Head Questions

[ironridge]

Hi all, first off great site lots of good info. A bit of my history. first diesel 1981w/the converted 350 olds worked great for me sold it at 80k and bought 85 k2500 6.2 Bought a new k2500 6.2 in 1990. Still got it. 200k on it. bought a k2500hd new in 02. love that duramax. So the only one I missed was the 6.5 , until yesterday. Just picked up a 97 3500 HD 6.5 T/4l80E deck truck W/70k original miles. The truck belonged to a lumber yard and it just ran around delivering lumber. Got a steel of a deal. Here is the catch. The guy told me that it was diagnosed w/ a blown head gasket(bought this from a broker)the truck come in from the west coast. No rust, its like new. Anyway I ask the guy if I can start this truck he agrees, so I bump her over by hand for a couple of revs. As we can't see a level in the surge tank I put a couple of gallons of coolant in it and she fires right up it had not been started in over a month. Right away I can see the evidence in the tank bubbling and you could see and smell coolant in the exhaust. Then I notice a small puddle of coolant developing under the engine.I start snooping around and find a heater hose laying against the turbo down pipe. As soon as I touched it it stared spraying. So I say to the guy That it probably has been run out of coolant and likely has cracked heads. He swears that the leak is a new issue. Anyway he knocks the price down some more and I hauled her home.:) Have yet to tear into it but I was looking around for some prices on heads. Here is my question , there is a guy up in Calgary ,Alberta advertising new castings completely dressed with new valves and springs for $700cdn. Has anybody dealt with this guy, he claims they`re 567 castings, do you think they are gm.
http://cgi.ebay.com/ebaymotors/6-5-L-Turbo-Diesel-Cylinder-Heads-New-with-Valves_W0QQitemZ220099539246QQcmdZViewItem?hash=it em220099539246&_trkparms=39%3A1%7C65%3A1%7C240%3A1318&_trksid=p4506.c0.m245
Any advice would be helpful. Thanks

[76m880]

i have a set on mine and they have done me well

[Robyn]

The issue with your new little friend may only be a gasket and nothing more.

The end cylinders have a habit of blowing into the water jacket as it was not until recently that Felpro introduced a reinforced gasket that has a steel support around these areas. Cyls 1 and 7, 2 and 8
My 94 lost the gasket at the front of number 2.

The heads on these do crack between the valves and this is normal as long as they dont hit water. If you find a crack on the firedeck its game over for that head.
he precups can crack in the corners of the port window and it fine as long as the crack does not cross the fire ring of the gasket.

Also check the number 8 cylinder (RH REAR) in the 7 oclock position when looking directly in from the RH side of the block. about 1 inch down from the deck, some blocks cracked radially around that lower quadrant and would leak coolant into the cylinder.
This will be quite evident as the cylinder wall will be a dull gray and etched in the area.

Finding this is a game over forthe block. The 6.5 is not a good candidate for a sleave as the walls are too thin and after sleaving the head bolt holes want to crack out into either the lifter chamber or the outside of the block.

The issue with the heads from sources other than GM has been beaten around here a bunch.
I have used heads from Clearwater in Florida and had great luck.
As was mentioned the guy up north has some good stuff too.

There is some junk out there so be careful as to who you use.

Yank the engine apart and not only check the heads but wash the block well and check main webs on the center 3 around the outer bolt holes in the block for cracks.

These cracks can be right through the theaded holes and down the web or they can start in the corner of the register fit where the main cap sits and run off down the web.

Cracks in this area are NOT GOOD
I have seen a couple blocks that had a single small crack in one hole repaired by drilling the lower end of the crack (very short only about 1/4" long) and installing a stud kit into the outer holes with red loctite.

Welding is not an option on these blocks.

Some companies make a stud girdle device for the 6.2/6.5 engines.
Debatable as to whether these do much.

If you find major cracks of any length reaching down the main webs the block should be considerd a door stop.

I have seen engines with less than 100K with bad cracks and others with over 200K with zero issues.

Its a real pig in a poke thing. No real way to predict what you will find.

Some have suggested that a stick shift is more prone to cracking, others seem to think its ralated to gear ratio and how much lugging.

The one issue that seems to raise a red flag all the time is the condition of the harmonic damper and the rubber dampened serp belt crank pulley.

A failure of these components can quickly destroy a crank and a block.

The cranks in these engines are a cast (Nodular) iron unit and do break.

I have seen a couple in pieces and its usually very ugly.

Have fun with the new toy

Robyn

[Yukon6.2]

Hi
I have experiance with the seller you are showing from ebay.You can do a seach on this site and find the post that i wrote at the time.
I wouldn't take a free lunch from this seller let alone send him money for chinese knock offs.
He was a member last year here for about a month then vanished after a few people started asking two many questions for them.
If you send him money and you arnot satisfied,you will be in for a fight to get any of your money returned.
There are lots of reputable vendors for 6.5 parts,including vendors that will be up front about their chinesse stuff.
Good luck
Thomas

[76m880]

Hi
I have experiance with the seller you are showing from ebay.You can do a seach on this site and find the post that i wrote at the time.
I wouldn't take a free lunch from this seller let alone send him money for chinese knock offs.
He was a member last year here for about a month then vanished after a few people started asking two many questions for them.
If you send him money and you arnot satisfied,you will be in for a fight to get any of your money returned.
There are lots of reputable vendors for 6.5 parts,including vendors that will be up front about their chinesse stuff.
Good luck
Thomas



i must have gotten a good set

[JetBoater]

I am dealing with a company who has been repairing 6.5 blocks for the past 4 years. He buys all the blocks he can get his hands on... Note: not all can be repaired.

If you find your block has crack(s)... PM me and I'll be happy to provide contact info.

I have had a block repaired.. I just need to have it shipped to me and pay the bill. I'll start a thread on this once I get it back and begin assembly. Its not cheap but includes an align hone, required after cracks have been repaired.

The work comes with a guaranteed... again I'll provide more info when I have it.

[Busted]

JetBoater, is the company you're referring to located here in Canada? I have a couple candidates if the repair is cost-effective . . .

[JetBoater]

Affirmative. I am not sure of the company name at the moment... as my repair was arranged through my friend's local shop. The company is in BC.

I'm also not sure why my mechanic wants/likes to keep his subcontractors "Top Secret".

I have 2 more blocks to repair if this one goes together and doesn't explode into $5000 dollar pieces. ;)

[ironridge]

Thanks all. When I get around to tearing this thing down I'll update. I'm hoping just for a gasket.I don't think this is going to be too bad as there does not appear to be any coolant in the oil or oil in the coolant.

[Blinkinlights]

Great thread guys. I just ripped the heads off my 6.5 J because I was losing about 2 litres of antifreeze every tank of gas. There was no water in the oil and the engine still made plenty of power. It looks like the head gaskets were recently changed by the PO and even with the coolant loss, the head gaskets showed no damage. Here are some pics of what I found:

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0470.jpg

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0471.jpg

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0463.jpg

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0465.jpg

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0466.jpg

http://i5.photobucket.com/albums/y174/bANGr/Chevy/IMG_0467.jpg

I'm hoping that it's just the heads, not the block but I don't have the time to rip apart the whole motor. There is a guy in Norfolk ON that has the complete heads for $515 plus about $20/head shipping.

My question for you guys is do you think that the cracks in the heads in the top two pics could account for that much coolant loss?

Greg

[Blinkinlights]

Well. I decided to take the plunge and purchase only one complete head from http://norfolk.kijiji.ca/c-cars-vehicles-parts-accessories-GMC-Chevrolet-6-5L-Diesel-Cylinder-Heads-W0QQAdIdZ24772027
for $515.00CAN, that's $423.64USD plus shipping, only $40CAN to Edmonton, AB from Norfolk, ON via Greyhound. I asked the guy and he said that the heads are cast in Germany...whether that's the Deutches Republic of Germany or the little known Germany, China I don't know. ;)

We are going to try the one head and see if the problem is solved and hold our noses and not check the bottom end for cracks.

I'll keep you guys posted on this source for heads.

Greg

[pjt97k2500]

I just did my head gaskets and heads. Picked up a set of rebuilt heads from Precise Engine Rebuilders in Calgary for $500 each. The heads came from a rebuilder in Quebec. Just finished the project and the truck runs. I have no miles on them yet.

[JetBoater]

I am looking for some decent precups for my heads... anyone have 8 of these babies? PM me with a price if your interested in selling. Thanks.