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Back from the brink...help me locate and build my next 6.5!

Focus on durability as there is not much in the way of kick-in-the pants gains without sacrificing durability.

Agree with the comment to not use marine injectors. From experience, they gained me nothing other than extra belching at start-up. OE injectors were noticeably more responsive to throttle inputs than the marines. Check with Leroy to see if he has a set of OE's. My vote is sell the marines to somebody whom thinks they are better than they really are.

Toward the parts list, consider a bypass filter. Or better yet a relocation kit with the dual filters.

And consider swapping out the Stanadyne FSD (it is a PMD when mounted to the IP) with a Flight Systems from Leroy. Got another subtle improvement in throttle response when I did this swap too.

When the time comes, a tune will play a huge role in the truck's overall behavior. And, the decision on turbo will make a difference in which tuner to work with.

Oh, and the IP . . . I developed an allergy to reman / rehab'd IP's. New or nothing. I know that some have had good results with reman IP's, but I did not.

If you can find a P-400, it is a tad more quiet than the other variants and supposedly a little more robust. But nothing is really going to make that motor very quiet aside from either going deaf, or a quality stereo system ;)
I've been mounting my bypass filters under the hood. Either near the battery box or on top of the left / drivers inner fender. I made a bracket, so i could pull the whole FS2500 and then change the element

I install a T in the return line from the engine oil cooler to feed the bypass filter and return to the engine oil fil neck.

I weld a nipple - pointed slightly down - into the fill neck. If you put them in straight or worse yet pointing slightly up, oil will splash out if you remove the fill cap with the engine running
 
Yea, after my experience with them and after a more thorough investigation, I won't trust anything coming from US Engine.

Would love to go with the P400! Would have jumped on it a few years back, had I known or been in a position to do so. But the going price seems to be about $9100, when/if you can find one. I can't justify that for my needs.

Great post Will! Good info, as always.
 
Hayden 2886 Fan Clutch... Return it and get a Kennedy Diesel low temp fan clutch. Rumor: Everyone followed GM and raised the turn on temp of the fan due to noise complaints. KD is said to use the square body style temps or IMO his own set point. Fact: the aerodynamic airflow of this body style reduces the airflow through the radiator stack vs. the older square body. Fact: getting the rings hot takes the temper out of them resulting in blowby. 210 ECT is considered the redline on this engine.

Your ordered the KD low temp fan clutch yet? Hayden's slightly lower setpoint I read about somewhere and likely couldn't find on their site again, frankly, isn't enough.

Do I need to explain how long the "obsolete and slow technology" thermal spring fan clutch takes to "turn on" and actually lock the dammed fan in while the ECT is running away on a grade? Start with a lower temp clutch and the runaway peak ECT is lower. There is still a thing, using the KD low temp clutch, with a summer and winter T-Stat temps that can also help lower the peak runaway ECT. All bets are off when you run out of cooling due to high ambient temps, small turbo, AC Load, and the fuel screw turned up. You don't need all the factors to roast the rings and crack the heads. Starting at a lower fan clutch temp simply gets the fan on sooner so it can stop the ECT rise. Yeah, you will hear more fan activity overall, but, the temp tolerance of IDI diesels are tighter than gas engines. Fuel economy from a hotter T-Stat is a debate where I can buy a lot of fuel for the roasted heads, rings, block, cam... (Hell, I even ruin engine oil.)

AC Performance is also helped by a lower temp fan clutch, but, really only after engine warm up.

I don't know that is needs to be said at this point, but, I will say it anyway. @Twisted Steel Performance I have some of his 'products' like a thermal dispersant coated new Mopar AC condenser I sent in. (And coated pistons in my 1993 "Patch" Project Thread.) Yeah, I took a gamble and dropped $400+ on replacing the condenser on my Dodge Diesel and got better AC performance results that I have posted up here and elsewhere. Yeah, same hesitation @Potluckslammy had at first. End of the day Chris @Twisted Steel Performance is the real deal.

So for additional cooling "coat the radiator" with a Thermal Dispersant.
 
Solid advice from WarWagon. I had looked at Kennedy's fan clutches. Considered the possibility of a TS coated rad, too. Hell...I'm looking at EVERYthing! Would love to get ALL the goodies! But this is a major outlay of cash...so having to weigh everything carefully, and decide what will meet my particular needs. At the same time, this is an investment....what goes in now will directly determine later performance and longevity. And I would much rather do it right the first time, rather than be forced to pull it back out and redo it later! I'm going to drive this beast for a LONG time!
So keep the advice and suggestions coming! Great input from everyone, it's all very helpful to me, and will likely be helpful to others down the road!
 
Just saying: Brakes, Cooling System and by extension GMx turbo that keeps heat in the engine forcing it into the cooling system are NOT the places to be cheap or frugal on. The cooling system can take the entire engine out and the cost difference of the KD fan clutch is less than $100.00.
 
I have used Kennedy clutches for years. I see AK Diesel Drivers set up as a better move for most people. I haven’t seen it in person, but how his description of it- heck yeah.

Controllability is huge. Being able to flip a switch when needed- shoot- that alone is magic.

Unless you want to beat me to my project- The adapter to a spin on waterpump is the hard part not made by anyone yet for a hmmwv fan clutch.

there is a hmmwv fan clutch on ebay for $45 after shipping

The other parts have already been done. More expensive than any of the other options, but will outperform any of the others in all categories. Then it never needs to be thrown away. The bearing & spring kits are $30, and the friction pads are $25- so a simple rebuild for $55. Occasionally the full kit of those parts together comes up for around $45.
 
Just saying: Brakes, Cooling System and by extension GMx turbo that keeps heat in the engine forcing it into the cooling system are NOT the places to be cheap or frugal on. The cooling system can take the entire engine out and the cost difference of the KD fan clutch is less than $100.00.

Excellent point, and well put. There are places not to be frugal. There's a point I haven't seen mentioned, the brakes. Has this been covered before, or have I just not discovered it yet?
 
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That's why I went with my electroviscous fan clutch. No delay in fan clutch kicking in as it uses engine temp to activate it vs waiting for the thermal fan clutch to engage

Now there's an item I'd like to explore more thoroughly, but can't seem to find anything. You have a part number?
Ah, I see from Will's post it's not a simple bolt on. Am I understanding that right?
 
Yeah, my thing is a major project. Something to play with after all the important stuff is done if $ left over.

I probably shouldn’t have thrown it out there really.
 
....all the part numbers are near the end and the clutch and fan are a direct bolt on for those with a spin on water pump

Ok, just finished reading from beginning to end. Excellent thread! Need you guys who have run it long term to give me you opinion...comparing durability/longevity to a severe duty clutch like the Hayden 2886...then I'll be convinced it's a much better option. Wish I had learned more before ordering what I did. But need to go back and read it again to understand how to run the electrics. Btw...that thread was from a few years ago...what happened go Leroy's kit?
 
Durability is going to be about the same as a thermal clutch, as well as lockup % etc. I know on my 99 the engine can easily hit 210 before the fan clutch engages especially when it's cool outside as the bimetal spring would take to long to heat up and engage the clutch. By switching based on coolant temps that delay is gone. Plus the added benefit of the over ride switch allows you to anticipate a big hill coming up and get it engaged before you hit the hill.
 
Leroy’s kit not came to be, at least as of yet. As with any r&d projects, I am sure he faced some hurdles. He won’t release one for sale until he is sure all the issues are solved. It really is not a small task, even though it may sound simple. It is also one of many things people have requested him to come up with.

There is a bunch of hummer and hmmwv owners out there hoping for big boy turbos as the best thing currently available is the gm7 with a wicked wheel. There is hope on that front, as someone sent me a pic of a larger turbo in a hmmwv the other day. He is talking about a kit for under 3k. But there is some weak points in his set up I saw. I Haven’t seen anything Leroy may have in that arena, but who knows...
 
I was seriously entertaining the idea of picking up a surplus Humvee...for about a week. Last I heard they weren't available surplus...but like I've said, been out of it for awhile. Now, come to find out they've been on the market for five years or so! But everyone has caught on, and prices are going way up! Oh well...missed out on buying a duece-and-half, too. But I digress... :D
 
For any military rigs- you have to make sure your state accepts them. Some states won’t register them even if they were previously registered in another state.

There are some hmmwvs still going for well under 10k. Several companies buying, fixing up then selling them for descent profit.

Thats what I wanted to do originally, buy one mechanically beat up, then go through it completely how I wanted it. The hmmwvs weren’t available at the time, so looked at hummers. then the one I have now came up for sale- that was over 15 years ago. They sure hold their value.

If willing to sell to the overseas market and invest in some bling, they sell for ridiculous prices.

There are companies doing hmmwvs up with motor swaps and lots of bling, then selling for close to 6 figures in the US. Then Overseas for ~150-175k
 
I was seriously entertaining the idea of picking up a surplus Humvee...for about a week. Last I heard they weren't available surplus...but like I've said, been out of it for awhile. Now, come to find out they've been on the market for five years or so! But everyone has caught on, and prices are going way up! Oh well...missed out on buying a duece-and-half, too. But I digress... :D


I have always told my wife ever since we were dating that one day she will wake up to a deuce and a half and a HMMVW sitting in our yard. She thinks im crazy for wanting the deuce but I think it would be cool as crap to ride around town in a flat black bobbed deuce and a half.
 
Yea, I wanted a doose real bad...still do! But prices now are higher than I want to pay. I'm pretty sure I could get a Humvee titled here...but the real low-mile, complete and running rigs go for upwards of 10 G's...some for LOTS more! Then there's the shipping, the UNKNOWNS that are bound to happen, the must have upgrades...yadda, yadda, yadda! Probably be $20K-$30K invested before I could even hit the road. Guess I'll just stick this new motor in my pick'em up truck, spring for some much needed paint, and count myself lucky.
 
Ok...so what I've got on the drawing board now is: New optimizer, clearanced and balanced, POSSIBLY cryo treated, with TSP low comp pistons. Have him port match the heads as well as coat the runners, combustion chambers, valve faces. Leroy's timing gears, his crank pulley, and a Fluidampr. New 3-row aluminum rad, new water pump, new 190 degree thermostats, new belt and tensioner. It think that just about covers it. Any comments on what I have so far?

Now I have a couple or three things I'm still considering. First, and least of all, would advantage to running one 180, and one 190 stat in the dual setup?

Next, undecided what fan clutch to run: 1) Keep the Hayden 2886 I have, possibly tinkering with the spring. 2) Going the electric setup. 3) Going hydraulic. On that last, I sent a message to Unique Diesel for an update on availability of a spin-on set-up.

Lastly, maybe I should replace the rebuilt IP I bought? What/who is possible for the DS4? Not a lot what i gather . And I really don't want to retro a DB2...but not beyond convincing, if someone can argue a good case.
 
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