VT356 To Cummins ISL 400 repower

[SlimTim]

Hello, My name is Tim and I don't currently have or plan owning a skoolie however, I truly enjoy reading about what each of you are building. It's refreshing to see an online community that supports each other rather than complaining about this and that. It also nice to see people try different things without everybody jumping on the thread and talking about this will cause a lawsuit or some other legal recourse. By this time you may be asking why (other than to complement our community) is this guy posting, and what does any of this have to do with a VT365 to ISL400 engine swap.

I have a 2010 Gulf Stream 6400 Supernova RV. If you are not familiar with the GS Supernova it was Super C RV built from 2007 to approx. 2012 and utilized an International 4200 chassis. Most of the Supernovas utilized a VT365 engine married to an Allison 2500 transmission. However, at least one was built with a DT466 and Allison 3000 transmission, and I suspect there is one other one built with a 6.4 Maxforce or it could be a DT466 as well. I always loved my GS Supenova as it drives quite well but the 300hp VT365 was a little under powered when climbing hills out west. (Yes, the Supernova's came from the factory with a 300hp VT365 engine) So I always dreamed about doing an engine swap but everybody said it could not be done. Well I am the type of person that if you say it can't be done, I am going to try it. At this time I do not have everything put back together yet but I am getting close. I have attached some photos and have many more if anybody would like to see them.

So the reason I am posting on skoolie.net is that. 1) I felt if any group of people would appreciate the project it would be this group. 2) I believe the International 4200 shares some common features with the International school busses. 3) If anybody was thinking of repowering their VT365 bus I would be happy to help in any way that I can.

As mentioned above, I have lots of photos so please let me know if you would like to see anything particular.

Tim

[Jolly Roger bus 223]

cool.
nice shop.
and that by itself makes me jealous?
did you have any problems mating the same tranny to a different motor?
why did you choose that motor?
i know alot of questions but i am a gearhead and want to know things?

[SlimTim]

Originally Posted by Jolly Roger bus 223

cool.
nice shop.
and that by itself makes me jealous?
did you have any problems mating the same tranny to a different motor?
why did you choose that motor?
i know alot of questions but i am a gearhead and want to know things?

The Allison 2500 would have physically mated up to the Cummins ISL without any issues. However the 2500 is only rated to approx. 350HP and 700 or 750 torque. In addition the torque converter would need to be changed do to the slower RPM of the ISL vs. the higher RPM of the VT365. Because of this I installed an Allison 3000 when I installed the ISL400.

I looked at three different engines in preparation of doing the engine swap. 1) DT466/570, 2) Cummins 6.7 ISB, and finally the Cummins ISL 400 (8.9 Liter). The DT466/570 would have been the easiest, but finding a used DT with less than 250k miles and in a high HP/torque is nearly impossible. Because of this I crossed this one off of the list. The Cummins 6.7 would have been an easy swap as I could have retained the Allison 2500. If I did this again I would probably choose the ISB 6.7 engine over the ISL. However I wanted more HP so I crossed the 6.7 off the list leaving me with the the ISL 400; I could have also used the ISC (8.3 liters) as they have nearly identical engine blocks.

Low mileage Cummins ISB, ISC, and ISL engines are relatively easy to find in RV wrecking yards. They are also rated at higher HP seeing as they came out of an RV vs. a school bus or truck.

[Dbacks2k4]

Nice! 4 years ago I asked my mechanic about swapping out a junk vt365 for a dt466e or a Cummins on a 2005 IC RE200 party bus conversion. He told me anything was possible given enough time and money haha, but we wound up scrapping that bus (it had numerous other issues) and starting from scratch. That was a cheaply built party bus though, not a nice looking rv...

[SlimTim]

Originally Posted by Dbacks2k4

Nice! 4 years ago I asked my mechanic about swapping out a junk vt365 for a dt466e or a Cummins on a 2005 IC RE200 party bus conversion. He told me anything was possible given enough time and money haha, but we wound up scrapping that bus (it had numerous other issues) and starting from scratch. That was a cheaply built party bus though, not a nice looking rv...

If you had a donor vehicle the cost and time would not be to bad. If you had to go buy the engine and then every other little piece and part it would be expensive.

In my case I loved my RV and I did not want to spend the big $$$ to buy one that had the engine and transmission I wanted. I mostly dry camp and I figured out quite quickly that as soon as the wife could not take a shower the camping trip was over. The GS 6400 came from the factory with 150 gallons of fresh water storage, 110 gallons of gray water storage and 110 gallons of black water storage. Wife has never used all 150 gallons of water so no early departures since purchasing the GS.

[cadillackid]

what did you do for gauges / air conditioning etc that on the 4200 series truck run off of the BCM and specific data on the J1939.. (IHC proprietary PGN / SPN)..

[SlimTim]

Originally Posted by cadillackid

what did you do for gauges / air conditioning etc that on the 4200 series truck run off of the BCM and specific data on the J1939.. (IHC proprietary PGN / SPN)..

I am using all of the stock International gages.

I have not checked to see if the AC works yet but hopefully I will be able to by the end of this coming weekend. The VT365 AC compressor was not going to work on the ISL so I needed to use the AC compressor that came with my ISL. This required me to have two new AC hoses made up as the compressor was in a different location and had different connections. If you are located in or near Portland, OR and need your AC hose fixed, modified or a brand new one made I would recommend Premier Rubber & Supply. Premier cut my factory hose, extended the length and crimped on the correct end for the new compressor. The other issue I have/had with the AC compressors is that the VT365 compressor is a two wire clutch and the ISL AC compressor is a single wire clutch. After doing some online research and testing with my ohm meter it appears one of the two wires is just a ground. Knowing this I put a new two wire connector on the ISL AC compressor with the one factor wire still going to the clutch and I added a new second wire that is grounded to the body of the AC compressor. I will let you know if this works.

First let me say I do not know all of the correct terminology when talking about comm data so go easy on me. You are correct, the 4200 has a BCM with J1939. I am not sure about (IHC proprietary PGN / SPN) but as far as I can tell all big trucks using J1939 have standardized on the J1939 message data. For example, when the BCM sees a J1939 XXXX data packet it knows XXXX is oil-pressure. The BCM does not care if the XXXX came from a Cummins engine, International engine or a Detroit Diesel engine, it just knows XXXX is oil-pressure. So all I needed to do was connect the J1939 from the Cummins ISL into the Internationals J1939 BUS and all of the factory gages worked. The one gage that I have not confirmed yet is the speedometer. It is not 100% clear to me how the speedometer calculates the correct speed. I know the speed signal comes from the Allison transmission so I am assuming the transmission output RPM and rear diff gear ratio must all be worked out in the Transmission Control Module. If you have a good understanding of this, please let me know.

FYI - When I was doing my initial research to see if this would work I discovered all international trucks from approx. 2005 through mid 2007 used the some wire labelling, connectors and BCM; they even use the same cab. This led me to believe the BCM could talk to the ISL J1939 because although International never put a Cummins engine in the 4000 series trucks during this time. International did put a Cummins ISM in their larger trucks and the ISL and ISM share the same ECM programming. I am not sure if I can upload a video to this site, but if you want to send me a PM with your email I can send you a video of the dash when starting the engine.

[SlimTim]

I used PVC as a mock-up for the new exhaust. It relatively cheep, easy to work with and was a good way to see what would and would not work.

Because the ISL is longer and sets taller than the VT365 I had to make a new fan shroud. I initially thought about making the shroud out of sheet metal but I ended up making it out of fiberglass. this was very fun and I learned a lot on how to make flowing curved pieces out of fiberglass. I should have filled and sanded the outside a bit more before painting it, but I was tired of fiberglass dust being on everything.

[SlimTim]

The Allison 2500 is shifted mechanically using a push/pull cable vs, the 3000 transmission that is fully electronic. This meant I needed to install the Allison push button shifter someplace. One option would have been to use the stock International push button bracket/holder. However, my International has the Wabco electric over hydraulic brakes and a cable operated park brake and this makes the area between the seat and the dash a bit crowded. So instead of using the factory International shift pad bracket that attaches under the dash and would have made the area between the seat and dash even more crowded I fabricated a new shift pad holder. See photos below.

[Tejon7]

This is pretty cool stuff. Thanks for sharing the process!

[cadillackid]

cool stuff.. i wondered if the BCM used any proprieatary items.. the A/C I believe is operated via the BCM.. the clutch signal should be a ground and a positive wire.. they use 2 wires as they look for an open or shorted circuit / reversed connector as to protect the ECM.. you should be fine..


I ditched crimp A/C lines and go with reduced-barrier burgaflex for years now.. so much easier to deal with than the old school stuff... then again im often repairing , reconfiguring, or adding A/C with busses so the newer style lines are much easier to work with..

[SlimTim]

Originally Posted by cadillackid

cool stuff.. i wondered if the BCM used any proprieatary items.. the A/C I believe is operated via the BCM.. the clutch signal should be a ground and a positive wire.. they use 2 wires as they look for an open or shorted circuit / reversed connector as to protect the ECM.. you should be fine..


I ditched crimp A/C lines and go with reduced-barrier burgaflex for years now.. so much easier to deal with than the old school stuff... then again im often repairing , reconfiguring, or adding A/C with busses so the newer style lines are much easier to work with..

It sounds like you have a better grasp on the AC system than I do. I am going to try and recharge the AC this Friday so assuming all goes well I should know by the end of this weekend if it works.

I had to Google burgaflex fittings to see what they are. Can you use this style of fitting for both the high pressure and low pressure AC lines?

[Jolly Roger bus 223]

yes they can be used for both lines.
my issue was finding them.
i had to buy them online.

[TJones]

Awesome project! You will be lovin all that additional horse power a torque!

Ted

[LargeMargeInBaja]

Tim,
Are you going mechanical, no computers, with a tried-n-true Cummins 12-valve?
.
Our 1996 Cummins 505ci is a 'two-wire', requiring just two wires for the rig to operate.
.
I, and the editor looking over my shoulder, realize we are dinosaurs, content to putter along in the slow lane.
Based on our experience, the trade between rushing up a mountain highway is continually offset by the resilience inherent to our older rig.
.
As a bonus, most of the warranty issues are done...

[cadillackid]

Originally Posted by Jolly Roger bus 223

yes they can be used for both lines.
my issue was finding them.
i had to buy them online.

I have a hookup through ProAir, however Trans/AIR uses them now so you can get them direct from TransAir or don-brown bus sales..



the Goodyear Galaxy 4860 (or preferrably 4890) Hose is what these are made for.. although any reduced-diameter barrier hose will work..



iver never had a leak with goodyear 4890 Hose.. costs more but for me that "well crap the A/C isnt cold" is a non-starter for me so i use good parts


its 92 with a heat index of 103 so far today and im in a 45 year old bus.. its blowin so cold people are pointing at me at traffc lights thinking im leaking water

[Bearmtnmartin]

Nice project. I am almost done squeezing a Cummins ISM and a roadranger 13 speed into my Wanderlodge. I went from 210 hp 450 tq to 500 hp 1550 tq. I thought about the ISL but I wanted a proper engine brake. The ISL would sure have fit better though.

[SlimTim]

Originally Posted by Bearmtnmartin

Nice project. I am almost done squeezing a Cummins ISM and a roadranger 13 speed into my Wanderlodge. I went from 210 hp 450 tq to 500 hp 1550 tq. I thought about the ISL but I wanted a proper engine brake. The ISL would sure have fit better though.

I considered the ISM for my project but it was just to big to fit in the engine bay. International did put a ISM in this frame and cab but they raised the cab approx 6 inches and used a much deeper doghouse.

As a side note at least the common rail ISL did come with a proper engine brake. I know this to be fact because my ISL has a Jake Brake on it.

Everything is back together on my project but I have not been able to take it out for a test drive yet. I have the Wabco Hydraulic Braking Unit and it’s throwing a code that I can’t seem to fix. It seems like the brakes are locking up when it throws the code and this is strange because the code fault should not cause this to happen. If anyone has the Wabco Toolbox software and is located around Portland, OR I could use some help.

[Bhplumber]

Tim , I was following your build on the RV site but haven't heard much recently. How did it all turn out? I have a SN 6331 that's up for sale to upgrade to something with more hp and trq I hate to do it as I love my SN and the upgrade is going to cost probably 60-80k. I am pretty mechanical but I don't think I'd tackle the swap you did. I live in South Dakota so finding someone to do the swap for me here would be near impossible. It might be cheaper though. I'd really like to know how you like it once you get the bugs worked out. How much do you think youll end up having invested in it when it's all done?

[Flying I 365]

Indeed even I’m curious to how this engine swap works out. Got me thinking of doing something similar to my bus, but opted to keep the VT365 for the time being.