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I'm back, and survived an Optimizer 6500 rebuild. The TerraShuttle is alive and well!

Sentinelist

Active Member
Messages
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Location
North Texas
I just completed the Optimizer 6500 Navistar rebuild process from a military take-out. I loved the idea of the P400 but once I realized lightly-used Optimizers were within much greater reach financially - initially - I went that route. Six months later from that decision, let's cut to the chase (also, hey guys, hope all is well):

$2850 - Optimizer 6500 longblock
This was delivered freight to a diesel shop from tedstrucks.com in AL, purchased off eBay, motor has 10-40k on it from a HMMWV. Sweet deal! Nice outfit too with good folks and support- recommended.
$1250 - Shopping spree with LeroyDiesel.com and RockAuto.com
This was to purchase lots of 'hey, while we're in there' parts, namely: ARP studs, gapless ring set, BOSCH injectors and glow plugs, GM oil and water pumps, cam bearings, various gaskets, belts, hoses, and such. I may detail out in my thread shortly when I get home in front of the list. Half of this was preventative maintenance parts that I had no idea when the last time they were replaced (injectors), but half were parts that would be needed regardless (head gaskets). Thanks to a clearance deal at RockAuto, this also gave me a few extra parts for the shelf like a couple oil filters and hoses. Also thanks to you guys for guidance on this step earlier this summer!
$120 - Tow truck to the diesel shop
Unexpected expense, as they almost always are. The last time the truck started, it ran, but sounded like it had thrown a rod (hence the motor swap plan, and at 280k I couldn't trust it on anymore long trips with my family at any rate), but it moved. My plan was to crank it back up and limp it to the shop about 20 mi. away. No dice. Even after replacing the batteries, under warranty thankfully, it still wouldn't turn over, and I probably had a bad starter. Eff it. Called the tow truck, will let the shop deal with that when the time comes. Some poor little Izuzu NPR flatbed barely took the truck- it was smaller than mine.
$120 - Precup machine work
I had the diesel shop knock the precups out of the heads and I then shipped them to one of our contacts on here (whose name escapes me now as time has elapsed) in Detroit. He has access to the machine at his work to do this job but was backed up and unable to complete this for at least a month, but I finally got them back and they looked outstanding- went from the oval to more of the diamond aperture for improved fuel flow in the pre-combustion chambers (indirect injection, IDI) to match the improved output of the Optimizer 6500 with the ATT, etc.
$600 - Machine shop work
Once the diesel shop opened up the Optimizer, they said they didn't have the tool to do the cam bearings, but a machine shop the next block over knew how to do them. The motor was forklifted over, where they found some grime in block and said it should be cleaned out. The cams and pistons were also polished while they were in there fitting in the gapless ring set and the motor was returned back to the diesel shop after a couple weeks.
$3000 - Diesel shop work, transplant
After an initial estimate of $1000 to do the swap, the diesel shop I used ended up charging nearly 3x that amount due to the unforeseen challenges, having to strip down the motor a couple times after catching something, and rebuilding it again after the machine shop shipped it back to them disassembled, right after he delivered it to them already assembled. This was probably the greatest unforeseen expense of the whole project. An annoyance for sure, as they didn't communicate well, I had to beg for updates every few days, but by the end I had given up and finally had a working truck ready to be picked up so I lost the energy to care anymore. I was just happy to have it back so I can put it to work on the backlog of tasks I had lined up for it. Also, they got it running without any problem- no idea why it didn't for me with good power before it left my place.
$350 - Afterparty catchup maintenance
This includes the initial oil change that was done 60 mi. after picking up the truck from the diesel shop to dump oil that may have metal shavings in it from the rebuild and initial runtime, which was basically the trip home and a couple errands, a second oil change done 250 mi. after that (a week later) for similar reasons, a horn repair after it failed a safety inspection, the safety inspection, and re-registering it with the state after it had been off the grid for the past 18 months. And replacing blown 12V power point in the cabin. There are several other items to attend to, but that can wait over the next few months- the truck is running and has basically been my daily driver since Thanksgiving week.

Not counted- the basically new A-Team Turbo, Fluid Damper, Diamond Eye exhaust, AutoZone Platinum AGM batteries and AutoZone Gold alternator I had waiting to swap over, and all other ancillaries not mentioned that were carried over from the original mill, like the DB2 IP.

Summary
So, my tally sits at $8290 all-in after 6 months of effort, planning, and much waiting. This is compared to $7300 for a brand new P400 from LeroyDiesel.com, say $200 freight, and another $1500 for the swap at your trusted diesel shop (or FREE if you can do this yourself!) IF all your current ancillaries are good (unlikely- plan on a similar parts spree like I took to save yourself the grief later). And probably done in less than 60-days of downtime from sending over payment for the P400. I still came out ahead, but not by much. If I had to do it all over again, I would be weighing the P400 route very carefully, and likely would have gone that route instead, and had a truck online and working around my ranch much sooner. As such, I may have a louder motor with a few miles on it already, but the shop said it looked practically brand new as well to them with zero wear. So I can't say I have any real regrets except the time lost, and the several hundred more I could have put in over the top to give me the everlasting P400 instead. I'm just happy I have a motor that should be generally dead-nuts reliable now for many, many years to come, and a great truck that I can once again drive. Because picking up hay with your wife's nice Suburban sucks. But I'm overall happy and have put 1000 mi. on the truck since I got it back. Loving it!
 
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I'll edit the photos tonight if they're not showing up here...
 
WarWagon- good question! I probably should have expounded on that equally. It runs great, cranks right up when it isn't cold out. Notably stronger and a touch louder than stock, and feels a bit beefier. I haven't 'gunned it' to see if I can feel a lot more power yet as I'm still breaking it in, but I can feel it's there. I'm draining a fuel tank down today almost to empty to get a MPG estimate, but it looks like at least 15mpg city with a lot of long stretches at 50mph, so a little mixed. I'm pretty sure this thing will do 600 mi. to a tank on the highway, so 17.6+mpg highway. I'm hoping that improves a couple ticks each with the break-in period? I'm about 1k into what I think Leroy said should be a 5k mi. duration. Still, not bad. And near as makes no difference, not much worse than the other few modern V8 (gas) vehicles in my stable.

Jay- thanks, the K47 is next on my list. Hoping to slap one of those on there in the next month or so.

Tanner- me too! But not until the break-in period is cleared. I've been careful to keep this thing away from redline and have been easy off the line since I got it back. I didn't check the alternator pullies, but I didn't swap the core- the old one was still pulling a max of 12V, and for ten bucks, is a usable emergency spare, so I kept it. I'll compare at next chance. If anyone has any other guidance on the break-in period for everything I've done to this motor, please advise!
 
Stomp it!!! You need the rings to seat in esp the 2nd ring. Vary the RPM and load, but, you need a few full power excursions to seat the rings fully. - Just not extended time at full power.

I had a 30K mile rebuilt by the military take out engine. It never fully seated the 2nd rings in the engine from light use it had before I got it. Even after I gave it extended 30K of full power trailer pulls up grades 1/2 the ring face never had the break in coating worn off. Gapless rings and some abuse has zero blowby at 30K miles after install now.
 
awesome looking truck, in my favorite color too! :)

Curious, what was the reason behind the cam bearing replacement?

Like said above, get a K47 on that puppy and you should be good to go!

What route did you take on the cooling system?
 
Stomp it!!! You need the rings to seat in esp the 2nd ring. Vary the RPM and load, but, you need a few full power excursions to seat the rings fully.

X2! I ran mine at 75% power (not throttle position, but power requested) as much as possible. Also looked for opportunities to apply power uphill, then drop it in 3'rd on the downside (at a speed with the TCC locked) to force an alternating heating / cooling cycle on the pistons. Getting a good heating / cooling cycle is more of a challenge with the 4L80E.
 
That makes sense but seems counter to any typical break-in advice! Is my situation different because of the gapless rings? After 1k mi. since the rebuild now, it's safe to floor it for this purpose? Double-check the dollar figures posted above if you're not sure! ;)

On the cam bearings- just 'cause. Another preventative measure while the engine was readily accessible. The objective was to eliminate/rework/refurb/replace as many points of failure as possible to better ensure durability. At a snap notice, I want to haul the camper, my family, and gear up Pike's Peak. Not that I ever would, and the likely event would probably be camping in a remote spot off a logging road in the Ozarks, but that's the thought I'm building the rig around. Not sure if I mentioned, I also had the main bearings and rods replaced by the machine shop as they showed just enough wear to go ahead and replace while exposed.

As far as cooling goes, I already have the Duramax fan which is a plus, and the ATT should also help matters greatly from what I understand. Beyond that, nothing really- suggestions welcome. Afterall, I do live in Texas and this truck needs to be dependable.

The next big project for it in a year or two will be reworking the suspension. I'm going to look at a very heavy-duty 6" lift (unsure of yet), modestly larger tires and a wider stance for more off-road capability and stability with the camper on.
 
No different for Gapless rings - just need some full power to seat and varied RPM and power to 'oil' the rings. You are safe after 1000 miles to open it up for sure. Then to be safe/extreme/overkill follow the varied throttle and speed with full load like when you put the camper on for 500 miles.

Cooling: The Low temp Kennedy Diesel fan clutch is a favorite of mine and I run summer 180 and winter (all two weeks of it) 190 T-stats.
 
The GM part number 88894035 water pump that takes the spin-on clutch is the best pump. Get either the 99.5-00 6.5L clutch (factory clutch to that pump, order for a 00) or some say a LB7 duramax fan clutch will thread right on, but IIRC the 6.5L clutch will kick in sooner. your duramax fan should mate to either clutchs no issue.
 
I am a firm believer in breaking a diesel in the way it will be driven, if you baby one too much during break in it will not like it... Break it in hard and it will last.... You don't see big trucks being babied on the first few loads....
 
I'm almost the same as my South Carolina friend on that. Drive a little softer than normal until first oil change. After that, drive it like normal.

Maintained rpm a long time slows the rings seating, but that's no usually a concearn on big rigs. They usually max out load capacity enough every time they get a new load it will get a work out. LTL runs don't pay for new trucks well, so it will get worked quickly.

Ya don't wait an hour in a race engine either, that's a death nail.
 
Pretty sure he has the 2000 water pump? I think I remember selling it to him?

Would also recommend a CS144 alt when you can.
 
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