GPM

Blower motor with gas in the oil, three of the lifters were gaulding into the bores.

TWIN-SPINS

articfriends was talking about this,,,look up under his posts,,,hope this helps http://www.offshoreonly.com/forums/g...w50-oil-2.html

getrdunn

Jim,
What did actually tell it would take to solve the problem and what is it that is acutally wrong wit them. I have never seen a BBC with bad lifter bores. Actually once I did after I completely grenaded an engine and had shavings everywhere. It was one of those were you could put your fist through the oil pan. Needless to say we just ran a hone through them and they cleaned up fine. Never had any issues after the rebuild. If you ran the engines for a number of years with no problems then.............. If he is saying that they are beyond acceptable tollerances I guess I would have to see it with my own eyes. I get real anal sometimes with rebuilds wanting absolutely everything perfect and it can drive me nuts and also go without paying the heat bill. Sometimes I also try and fix things that aren't broke and end up regreting it. I'm not saying not to be concerned with it but then again sometimes these kind of fixes can actually lead to other issues. You'll probably tear them down every couple of years for inspection and bearings anyway I would assume. As long as the cam lobe hits center on all lifter gallies and they are within tolerance. Well I guess you gotta do what you gotta do. I know your sinking some big bucks into these things and you want them right and I completely understand that. Keep us posted with the details. Your going to run rollers aren't you.
Good luck,
John

getrdunn

I simple fix for that would be just use heavier springs.

Just kiding/////

minxguy

Gas in the oil thins the viscosity of the oil you are using and the thinner oil does not have the same film strength as the non-diluted oil so load carrying benifits goes away and metal to meatl contact comes to visit.

I would think that that if your oil was diluted enought to cause lifter bore damage, the bearings would all be junk, not to mention the rings.

Ken

1BIGJIM

My question was about 'bored to the next size withoug liners?

Please explain, never heard of this.

ezstriper

If you have a carb flooding issues and the oil get diluted with fuel, it will kill the bearings and such in a heartbeat...I found out the hard way....took so little it was unreal, killed a crank because of a powder coated float bowls and hang the float..seems to me you would kill the crank and bearings like I did way before the lifter bores...why did you pull the engine down ? Rob

1BIGJIM

That was an interesting article. The machine shop is looking at my second block now, I was shocked when he told me and need to ask again exactly what is wrong with block #1. I don't think they went thru the time to put the true lifter jig on it.

jeffswav

A few years ago I had a flat tappet lifter that was not rotating correctly. It caused a cam lobe to flatten out and then Boom!! A piston went lean and blew a hole in it. I simply had the lifter bores honed out and have not had any issues since. I have since upgraded to a full roller setup. If the lifter bores are out of line that is a whole other story. Like was said before a lot of them leave the factory that way and unless you run them at 6k+ RPM it may never cause you any problems. I am not a engine builder, this is just what happened to me and what I have heard from other people. Good luck with your project!!

Ebay Ed

on small block chevys there are actually 3 different size lifters that they use in the race cars .842 which is stock .875 which would be for an over bored lifter bore and .904 which is a stock Big Block / Mopar lifter bore on the aluminum blocks they use for sprint cars most of them now use the .904 lifters and i think it is because the roller bearings in the lifters are a little bigger and can take the abuse of a sprint car a little better