Poor Boy Special 6.5 Refresh

[bowtiebutler956]

I started a thread in the 6.5 performance section because I had a question about the use of an ATT on my 6.5, and I continued to just post updates in that thread rather than starting a new thread in this section on the engine. Anyway, I recently picked up a 93 K2500 that was a basket case. The pass side head was off the engine, and missing, along with other parts. After pulling the engine, and inspecting it, I found one 3/4in long crack in one of the main webs. Not having any extra cash to buy a set of heads for this engine, I decided to pull the 6.5 N/A out of my 96 G30 van, and use it in the truck, as it is a good running diesel. After pulling the engine, I removed the pan to find 2 cracks in the mains on this block, and maybe more once I do a closer inspection. :???::mad2: Its really quite frustrating that most of these 6.5 blocks have cracks. In the future, I would like to buy one of the updated pull outs from Ted's, but thats not an option right now.
So, here is my current game plan. I've ordered a set of Mahle rings, and some new rod bearing that will be going in one of these blocks. (probably the 599 from the truck as it only has one crack in the block). Its been recommended by others not to replace the main bearings if they look good, as the factory custom fit them to each engine. It has also been suggested to not even touch the main caps to prevent further cracks, but I don't know how I would be able to clean the block properly after honing the cylinders, if I don't remove the crankshaft. :???: Let me know what you think.
I can't afford to dump a bunch of money in this engine, as the condition of the rest of the truck is unknown. It would stink to put a bunch of money into it, just to find out I'm going to have to rebuild the transmission, etc... That being said, I have already bought new injectors, glow plugs, rings, rod bearings, full gasket set, and seals, as well as a new Diamond Eye down pipe from Leroy, as there is no way I'm putting the OE down pipe back on that looks like its been run over by a truck several times! I've also made a homemade turbo master for it, as well as drilling, and tapping the exhaust manifold for an EGT gauge. I've been cleaning, and repainting parts, and I'm leaning towards painting the engine Red. Here are some pics. Thanks

Matt

 

[bowtiebutler956]

I forgot to mention that it will get a new harmonic balancer, head bolts, as well as a later model HO water pump. I've already installed a 180 high flow thermostat in the water crossover. I'm still undecided whether to replace the oil pump. Here is a pic of the turbo master. Thanks

Matt

 

[great white]

Probably not what you want to hear, but I wouldn't put on thin dime in to a block with cracked main webs.

Throwing your money away.

If pressed for cash and the cracks were in the main cap bolt holes, I would take a risk on a lock n stitch insert. But it has to meet very specific criteria to be a candidate....

Good luck.

 

[bowtiebutler956]

Probably not what you want to hear, but I wouldn't put on thin dime in to a block with cracked main webs.

Throwing your money away.

If pressed for cash and the cracks were in the main cap bolt holes, I would take a risk on a lock n stitch insert. But it has to meet very specific criteria to be a candidate....

Good luck.

I certainly hear what your saying, but how many 6.5's do you think are running down the road today without cracks in the mains? Or maybe I should say ones that haven't had the updated engines installed. The only parts that I'm buying for this engine that can't be transferred to another 6.5 are the gaskets, rings, and rod bearings. So, worst case, I'm out $225. I'm a bit of a perfectionist, so the cracks in these blocks really bug me, but with money being tight, its either do it this way, or don't do it at all. I figure it will last awhile, and in the meantime, I can work on saving $3000 for an updated, and improved military take out 6.5. With the new GEP engines running nearly $6500, lets face it, a 93 K2500 in near mint shape isn't worth the initial cost of the engine.
While I do like the look of those lock and stitch inserts, I can't justify the added machine shop cost, when after fixing the one outer bolt hole, it may develop a crack under another one 1000 miles down the road. My ultimate goal is to have an updated block 6.5, but for now, I'll see how long it lasts. Thanks

Matt

 

[WarWagon]

"It has also been suggested to not even touch the main caps to prevent further cracks, but I don't know how I would be able to clean the block properly after honing the cylinders, if I don't remove the crankshaft"

On a diesel you are just breaking the glaze. "Properly" (and sanity was already gone long ago) went out the window with re-using a cracked main block. What I did years ago: Oil the bearings with crank/cam in place. Cover as much as possible below the cylinder with an old pillowcase or towel. Break the glaze. Turn engine over on the stand and run the cleaning hose from the bottom to the top. Re-oil everything. Theory is the stress has relived itself via the crack and re-torquing the mains bolts will add new stress.


Boyce Equipment has low mile 6.2 engines for $1500 plus shipping. They test them before shipping and have a short warranty. You could ask them to pull the pan and check the mains for cracks. Comes with a 6.2 IP you can also use. Re-ring it, use the 6.2 heads, finesse the 6.5 injectors to fit and you won't even notice with the POS factory turbo. Bigger turbo's and you will need to enlarge the precups. Possible 6.2 and 6.5 precups are a different diameter. The 6.5 NA van heads are possibly what I am running with the ATT on my 1993.

 

[JayTheCPA]

. . . but how many 6.5's do you think are running down the road today without cracks in the mains?

Tough to tell, and even more difficult to tell how long they will last. Mine went from Hero at 155K miles to Zero at 160K miles. Even sounded good and got 19 mpg despite it was shot. Fortunately an oil analysis caught a coolant contamination issue so I could repair on my terms.

I'd go with WW on this as he definitely learned from experience.

. . . lets face it, a 93 K2500 in near mint shape isn't worth the initial cost of the engine.

At this point, cost of the engine compared to value of the truck has little meaning. Question comes down to: how much is it's future worth?

 

[bowtiebutler956]

"It has also been suggested to not even touch the main caps to prevent further cracks, but I don't know how I would be able to clean the block properly after honing the cylinders, if I don't remove the crankshaft"

On a diesel you are just breaking the glaze. "Properly" (and sanity was already gone long ago) went out the window with re-using a cracked main block. What I did years ago: Oil the bearings with crank/cam in place. Cover as much as possible below the cylinder with an old pillowcase or towel. Break the glaze. Turn engine over on the stand and run the cleaning hose from the bottom to the top. Re-oil everything. Theory is the stress has relived itself via the crack and re-torquing the mains bolts will add new stress.


Boyce Equipment has low mile 6.2 engines for $1500 plus shipping. They test them before shipping and have a short warranty. You could ask them to pull the pan and check the mains for cracks. Comes with a 6.2 IP you can also use. Re-ring it, use the 6.2 heads, finesse the 6.5 injectors to fit and you won't even notice with the POS factory turbo. Bigger turbo's and you will need to enlarge the precups. Possible 6.2 and 6.5 precups are a different diameter. The 6.5 NA van heads are possibly what I am running with the ATT on my 1993.

Thanks WarWagon, I will follow your advice, and won't touch the main bolts. I realize this engine is going to be a bit of a crap shoot, but its really about all I can do right now. This thread might have been better titled Poor Boy Gamble, than Poor Boy Special.:hihi:

Matt

 

[bowtiebutler956]

Tough to tell, and even more difficult to tell how long they will last. Mine went from Hero at 155K miles to Zero at 160K miles. Even sounded good and got 19 mpg despite it was shot. Fortunately an oil analysis caught a coolant contamination issue so I could repair on my terms.

I'd go with WW on this as he definitely learned from experience.




At this point, cost of the engine compared to value of the truck has little meaning. Question comes down to: how much is it's future worth?

My first experience with a 6.5TD was a 93 K3500 that I got about 15 years ago. Got it with just a little over 100k from the original owner. When I got rid of it, it had just over 300k on it, and I had never opened the engine up! Granted, it was getting compression in the cooling system, which is why I finally thew in the towel, but it had the right to at 300k! I would have fixed it, except the rest of the truck was just slap wore out. Its really amazing to me that an engine with so many design flaws can run the kind of miles that so many of these 6.5's have. With 150k on this truck, I'm hoping this old cracked 6.5 can hang in there a while longer.:smile5:

Matt

 

[bowtiebutler956]

Made some progress today. I was hoping to have the short block assembled, but I didn't quite make it that far. I tried to use rags while honing the cylinder to cover the crank to keep the grit from getting in places it shouldn't be, so that I wouldn't have to remove the crank, but its a really messy job. So, I ended up pulling the crank out so I could get it cleaned up good. WarWagon, I really did try, but I kept envisioning grit running thru my oil tearing up the bearings. No doubt, I've caused more future cracks, but I really felt like I had to clean the block up better. The main bearings looked decent, but the cam bearings looked amazing. After using bottle brushes, solvent, and compressed air to clean out all the oil passages, I used some Lubriplate assembly lube on the cam, and crank bearings before reassembling. I cleaned out all the piston ring land, and installed the new rings on them, as well as the rod bearings. I'll try to get the pistons back in their holes tomorrow. Here are a few pics. Thanks

Matt

 

[Jorge6.5]

I'm not sure if this was posted already but you should have your injectors pop tested before install.

 

[Burning oil]

Looking good. Im building an engine for mine also.
What a diff in the DP's!!

PS. I have a piston ring compressor I'd loan you for a deposit and shipping cost.

 

[bowtiebutler956]

I'm not sure if this was posted already but you should have your injectors pop tested before install.

I agree with you, but I don't have the extra cash at the moment. Plus the rest of this engine is a bit of a gamble, so these injectors will fit right in. :hihi:

Looking good. Im building an engine for mine also.
What a diff in the DP's!!

PS. I have a piston ring compressor I'd loan you for a deposit and shipping cost.

I've been following your engine build Leroy, and its going to be a much better 6.5 than mine is! Not to mention great looking, even with the Ford blue oil pan. :smilewinkgrin: I'm going to paint mine red, but its just because I have a gallon of red on the shelf.
Its a night, and day difference in the down pipe! I still can't believe GM even made a DP like that! Buy the way, thanks for the great deal on the down pipe!:thumbsup:
I appreciate the offer on the ring compressor, but I have large assortment of piston ring compressors.

I put the pistons in this morning, and I could have done more, but I'm going to spend the rest of the day with my kids. Here are a couple pics of the pistons in their holes. Thanks

Matt

 

[WarWagon]

I envision the crank going through the oil pan on mine all the time. So grit in the oil from clean up is the additional risk I took. It has like 30K additional miles since I dropped it back in. I just remind myself to be prepared for an engine failure: You get 1 use (2 if your bad luck ends just after engine failure) of the brake on hydro-booster reserve so after pressing them stay on them. Corners are to be taken slower in case the engine lets go in one and I loose PS. (Excitement is: It makes you sore the next day to crank over the wheel more without the engine in a turn esp in a POS FWD with a dead engine drag kicking the wheel back.)

I would be curious if the crack length grew after re-torquing the mains.

 

[bowtiebutler956]

I envision the crank going through the oil pan on mine all the time. So grit in the oil from clean up is the additional risk I took. It has like 30K additional miles since I dropped it back in. I just remind myself to be prepared for an engine failure: You get 1 use (2 if your bad luck ends just after engine failure) of the brake on hydro-booster reserve so after pressing them stay on them. Corners are to be taken slower in case the engine lets go in one and I loose PS. (Excitement is: It makes you sore the next day to crank over the wheel more without the engine in a turn esp in a POS FWD with a dead engine drag kicking the wheel back.)

I would be curious if the crack length grew after re-torquing the mains.

You just had to say that didn't you. Now I'm going to be envisioning my crank going thru the pan while driving around! :rofl: I've lost the serp belt on my G30 (hydroboost) before, so I know what your talking about with the brakes, and steering.
I looked at the crack right after torquing, and it was the same, but I'll check it again tomorrow now that is had a couple days to settle. I'll post pics. Thanks

Matt

 

[bowtiebutler956]

I didn't get much done on the 6.5 today, but I did find the time to tear one of the heads apart. I cleaned it, lapped the valves, and installed the new valve seals that came with the gasket kit. All the valve seats were clean, and just a brief lapping with the fine compound, and they were good. Although the valve contact surface is wider than I would like it to be, but they will seal fine.
WarWagon, I forgot to take my camera with me today, so all I had was my phone, and no matter how hard I tried, I couldn't make it focus on the crank in the main cap. The crack has not gotten any longer, and is still right at 3/4 long. I'll take my camera with me tomorrow. Thanks

Matt

 

[WarWagon]

The engine failing in the middle of nowhere is not nearly as entertaining as blowing the turbo boot off at 24 PSI on the dyno during dyno days. You would have thought by the way everyone jumped out of their skin that the 6.5's reputation for blowing up... By the sound I thought I blew a radiator hose.

Now if video was involved on the dyno a crack failure would take a good 'seasoned' camera operator to stay put and keep filming. :leaving:

 

[bowtiebutler956]

Its not very often I can find the time to spend a whole day working on one of my personal projects, but I did today. :agreed: I decided not to use a rattle can to paint this engine, as I had a gallon of IH Red that I really liked the color of. I used hardener in the paint as well, so it should be very durable and resistant to oil, fuel, etc.. I used silicon on the valve covers, and oil pan. I used gaskets on the rest. I put a new timing chain in it. Just the chain, not the gears. Its nice, and tight now. I still have to buy the new HB, and water pump. An OE water pump for a 93 is about $55 at the auto parts, but the newer HO one for the 97-98 models is almost $100. :mad2: I'm going to get the HO pump, but I'm still whining about the cost! :rolleyes5:

Here are a bunch of pictures from today. The intake manifold is just sitting on the engine. I'm pleased with the way it turned out. Thanks

Matt

 

[bowtiebutler956]

WarWagon, I did get a picture of the crack this morning before I put the pan on it. Its still 3/4 long, and looks the same. here is a pic.

Matt

 

[NVW]

Engine looks good:thumbsup:

I was talking to the guy who does my sandblasting about hardener in paint, he said paint allowed to cure for a month will be harder without the use of hardener in the paint. He does a lot of oilfield painting.

 

[bowtiebutler956]

Well NVW, I doubt I have anywhere near the experience your friend has painting. I'm just going from my own experience. I have a thing for old american iron. I collect, and restore old farm tractors, garden tractors, hit n miss engines, as well as old vintage Briggs engines, and I started using hardener in my paint about 2 years ago, and noticed an immediate difference. The paint definitely had a better shine, and seamed much harder, and durable. When I get oil or gas on the paint, its not as easily affected, or dulled. I have noticed that if the paint get hit hard by something, it tends to chip when it has hardener. Overall though, the pros seem to outweigh the cons to me. Here are a few of my recent projects. The little bitty tractor (1952 Bantam), and the vintage mini bike are projects I did with my two youngest sons. My oldest son already has his own truck. They grow up so fast! Thanks

Matt