The truck is rough idleing, excessive blow-by with oil coming out of the dip stick and where it can come out from. I removed valve covers and looked at lifters and rockers. I cracked all injector lines and #6 made no change in the pitch of the engine. I tried a couple of other injectors on the # 6 and it made no difference. I have not checked the compression. It appears the #6 cylinder is dead.


Any help will be appreciated.Edited by: quantum mechanic

Quantum, I have seen it once before.... on a 95 on #8 cyl. You can do it with the engine still in the truck. If you need a piston, lemme know I have some laying around.


James

It is looking like a cracked piston. I would greatly appreciate that.

That happened on my '93.


When it went, I lost some power and was blowing white smoke out the tailpipe. I had about 2 miles to go and by the time I got there, the engine compartment had a good coating of oil and the dipstick was about 6 inches out and it had blown the CDR out of the valve cover.


One of the piston had a piece that cracked right out and was about a 1/4" hole. All the rest of the pistons on that side also had cracks in them. (I didn't ever pull the other head) This happened at about 240,000 miles.

I'm pulling the turbo side head tomarrow but my truck is not at home so I'm stuck in the city with no wheels.


This truck starting blowing by two years ago, so it's amazing it made it this long.Edited by: quantum mechanic

The head came off with minimal effort. The #6 piston is cracked from left to right with a big piece missing in the valve recess.


http://www.dieselplace.com/forum/uploads/quantummechanic/2004-10-31_150057_pistoncrack1.jpg


The compression on #6 was 0 when I checked it before pulling the head. All other cylinders wwere firing'cept #6 and they looked good except for a little carbon build-up. The plan is to replace #6 piston and put it back together. I noticed zero sealer on the headgasket. I thought it shoud be sealed in with RTV sealer?


http://www.dieselplace.com/forum/uploads/quantummechanic/2004-10-31_150405_pistoncrack.jpg

Is that pits in the piston from water or damage from debris in the cylinder?


On race engines we spray high heat aluminum paint on both sides of the gasket and quickly installed the head. Don't think RTV goes on a head gasket. Have use spray-on copper coat sealer also.

What's wrong with #4?


Bring it top the top and foto it, and #2 and #8.........Edited by: gmctd

Mine did the same thing on cyl. #7, I've been searching for some advice from someone who has seen it before. Mines has some pretty good scratches on the cyl. wall, I'm thinking about honing it out, still in the truck, and replacing just that piston/rings. any thoughts ? I'll check bore size first to see how far out I am.

Mine did the same thing on cyl. #7, I've been searching for some advice from someone who has seen it before. Mines has some pretty good scratches on the cyl. wall, I'm thinking about honing it out, still in the truck, and replacing just that piston/rings. any thoughts ? I'll check bore size first to see how far out I am.

how you ever going to get the abrasives out and not lose your bearings?

Jim

I found a piston for $35 and I do not know about honing because I have not seen my cylinder yet. I suspect the previous owner did not have the $7,700 worth of engine repair he paid for. He got new heads only.

Where did you get the piston? I'm not going to buy one until I determine the block is usable though. keeping my fingers crossed, need to keep the cost down.

I found the piston for $35 at Airline Autoparts (Salvage) nearby in Houston, Tx. I will give you the number if you are interested.


I had to pay $280 for a ring set, $180 gasket, and $40 bolts.

Might want to use some softer piston return springs. Get the ones with the stainless rotaters seats. The rotaters cut down on heat fatigue and reduce stress on the piston itself.

QM,


You aren't seriously doing a 1 hole only repair, them pieces and parts went someplace, that "grit" went thru the entire oil system, you would be money ahead doing total overhaul.

dont forget the camshaft rotational dampener, as there is no sense in having your cam shaft spinning at 7500+ rpm tearing up the engine! And while you are at it, get the engine bypass oil kit as there is no sense in getting your expensive oil contaminated by the engine block!http://dieselplace.com/forum/smileys/smiley2.gif http://www.dieselplace.com/forum/smileys/hihi.gif


BTW - how hard is it to pull the heads from the engine? I imagine not very complicated just tedious....

[QUOTE=Turbine Doc]


QM,


them pieces and parts went someplace,





The turbo could be damaged on the tips of the fins on the exhaust side. Hard to see without taking the exhaust housing off.

there is a 94 6.5 on ebay for $2000. 170,000 miles, says it ran good and didnt use any oil, but its got a bad pump. its in mississippi and if you buy it now he will give you the auto tranny for free. just a thought.http://www.dieselplace.com/forum/smileys/smiley4.gif

She lives!


It was a two day knuckle busting greasy creeper ride but I drove home the 70 miles from the city nice and slow to break the new rings on #6 in.


I learned that the piston is aluminum. and that you can't get the oilpan off a K3500 without significantly raising the block out of the engine bay. I've never previously attempted what I just did and I won't know how well it all went 'till it breaks again. that could come before 10,000 miles or after 100,000, I'll know then if it was worth it but for now, $500 in parts and my labor have put it back in running order. It may get a fresh block eventually, this will buy some time till then.

Can't you just drop the front differential a little instead?

I'm thinking the lift's for the IFS would give the front axle enough drop. I looked at the mounts and the a arms and I thought it was more than I wanted to dissassemble.Edited by: quantum mechanic

compared to removing heads and replacing pistons, removing the entire front axle and brackets is easy and straight forward. I've done it a couple of times. Finding (and going past) the limitations of the IFS's four wheel ability.

I never got the pan out of the way. I worked around it. It made it harder to do what I had to.