Dodge 440 to 5.9 Cummins Diesel conversion

[ClydesdaleKevin]

You're almost there!!!  Can't wait for the maiden voyage report!

Kev

[DonD]

 

[Wantawinnie]

I just about forgot, I need to start worrying about insurance and AAA coverage now. I guess that is a good problem to have. 

[ssapmoc]

Wonder if you can pressurize the tank with an air hose and if that would bleed the fuel line from the tank to the pump. Then crack open the fitting to the pump to release the air in the line. I cant wait to find out what mileage you are getting in your new rig.

[Wantawinnie]

Exactly what I was going to try doing. Set the regulator down to about 10 psi and have a helper pressurize the tank while I wait for the air to purge and the hook it up. Last step is pumping the primer lever on the pump and crack the 10mm bleeder screw open on the fuel filter housing line.

Contemplating a electric pump back by the tank as well. My mechanic friend mentioned that if for no other reason but to help bleed the system if the need arises.

[ssapmoc]

Would you need to clamp off the return line so pressure would build or just let it flow back to the tank. I think clamping it off would not hurt and assure the tank pressure is pressing fuel just through the feed line. I would be there as a helper just to check out the project but I'm down south a bit in Virginia. Good Luck.

[Wantawinnie]

I don't think that is necessary. As long as the air doesn't get to the injection pump it should be fine. The lift pump has a manual lever on it and there is a bleeder screw on the filter. Also, the return line should help send air back to the tank and out of the system. There was a lot of air coming out the return when we were bleeding it before cracking the injectors.

The injection pump has to build enough pressure to pop the injectors. Any air in the pump means no pop of the injectors and it won't run.

[ssapmoc]

That sounds like you have it licked. I like the manual cable you wired for a shut off. COOL STUFF. Can't wait to hear when you have it on the road. I hope to do this on my 82 Itasca but I'm not sure what my mileage would be if I did the conversion. I have a 454 with a turbo 400 and a 4:26 rear. I checked out the Vendor Gear for the Cummins 5.9 and 4 speed automatic and almost feel out of my chair from the sticker shock. I'm trying to figure out how many miles I would have to drive to recoup the $3500.00.
 

[Wantawinnie]

I gave $750 for mine shipped from Ohio with a rebuilt 727 trans attached. That is the only reason I have one. I just changed the fluid out in it today in fact.

The standard overdrive automatic should do fine by itself. I am hoping for 14mpg and expecting 12-13mpg. The 500 mile road trip home with the 440 was in the 6mpg range. The aerodynamics and speed are the biggest factors. I'd guess you are somewhere around 8mpg with your rig.

[ssapmoc]

Man I wished I had your luck in finding one that affordable. What do you think about the school bus 6 speed Allison transmission. Would that give better gas mileage? I've read that they are very dependable and the Dodge Ram truck trans always needs to be rebuilt. My donor truck is a 4x4 and I would need to remove the transfer case somehow. I want to do this once and seeing what you have done it could be a pain to drop a trans and reinstall.

[Wantawinnie]

I've had no experience with the Allison's. Are they electronically shifted? The big thing with the Dodge trans is heat and lugging it in overdrive. I was limited in space above the transmission as the coach floor was right there. If the Allison is much taller or has a deeper transmission adapter that moves the bell housing back the floor and support structure would need modification.

Why not just leave the transfer case? I was going to do that for a creeper gear until the gear vendor came up. Nice for pulling out a boat at the ramp or maybe some maneuvering in campgrounds.

[ssapmoc]

I think the Allison in the early 94 and 95 school bus is non-electronic but are 6 speed. I'm not sure of the gear ratio but I believe they would have to be low to pull the weight. I didn't know I could use any of the transfer case for a creeper gear. I just thought it was dead weight without having it connected to anything besides the transmission. Would be cool to make a 4x4 RV but I think converting all the suspension would be more than I would take on. I only paid $200 for the RV so if I spend a little in it I will hopefully be able to get it back out if I ever sell it. I'm working with a budget and it needs rubber all around and that's something I want to buy new with warranty. Do you know how hard it is to disconnect the chasis from body. I was hoping to set mine on stands and roll out the chasis and do the conversion. I did that with a 1985 Toyota 4X4 pickup and put in a chevy 350 V8 with a turbo 350 trans sure made things a lot easier.

[Oz]

I swear, when you drive it successfully the first time, we're going have something like a Superbowl party!   

[ClydesdaleKevin]

Yep!  We need a big diesel conversion party...that does NOT happen during the months of August and September so we can be there too!!! :)rotflmao :)rotflmao :)rotflmao

Kev

[Wantawinnie]

There will be some celebrating when this is finally done! 

Today I topped off the engine oil with 2 more quarts of Mobil 15W-40 making a grand total of 14 quarts.

After that it was time for the transmission fluid, there were 8 quarts in the transmission from yesterday. I started it up and went through the gears. Added two more quarts and went through the gears. By now the old girl was moving back and forth.  Added 2 more quarts again and it was moving quicker. Put in 2 more quarts and it backed out of the shop under its own power.    After warming it up it looks like another 1/2 quart should do it making the grand total of about 14 1/2 quarts. I had two leaks at the transmission port fittings that needed resealing. Took care of that and then drove it around the lot a little to see how it acted.

There was a bunch of smoke in the rig from all the diesel fuel that leaked down the head, exhaust manifold, and block while priming the system. That finally burned off after about a 1/2 hour of run time. I let it run for quite awhile and brought it up to temperature and the thermostat opened up. Without the fans running it leveled off around 200 degrees after that. Kicked the fans in and it dropped down to a little above 160 degrees according to the temp gauge.(the temp guage is not the best layout IMO as the temp scale is a little weird) It was 60 degrees today so not really a good indicator of typical summer temps. Will have to see how that goes as the temps increase.

Oil pressure never dropped below 30 psi after warmup. The other good news is the power steering doesn't leak and the vacuum pump seems to actuate the hyrdo vac braking system fine. Unfortunately, the master cylinder leaked down on the rear brakes so that will need to be rebled.

Overall a good day. Still have some things to do before hitting the road for a test run but at least it is moving again.      

It's running in this picture after moving out of the shop.

[ssapmoc]

I call SHOTGUN.
HAPPY,HAPPY,HAPPY.
You did it !!!!!
Congrats

[LJ-TJ]

WOW!

[ClydesdaleKevin]

Awesome!  I hope your first trip is not only successful, but long enough to be give us some real time real life road data...lol!

LOVE it!

Kev

[Lefty]

Congratulations!!
I just have to say, that is such a pretty Winnebago. The body and paint are in such good condition.
You have done an amazing job on this conversion. I'm a mechanic, but I have very limited experience working with diesels. I could do the fabrication and the physical swap.. as far as making new mounts and brackets, and getting the engine sitting on them. But I don't have near enough knowledge to do everything needed to get it running. I've been reading your posts, and following along best I could even though a lot of it was over my head...lol But I thank you for teaching me a little bit about what would be required to do a swap like this.
It's still beyond my ability, but at least now I've got a better understanding about diesels.

[Wantawinnie]

I didn't know I could use any of the transfer case for a creeper gear. I just thought it was dead weight without having it connected to anything besides the transmission. Do you know how hard it is to disconnect the chasis from body. I was hoping to set mine on stands and roll out the chasis and do the conversion.

Meant to respond earlier but got busy.

On the transfer case, you would basically use it as is. Just leave out the front drive shaft.  For operation on the highway you would put it in 2wd high like normal. In situations where the low range is needed just stop and put it in 4 low as you would in the truck. The front flange will spin but it won't affect anything not being connected to a drive shaft. 4 High wouldn't be used for anything.

I can't help much in regard to removing the body. A lot of my fabricating was to accommodate fitting around body constraints in the engine compartment and transmission area. Those items would need to be in place to make it work.

[Wantawinnie]

Congratulations!!
I just have to say, that is such a pretty Winnebago. The body and paint are in such good condition.
You have done an amazing job on this conversion. I'm a mechanic, but I have very limited experience working with diesels. I could do the fabrication and the physical swap.. as far as making new mounts and brackets, and getting the engine sitting on them. But I don't have near enough knowledge to do everything needed to get it running. I've been reading your posts, and following along best I could even though a lot of it was over my head...lol But I thank you for teaching me a little bit about what would be required to do a swap like this.
It's still beyond my ability, but at least now I've got a better understanding about diesels.

Thanks Lefty!

It has been a challenging project. I had hoped the conversion process would take some of the questions out of a swap like this. As every chassis and body style have some differences there will be variations on what is needed. Hopefully,  the general theme and scope of what was done prove helpful if anyone decides to go with a diesel.

It was much more involved than a standard engine swap, maybe that is already apparent. 

[LJ-TJ]

I guess you've all ready gathered the gang has been pretty excited about this project and you've done a stellar job taking us step by step through the hole project.I can't thank you enough. Folks have been talking about a project like this for as long as I can remember.What you've done so far is show many of us the We possibly could take on a project like this and succeed. We can't wait to here how she runs and the kind of mileage you get with her and hopefully you will consider sharing what a project like this might cost one of us. Well done and good luck.

[M & J]

And take a video of her running and being driven and post it on YouTube.

[ssapmoc]

Thanks for that info Wannawinnie. I not sure if I would be able to make it work with the shifter location being the problem. I think the inside motor access box would be square in the way. I'm going to take a measurement from the rear of the block to the shifter location in the floor and see what I might be able to come up with. I look forward to reading about your test run. I really want to find out what kind of mileage you are getting and what rpm the vendor gear is keeping you at.

[vegas39]

I too am very anxious for a video! Keep an eye on the electric fan setup in hot weather and climbing hills, I gotta feeling what you have on there may not be enough. Keep us posted.