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Changing 1994 6.5 For 1990 6.2

H

handcannon

Well-Known Member
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Location
Albany, OR
My 1994 K2500 pickup motor, with electronic IP, has massive blow-by, uses/loses oil, and what sounds like a collapsed lifter. I'm on a very limited income and can't afford to rebuild, or replace with something like an Optimizer, or even a military take-out. I finally found a used 1990 6.2 NA out of a Suburban that I could afford, supposedly with only 144K miles on it. I thought I knew all that was needed to swap all my peripherals from the 6.5TD to the 6.2NA, but I came up with something I had not expected.

The front of the 6.5 crankshaft has a reluctor on it for the Crank Position Sensor, the 6.2 doesn't, which I was aware of. I was under the impression that swapping the reluctor over to the 6.2 crank would be easy. I haven't pulled the reluctor off the 6.5 crank yet, but the reluctor appears to be keyed onto the 6.5 crank. The 6.2 crank doesn't have a keyway cut into it beyond what is needed for the timing gear.

Once I pull the reluctor off the 6.5 crank what can I do to key the reluctor to the 6.2 crank. without pulling the crank and having a keyway cut? Unless there is a way to do this without pulling the crank I'm stuck. If that's the only way to continue with the swap I will just have to repair the lifter problem and put the pickup back together with the blow-by and oil useage.

I do have pictures of both crank snouts, but I have no idea how to add them to this thread. This afternoon/evening my daughter will be available to help me figure the picture problem out. But, until then I won't have any pics.

I know that War Wagon has successfully used 6.2NA mil take-outs in place of a 6.5, but I'm not sure if he has had to utilize the electronic IP like I have to. I don't have the funds to swap over to a manual IP system. I need to get my pickup running again, but inexpensively.

Don
 
The reluctor parts should swap no problem. I dropped a 1986 6.2 longblock in my 1995 with the DS4 electronic IP. Used new Cloyes timing set if it matters.

I highly recommend you (overhaul) put new rings in whatever engine you are dropping back in. A timing chain should be done as you are there. That is Rings ~$60.00, New head bolts ~$10.00 per side, oil pan gasket, and Head gasket ~$50.00 per side, Deglazing drill stone tool if you don't have one. I don't even pull the crank to deglaze cylinders to reduce new stress cracks. You get to see the rod bearings and know the rest of the shape of the engine. New front oil seal and look hard at the rope seal rear main.

Ebay for bearing, oil pump, and timing chain kit is like $350

Carefully check the turbo as it can be a source of oil usage as well. Look hard at valve stem seals and valve guides in the head for oil usage as well. It's best to use the 6.5 heads if you can, but, budget wise the 6.2 heads will work if: you header wrap them and optionally use 2 manifold gaskets on the turbo manifold. It will still be very tight up to the injectors requiring manifold loosening to change injectors.

Additional cost savings: I found 6.2 long body injectors will work on 6.5 TD setup heads.
 
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I'd be glad to handle donations on new parts and even include a part or two of my own.. If anyone has existing parts you can donate them directly to Don.

What all do we need?
If it all works out maybe the 6.5 is the better choice to rebuild? I have a new top ring and oil ring set (no second ring) I can donate (fits standard bore 6.5), would be a good time to get the 2nd ring in a gapless?
 
I have a new stock diameter crossover and a new 6.5 timing set available. I I read this correctly this will swap. I just made sure I could I find it as I spent 2 days looking for injectors for someone recently. Don, when you read this PM me and I get these parts out to you if you want them.
 
I've been sitting here scrolling back and forth trying to make sense of what I'm seeing/reading. All I can truly say is that I'm overwhelmed. My only intention for posting was hoping and praying that there was an inexpensive answer to my dilemma, and instead there is an outpouring of help and hope.

Thank you to all!

Because of what has happened here this post is going to be long, or maybe I will need to break it up into multiple posts.

First, I will try to give a condensed background. My motor has been having blowby for a while now, but I just figured I could live with it. Then the noise started, which definitely sounds like a collapsed lifter to me. I had to have a backup vehicle for those times when I needed one (three vehicles and three drivers), so it still got driven at times when I had no choice. It took a while, but I finally found the 1990 6.2 at the same time as I had just enough extra funds saved up. So I started to do the swap. I got the motor, transmission and transfer case out, and started pulling parts off getting ready for the swap. I got both front housings off and started comparing them. My thought was that the reluctor was separate from the timing chain sprocket on the crank.

Well, ak diesel driver was able to give me the correct configuration for the reluctor/timing chain sprocket as being all one piece. That takes a big load off my mind. Thank you!

ak diesel driver said:
reluctor is part of the crank gear. have you tried swapping yet?
Click to expand...

ak diesel driver said:
Your 6.5 should look like this
Click to expand...

ak diesel driver said:
Your 6.2 should look like this
Click to expand...

ak diesel driver said:
Even if you only have one key it should work
Click to expand...

I'm going to have to continue this in the morning. I'm slow at typing, and I feel that these posts deserve a very careful and well thought out replies, which takes time for me. I'm not a very good night owl, and it's getting late for me.

Don
 
Don, i think you just need to figure out what you need and witch block is the best candidate. Then it'll be easier to tell what parts you need and what we can help with.
I'd be glad to help with what I can. AK, WW and Rob are willing to help, who else is in?
 
Get the engines torn apart and see what the bloks and heads look like, I've got a set of lifters with 70,000 miles on them for your thought of a bad lifter. We need to know what else we are looking for.
 
Just a quick note. I haven't gotten lost, just prior commitments have kept me buried in stuff (church, and volunteering to help church womens groups' rummage sale set up). Been into town already this morning and had to get the van back for my daughter to use. I have another prior commitment to finish in the next couple of days. Then I can have time to assess the motor situation.

Don
 
I thought I would have time yesterday to do more, but it didn't happen. We sold a pup, so we have the funds to go to my family reunion this weekend. Consequently, we spent most of the day getting things done ahead so being gone for the weekend won't put us very far behind when we get home Sunday.

I do have a couple questions though. I looked at the timing chain on both motors and now have a question about how to measure for chain stretch. Do I measure for extreme stretch, or ? By extreme stretch I mean, stretch the chain as far as possible outwards, then as far as possible inwards, and measure the difference? Or, use a straight edge between the two sprockets, push the chain inwards as far as possible, and then measure the maximum deflection?

The second question is about checking for main web cracks, mostly to see if my memory is correct. First, with the motor upside down and pan off, carefully clean each web, then clean again using brake cleaner to remove all traces of oil. Then leave upside down overnight and then check for any cracks that show oil traces on the metal surface.

When I pulled off the front cover on the 6.5 I was met with a big surprise. Somebody has apparently had the pan off before. On the front end where the pan and front cover meet the silicone gasket maker had been put on so heavy that it had squeezed out so far that the squeeze-out was almost touching the lower timing chain. I wonder if a chunk of silicone came off somewhere and caused my "lifter" knock problem? After we get back home I'll get my son or daughter to show me how to post pics.

Don
 
QUOTE="handcannon
I thought I would have time yesterday to do more, but it didn't happen. We sold a pup, so we have the funds to go to my family reunion this weekend. Consequently, we spent most of the day getting things done ahead so being gone for the weekend won't put us very far behind when we get home Sunday.

I do have a couple questions though. I looked at the timing chain on both motors and now have a question about how to measure for chain stretch. Do I measure for extreme stretch, or ? By extreme stretch I mean, stretch the chain as far as possible outwards, then as far as possible inwards, and measure the difference? Or, use a straight edge between the two sprockets, push the chain inwards as far as possible, and then measure the maximum deflection?

Chain have more than 30K miles on it?
Yes: REPLACE IT!
No: Maybe Replace it.
These chains go on tight. They then stretch out quickly and the service limit is 0.8" by deflection from a side. You bump the timing at 30K miles to fix the new chain that stretched out. You are there it's best to just replace it.

The second question is about checking for main web cracks, mostly to see if my memory is correct. First, with the motor upside down and pan off, carefully clean each web, then clean again using brake cleaner to remove all traces of oil. Then leave upside down overnight and then check for any cracks that show oil traces on the metal surface.

Just wipe the oil off - do not clean. Oil will run down and highlight web cracks. No oil = no highlights.

When I pulled off the front cover on the 6.5 I was met with a big surprise. Somebody has apparently had the pan off before. On the front end where the pan and front cover meet the silicone gasket maker had been put on so heavy that it had squeezed out so far that the squeeze-out was almost touching the lower timing chain. I wonder if a chunk of silicone came off somewhere and caused my "lifter" knock problem? After we get back home I'll get my son or daughter to show me how to post pics.

Cut open the oil filter and see what's in it. If the silicone made it past the bypass and through the cooler... Not likely. Check the push rods and rockers for wear. If one was installed upside down the wear will be extreme and plain to see. Assuming it's a lifter - could be injector, bearing, wrist pin bushing...

Don

See notes above.

Even on my budget I don't reuse chains when I am looking at them. I change the entire set as the 1992 project is an example of what else can fail on the timing set.
 
O.K., I'm back home now. Yesterday and this morning I spent doing garden work that had to be done to keep the weeds from overtaking the good plants. I got a call from the guy rebuilding the transmission. It went well, except he had to replace the planetaries (?I think is what he said?) as the clearances were beyond specs. The trans was just beginning to exhibit slipping in the 3-4 shift, but nothing else that I knew of. I can pick it up Wednesday afternoon or Thursday.

This afternoon I stopped at two different auto machine shops in the Albany area. I'm not sure if there are any other machine shops in Lebanon or Corvallis. Both shops are very busy, but I did get prices. The guy I talked to at the second shop seemed to be familiar with the 6.2/6.5.

Tomorrow morning I will try to move both motors over from the gravel to a short concrete apron in front of the shop. The ceiling is too low to do much else except work with the motor on my engine stand, but I can utilize the apron and door area for that. Then I can start doing more detailed checking. The first order will be checking for main web cracks.

Here's what I do know already. I replaced the exhaust crossover about three years ago with a larger aftermarket one at the same time as a Diamond Eye 4 inch exhaust, both of which are still in good shape, so I can reuse them. Thanks for the offer of a crossover hookedup50, however I may need to consider your timing chain offer. The timing chain on the 6.2 has about 5/8ths inch of extreme stretch, while the 6.5 has about 3/8ths inch (marginal? possibly). The IP was not exhibiting any problems. The PMD has already been moved to the bumper area. The injectors were Bosch India that have only about 20K miles on them. The glows are Bosch Duraterm #80034, put in at the same time as the injectors. However, if I can find someone to check the pop pressure and spray pattern on the injectors that will be done.

I don't know about the rings yet Leroy, but if I can use standard size rings do you know if just second rings are available separately at a reasonable price? I'm definitely interested in gapless rings, but on my budget I'm not sure I can afford them. I won't know about the rockers/lifters until tomorrow, hopefully.

At any rate, tomorrow at this time I should know a little more, as long as the temps don't go absolutely crazy. The last few days have been cool, in the upper 70's and low 80's, with some rain on Sunday. Today was about 90, and tomorrow is supposed to start a hot stretch (for here) in the upper 90's and into the low 100's. All that I'm doing will be out in the sun, so we will see how long I can stand being out in the heat.

Don
 
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