Old Bobcat 763 Rat chewed some wires

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Hi there My machine had rats chew threw two blue wires and two brown wires under the cab - they went through the outer protective case and into the mass of wires but only the 4 wires were fully eaten. They took approx 10cm of them - completely gone. I think the blue wires were to do with the glow plugs - when i tried to start, it went to 30 sec glow which it doesn't usually do - it usually only glows for about 9 seconds. I reconnected the blue wires and the glow period is back to normal. However i reconnected the brown wires but it was difficult to tell which one went to which one. before knowing the rat problem when I tried the key the ignition lights all came on (glow for 30 seconds but no crank) however, every now and then after a lot of tries it cranked, started and died like the fuel cut off had happened. STRANGE I rejoined the brown wires - they seem to be the thinner wires - like the thin one that goes onto the solenoid. It started to crank but fizzed out quickly to nothing - like a bad connections. I tried putting the shut off over manually and then the machine started and ran without a problem. Can I test this solenoid easily to make sure it works? - it has a red, black and white wire in the middle My other question is about the wire size and amps - I bought 15 amp wire but it looks more like the thick wire that runs through the mass of wires. Appreciate any advice. The electrical looks very complicated and I am very angry with those rats. The machine has been a cracker and shouldn't be brought down by such critters. Regards Shayne ps I will try and get a picture onto here if I can work it out.

 

[Tazza]

I never know wire gauges, but as long as it's the same size or larger, it will be ok.
As for the solenoid, get some wire with clips on it. Run the black to ground on the battery, the red and white will be pull and hold, not sure what one is which. Brush the +ve wire over the white and red pin, whatever one makes a big clunk is the pull coil. Hook the other one to the +ve and leave it there, this is the hold. Get another wire and brush it over the pull terminal, the plunger should snap back and hold in place till you turn the power off
Does taht make sense?

 

[[email protected]]

I never know wire gauges, but as long as it's the same size or larger, it will be ok.
As for the solenoid, get some wire with clips on it. Run the black to ground on the battery, the red and white will be pull and hold, not sure what one is which. Brush the +ve wire over the white and red pin, whatever one makes a big clunk is the pull coil. Hook the other one to the +ve and leave it there, this is the hold. Get another wire and brush it over the pull terminal, the plunger should snap back and hold in place till you turn the power off
Does taht make sense?

That does make sense Can't wait to try it tonight.

 

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That does make sense Can't wait to try it tonight.

Thank you for your help about testing the solenoid. When I touched it with power it snapped into action and seem fine. So I've reconnected the wires but the solenoid isn't clicking over when the key is on - so I'm guessing it's still a wire fault or maybe a fuse but I don't see any fuses in line with the solenoid - is there a particular place to look. It has fuses under in a box down behind where you legs go - they seemed fine. Is there other fuses closer to the solenoid? tracking back from the solenoid I can't find any. Thanks for any assistance - it is very much appreciated

 

[Tazza]

Thank you for your help about testing the solenoid. When I touched it with power it snapped into action and seem fine. So I've reconnected the wires but the solenoid isn't clicking over when the key is on - so I'm guessing it's still a wire fault or maybe a fuse but I don't see any fuses in line with the solenoid - is there a particular place to look. It has fuses under in a box down behind where you legs go - they seemed fine. Is there other fuses closer to the solenoid? tracking back from the solenoid I can't find any. Thanks for any assistance - it is very much appreciated

With the key on, it will not snap back, it should do so when you crank the engine.
Hopefully you can turn the key on, then push the plunger on the solenoid back and it should stick in place. The hold coil shold be on when the key is on, pull when cranking.
It could be a bad relay or connection too. When the rats ate the wires, they *may* have shorted and blew the fuse?

 

[[email protected]]

With the key on, it will not snap back, it should do so when you crank the engine.
Hopefully you can turn the key on, then push the plunger on the solenoid back and it should stick in place. The hold coil shold be on when the key is on, pull when cranking.
It could be a bad relay or connection too. When the rats ate the wires, they *may* have shorted and blew the fuse?

Hi Taza Yep the fuses in the main box all seem ok Are there others? I though I read posts where there were fuses in the engine area? My machine has the rectangular lights. Cheers Shayne

 

[Tazza]

Hi Taza Yep the fuses in the main box all seem ok Are there others? I though I read posts where there were fuses in the engine area? My machine has the rectangular lights. Cheers Shayne

I was pretty sure the fuses were all together.
Later model machines have it between your feet or behind the cab below the rear window. Older ones had them in the engine bay behind caps that make them look like a relay.
Or at least, on the machines i have worked on, this is where i have seen them.

 

[bobbie-g]

I was pretty sure the fuses were all together.
Later model machines have it between your feet or behind the cab below the rear window. Older ones had them in the engine bay behind caps that make them look like a relay.
Or at least, on the machines i have worked on, this is where i have seen them.

Shane, on my older 763C, there is no fuse block between my ankles. There are 8 fuses, all as Tazza described, in a small plastic box that looks like a relay. As you have the rear door open, look to the lower left of the inside of the door. Mine has a fuse block layout there, and the fuses are immediately adjacent to the door, just to the lower right of the engine. At least that's a place you can check. ---Bobbie-G

 

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Shane, on my older 763C, there is no fuse block between my ankles. There are 8 fuses, all as Tazza described, in a small plastic box that looks like a relay. As you have the rear door open, look to the lower left of the inside of the door. Mine has a fuse block layout there, and the fuses are immediately adjacent to the door, just to the lower right of the engine. At least that's a place you can check. ---Bobbie-G

Hi there I'm stuck with a new problem My tilt hydraulics stops working after 10 - 15 minutes The main boom stops after that - but the 4 way bucket hydraulics work I don't know where to start There doesn't seem to be any hose blow outs and when it does work it works properly. It seems to gradually stop working - and then the controllers go stiff Any suggestions will be awesome