Kussmaul 1000 issues

[dfd37]

We have 2 2008 kenworth 4 door pierce 1250 pumpers in our fleet that have both recently developed issues with charging. The issue is that we plug these trucks in and overnight they over charge to 17.5 volts. Once started the lights surge (due to the alternator letting down is what I was told) and once they run a few minutes they operate normal. The problem is we have used these for over 2 years and havent had this problem until now. The trucks have 2 streamlight lite boxes each which are tied into the BS battery saver terminal. The trucks were both recently fully serviced and checked out at the Kenworth dealership and all was well with the trucks and chassis components. Puzzling. We have a kussmaul on 1 other engine and a F550 resue truck with no issues and they are older than these two trucks. I think though that their light boxes are tied straight to the truck batteries and not the kussmaul. Any help on this?

[FIREMECH1]

Anything you have that is high capacitance on the battery saver will pull the charger to the 17.5v. The streamlight chargers have a high capacitance, and should wired straight off the battery.

Rewire your streamlights to go off the battery directly, and it should take care of your problem.

FM1

EDIT: When we installed our MTD's, we hooked them up to the Battery Saver so they would stay fully charged and stay alive. Anything that has a rechargeable battery on it is considered to have a high capacity for voltage storing and charging. We had issues almost immediately. When we put the MTD's back on the battery, it cured all of our issues.

[FIREMECH1]

Note to self... Don't answer first time posters. sheesh.

FM1

PS: Hope the info helped, if you looked at it.

[rm1524]

I read it and learned from it boss. I have always hooked everything back to the batteries anyway. I was doing something right and didn't even know it.

[dfd37]

Note to self... Don't answer first time posters. sheesh.

FM1

PS: Hope the info helped, if you looked at it.

Sorry FM1, I have been looking at the problem. I took both lights off the chargers on both trucks and now the trucks still surge from about 12 volts to 15 volts for a few minutes when first started and then level out. This is still not normal, or at least has not been normal for these new trucks. I contacted the dealer about the lights being hooked to the Kusmaul and he immediately said that they would come down to our station and rewire it. He also appologized and said this repair was on them. The crazy thing is that the problem hasnt completely went away and I feel it should have. I will ask the Pierce guy when he repairs the light issue to look further. Maybe a ground has worked itself loose somewhere? I did notice that the ground wire from the chargers is tied into the same ground terminal on the kusmaul that comes back from the trucks batteries. Could this be affecting the voltage still? I havent actually unhooked anything as I want the Pierce guy to see exactly how it has been all this time and that we havent tampered with his wiring. Also I have another question. I have heard today that 4 door Kenworth cabs that Pierce build are no longer NFPA Compliant. Have you heard this? A friend of mine is specing out 2 new engines, 1 custom and 1 commercial and really wants to go with a Kenworth 4 door cab on the commercial. We have a call into our Pierce dealer and they are checking for us but has any body else heard this? This info came from another brands dealer (Sutphen) so it may just be a sales pitch. Anyway thanks for the info so far and looking forward to reading your reply.

[dfd37]

I also meant to say thanks FM1 for your help with this. Do you think a prolonged exposure to the higher voltage has somehow damaged or given these kusmauls some sort of memory? I mean maybe since they have been overcharging to 17.5 maybe they still do with or without the lights hooked to the battery saver terminal. Just a thought. Frustrating to go out and spend good money on a good product and have electrical issues this early in the game. Thanks again DFD37

[firepundit]

Sorry FM1, I have been looking at the problem. I took both lights off the chargers on both trucks and now the trucks still surge from about 12 volts to 15 volts for a few minutes when first started and then level out. This is still not normal, or at least has not been normal for these new trucks.

Actually, it is normal. In fact, a fully charged system should give you 12 to 12.5 volts without the engine running and about 14.5 volts with the engine running. If the engine is running and you only have 12 volts you have problems.

[FIREMECH1]

Some alternators will spike close to 15v on start up, trying to catch up with the initial electrical load put on the system. It should settle down (at idle) to 13.5v to 14v. So for now, I'd say that is normal.

Battery voltage at rest should be around 12.6 volts. 12v batteries have 6 cells. Each cell should produce 2.1v. Do the math, and you should have 12.6 volts.

It's good to see that the builder is taking care of the problem. As for the Kenworth/Pierce cabs, I don't know anything about them not being NFPA compliant. But I don't look for it either.

Glad to help, and welcome to the boards. Merry Christmas.

FM1

[rm1524]

Not NFPA compliant how? Last I heard that KW was working hard to stay up with NFPA and was ahead of all the other commerical cabs in being NFPA compaint.

Disclaimer - I was told that by a body builder that builds on whatever you want.