Cummins ISC 350 swapped out for ISL 400

[Tom Cherry]

3 hours ago, 96 EVO said:

Nope, it bolts right up to the stock head, right below the valve cover (which needs to be replaced with a slightly taller model). After install, you need someone with the Insite software to change setting in your ECM.

The Camelot / Scepter even has the wiring harness for the engine brake switch already in place.

A member on IRV2 recently made the mod on his ISC equipped Fleetwood RV. 

YES and NO.  In the case here, a PRE EGR or 2006 on back can NOT be retrofitted with a “bolt on” Jacobs Brake.

https://www.jacobsvehiclesystems.com/sites/default/files/2021-12/490A_Spec_Sheet_047250RevA_Cummins_ISL_ISL9_L9_ISC07_Engines_1282021.pdf

https://www.jacobsvehiclesystems.com/sites/default/files/2021-12/490A_Installation_Manual_26302_RevE_Dec_2021.pdf

Maybe I misread it, but there were several posts on IRV2 about this.  The 490A brake is actually a 3 speed, not low and high, like Monaco put on the 2007 + Dynasty and up 400/425 ISL.  

So, want a 2006 or older ISL….WITH a 2 speed Jacobs “head” compression (actually a misnomer) brake…..find one with a factory installed one.  

Now, Frank might chime in here, but I read the install procedure.  Not exactly a redneck DIY.  Aside from the fine tuning and the clearance or lash adjustments, there is also a warning….

Cummins Turbo requires a DIFFERENT Actuator.  One specially, I believe, for the increased back pressure.  That also involves a complete “reinstall” as well as calibration of the turbo.  I don’t think you have to pull the turbo, but the INSITE  software must be used to run the protocols for shutdown and restart.  May be wrong.

Then, the SECOND a warning.  The 490A must be a “Stand Alone” braking system and NOT be used in conjunction with an Exhaust Brake.  Jacobs does punt and refer you to Cummins for the ECM and wiring mods.  They also state in the write up that it is “compatible” with the Cummins engines, listed in the main table.  So…again, Frank’s area, I assume that the VGT Exhaust function  is removed or “modified” within the ECM to not interfere with the 3 level Jacobs 490A brake.

In our case….we could retrofit the 490A to our ISL.  The actuator used to be in the $400 - $500 range.  Can’t find a price on the brake, but there were listing for the “full set” on EBay for $900 or just the “guts” for $500…. No idea on he total parts, but new with valve cover and misc, probably $2,000. If 12 hours of shop….another $2,000.  

If you pursue this, keep us posted or start a new thread.  That is how we learn

BTW….there was some interesting threads on IRV2.  Seems like the Rear End also impacts, to a high degree, the effectiveness of the braking.  Our rear ends were the “economy” ones….4.30:1.   Dynasty was much lower….maybe 4.78 (memory.  I now wonder if the Scepter that I passed on with the Cummins 2 speed brake, would have as much (braking) power as a similar Dynasty….unless Monaco popped in the lower ratio axle.  Fascinating…..

[96 EVO]

1 hour ago, Tom Cherry said:

YES and NO.  In the case here, a PRE EGR or 2006 on back can NOT be retrofitted with a “bolt on” Jacobs Brake.

 

Neither myself, nor the IRV2 member who just did the mod, have pre EGR engines 😉!

Edited September 15, 2022 by 96 EVO

[96 EVO]

2 hours ago, Tom Cherry said:

 

Maybe I misread it, but there were several posts on IRV2 about this.  The 490A brake is actually a 3 speed, not low and high, like Monaco put on the 2007 + Dynasty and up 400/425 ISL.  

 

I believe they are calling the retarding the VGT is doing as the 3rd stage of braking.

Not 2 cylinders , 4 cylinders and 6 cylinders, like you would expect.

Edited September 15, 2022 by 96 EVO

[Ivan K]

2 hours ago, Tom Cherry said:

..  wonder if the Scepter that I passed on with the Cummins 2 speed brake, would have as much (braking) power as a similar Dynasty….unless Monaco popped in the lower ratio axle.  Fascinating…..

On this point, Jake is most efficient at high RPM, therefore the ECM is programmed to downshift to a chosen gear as long as the road speed safely allows it without over revving. It is a choice to make if driving certain descents again and again. Even with all that I have to stab the brakes on a steep long downgrade. In my case it is 4th gear but is easily changeable to accommodate any axle gear and preferred road speed. It has very little effect at low RPM and there is also a low MPH speed setting, all the way to zero, where the Jake disengages but I can manually downshift to keep the RPM high until almost at stop if I wanted to.

[96 EVO]

Ivan, I thought I'd maybe just park my coach with the engine brake parts in your driveway while your sleeping, and come back a few days later and it will be done ?

[96 EVO]

Sorry to Ken T for the slight hijack on your thread!

Physically they are the same engine. If the rest of your driveline can handle the extra torque, I think your main issue will be electrical!

[Frank McElroy]

4 hours ago, Tom Cherry said:

YES and NO.  In the case here, a PRE EGR or 2006 on back can NOT be retrofitted with a “bolt on” Jacobs Brake.

https://www.jacobsvehiclesystems.com/sites/default/files/2021-12/490A_Spec_Sheet_047250RevA_Cummins_ISL_ISL9_L9_ISC07_Engines_1282021.pdf

https://www.jacobsvehiclesystems.com/sites/default/files/2021-12/490A_Installation_Manual_26302_RevE_Dec_2021.pdf

Maybe I misread it, but there were several posts on IRV2 about this.  The 490A brake is actually a 3 speed, not low and high, like Monaco put on the 2007 + Dynasty and up 400/425 ISL.  

So, want a 2006 or older ISL….WITH a 2 speed Jacobs “head” compression (actually a misnomer) brake…..find one with a factory installed one.  

Now, Frank might chime in here, but I read the install procedure.  Not exactly a redneck DIY.  Aside from the fine tuning and the clearance or lash adjustments, there is also a warning….

Cummins Turbo requires a DIFFERENT Actuator.  One specially, I believe, for the increased back pressure.  That also involves a complete “reinstall” as well as calibration of the turbo.  I don’t think you have to pull the turbo, but the INSITE  software must be used to run the protocols for shutdown and restart.  May be wrong.

Then, the SECOND a warning.  The 490A must be a “Stand Alone” braking system and NOT be used in conjunction with an Exhaust Brake.  Jacobs does punt and refer you to Cummins for the ECM and wiring mods.  They also state in the write up that it is “compatible” with the Cummins engines, listed in the main table.  So…again, Frank’s area, I assume that the VGT Exhaust function  is removed or “modified” within the ECM to not interfere with the 3 level Jacobs 490A brake.

In our case….we could retrofit the 490A to our ISL.  The actuator used to be in the $400 - $500 range.  Can’t find a price on the brake, but there were listing for the “full set” on EBay for $900 or just the “guts” for $500…. No idea on he total parts, but new with valve cover and misc, probably $2,000. If 12 hours of shop….another $2,000.  

If you pursue this, keep us posted or start a new thread.  That is how we learn

BTW….there was some interesting threads on IRV2.  Seems like the Rear End also impacts, to a high degree, the effectiveness of the braking.  Our rear ends were the “economy” ones….4.30:1.   Dynasty was much lower….maybe 4.78 (memory.  I now wonder if the Scepter that I passed on with the Cummins 2 speed brake, would have as much (braking) power as a similar Dynasty….unless Monaco popped in the lower ratio axle.  Fascinating…..

I've seen a few discussion about a Jake Brake upgrade on IRV2.  If you're used to driving a heavy vehicle with a Jake Brake, the PAC or VGT brake just won't cut it on long grades.  Now, as for the Jake 490A upgrade, it is really a two stage Jake - it has two solenoids each controlling 3 cylinders.  They are stretching the third stage because they are using a feature of the electronic actuator on the VGT for enhancement of the Jake brake.  Cummins calls it two stages - the manufacturer of the 490A calls it 3 stages.  

Its interesting that even the Monaco Signature ISX engine has just a High / Low Jake brake switch but inside the ISX it is a 3 stage Jake Brake.  There are 3 solenoids, operating 1, 2, or 3 cylinders.  From memory, I believe on Paul Whittle's coach low is operating Jake on 4 cylinders and high uses all 6 cylinders.  At least that's how the High / Low switch is operating the Jake solenoids.  Paul, please correct me if I'm wrong.  Paul - are you planning an upgrade to put in a high medium low jake brake switch?

As for actually doing the Jake brake upgrade, I'd say if you have done overhead valve lash adjustments on a Cummins diesel, you likely know enough to do this modification.  Besides, if you ever need to do a future overhead adjustment, you first must take off the Jake valve assembly to adjust the valve lash and then reinstall the Jake and do the Jake clearance adjustments.

Making the edits to the ECM parameter settings is the easy part.  This is just a software edit using Cummins Insite.

[96 EVO]

Yeah, I think setting the exhaust valve lashes is the most technical part of the change. I have a HD mechanic that I could get to check my work.

I just need to find a complete kit at a reasonable price before I proceed!

[Ken Thompson]

3 hours ago, 96 EVO said:

Sorry to Ken T for the slight hijack on your thread!

Physically they are the same engine. If the rest of your driveline can handle the extra torque, I think your main issue will be electrical!

Hey, no worries. I enjoy new knowledge. Especially when it’s free. 

4 hours ago, Ivan K said:

On this point, Jake is most efficient at high RPM, therefore the ECM is programmed to downshift to a chosen gear as long as the road speed safely allows it without over revving. It is a choice to make if driving certain descents again and again. Even with all that I have to stab the brakes on a steep long downgrade. In my case it is 4th gear but is easily changeable to accommodate any axle gear and preferred road speed. It has very little effect at low RPM and there is also a low MPH speed setting, all the way to zero, where the Jake disengages but I can manually downshift to keep the RPM high until almost at stop if I wanted to.

 

1 minute ago, Ken Thompson said:

Hey, no worries. I enjoy new knowledge. Especially when it’s free. 

I’ve heard a lot of guys have it shift to 5th so it isn’t so abrupt. Then manually go to 4th if needed. I suppose it depends on gear ratio.

[TimSpencer]

Not having made this particular engine swap but having done several others in my life. If the engine can physically be attached to the trans and chassis the hard part is done. Now assuming you have everything needed to run the engine (ecu, fuel system, exhaust, etc) you just as Monaco did will need to sort the wiring. Original wiring print and new print. All the connectors should be available if a conversion harness is easier or you can depin your original connectors. Sorting through the wiring prints can be done well ahead of time. As far as can the trans take the extra power and torque only Allison or time can tell. I think we all would like to know how it works. Good luck 

[Ken Thompson]

2 hours ago, TimSpencer said:

Not having made this particular engine swap but having done several others in my life. If the engine can physically be attached to the trans and chassis the hard part is done. Now assuming you have everything needed to run the engine (ecu, fuel system, exhaust, etc) you just as Monaco did will need to sort the wiring. Original wiring print and new print. All the connectors should be available if a conversion harness is easier or you can depin your original connectors. Sorting through the wiring prints can be done well ahead of time. As far as can the trans take the extra power and torque only Allison or time can tell. I think we all would like to know how it works. Good luck 

I did find 2 different ECM's that were used on the years I am looking for, the CM 554 that I have, and the CM 850. After looking at the wiring diagram from both, the 554 would be a direct swap. I may have to do some wiring to change the pac brake to the 2 stage jake. People have said that Monaco over wires their coaches, so there may already be wiring ran to accommodate the jakes. By using the engine with the CM554, I am stuck with the CAPS fuel system. I have already added the Airdog fuel pump system on my ISC, so I should be fine in that aspect. I currently have a call into Allison about the torque converter. Once I figure that out, it's time to open the big checkbook! The shop I'm having do the work is concerned about the size of the radiator. My sister has a Monaco with the same ISL I'm looking at getting, so I will compare radiator part numbers.

[TimSpencer]

I would try to buy engine with its original ecm, rewire as needed. Radiator maybe something that is a wait and see. I would definitely send it out for cleaning and pressure testing and if shop feels there is an issue then  upgrade. 

Edited September 15, 2022 by TimSpencer

[Ken Thompson]

Since not many on here have needed to do an engine swap, I'm probably asking the wrong people. The only used engine I can find with the CM554 ECM is in Florida from JJ Rebuilders. After doing some checking, I have found their reviews are terrible at best. Only about 10% are satisfied. Most either didn't get the engine they purchased, parts were missing, or they didn't get their core charge back. Juan, the owner doesn't take the calls or answer e mails. I may have to bite the bullet, put on my big boy pants, and get Cummins to build me one. A 2 month wait just to get the engine! Their quote for the 2001 ISC was $24k without labor. I'm hoping the ISL will be close. I am concerned about the labor cost for swapping them though. Cummins of Portland has quoted me $12,455. At the $190 per hour rate, that's over 65 hours. When I went to the shop to see the damage to my engine, the mechanic told me he could have this one out in 10 hours, and the new one installed in 20 hours. I'm wondering where the other 35 hours are at. The service manager originally told me that the diagnostic was $400. Then they wanted another $750. Then they wanted another $1000. This is all for removing the valve cover and the pan. I paid the $400 and the $750, but when they asked for the $1000, I asked how many hours they had into it so far. He told me they didn't know. When I asked how they can ask for more when they don't know how many hours they have into it, there was a bit of a guilty look on their faces. I don't mind paying a fair price for the services provided, but honestly, I could have removed the valve cover and pan myself in less than 2 hours. I am currently searching for another shop to do the swap. Since the engine has to go out the bottom, that limits who can do it.

[JDCrow]

Not necessarily the wrong people, as the not experienced people.

I’ll be honest, just going over what you’ve said, I believe you will be the one with the most knowledge on this no matter where you go. 
 

To me, your best bet will be to find a shop/person who will sit down, take the time, and map out a solution. A person that will be excited/intrigued by the whole process. 
 

If you start piecing it all together, some work here, there, I think you’ll run into trouble. 

[Guest Ray Davis]

Have you checked the RV salvage yards?   I stopped at this place one time and I saw several engines in their warehouse ready to go.

https://colawrvsalvage.com/

This site allows you to search by state etc.  https://camperfaqs.com/rv-salvage-yards

[Ken Thompson]

Oh yeah, extensively! I checked state by state. 

[Dr4Film]

Personally, I would trust VisoneRV and ColawRV for their used engines even though you are buying as-is no warranty.

Both have multiple Cummins engines.

Edited September 16, 2022 by Dr4Film

[Ken Thompson]

10 minutes ago, Dr4Film said:

Personally, I would trust VisoneRV and ColawRV for their used engines even though you are buying as-is no warranty.

Both have multiple Cummins engines.

I totally agree. Colaw doesn't have anything that matches the CM554. I am waiting for a call back from Buckey at Visone RV this morning. Fingers crossed! Unfortunately, there is only a few years of the ISL that used the CM554 ECM.

[Guest Ray Davis]

What about the turbos, are they the same for ISC & ISL?

[Dr4Film]

The engines that I have viewed on VisoneRV usually have the turbos attached and go along with the engine.

Haven't spent any time on the ColawRV site.

Edited September 16, 2022 by Dr4Film

[Ken Thompson]

3 minutes ago, Dr4Film said:

The engines that I have viewed on VisoneRV usually have the turbos attached and go along with the engine.

Haven't spent any time on the ColawRV site.

Yes, the engines I am looking for have everything on them.

[gjh2916]

VisOneRV in southern KY has used cummins engines here is a link to a ISL 400 RV Chassis Parts USED CUMMINS ENGINES FOR SALE | CUMMINS DIESEL ENGINE | 2002 8.8L ISL 400 FOR SALE - 94,000 MILES Cummins Diesel Motors | USED CUMMINS ENGINES FOR SALE | CUMMINS DIESEL ENGINE | 2002 8.8L ISL 400 FOR SALE - 94,000 MILES (visonerv.com)

[Ken Thompson]

1 minute ago, gjh2916 said:

VisOneRV in southern KY has used cummins engines here is a link to a ISL 400 RV Chassis Parts USED CUMMINS ENGINES FOR SALE | CUMMINS DIESEL ENGINE | 2002 8.8L ISL 400 FOR SALE - 94,000 MILES Cummins Diesel Motors | USED CUMMINS ENGINES FOR SALE | CUMMINS DIESEL ENGINE | 2002 8.8L ISL 400 FOR SALE - 94,000 MILES (visonerv.com)

Thanks! I am currently waiting for Buckey with Visone to call me back on this one, and any others he might have.

[Ken Thompson]

Since the older ISL with the CM554 is near impossible to find, just wondering, why I can't take any year ISL 8.8 or 8.9 engine and use my bolt on components, like the exhaust, intake, ECM, etc.? Since the main block is the same. Am I just an idiot?

[TimSpencer]

1 hour ago, Ken Thompson said:

Since the older ISL with the CM554 is near impossible to find, just wondering, why I can't take any year ISL 8.8 or 8.9 engine and use my bolt on components, like the exhaust, intake, ECM, etc.? Since the main block is the same. Am I just an idiot?

That sounds possible and would be a heck of a lot simpler.