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View Full Version : Update on my Banks turbo 6.2



Robyn
02-04-2007, 22:10
Well the beast is all apart now and mostly steam cleaned.
The bottom end was a 5 alarm train wreck but the block is fine.
Very little wear showing in the cylinders at all.

Have 2 cylinders that have some scoring. (BORE TIME)

The heads look wonderful.
I have dusted the deck surface of the block off with a large wire wheel on the big 9" grinder as well as doing the heads.

After steaming the heads off really good and cleaning the surfaces well, I
pulled the exhaust valves out one at a time and they are perfect.

My plan is to clean the valves/guides and springs as well as the rotocaps
in solvent and then reassemble them.
The precups on a couple cylinders have the usual small cracks in the port area but not at all bad.

I think one or two cylinders had a small crack between the valves but nothing to worry about.
The gaskets were pristine with no noticable degradation of the gasket at the water ports as one usually finds on a high mile engine.

The block is a 599 with a D144 date code.
It is a 6.2 and the bearing dates confirm the engine to have been built in 94

The bearings shells were stamped GM A250 on the rods and A200 on the mains with 9-94 dates on the rods and 3-94 on the lower main shells and 9-93 on the upper main shells.

This thing must have been a crate engine that was purchased to replace the original engine that had been in the truck.
The owner had paid some serious $$$$ last july to have the turbo installed.

It was run about 15K miles and the sucker went south, losing 2 rods and breaking a piston.
I am still at a loss for why it failed.
The thing was so badly thrashed that any real conclusions from the post mortem are not forthcoming.

The rods that failed were 5 and 6 most likely one failed then the other.
The nuts were barely tight but I blame that on the pounding and stretching things did.

The cam looked good but I tossed the lifters due to all the contamination.

The pistons and rods went in the round can also.
I have a 6.5 crank and rods and will replace the pistons with new.
Looks like some .5mm OS will due fine to freshen things up.

The turbo and all the kit parts look sweet.
The exhaust was cut in about 5 places to get it from the truck but I can slide some sleaves over the cut areas and weld things back together and all will be near new condition.
The exhaust pipes were not even rusty yet as was the muffler.

This kit was on a dually crew cab so I will need to shorten the center pipe a tad to fit the system on my Burb.

Not the way I wanted to get a Banks turbo system but OH WELL.

With the injectors and the pump off I will get them to the pump shop and have them tested and any needed work done so they will be ready to fly once the engine is back together.

I am thinking this little beast should make the old Burb truck down the trail in style.

All for now

Will keep the info coming as it unfolds..

Robyn

darkroad
02-04-2007, 23:03
Hi Robyn

Just got my cucv blazer 6.2 motor tore completely apart. Looks like it had about 20 to 30 thousand miles on it from the condition of everything. Crank will polish out standard. Just enough ring groove to have an excuse to bore it. Am going to have the shop square deck it also. Took the plunge this time and have low compression ceramic coated pistons, and the rest of what I need comming this way. Had them take off an extra .010 to compensate for the square decking. Will reuse my gear drive, freshly rebuilt IP and turbo injectors and heads off motor in suburban now. AM using ARP head studs this time and the girdle off the other motor.

Am going to coat the skirts myself . Next will be port match the clearwater heads, banks manifold and gm drivers side manifold and my J intake. Then am going to ceramic coat the manifolds, turbo housing and even the crossover pipe. Have a nice big Greive oven at work that you could stand about 10 people in it that runs at 400 all the time.

Found a good deal on flea-bay on a sandblast cabinet. Harbor freight has the same one for $300, found it for $165. shipped to my door. Am going to blow out the left side another 24 inches so I can fit the pipes in it to clean them before coating. Even got two rolls of header wrap from flea-bay deal on the banks kit with upgraded turbo.

Glad to see that yours is comming together. Post us a picture of the beast when you get it going. Still hard to imagine seeing you getting in and out of the high rise beast. Nice tho that you do what you want to when you want to.

Liked your article about pre-priming engine. Have done it both ways and feel its worth the extra trouble to pre-prime when you consider how much it takes to rebuild one anymore. Have a 383 stroker on the other engine stand for my 92 burb that I quit counting after 3 grand just in the short block.

Did you deceide to scrap the idea of going serpentine on this engine? Would a later 99 system that has the AC on the driver side give any more clearance for the turbo? I love the idea of getting away from the v- belts. I have had a lot of bad luck with the v belts and the harrison compressors. Have lost two now on different vehicles in the same year. Have to keep belts tight to keep them from slipping. Puts a tremendous load on the front bearing and seal.


Darkroad

Robyn
02-04-2007, 23:21
Sounds like your little military critter gonna be reeeeeel good when done.

I dont mind the tall beast most of the time, real beeotch in a skirt though.

I was reading Jims article on the fuel economy series and looked at the pics of the different precups.
My 6.2 has the ones with the 3 dots and the circle with the A in it (A)

This is definately a 94 engine and Im thinking that its most likely a Military engine from A Hummer or surplus.
After 93 I'm told that GM parts sold the 6.5 N/A as the replacement engine for civilian stuff.

Probably never know for sure but one can extrapolate from the available clues that it sure fits the discription.

I want to get the block magged yet and the main line checked for straightness before starting to put it back together.

Good luck on the cucv.

Robyn