as I suspect a big No No!

NO WAY....measure the crank....for sure is out of spec...