Thread: Mystery solved !!!!!!!!

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nows the time to think about getting that stock rocker arm set up off... its a pos and going studs .that too bad about the oil rings hasting is abit better to work PC are crap with the hastings they do not over lap as EZ .the new engines have gone to a thinner oil ring and are very easy to over lap or bend .i just did a mark 6 bbc were the guy bent the oil ring when he put it together it happens

There is no question we are going to take your advice on the Hastings rings, Pat. I looked at the ones we have on there last night and the way they butt up is not that impressive. What do you think about the .018 end gap on the top rings? The gaps on the oil rings looked wider, is that normal?

I also saw that on piston # 3 we inadvertantly put the two ring gaps in line on the 2 thin oil rings. Don't know how that happened as I always stagger the gaps, but it must have been late at night.

Don

Just some things I wanted to share here.

Don-you might want to take a hard look at the ring compressor your using.It doesn't take much,but a slight nick on the edge would cause you a problem going in.

As your putting in the pistons the walls are oiled up.Your turning the engine over by hand to put in the next piston.I suggest you watch the oil pattern on the wall of the last piston you put in.If you see anything weird like a line in that oiled cylinder,you stop and take out it back out to check it out.Not fool proof,but it might help catch problems.

That is a good point about watching the oil pattern, I'll do that. My ring compressor is a SnapOn that I have had for years. It has something like 4 different collars that fit different sizes of pistons,and a clicking plier setup that squeezes the collor tight around the piston. I will take a look at the collar to make sure it hasn't gotten nicked or otherwise damaged.

Don

same tool i use every week to put pistons in many years ago i ran a flap wheel in side my bands then wet sanded them with Wd40 to get the hi spots off the in side of the band .were they stamp the band size on the outside it was pulling steel down on the inside . after boring i break the edge with the boring cutter or a drum sander made for the job or by hand which way i do it has alot to do with how big the bore is to size of the fire ring is on the head gasket i use on the job. breaking the edge helps get the pistons down the hole and make sure there is no sharp edge at the bottom of the bore is this cut the piston skrits up so i sand the bottom edge of the bores as well after a bore and hone . .018 is the lest to use 016 is the lest for 2 ring .oil rails end gap can be very big 040+ as for getting one piston small out of a set i seen more then one its not hard to see 4 out of 8 that are under 001 that why i never bore and hone a block till pistons are in hand . i allways number the pistons for bores and bore the block to each pistons real size i hold less then .0002.5 and i allways check and fit the ring gap

You know, Pat, I will have to look at my ring compressor because I know that size stamp you are talking about. I will also wet sand mine, I have used them for so many years they might have gotten nicked or scratched. They nestle together inside the box, so maybe the one inside scratches the one placed on the outside of it.

Tonight I removed all the rings from the pistons and cleaned them up with a scotchbrite and some solvent. They all look good, but there is some scuffing on that black stuff they put on the skirts. Is that normal ?

I also want the machinist to look at the connecting rods and crank. The bearings seem to generally look good, but some have a little more wear on the outsides of the bearing, and some look like there is only wear on part of the circle, as if the crank journal is not contacting the entire circumferance of the bearing. Maybe the rod ends need honed to true them ?

The one piston, number 3 where the expander tip broke off, shows some scratches on the area above the top ring, that smooth area right at the top. It is only on about 1/2 of the piston top, and I think it was caused by the fragment of the expander or carbon getting lodged in there and scratching the piston. Should that cause any harm ?

Don