6.5L Turbo Diesel Blazer Project

[Robyn]

Glad to see all the great progress.....

[More Power]

Glad to see all the great progress.....

Thanks Robyn...



I also did something during assembly that we've weighed the pros/cons about here in the forum before, regarding the 1997+ cooling system mods.

I couldn't locate a new double thermostat crossover housing - though I really didn't look too hard. But, I spent some time pondering the high-flow 130-gpm water pump, which this engine got during re-assembly, and how it would work with the single t-stat crossover. To make it work without the pressure buildup the GM cooling engineers said was possible, I installed the larger coolant bypass hose and fittings that run between the crossover and the top of the water pump, removed the bypass-blocking thermostat and then installed a non-bypass-blocking single hi-flow thermostat. That much, is the same operationally, when compared to the twin stat crossover/cooling system when the thermostat(s) are closed or only partially open.

The only negative to this arrangement is that the full benefit of high-capacity flow through the radiator will be reduced by a small amount when compared to the 1997+ systems when those twin-stats are fully open, but there shouldn't be any pressure buildup in the cooling system when compared to a double t-stat crossover. If this were a tow rig I'd have spent more time looking for a twin stat crossover, but this Blazer will likely not see much heavy towing... In any case, the cooling system should be an improvement over the original by simply moving more coolant through the block/heads more or less continuously (less likely to crack heads) just like the complete 1997+ cooling system. Jim

You can read more about the 1997+ hi-capacity cooling system here:
TheDieselPage.com - 6.5L Diesel Tech - Dual Thermostats. What’s the real story? - Updated November 2018

[Robyn]

Another little tid bit is to drill a 1/8" hole in the T STAT (In the plate portion)
This likely has zero effect on the water pump.

But it will allow the air to burp from the cooling system
during initial coolant fill.

Some stock Stats have a little burp valve (Little hole with a tiny valve) some don't....
Leaving the hole in the stat just assures there will not be an air lock.....

The bleeder on the housing is nice too.....The initial start will see a full cooling system without having to leave the Rad cap open during the first warm up cycle.

[More Power]

I think the new t-stat I installed had a formed notch that would function as an air-bleed for the system. The cooling system was pretty easy to get full, but we'll see how it looks after we start driving it.

One another subject: Injectors...



Seems diesel fuel injection vendors are transitioning away from the 6.2/6.5 injectors, which includes Kennedy. He may not be offering 6.5 injectors for much longer, if at all. I bought the above set from USDieselParts.com, a local to me vendor. About $60 each, but these are brand new injectors straight from Germany (update: made in India, see next post), so there is no core charge associated with their purchase. They don't come with copper washers or any other installation items, but all that is available from USDP as well. I bought one of their injector install kits a while back that includes an intake top piece gasket, injection pump flange gasket, 8 copper washers and a full set of hoses/plugs for the return lines - about $30 some bucks iirc.

USDP told me that they were no longer rebuilding these injectors. Combined with what JK said, I suspect the availability may not continue as we've always expected. So... if your 6.5 needs injectors, I'd not wait much longer. The cheap stuff off eBay will likely be available for some time yet, but who really knows about that stuff?

[arveetek]

Do your injectors state they are made in India? My "genuine" Bosch injectors have the same label as yours, shows they came from Germany, but also shows they are made in India:






Casey

[More Power]

Do your injectors state they are made in India? My "genuine" Bosch injectors have the same label as yours, shows they came from Germany, but also shows they are made in India:

Casey

You are right, the packaging does say "made in India" . I guess I stopped looking once I saw "Germany" on the packaging... Thanks for the catch.

What's interesting is that I removed the injectors from the "spare" engine I recently acquired so I could use them for the cores (didn't need them), and saw that the sooty side of the injectors looked like they were practically new - almost no carbon buildup on any of them. Made me wonder about the sequence of events that led to that engine being pulled. I need to spend some time looking at them...

[arveetek]

You are right, the packaging does say "made in India" . I guess I stopped looking once I saw "Germany" on the packaging... Thanks for the catch.

I ended up purchasing my injectors from John Faddis at Quadstar Tuning for $370 plus shipping for a set of 8. I am very happy with his service and prompt shipping. I also ordered quite a few other parts from him.

I tried going through Kennedy first (always my first place to shop), but like you, was unable to source them from John. I completely forgot about US Diesel Parts (I should have looked at TDP Vendor list). I was a bit hesitant to try a new source that had such a good price, but I have been very pleased with his service so far, and it appears I did, in fact, receive genuine Bosch injectors. They were completely sealed in plastic bags inside the Bosch boxes with the same plastic caps you pictured.

Casey

[More Power]

Thanks again to Greg and Robyn for the front driveshaft parts. Here's what the parts look like now. Had the pros shorten it a little bit to 31-1/4" between u-joints center-to-center, install new joints, clean/lube the slip joint, precision balance and then paint it. It looks like a new piece. Happy camper!

By the way, I sent this image to my daughter a bit ago. She immediately called back! She likes nice new looking parts too!

[Robyn]

Sweeeeeeeeeeeeeeeet.

Happy to have been able to help.

[DmaxMaverick]

Purdy!
My pleasure.

[trbankii]

Good to see it coming together!

[More Power]

Wish I knew how to get a 45 second video of the engine running (Apple MOV file) into a post... It's a little over 100M for some reason.

I finished the injector replacement this afternoon. In the end, it runs really well. No missing, no injector knock and no smoke - just the typical 6.5 rattle. Touching the alternator while it's idling shows it to be very smooth. I'll eventually get a TDC-Offset performed to make sure the timing is close. Sounds a little advanced now... just a little.

I had started it after replacing the 4 injectors on the driver's side. I didn't want all 8 airlocked... It started right up, and I ran it till it was as smooth as it was going to get. Apparently the leaking injector was on the passenger side, which produced a fuel knock and smoke.



The turbocharger needed to come off to make is easier for me to change the passenger side injectors. I couldn't get the injector heat shield off with the turbo in place. As usual for Murphy's law, the #8 injector was the one leaking fuel into the cylinder. The nozzle on #8 was wet when I removed it, whereas all the others were just sooty black.

After finishing the injector install I just cranked it without a prime, because I had run it after changing the other 4 injectors...

But now, it wouldn't start. So I primed it, then it would hit on the prime, then nothing. I removed the intake top, then primed each of the 8 cylinders. It would run on the prime, then stop. Did that a few times, till I replaced the NOS black PMD with a used spare PMD. It started right up and smoked a fair bit till the prime fuel was used up. Who would have guessed that NOS POS PMD would do that?

Next problem is the brakes... Pedal nearly goes to the floor. I'm guessing a master cylinder. The brake light on the dash came on a couple of weeks ago after I pressed the E-brake pedal. I haven't eliminated an e-brake switch yet...

[arveetek]

Who would have guessed that NOS POS PMD would do that?

NOS POS PMD... that made me chuckle!

Casey

[More Power]

One tool for the tool box IF YOU DON'T HAVE ONE

15mm Gear wrench ratcheting box open end with flex head...

You know, I bought my very first ratcheting wrenches a few weeks ago. That set had a 3/4" in the set, which would allow me to use it on my 6.5 injector socket in tight spaces. Turns out I didn't need it, but they are pretty sweet. I'll look for a set like you mentioned (includes a 15mm swivel head). I was gifted another rolling tool box a few weeks ago... Gotta have stuff to put into it now...

[2INSANE]

Thanks for sharing your daughters build! It looks nice and clean like it was factory. What is the part number for the non-bypass-blocking single hi-flow thermostat that you added to the single stat? I was actually surprised to read that you went with the single instead of the dual and didn’t add more upgrades to the motor. But as a normal daily driver, I understand the lack of need for them.

[Robyn]

I had scoffed at the ratcheting box end wrenches as being an answer to a question that was never asked.
I was Waaaaaaay WRONG ON THAT ONE...

I bought an SAE set as well as the METRIC set (Harbor Freight ) and have put them to the test many times.....Most jobs they sit in the drawer....but when you need one for a tight spot.....Yeah buddy.....they gitterdone.

I also make it a habit of buying the odd handfuls of wrenches at garage sales for a few $$ and tossing them in a drawer.

I have a bunch of odd looking stuff the we have crafted to get at nuts and bolts that were simply not doable with conventional wrenches.

Some of the creations look like they were hatchlings from your worst nightmare.

Saves having to hack up the good tools.

The Son inlaw has an 08 Dodge 6.7 and we needed an odd wrench.....it must be a special Cummins tool......Nothing would fit in the location and work.

Heated, bent, twisted and tweaked....Welded on a handle.....Nut came off... Patience was badly distorted in the process though ....

[More Power]

Thanks for sharing your daughters build! It looks nice and clean like it was factory. What is the part number for the non-bypass-blocking single hi-flow thermostat that you added to the single stat? I was actually surprised to read that you went with the single instead of the dual and didn’t add more upgrades to the motor. But as a normal daily driver, I understand the lack of need for them.

Sorry, I tossed the box. That t-stat was one I have had for a long time. I used it for demo-photo work back 20 years or so.
It looks like this one: https://static.summitracing.com/glob...-330-195_w.jpg

I used Robert Shaw t-stats in our performance 6.5 builds in the past. They are a high-flow design.

If this Blazer was being put together to tow, I would have installed the twin stat crossover, but it's not, so a compromise was made that shouldn't affect the engine. Daughter plans to use it to commute occasionally when the weather is snowy, camp occasionally in the summer, and carry a kayak on its roof rack occasionally. She has a car that gets 2x the fuel economy, so... This way it stays in the family.

[More Power]

I had scoffed at the ratcheting box end wrenches as being an answer to a question that was never asked.
I was Waaaaaaay WRONG ON THAT ONE...

I bought an SAE set as well as the METRIC set (Harbor Freight ) and have put them to the test many times.....Most jobs they sit in the drawer....but when you need one for a tight spot.....Yeah buddy.....they gitterdone... clip

I like having tools! A lot of my stuff is the Craftsman brand - going back 10-30+ years. I've found the quality of many of the Harbor Freight tools is quite good - easily comparable. I now have a bunch of their wrenches. However, I recently bought a HF metric tap/die set... Got it to refresh the fasteners for the 6.5 project. But the quality was so awful that it was unusable, so I made do with my smaller Craftsman set. I need to take my reading glasses with me when buying stuff.

[Robyn]

Taps and dies need to be made of "High speed steel" (Not meaning fast)
The high carbon steel stuff that most hardware stores and HF sell are junk.

High speed steel, cobalt and carbide are the real deal.
I have a few cobalt....a couple carbide taps....all the rest are high speed steel.


These cost a lot more than the hardware store high carbon stuff.

High speed is the standard for more industrial machining.....Get into aircraft or exotic metals....then comes cobalt and carbide tooling...$$$$$$$$$$$$$$$$$$$$$$$

A high carbon tap can possibly CLEAN UP a dirty thread....MAYBE....

I have had to dig broken ones out....SO I DO NOT USE THEM....

AVOID THE TiN (Titanium Nitride.....Gold colored)

These are simply TiN coated high carbon steel.....MORE JUNK
Same goes for TiN coated drill bits.......

High speed steel.....GOOD STUFF...OR COBALT if the going gets tough.....then beyond that comes carbide.....

HF screw drivers are junk....Same for the drills....band saw blades are junk too...

Their power tools are pretty decent.
Wrenches are good.

I bought an air compressor from HF after my 30 plus year old unit came apart one day...

It started sounding odd....By the time I got into the shop it was shedding pieces...BIG ONES...

[More Power]

Anyone know what that wire is for at the top of the rear hatch lift strut? It had apparently been broken off for quite some time. The driver's side strut has an identical broken wire, and there is a matching wire (not broken) on the opposite end (bottom end) of each strut. The rear wiper works just fine, and the electric rear gate unlatch works fine too.

There is a dash control for a rear defog, but the glass doesn't have the typical embedded heat element...

By the way, we installed the new front driveshaft on Sunday, then took it for a drive around our property in 4WD. Seems to work great! Just gotta get the brakes fixed (pedal goes almost to the floor and doesn't pump up)... will be getting a new master cylinder this week (an ACDelco unit from Amazon). Hope that's it.