Community Forums

crah · 11-28-2011, 07:09 PM

What's the correct max boost for the stock ISC 350? Mine seems to max out at about 25psi on both my stock analog gauge as well as the banks analog gauge. I have a full banks system on mine and have no previous history to compare performance.

Mr_D · 11-28-2011, 07:33 PM

Stock is about 24-25 psi
On our ISC 350 with the Power Pack I see 34-35psi on the Banks gauge. My VMSpc I only show 24-25 even though the software is set for the Banks kit. Someone said I need to reset the max gauge reading in VMSpc but I haven't done it yet.

crah · 11-28-2011, 08:55 PM

Quote:

Originally Posted by Mr_D

Stock is about 24-25 psi
On our ISC 350 with the Power Pack I see 34-35psi on the Banks gauge. My VMSpc I only show 24-25 even though the software is set for the Banks kit. Someone said I need to reset the max gauge reading in VMSpc but I haven't done it yet.

Thanks for the info. I've never seen it beyond 25psi so I'm guessing I have some problems. I do know that my lights in the main box work, and my gauges are consistant, so I'm thinking my gauges work fine as well. Not sure where to even begin. I guess I could run the engine and check for leaks at the turbo area. Any suggestions on narrowing down the trouble shooting?

CJScepter · 11-28-2011, 09:58 PM

I would start by checking each clamp from the turbo to the intake. I had a boost leak on my previous 99 Monaco Banks equipted ISB, I went to Home Depot and got some pipe plugs that fit the hoses at the turbo output and at the intake to the engine, also went to auto store and got a steel air valve used in tubless tires. I drilled one plug and bolted the valve to it and put about 20 lbs. air to boost pipe. This ckecks from turbo thru cac to intake. You won't be able to hear anything with engine running and it won't make boost at an idle. I found a small leak at a clamp but only upped boost accuple of pounds. My trouble was the O-ring gasket from the turbo to the output housing, IT WAS NOT THERE! That was a 10-12 LB. loss. Also my exhaust temp would run high on all grades, had to always back off on the throttle, and would get some black smoke out the tailpipe when I floored it! If you are getting exhaust temps of more than 1250-1300 get it fixed ASAP, if staying below 1200 you probably won't burn a hole in a piston anyway. When fixed the boost went from 23 lbs. to 35 and EGT never to 1200 again!
Good Luck!
John G.

Lug_Nut · 11-28-2011, 10:10 PM

I had an '02 Newmar Dutch Star with a 350 ISC. I got a constant 23 PSI boost pressure for some 20k miles. I then changed my engine oil to Cummins recommended synthetic oil, Valvoline 100% syn. After running a thousand miles more or so, I got a contant 28 PSI. That remained for the duration of the coach.

Peter

mak1 · 12-20-2011, 11:28 AM

This may sound lame but I need some firm info on the set up proceedure for my coach. I just purchased a 2002 Monaco Diplomat 38pst 3 slide(what does PST stand for?). While reading the manual, I find bits and pieces of info like, make sure key is off when opening the kitchen slide, but no others are apparent. So my question is: How do you do it...in and out, in order. Air bags, slides and levelers....I have always had a 5th wheel and it was simple.

mak1 · 12-20-2011, 11:30 AM

Sorry, didn't mean to post this here

Mike Canter · 12-20-2011, 01:49 PM

Crah, the perfect EGT for a diesel under max load is 1300* F. That means everything is OK especially with a Banks kit. A diesel is reversed to a gasoline motor in that if you increase the fuel to a diesel engine then the EGT will increase. A gasoline motor is opposite and this confuses people. Banks tries to set them up that if you are climbing and making max boost then 1300* and maybe 1330* if a real long steep hill for a short time. In that case you let up a little or downshift it. If too low of an EGT then you get too little of an exhaust flame and you will not spin up the turbo so no big increase in boost. I worked on one with a Banks kit MH and could not make boost and the EGTs remained at 1200*. Finally installed new fuel filters and suddenly got more fuel so more more boost. Can you read the EGT on your motor and tell us what the max is under max load? Banks is very helpful in troubleshooting the system if you give them a call. All the manuals and installation guides are on line and can be downloaded.

crah · 04-11-2012, 10:25 AM

Quote:

Originally Posted by Mike Canter

Crah, the perfect EGT for a diesel under max load is 1300* F. That means everything is OK especially with a Banks kit. A diesel is reversed to a gasoline motor in that if you increase the fuel to a diesel engine then the EGT will increase. A gasoline motor is opposite and this confuses people. Banks tries to set them up that if you are climbing and making max boost then 1300* and maybe 1330* if a real long steep hill for a short time. In that case you let up a little or downshift it. If too low of an EGT then you get too little of an exhaust flame and you will not spin up the turbo so no big increase in boost. I worked on one with a Banks kit MH and could not make boost and the EGTs remained at 1200*. Finally installed new fuel filters and suddenly got more fuel so more more boost. Can you read the EGT on your motor and tell us what the max is under max load? Banks is very helpful in troubleshooting the system if you give them a call. All the manuals and installation guides are on line and can be downloaded.

Mike, it looks like I was a culprit of starting a thread and never getting back to it. I hate when that happens with OP's, but I've become one of them. I'm sorry I never got back to you on this. I must have not hit the send reminder email when someone else responds. As to your question, my temp gets to about 1300 on full throttle up long grades. The banks kit will shut it down if it exceeds that temp for any length of time. (my observation). I've checked all the connections as others have suggested, but never got to the point of hooking up an external pressure method (hate to have to do this if I don't have to). My annual oil/filter service is due this month so that will be done shortly. It could possibly be my air filter as I have not serviced that and don't know when it was done. I have another post over at rv.net on cleaning the AFE washable filter. My boost has never gone above 24-25 psi on both my analog boost gauges (stock and banks gauge). Perhaps air is the problem. My filter minder is too beat up to see what it says, but the actual gauge portion hasn't moved in over a year.