Problem with a 773G Cat haul truck

[kshansen]

We have had this truck for just over one year 1035 hours on meter!

Yesterday driver shut it down to fuel at the end of shift and when he tried to restart no crank.

Tried jumping with plug in jumpers and rear disconnect switch off same problem. Some lights woul;d work with key switch off but go out with it turned on.

Started checking the wires at the front bumper breakers with eky off had 25 volts, turn key on droped to 5.6 volts. Checking going back to starter and still very low volts. Decided to check out grounds, all looked good but when I checked grounding through the disconnect switch not good! Turns out the master disconnect swith was bad.

This one is the type with the disconnect switch and the jump start pug assembly all molded togeather. Parts book shows the disconnect switch to be separate part, same old 7N0718 but there is no way to disassemble ours. Sticker on assembly has the 237-7602 number but with a /05 after the part number.

I'll know better when the part comes in and I get to put it in on Monday, if the swich is replaceable on the new one.

We ahve some old machines that are over 30 years old that problably never had a switch replaced and this one just had it's 1,000 service and it's failed already hope this does not say anything about the rest of the wiring!

 

[Nige]

We have plenty of issues with the 7N-0718 (either installed separate or as part of the 237-7602 assembly) because of "Safety Rules" our operators must switch off the master every time they climb down for whatever reason. So a switch could go through an on/off cycle maybe 10 times or more a day.

237-7602/05 indicates that that particular Part # is on it's 6th level of development, known as the Engineering Change Level. Everything starts with /00, then /01, etc. Major modifications will result in a change of Part Number, minor changes the Part Number will stay the same and the EC Level will go up by 1.

If it was me despite the fact the truck's out of warranty I'd be complaining to my local dealer and asking for Cat to authorize a FOC replacement, or refund me the cost of the new part I'd bought.

 

[kshansen]

Well our "Safety Rules" are not quite that bad, as of now only have to turn off disconnect when parking machines. Did have to retro fit them to all machines short of pick-ups. Another "Safety Rule" is that wheels have to be chocked when ever you get out of machine. Even if on level ground with parking brake on and bucket on ground. Thing is they don't care how small the chocks are most machines have the small rubber chocks that you can back over at an idle with out knowing the were there. Another one new this spring is machines are to be parked no closer to another machine than 20 feet. Seems some plant had a fire start in a haul truck that went down the row of a few others. Seems like someone needs to be doing better maintenance on trucks so they don't spontaneously combust!

I just may ask our customer rep about getting credit for the switch.

We have plenty of issues with the 7N-0718 (either installed separate or as part of the 237-7602 assembly) because of "Safety Rules" our operators must switch off the master every time they climb down for whatever reason. So a switch could go through an on/off cycle maybe 10 times or more a day.

237-7602/05 indicates that that particular Part # is on it's 6th level of development, known as the Engineering Change Level. Everything starts with /00, then /01, etc. Major modifications will result in a change of Part Number, minor changes the Part Number will stay the same and the EC Level will go up by 1.

If it was me despite the fact the truck's out of warranty I'd be complaining to my local dealer and asking for Cat to authorize a FOC replacement, or refund me the cost of the new part I'd bought.

 

[ben46a]

There have been problems here on them with the battery cables being loose as shipped, and not checked on the pdi. Being that the batteries are under the box this causes a bigger problem than it sounds though.

 

[kshansen]

That was one of my first thoughts. Now that you mention finding some loose as shipped I'll have to make a point of checking ours.

Thanks, Ken

There have been problems here on them with the battery cables being loose as shipped, and not checked on the pdi. Being that the batteries are under the box this causes a bigger problem than it sounds though.