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Major engine rebuild taking place

Well, I owe you an apology I guess....turns out reworking these heads are more expensive than I thought. The shop called me about my heads I dropped off, and mine are pretty much shot....it's going to take $650 to rebuild them, and that's even leaving some questionable cracks alone.

I'm going to drop off a second set of heads I have and see if they're any better. One problem with using the other heads is that they're '83 model heads with fine-thread injectors....that means I can't use my current coarse-thread injectors. There goes another for $150 to $200 for injectors. And if I install new injectors, the pump should really be refreshed.....

I'm going to talk to my uncle about a good, low-mileage n/a 6.5L he has in his '85 van. He told me a while back he wanted to sell it, so I think I might take him up on that offer.

The pistons I ordered haven't been made yet, so I'm going to hold off on those until I decided what route to take.

I may have a good 6.2L block to sell! It's already been bored .030" over and has new cam bearings installed...ready to go!;)

Casey
 
Update...

Here's what's happened since my last post:

My uncle wanted $2000 for his '86 van with a 6.5L n/a that was installed brand-new in '97. He has receipts showing that the engine cost $4800, plus labor. The engine only has around 30,000 miles (I think...I've slept since I've talked to him), but the rest of the van is starting to fall apart. I'm sure it's a good price, but I didn't want to spend that much and end up with a used, stock 6.5L. I'd rather have a highly customized 6.2L.

However, my uncle did have the old 6.2L out of the van, and it had thrown a rod, but had good heads. I bought the old engine for $50, so now I have three 6.2L's sitting in my shop!

The spare heads off my '83 engine were in better shape, but had too much rust. The shop was afraid they would leak at the exhaust manifolds. The heads off my uncle's '86 van turned out to be in pretty good shape, though. Still ended up costing me about $565 for the head work, including the labor on inspecting/cleaning the other two pair. The shop resurfaced the heads, did a valve job, installed new guide seals, and sleeved all the water passages between the valves.

So I'm now going to be using newer style heads with the fine-thread injectors. I ordered new 6.5L turbo injectors from Tim at accuratediesel.com. I also sent him my old injection pump and had him rebuild/upgrade it to 4911 specs. He's done with that, and I should have the pump and injectors back this week.

I also received the new custom-made, lower-compression, .030" over ceramic-coated pistons from the Diesel Depot.

Things were going along pretty well until about a week and a half ago. I had nearly all the parts together, and all the machine work finished. I started assembling the short block, and all was going well. Crank fit perfect, had perfect oil clearances on all the main bearings, camshaft fit great, and I installed the new pistons onto the original rods. Before fitting the pistons into the cylinders, I checked the top compression ring end gap and discovered that the end gap was .032", and that's .010" too large. The max. gap allowed, according to the specs, is .022". I knew something wasn't quite right. I went ahead and installed piston #1, and then I could see that the piston seemed awfully loose in the bore.

Well, to make a long story short, the machine shop bored my cylinders .004" too big. Instead of waiting for the .030" over pistons to arrive, they bored the block by adding .030" to the stock bore measurement of 3.980". This would have been fine, except that the 6.2L stock bore is actually closer to 3.976". So the shop screwed up. I know that .004" doesn't sound like much, but that translates into a ring end gap that's .010" too large, and a piston-to-bore clearance of .007", which is well over the recommended .0035". I'm sure this engine would have run okay, but if I had assembled it like this, I would have had a new engine that was already worn out!

I have since ordered new .040" over pistons (luckily the Diesel Depot is taking the .030" over pistons back in exchange for a small fee), and am waiting for them to arrive. This time, I will wait until the new pistons are in my hands, and then I will have the shop bore the block again to fit the new pistons. The shop has agreed to do this at no charge.

If I knew then what I know now, I would have waited for the .030" over pistons to arrive before boring the block, but I didn't know any better. You live and learn, eh?

So, that's where I'm at right now. Just waiting on the pistons. Soon as they get here, I can get the block bored again, and then start assembly, again!

One of these days!! :rolleyes:

Casey
 
I'd be a little affraid of any shop that did not require you to bring in the new pistons first :frown1: When I rebuilt my first motor I didn't know any better but I was glad when they made me order the pistons and bring them in first (also took the time to explain why). Made the assembly go perfect.
 
Things are still heading forward...just rather slowly.

As you may recall, I had to order new .040" over pistons due to the machine shop's mistake. Before milling new pistons, Benny Avant suggested that I install the .030" over pistons and see how far they were recessed into the block, to make sure that all the other calculations were correct, and to make sure my block decks were straight and true, not tapered.

After installing all 8 pistons onto the rods, and assembling the pistons into the block, I measured each piston at TDC to see where the top of the piston was in relation to the top of the deck. On a factory engine, the piston will actually protrude from the block about .005". After reducing the piston by a total of .020" (relocationg wrist pin by .010" and milling another .010" off the top of the piston), the pistons should now be recessed in the block about .015". Benny said it's not unusual for the decks of these GM diesels to taper as much as .005" from end to end. So, I could end up with a piston in #1 that was .015" in, and #7 could be .010" or .020" in.

So, using a straight edge and feeler guages, I put each piston at TDC and came up with the following measurements:

#1 .014" #2 .014"
#3 .015" #4 .015"
#5 .016" #6 .015"
#7 .020" #8 .015"

As you can see, they were all really close, except for #7. Benny said that GM did not maintain very accurate rod lengths, and that swapping rods can usually fix minor problems like this. I pulled a rod from one of my spare engines, swapped it into #7, and then took another measurement. This time, with the new rod, it measured .016". That's close enough. Benny said .002 to .003" is as far apart as you want. That will keep the compression ratio equal on all cylinders.

Benny also said that .009" to .010" equals one compression point, so that means if the cylinders are way off, one cylinder could have 21:1 compression, and the one next to it could have 20:1 compression.

My engine should end up with around 19.75:1 compression.

So, with all these numbers reported to Benny, he declared it satisfactory and is going ahead and milling the new .040" over pistons to the original specs I gave him. Hopefully I will have the new pistons by the end of the week, so I can get the machine work finsihed up, and actually start assembling it for good.

I also received my rebuilt injection pump and injectors today, courtesy of Tim Wagner at accuratediesel.com. I ordered the 4911 upgrade and 6.5L turbo injectors. Can't wait to install them!

Casey
 
casey is he just milling the tops straight off or is he dishing them out? Is he recoating them?
 
Rugger,

He ordered pistons with the wrist pin moved up towards the top by .010", then he milled another .010" off the top of the pistons, then he ceramic-coated the tops.

Casey
 
I got the new pistons last week, and the shop machined the block to fit the new pistons. I had them bore/hone the cylinders to have a .0035" piston-to-bore clearance on cylinders 1 through 6, and .0040" on 7 and 8.

I started engine assembly over the weekend, and I'm sailing right along!

By the end of Saturday night, I had most of the longblock assembled, just short of the drivetrain:

http://community.webshots.com/photo/286393940/341897559wxPOIn

As of lunch time today, this is where I'm at:

http://community.webshots.com/photo/286393940/341986527HPXCnb

You can see the rest of my engine assembly pictures, including pics of the stud girdle kit and timing gears, starting on page three of my engine rebuild album.

Casey
 
Hi Casey. Welcome back. On the subject of blocks, I have a Goodwrench 6.2 that has red paint on it, supposed to be an '82. What other markings should I look for to confirm that it is the preferred '82 block? Wonder if any
red blocks were used in '83s?

Peninsular Hi Flow Water Pump: do these require a serpentine set up?
I bought one a while back, not installed. I'm running V belts, wonder if
it runs reverse rotation to the V belt pump?

Rings: I'm going to try some TotalSeal rings. Supposed to help.

Pistons: I bought some 30 over SilvoLight pistons and sent them in
for coating. Skirts look black like a teflon fry pan, and the top is
a grey color. Stock CR.

We need to compile a build-up wish list and post it as a permanent thread.
 
Steve,

As far as I know, only '82 engines were painted red. My '82 block has a date stamped on the block, right beneath the casting number on the driver's side right behind the head. Mine says 3-2-81. I also have an '83 block that has a date stamped in the same place of 5-5-82. It was painted black, no trace of red.

Peninsular makes both a high-flow v-belt and serpentine belt pump. You'll have to check the pump number with Peninsular to see which one you have. If your ordered it for the 6.2L, it ought to be a v-belt pump. You're correct in that the serpentine pumps run in reverse compared to the v-belt pumps.

I did some more work on the engine. I got the injection lines and return lines installed yesterday afternoon. I spent some time cleaning up the injection lines so that they're nice and shiny, and I also spent some time installing new return lines with the little spring clips to hold them in place. I hate those little clips, but I hate dripping return lines even more. Perhaps I won't have to mess with them for quite some time now.

http://community.webshots.com/photo/286393940/342644394dZGVzj

I also got the water pump installed. I'm getting really close to getting the engine ready to install, but now I have to go back to work. I gotta make some money! I'll have to work on this project in the evenings again. I hope to start installing the engine by Thursday.

Casey
 
My '82 and '83 blocks, here's what I found:
'82 red; '83 black
casting number 14022660 same
"GM 6.2L D" same
'82 block date, none; '83 block date "9-7-82"

I wonder if the cast iron matl is same in both blocks.

I anticipate that I have made the exact same mistake with piston fit.
Bored block 30 over before I had the pistons. My '82 block is unbored so
I'll bore it for the 30 over pistons and have the '83 block as a spare.
 
The project is completed! :D

Finally! This project has dragged out way too long for my tastes. I pulled the engine at the end of February in the cold weather, and now it's hot and just a few days away from June! Oh well! It's all behind me now!

I got the engine assembled and installed over the past couple of weeks, and fully running on Monday night. I made a couple of mistakes that set me a back a few days, though.

My first mistake was that I managed to bolt the flexplate (flywheel) on backwards, and didn't notice until the engine and tranny were bolted up together in the truck. I tried bolting the torque convertor to the engine and noticed it wasn't going together correctly. Doh! I had to completely remove the tranny to R & R the flexplate. Not too bad, only took me 2.5 hours to do the whole job.

The other mistake was worse. I got the engine started and discovered that I had very little oil pressure, and that exhaust was popping back through the intake. I figured the two problems were related, and decided that the exhaust popping was due to lifters not getting pumped up due to low oil pressure. After some digging around and investigating, I found out that I had left the two lifter oil galley plugs out of the front the engine! This pretty much let all the oil being pumped up through the block get dumped straight back into the oil pan! Doh! I had to remove the water pump, front cover, and timing gears to get to the oil galley holes next to the camshaft. Just took a couple of minutes to install a couple of freeze plugs in the holes, but it took an entire day's worth of work to tear down and reassemble the engine. After starting the engine a second time, I had great oil pressure and no exhaust popping through the intake. I was quite frustrated at the time, but that's all behind me now. I just don't know how I skipped that step as careful as I was.

I've been driving the truck for about two days now. Runs like a champ!

Before I pulled the motor, the engine was starting okay in the morning, but the smoke screen it layed down was absolutely ridiculous! The white/blue smoke would completely envelope the truck, and it would continue smoking some even when fully warmed up.

This morning I started it up, jumped out of the truck to look at the tailpipe, and I could detect no smoke whatsoever! Granted, the ambient temperature is warmer, but still! I'm using the exact same 60G glow plugs and plug controller that I had with the old engine. They were in good shape, so I didn't replace them. I just let the plugs glow for about 10 seconds, hit the key, and bam! She's running in the first revolution of the crank with no smoke out the pipe.

I do have black smoke, though. But only when I mash on the go pedal! From a standing start I can mash the pedal and a large cloud of black smoke comes pouring out, but just until the turbo spools up, and then it's gone! And so is the truck! Man, this thing will push you back into the seat, that's for sure. I thought it was running great before, but I can't wait to get a load on this engine and see how she pulls. I didn't have any black smoke before the rebuild, and I had turned the pump up quite a bit.

I can't hear the timing gear drive set. I've read that some people think they're noisy, but I can't hear it at all unless I take the oil fill cap off, and then there's a slight gear noise.

The engine seems to be running a bit hotter on the water temp, but that's normal for a new engine. I can't detect any real changes on EGT or boost as yet. Still hitting around 14 psi, but I haven't run it really hard yet.

I'm so glad to be getting past this rebuild stage and actually having a truck I can drive again! I tell you what, this truck has come so far from it's original C code naturally aspirated days, it's not even funny. It's no longer a gutless fuel pincher, that's for sure. I just hope my mpg doesn't drop TOO much!

Sorry for the long post, but I just wanted to give ya'll and update!

Casey
 
Congrates. Happiness is rebuilding your own motor and getting to drive it knowing you built the sucker.

Your posts have inspired me to start a 6.5 rebuild with a turbo upgrade. Picked up a standard bore 6.5 block 2 weeks ago. Gonna piece it together and hopefuilly end up with something similar to what your running.

Cheers to having your truck running. :waytogo: :waytogo: :waytogo:
 
Awesome deal Casey! Congrats, and don't beat yourself up on the small mistakes you made. I can't imagine anyone ever gets it all 100% right the first time...

Rene
 
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