Mike SE IL

We have a firetruck that is causing us a problem. We're a small volunteer department. We bought new apparatus on a used chassis a few years ago because that is what we could afford. There is a company in Alabama that specializes in these. We bought a tanker from them several years ago and have been very pleased. This chassis was a rental (Ryder I believe).


The 4700 wasn't here very long before it developed a couple problems The simple one is it seemed to be losing power. The big problem was the engine quitting or the truck not starting. Took it to the IH dealer west of us (We're halfway between 2 of them) who replaced the high pressure pump, throttle position sensor, etc. The next time it failed they were covered over so we had it towed to the dealer east of us. They found a bad wire and had us up and going in 2 hours! This winter it started losing antifreeze into the oil. In frame overhaul and it's back going. I drove it home, backed up to the firehouse, and it died.


It started right back up but that made me a bit apprehensive. Yesterday we had a kitchen stove fire. Firefighter started the truck and went to put on his gear (SOP for us). Truck died. Cranked like there was no tomorrow, but would not fire ... kind of like pulling the coil wire on an old Chevy.



Typically when this happens the driver cranks it until the batteries are down, so we either jump it or put a 110 volt charger on it. After the batteries get back up it will usually fire right off. So to me it seems it is very sensitive to low voltage. Talking to IH service and one of our firefighters who is a mechanic they seem to think the varous computer components should not be that sensitive. If it has the juice to crank well it has the juice to work right.


One possibility throw out is a bad electrical connection or wire. Giving the voltage just a little boost is enough to overcome the resistance or bad connection and get things working.


I need ideas. Replacing it is not a possibility as this time. We are still a year or two from having it paid for. Even if someone gave us a new chassis it has been estimated it would take $5-$10,000 to get the apparatus switched over (This is one where the pump is driven by the main drive shaft. When pumping the truck will not move).


Anybody have experience with a 4700 with a 466E that can point me in the right direction?

Hvytrkmech

What year is the chassis, post up the vin.

One of the most common and overlooked problems on those is the ecm fuse caddy in the battery box. To verify, turn the ignition to the on postion without cranking it and see it the yellow engine light comes on for 3-5 seconds. If the light comes on then the ecm has power, try to start the engine and note how long it takes to start from initial crank, should be 2-3 seconds. When you encounter a stall or no start condition, cycle the key off then back on without start and look for the yellow engine light. If no engine light then check the 40a fuse caddy in the battery box, there should be 2 caddies with 40a fuses and 1 with a 10a fuse. Pay close attention to the fuse contact points, they loosen and cause condition as you describe. They also blow the fuses.

Check these things first then post back, we'll get you going in short order.

Mike SE IL

4 of us crawled all over and under this truck Thurs afternoon. I found s couple battery cables with corrosion on the wires inside the terminals. Both had the smaller wires coming off them
(my cell phone camera would not focus close enough to show the corrosion)
I removed the smaller wires, replaced the cable with a new 1/0 with better terminals than the one I removed, and cleaned and soldered the smaller wires to new 3/8 ring terminals which I then attached to battery studs, put a little dieletric grease in the weatherpack fittings and reconnected. We fired it up, it ran 2 seconds or less and died.

I guess a smilie is worth a 1000 words.

One thing that may or may not be a factor, both fuses are 15 amp ATC fuses. One of the guys called a diesel mechanic in Indy who said it sounds to him like a crankshaft sensor.

Here is how we feel right now:

Hvytrkmech

Do you have any way to scan it? If it has an "engine position" code then it could be a crank sensor. When they did the inframe or at some point was the front engine cover replaced? Also check for chaffed crank sensor wire where it crosses the front of the valve cover and turns toward the sensor. They chaff and short where it bends. Also check the HPO switch which is under the ECM. Look for oil saturated wire, if so pull the plug and see if oil is coming out of the connection. While your in that are check the injector plug pass through thru the valve cover. The locking prong break and the plug does not mate correctly causing those symptoms. An easy way to verify that is to hold it while someone starts the engine then wiggle it.

The ecm fuses are supposed to be 40a not 15. Does it have relays attached to the air intake cowl in the center of the firewall?

Have you checked fuel supply pressure yet?

Have you inspected the fuel debri/water screen behind the fuel filter?

Lets keep at, dont worry to much, one you fix the common issues those motors are super reliable.

Mike SE IL

I used to think that ...

Hvytrkmech

15a fuses with the older relays. You can use a generic fuel pressure gauge from autozone or rileys whatever store you have in that area. 45psi at idle 60-65 psi at 1000 rpm. The guage will bounce like crazy at idle, its normal. Shrader valve on the fuel filter manifold.

Dont assume on the front covern they usually dont remove it for an inframe, The reason I asked is because if the fron cover was replaced they need to pull the cam gear. If the cam gear is not properly seated back onto the cam it will forever cause engine position related drivability problems no matter how many sensors you throw at it.

Pull the fuel filter, behind it is a small plastic housing in the fuel line. Unscrew it, dump the fuel and check the screen. The screen is serviceable, spray it down with some brake clean and clean the plastic housing. You MUST fill that and a new fuel filter with fuel prior to installing.

Hvytrkmech

Any update?

Mike SE IL

We replaced the battery cables because there was some corrosion evident in the terminals, diconnected, cleaned and reconnected every plug we could find. One of our guys disconnected the cam shaft sensor, cleaned it, and reconnected it. So far every time since doing all this it has started and ran.