6.2 to 6.5 Engine swap?

[gordonian]

I have an opportunity to get a 1986 M1031 CUCV with a badly ruined 6.2L engine.

I also found several opportunities to get a new, a surplus, or a rebuilt post-1995 6.5L with turbo, (& "improved" non-Chinese head/block castings) that some vendors are promising will "Drop right in" to a CUCV. (I suspect the truck will need a thicker radiator & new exhaust, & I'm fine with that)



I want a second opinion, from experienced folks who aren't trying to sell me stuff: Can a mid-90's or newer 6.5 Normally Aspirated Diesel, or a mid-90's or newer 6.5 TURBO-Diesel "drop right in" to a mid 80's CUCV that had a Normally Aspirated 6.2? and if that's not exactly true, what are the details?



If this is possible, it'll be helpful to develop a newbie's list of what to expect if I decide to take on this engine upgrade project. (not just for myself, but for other readers thinking of a similar upgrade, considering all the surplus or "Improved" 6.5's hitting the market these days)

As for me, I guess you could say I have "hobbyist" mechanic skills, I've done 2 or 3 engine rebuilds & replacements of Gasoline engines back in high school & college, and I've had some fun working on a '77 Mercedes non-turbo diesel 300D I had for a while, but this will be my first Diesel 4x4 project, (& my first turbo).


(TYPO: WHOOPS! I forgot to mention one of these vendors says these "Improved" 6.5's i refer to here, use REDESIGNED Engine Block and Head castings made After 2004 not 1995 --DOES THIS REDESIGN CHANGE THE ENGINE MOUNTS, OR FITMENT IN ANY WAY? )

 

[Recovry4x4]

Beware of center mount turbo engines. These require extensive firewall mods including moving the factory heater assy. Regular side mount turbo will work and N/A is easy. Do a little searching around, bunch of threads dealing with turbos and such.

 

[Westech]

You won't have to change radiators. The stock one will cool 450 hp.

 

[gordonian]

Beware of center mount turbo engines. These require extensive firewall mods including moving the factory heater assy. Regular side mount turbo will work and N/A is easy. Do a little searching around, bunch of threads dealing with turbos and such.

Thanks for the tip! I'm seeing a few of those center turbos around!

On the engine blocks, I I suspect the bell housing bolt pattern will match the TH400 (Is that correct?), but what about the engine mounts at the frame? are they the same too?

 

[cucvrus]

How about 451HP? Darn. Seriously what does HP have to do with cooling? No really. Never heard that before. Just asking for educational purposes.

 

[doghead]

There is a direct relation between HP, and BTUs.

http://www.arrowheadradiator.com/14...apability_in_high-performance_automobiles.htm

 

[Recovry4x4]

Bellhousing and engine mount bosses are the same.

 

[gordonian]

Bellhousing and engine mount bosses are the same.

for the post-2004 redesigned blocks, right? (sorry, just making certain)

 

[Recovry4x4]

http://www.steelsoldiers.com/showthread.php?66745-Dually-M1028A2-South-Florida-Rebuild&highlight=

That is correct. Stonepicker1 installed a GEP in the truck above and a new Optimiser in the CUCV II. Should bolt right in.

 

[cucvrus]

There is a direct relation between HP, and BTUs.

http://www.arrowheadradiator.com/14...apability_in_high-performance_automobiles.htm

I will have to read that some time when I have the time. I never looked that deep into things. Thank you for the post but it is to scientific for me to understand. I am just a parts replacer. Nothing personal I know you meant well. But I would get in to many arguments if I learned and looked into things that deep. It always happens on here when I think I know something. Thank you. And I really mean that.

 

[doghead]

Here a direct copy of a portion of that link I posted that might help explain it fairly simple.

It’s helpful to understand that, during operation, internal combustion engines convert the energy of fuel into mechanical work and heat. Approximately one-third of the fuel energy goes into the mechanical work of the moving vehicle, one-third into exhaust heat, and one-third into heat transferred by the engine cooling system to the ambient air.

This means that heat load to the cooling system at rated power (Usually expressed in BTUs per minute) is approximately equal to the rated power of the engine expressed in BTUs per minute (HP X 42.4 = BTU/minute). From this we can see that if an engine is modified to increase its horsepower, the load to the cooling system will also increase. In fact, the heat load to the cooling system will increase by about the same percentage as the increase in engine horsepower. So, if we increase the engine horsepower by 20 percent, we can expect an increase of about 20 percent in the heat load to the cooling system.

 

[cucvrus]

Aluminum vs. Copper/Brass Radiators Ok what is better? I want to truly know. It does not explain it in the link that I seen.

 

[doghead]

Better at what?

Corrosion resistance, budget, heat transfer?

There will not be a clear answer, depending on what you compare.

For stock cucvs, a stock copper core radiator is more than sufficient and readily available and affordable.

 

[llong66]

I have done just what the title of your post says, put a 96 6.5l turbo motor in my truck. I am currently running N/A as I basically ran out of time and money to finish with the turbo, mainly the exhaust. Other than relocating the rear battery to clear the turbo, and working out your crossover pipe, its a direct drop in. Most ppl that have done the swap run their exhaust out through the inner fender well and along the outside of the frame. I did not want to do this as I want to add a second fuel tank in the same way the factory did on trucks that were originally that way. I finally found some pics showing that it CAN be done, but around here anyway, its "custom" work and its gona cost, so I have put installing the turbo on hold until the spring. I had already installed an electric fuel pump as I was planning on this swap, just not NEEDING it when I did. One thing I did read that has been an issue for some ppl is the upper manifold clearing the VRV. This is going to depend on the position your VRV needs to be in for your tranny to shift properly. I THINK mine is going to be ok. If not, I have a friend who will make up a spacer for me from some 1/4 Al to go between the upper and lower intake. I really don't want to have to do that as I would think increasing the volume of the plenum will decrease the efficiency of the turbo. I am not real sure of that though as this is my first diesel and my first turbo.
If you have any other questions, please feel free to ask, I have already worked out my battery relocation, have the new cables I will need and started building the new tray, I am going to put both of then up front, pass side, they will just fit side by side. If you go with a banks setup, the battery and exhaust issues will be different, there are alot of posts and pics here with ppl who have gone that way.
Good luck!
Greg

 

[gordonian]

I have done just what the title of your post says, put a 96 6.5l turbo motor in my truck. I am currently running N/A as I basically ran out of time and money to finish with the turbo, mainly the exhaust. Other than relocating the rear battery to clear the turbo, and working out your crossover pipe, its a direct drop in. Most ppl that have done the swap run their exhaust out through the inner fender well and along the outside of the frame. I did not want to do this as I want to add a second fuel tank in the same way the factory did on trucks that were originally that way. I finally found some pics showing that it CAN be done, but around here anyway, its "custom" work and its gona cost, so I have put installing the turbo on hold until the spring. I had already installed an electric fuel pump as I was planning on this swap, just not NEEDING it when I did. One thing I did read that has been an issue for some ppl is the upper manifold clearing the VRV. This is going to depend on the position your VRV needs to be in for your tranny to shift properly. I THINK mine is going to be ok. If not, I have a friend who will make up a spacer for me from some 1/4 Al to go between the upper and lower intake. I really don't want to have to do that as I would think increasing the volume of the plenum will decrease the efficiency of the turbo. I am not real sure of that though as this is my first diesel and my first turbo.
If you have any other questions, please feel free to ask, I have already worked out my battery relocation, have the new cables I will need and started building the new tray, I am going to put both of then up front, pass side, they will just fit side by side. If you go with a banks setup, the battery and exhaust issues will be different, there are alot of posts and pics here with ppl who have gone that way.
Good luck!
Greg

Thanks!

Dual tanks was something I wanted to try too! I will need to be prepared to drive my rig about 100-150 miles, and then use the M1031's generator for most of the day or night at my destination & come back home. When you get back to the dual tank job, could you post a bunch of photos showing us how you did your conversion?

I've been considering a vendor out there who is offering a new style reman 6.5 with a side-mounted borg-warner turbo already installed, everything ready to drop right in, Wasn't Borg-Warner the stock turbocharger for the 6.5?

I've seen photos where some folks put both batteries side by side where the front battery goes. It looked like both batteries fit on the existing tray?? or was that just a custom tray & hold-down frame they bought someplace?


( . . . and please pardon my ignorance, -I'm still kindof new to Detroit Diesels, but what did you mean by "VRV"-?? )


Also, I heard only the Pre-1995 6.5's equipped with mechanical fuel injection/post 1995's are electronic, But you installed a 1996 6.5 in your CUCV, (I'm assuming your CUCV is a 1980's model that had a 6.2) so how did you retrofit that fuel injection?


. . . I know thats a lot of questions. I've got a lot more, like: How to order the right configuration 6.5 TD to go into the older truck. (most vendors I see require a list of configuration specs when ordering your 6.5 TD. Some even discourage retrofit conversions like this), ranging to how to retrofit the 6.5 TD to a chassis, wiring harness, and fuel delivery system designed for a 6.2 NA properly, once the 6.5 gets delivered . . .


I guess I'm looking for a thread in here that would give a detailed description (or a "How-To") for swapping a modernized (GEP? Navistar-GM?) 6.5 Turbo diesel into a truck that originally had a 1980's model 6.2 , does such a "how-to" thread already exist?

 

[Recovry4x4]

VRV is the vacuum regulator on the injection pump. It controls the shift points of the trans. Physically, the GEP blocks are the same as the 6.2 blocks (outer dimensions). As far as electronic injection, 1994 was the first year for the DS4 pump.

 

[gordonian]

VRV is the vacuum regulator on the injection pump. It controls the shift points of the trans.

Thanks, I was wondering where the TH400 got its vacuum signal from on a Diesel.

Physically, the GEP blocks are the same as the 6.2 blocks (outer dimensions). As far as electronic injection, 1994 was the first year for the DS4 pump.

So Recovry4x4, looks like the 1980's CUCV's didnt have electronic injection on their 6.2's, but the 6.5 GEP's with the reinforced block & heads did. How did you and llong66 resolve that when you put the 6.5 GEP engines in yours?

 

[Warthog]

The electronics are only needed for the electronic injector pump. Swap it out for a mechanical and you are ready to go. All you need is the hotwire for the fuel shutoff.

The TH400 does require a vacuum source. That is where the vacuum pump comes into play.

Depending on how new the engine is, you may run into an issue with the oil pan. The newer engines require that you modify the oil pan. No one makes a replacement

And to answer your How-To question, No there is not a step-by-step on how to install the new engine. If it is just a long block, you pull the old engine, swap all the external parts to the the new one and reinstall. Adding the turbo requires some custom work and many people have done it. A few members have posted the highlights of their swap but not a "How-To"

Here is part of LLONG66's swap
http://www.steelsoldiers.com/showthread.php?130414-It-lives!!!-New-motor!!

 

[gordonian]

The electronics are only needed for the electronic injector pump. Swap it out for a mechanical and you are ready to go. All you need is the hotwire for the fuel shutoff.

When I saw they transitioned from mechanical to electronic, I kindof expected retrofitting the newer GEP to an older mechanical pump was necessary, (unless there was some aftermarket electronic solution, like they did with the 4l80 transmissions) but how involved is that retrofit job?? Are we talking new mounting plate, new camshaft? etc, or does the mechanical pump simply bolt onto the electronic pump's bracket & lines, prime it, time it, & move on?

My only Diesel experience to this point was maintaining the (NA) Mercedes OM617 in my uncle's old 300D I used to drive around in years ago. They had mechanical pumps too, driven off the flywheel if I remember right, pretty easy to reach & play with, but mine had priming issues.

The TH400 does require a vacuum source. That is where the vacuum pump comes into play.

Depending on how new the engine is, you may run into an issue with the oil pan. The newer engines require that you modify the oil pan. No one makes a replacement

Unfortunately, just about any engine upgrade is never REALLY a "drop in" replacement & will require a modification somewhere Anybody on here got photos of the mods we got to do to the post-2004 casting GEP 6.5's?


(I only say post-'04 since that year seems to have the most structural reinforcement, & looks like its showing up more in the crate motor & reman market now anyway)

 

[llong66]

You will need to used the lines from your mechanical pump, the end of the line that attaches to the pump is different on the DB4 pumps. All you really need to do is pull the pump and lines off of your current motor and swap it over, the steel part of the return line, just after the pump, where the inj. connect to is different also, I used my original part here. You want to be careful when you pull your lines as they have a coating on the inside and being ~30 yrs old it can come loose if the lines are bent, clogging your inj.
I was thinking of buying one of the "drop ins" I would do lots of research on the companies out there selling these at what look like bargain prices. I wont name any specific companies, but some seem to be VERY problematic from reviews. I do know that if you want to spend the money, Kennedy and Peninsular
are both excellent places but they are also pricey! In the end, I chose to rebuild my own, it cost a little more than the "drop ins" you see but less than the two places I did mention and I know it was done right with quality parts. The crank is one thing you want to watch out for, almost all the "drop ins" have machined cranks. GM says that because of the nitride coating on these cranks that they should not be machined. I've also heard of mis-matched or wrong size bearings and such. One re builder will offer a warranty, and I believe will even offer help with the labor on a warranty claim, but do you want to have to go through that?
On your "how to" if you go with one of the remans, you want to specify that you want the mechanical inj. and I personally would stick with the V belts, the V belt and serpentine setups use different water pumps. That is just a personal choice thing, I don't like the serpentine belt, its kinda like putting all your eggs in one basket. I know it can be done, but I am not sure what all is required to go serpentine w the dual alts. As far as fuel dilvery, I went with an elect. pump, just a factory replacement for a 93 I think truck. There is a skid plate on the pass. side where there are some rubber lines above, I located my pump there, put an inline filter in before it, wire and fuse the pump in an ignition on hot spot in the fuse box and there ya go! Makes priming a breeze too! On my M1008, right under the fire wall, there is a brass "T" where the fuel line from the tank stops, then another piece of steel line is run to the mechanical pump. since I went electric, I just replaced that line from the "T", straight up the fire wall to the filter. If you go factory turbo setup, the oil return for the turbo goes where your mechanical pump currently is.
As far as the batteries go, I am using the front mount as the base for my new one, just cut a piece of plate the correct size, tack it on and there you go. You could fit two batteries on the front base as it sits, but the tabs and up turned edges of the base would be supporting the weight of the batteries, I did not like that idea. I will build a new top piece, along the same lines as the original, maybe even using it, just cutting it and tack in the needed pieces to make it long enough for two.
I will for sure let you know how the fuel tank project goes, that is a ways down the road though. I plan on using all factory components, I already have the valve and switch, I will just get a new tank and straps and I believe it will bolt right in. The guy who is doing my cab corners said if I could find a truck in a salvage yard that has the area around the filler door in good shape, I could cut it out and he would be able to cut a hole in my current bedside and weld it in place. I'm not sure how hard its going to be to find a diesel to get the area from, the filler necks are diesel specific.
I am also going to be rebuilding my injectors and will be posting on that, w pics. That will be sometime after new years.
I hope this helps some, again, please feel free to ask if there is anything I or the other posters have not answered.
Good luck!
Greg