Disaster at #2 !

[Rob C]

http://www.imagestation.com/picture/sraid134/p4d31565dc4b2ab5eb0c5ad17735dba62/f76935f0.jpg http://www.imagestation.com/picture/sraid134/pe70eb7b9ca4e6a096a514bd887649b20/f769360a.jpg
My #2 combustion chamber and piston !! :(

The hole in my piston is possibly from a leaky injector (yet to be determined). It looks as though my precup fell apart, then bounced around between the piston crown and the combustion chamber for awhile (because I drove it for about 5 miles after the racket started, to get it home).

Can this head be re-used ? I was thinking that a new precup could be inserted, then a valve job on this chamber, and I might be OK. Or is this the end ?

The cylinder wall appears undamaged... no gouges or sratches. Can't get the piston out until I get a ridge reamer to remove the carbon buildup at the top of the cylinder, but I think I will be OK with new rings and a honing (will be re-ringing the other 7 pistons). When I get the new piston, should I get a new con-rod (and have it assembled from whoever I buy it ?) I think the piston pin is pressed into the piston and I don't have a press to remove/reinstall, so I am leaning to a preassembled replacement.

For those who have re-ringed before, what did you use to check the cylinder for out-of-round and taper ? Mitutoyo makes a nice instrument for this purpose, but it looks like many $$$$. Haynes manual shows it being done with a telescopic bore gauge and a large micrometer to measure the gauge, but if I recall correctly from my machine shop class, a lot of practice is needed to use these properly. Any tips ?

Thanks !

[Dezman125]

Hi
You can change the piston pin your self. It is held in by clips.If the head isn't cracked you should be able use it.You should be able to get it presure tested at a machien shop.
Good Luck

[Rob C]

Thanks for the encouragement, and the tip for the con-rod.

Does one of the DP advertisers sell a complete gasket kit for a 6.2 ? (heads, intake, front cover, vacuum pump, injection pump, etc...)

The R&R guide mentions using Felpro 6.5 head gaskets instead of 6.2 gaskets, because the 6.2 gaskets did not have very round openings for the bore. But I think I recall someone else saying this was not a good idea. Your mention some controversy in your post "Air bubbles in overflow tank"... I guess this is the problem ?

Is there a recommendation on new rings ? I know little about them, other than following the Haynes guide for making sure that they fit OK.

All tips are appreciated !

Rob

[Dezman125]

Hi Rob
I havn't gotten mine apart yet,was almost finished this afternoon but had to come home and watch our daughter.
As to the contraversy about the 6.2 or 6.5 gaskets,i havn't heard or read much about it.
I'll know tomorro if it is a cracked head or gasket,or worse :( Well at least i drove it in the shop.

[Dezman125]

Hi Rob
The head cracked from the precup to valve.Must have been weakened when the truck lost antifreeze and overheated befor i bought it.The other head was cracked the same place. This one was checked and resurfaced.My bad luck i quess,time to find an other head.

[Diesel-Direct]

Well if you were going to go and re-ring a worn 6.2L engine. In general we have seen these engines wear the cylinders in an oval shaped pattern so if you throw new rings into a dingle berry honed hole... you're gonna have nice round rings in an oval hole... leading to where the engines won't have enough compression to start and break in the rings.. or have gobs of blowby... atleast put a real stone hone on it and a minimum.. as for checking bores etc. enco sells a "peacock" dial bore gauge set for like 0-6". It's a very accurate set for the money. Just need a mic to set it. as for the difference between the 6.2 and 6.5L head gaskets.. I think our victor reinz sets come with 6.5 head gaskets in the 6.2L box from the factory so it becomes a non issue. Ring quality? Mahle rings are cheap and OEM.