6.5L Diesel questions

I am considering buying a 3/4 ton Chevy Truck or Suburban with a 6.5L Diesel. Although not as good as the current generation diesels offered in light duty trucks, it still would be a good compromise between my budget requirements and still being able to enjoy the virtues of a diesel engine.

Now this leads to my question. In looking at used 6.5L '94 to 2000 trucks and '94 to '99 Suburbans, I would like to know what things I should be looking for and what kinds of questions I should be asking. I am thinking that a truck with approximately 100k miles might be my starting point. I know that the 6.5L is not perfect, but at the same time, it is a very serviceable engine. Are there certain things besides the obvious things that need to take place with a 100k mile 6.5L diesel as far as maintenance? For example, I hear that the injector pump is something that seems to be relatively costly to replace. When does a part like that usually go out? What else do I need to consider with an engine of that age and mileage? Any ideas or comments are welcome.

Thanks,

Scott

Reply to
Scott
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From what I understand, the 6.5L diesel is just warming up at 100k.

400k is probably a worn out diesel, but then diesels never wear out there just due for a rebuild.

My question; are the injectors in these engines rebuildable (like all REAL injectors should be?

-The Lonely Grease Monkey

1985' 305CUI TH700R4 NP203 K5

"Ignorance is preferable to error; and he is less remote

from the truth who believes nothing, then he who believes

what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey

Two of the ranch trucks we have have well over 300k on them and they still run strong. Ours have had turbos added on which makes it a little nicer to tow with. I was hauling 4 ton of hay this weekend without a problem. The

Reply to
sidewinder

"Lonely G-Monkey" wrote in message news: snipped-for-privacy@posting.google.com...

news:...

I've got the 6.5L GM diesel in a '93 3/4 ton pickup. 173,000 on it and no engine problems at all except the combination oil press. sw./oil press. sending unit. The switch controls the electric lift pump on the LH frame rail and is known to get burnt contacts and not allow full voltage to the pump. Causes hard starting and hesitation. There's a serv. bulletin on this and a newer model switch to solve this. Very common problem. Also, '93 was the last year of the full mechanical injection pump, the '94 and '94 models had problems with the electronic injection pump. From what I've read on it, the '96 and on engines had this ironed out. If it was me, I'd stay away from them. For prices on rebuilt pumps and injectors, I used this dealer in Texas.

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The 6.2 was in an '85 pickup and I put the Banks turbo kit on it. Had the overhauled injection pump, rebuilt injectors and 235,000m. on it and ran very good. Gave it to my 18 yr. old son when I bought the '93 and he rolled it and totaled it inside of two months. Another problem you could run into is the seal around the throttle shaft input on the injection pump leaking when the engine is cold. The fuel will run down the lifter galley cover and off the back of the engine and the leak seems to be from that area. The seal can be replaced with out tearing the pump down. Haven't done the job, but looks like no big deal from looking at the service manual. I'd advise going to the following website. These guys have got all the information you'd ever need on these engines.
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In my opinion, these are very good engines. Hope this helps.

Garrett Fulton

Reply to
gfulton

To the original poster:

Here you have some awesome feedback on these engines. The one thing I can put down ontop of this is: When I was working on my transmission I had someone who told me dead up it was my tranny (he was right) and said he had put FOURTEEN (14) trannys behind his 6.5L die-zell with over 400k on it. Die-zells are made to run till the cows come home, have children, their children are eaten and the gluttons die of heart failure.

Like a rock

Reply to
KJ

Then again, my 95 GMC 3/4 ton has almost 417,000 and it has only had the second transmission in it (4L80E) but then it is acting up and will be diagnosed tomorrow. Maybe I am in for number three?? or maybe just solenoid and control repairs??

Right about the 6.5, when properly cared for it is a very tough engine. Just don't get confused and think that it is a Cummins. That can be very disappointing.

George

KJ wrote:

Reply to
George Vigneron

I had an 82, 4X4 4 speed. Ate a lifter at about 73K miles. About six months later the injector pump died. The trouble with the pump was the coupling inside fell apart and the debris stopped up the relief valve. I fixed it myself and sold the truck. That truck was good for 22 MPG around town. I sold it because parts for them are expensive and I had enough. I think I paid a little less than $50 for the lifter, and about the same for one rocker arm. I wanted to replace the cam and all the lifters but the prices were unbelievable. The newer 6.2's have different rocker arms and I was going to change the rockers and shafts, again too expensive. Detroit Diesel built the early ones, then Chevrolet took it over and redesigned some of the internals. One thing I remember, I started it up with the intake off. You could shine a flashlight in the intake ports and watch the valves open. Try that with a gas engine:)

If you wrench on your own trucks, the 6.2 is not easy to work on. There is no hole in the valley like on a gas V8. I had a hell of a time getting the lifter out of the engine through the head. And a worse time getting the new one back in.

Al

Reply to
Big Al

Sounds like you had a difficult relationship with your 6.2, sorry.

I put over 200,000 on a 84 6.2 in a Suburban. When the odo reached nearly

300,000 a piston skirt let go. I built a 6.5 NA for it last year, found it to be a pleasant experience. My pickup replaced the Suburban. So far on this 6.5 (I am not the original owner) I have had to change the injectors ( which means removing the turbo on the passenger side) and I have changed the pump. I got a replacement pump off ebay for $108 and had it checked out at the local Stanadyne shop for $150. The injectors cost me $43.50 each new, not reman. Should have done some more ebay shopping for them but didn't have the time. When I first got the truck I didn't have the oil pressure I wanted so I dropped the pan and changed the rod bearings and the mains. Also the oil pump because it was wasted. Periodically there have been glow plugs to replace but those don't count, too easy and cheap. Oh yeah, I have gone through two PMD's but now have fabricated a heat sink and mounted it remotely so that should all be behind me. First one came from a dealer, second one came off ebay for $25. Love that ebay!

I am still getting to know the ECM but that will take some time. I do my own wrenching because I enjoy it but I don't mess with the transmission though. Some things are best left to those who have the experience and specialty tools to do the job right. Maybe someday......

I can't imagine the noise of firing the engine without an intake.

My experience with 6.2's and 6.5's has been mostly good, as opposed to my short experience with a 5.7 powered Olds.

George

Reply to
George Vigneron

G-Monkey Will Attempt To Merge Two Posts Into One

Hard tellin not knowin, I'm no expert. I thought how many he chewed up was insane, I have no idea how hard he rode it but I figured it out and it was about every 29k he put in a new one. My book, unacceptable. Your milage I'd be very happy with.

More proof scott, go chevy, and haggle over the "high millage" but feel safe in buying it.

Good milage is always nice.

There "made to last" so they should be a bit more, but I don't remember any parts like that being "outrageous" in my agg die-zell klass. Where were you buying?

One thing I do know is, die-zells are ment to be worked on, and have indevidual parts REPAIRED, not replaced. Personally I'd never think of trying to get a lifter out through the head.... what did you do tip the truck upside down and shake it?

Personally would have pulled the valve covers, & heads. Cleaned all the grime off the heads (don't have to worry about it falling down into the engine) a new head gasket and check for any kind of debris ontop of any of the other lifters. Perfect oportunity to check valve clearance as well..... This keeps the truck in good running shape for little more cost (head gasket, brake cleaner, elbow grease and maybe some frustration)

How much did you sell it for, and in what condition was it in (interior etc.) Remember the OP is looking to buy one, so your real-world experience might help him. $0.02

-The Lonely Grease Monkey

1985' K5 305CUI TH700R4 NP203 KJ's successor

"Ignorance is preferable to error; and he is less remote from the truth who believes nothing, then he who believes what is a wrong." - Thomas Jefferson

Reply to
Lonely G-Monkey

Right after I posted my previous message, I went out and started the 6.5 and then looked under it. Fluid was pouring out of the front seal (obviously because it was coming from the dust cover weep hole). A mechanic friend had changed me to the new Mercon V fluid just before vacation. Now I am very suspicious about syn transmission fluid. I figure I am in for a total rebuild, at the very least all of the soft (neoprene/rubber/nitrile... and so on) parts.

Any experience with this new fluid?? Mercon V

George

L> G-Monkey Will Attempt To Merge Two Posts Into One

Reply to
George Vigneron

"Lonely G-Monkey" wrote in message news: snipped-for-privacy@posting.google.com...

Well, I owned the truck for a little over 10 years and sold it for $9,500. A few hundred more than I paid for it. Keep in mind the prices of new trucks more than doubled in that same period.

My engine had a lifter fail by breaking the needle bearings on roller. The roller locked up and skidded on the cam. Made a flat spot on the roller. With the needles gone and the flat spot on the roller the engine was making a loud tapping sound. I pulled the valve cover on the noisy side and found the problem in a few minutes. The 6.2 has plates with squared off holes in them to keep the hydraulic roller lifters from turning. The heads have a funny shaped hole that will allow you to remove the bolt that holds the plate. (GM was smart enough to make the bolt captive.) And remove the plate and lifters through the hole. I used a lasso made out of small diameter brazing rod to remove and install the lifters. This will be very hard to believe, but my engine was super clean inside. No sludge or grime. Hard to believe it was a Diesel. One thing I noticed was it took a long time for oil to make its way to the top of the engine. About two minutes from an overnight sit. Two minutes is a long time when parts are running with no oil. When I look at trucks now I stay far away from Diesels. For my money a Chevy gas engine is good enough for me. My last Chevy truck was a K30, 454 with a TH400. Great truck except it devoured gas. 7 MPG empty:) I read this newsgroup just to glean information about the new 8.1L big block. So far what I have gathered is not good:( I tried to buy a 8.1L six speed but couldn't find one. After a while I found one in Las Vegas, but it wasn't the truck I wanted. Why are all the 8.1's quad cabs?

Al

62 Chevy II, 406, TH400, 9" Ford. Street legal. 10.90's @ 123 MPH so far.

2002 Z28, six speed.

2002 Cavalier, five speed.

Dodge W250, five speed.

Reply to
Big Al

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