New Guy :) 2007 Cat 315CL No Crank - need some guidance please

[Broke315CL]

Hello,

New guy here, trying to figure out an issue with our 2007 Cat 315CL excavator. We have been unable to start it for a while now and need some help as I have reached the extent of my knowledge on these machines, I have a background in automotive work but new to heavy equipment.

Basically its a no crank condition, as in turn the key to start and nothing happens (*** with one exception I’ll get to in a second). Here is what I know:

New batteries, fully charged and load tested, good 25V, does not drop when trying to start the motor.
New starter and solenoid I installed myself.
Main power and grounds seems fine, tight and clean and no resistance.
There is 24V to the starter itself.
There is 24v to the ignition key, I tested the key per the manual and it functions correctly in all positions, there is continuity between the contacts when appropriate and non when not appropriate.
Hydralulic lockout appears to function correctly.
Fuses in the box near the batteries all check out good.

***If you turn the key real quick from OFF past ON to START it will make one loud clunk as it bumps the starter but no cranking. If you turn the key slow from OFF to ON and then to START there is nothing at all.

My guess would be that there is something between the key and solenoid that is not working, either the starter relay or neutral safety switch, neither of which I can’t find info on in the manual. They are on the schematic but I don’t know where they are located physically or how to test them.

I think I need to see what is happening at the solenoid when the key is turned, both fast and slow and see if its getting the right signal, I did check the ground strap connection and thats all good.

I have heard of jumping the solenoid and starter and done if before on stuff like lawnmower but hesitant to do that on this 24v expensive machine that is not mine.

I have the old starter still, might take it to the store for testing, it worked the same as the new starter.

I would really, really appreciate any help, ideas of what to check from here. Like I said I am a bit out of my experience range but certainly capable of doing the troubleshooting with some guidance. I would really like to fix this as we spent a lot on the manual and don’t want to just throw parts at it. I have searched this forum, google, youtube etc….with little luck other than general stuff about batteries and starters being loose or worn out.

Thanks very much, nice community you seem to have here.

-Broke315CL

 

[Bls repair]

Check the grounds.

 

[Nige]

Post a Serial Number. You're welcome to an electrical schematic.

 

[Broke315CL]

Okay I'll check the grounds, I know I checked the main ones but I'll look for others I have missed. I remember testing the resistance between the ground strap and solenoid but not sure I actually measured to chassis ground. I know the battery grounds are good.

I can get the serial number but I already have the factory manual for the 315CL, it is huge and cost $700 and has a ton of schematics but they dont help if I can find the starter relay, the electrical components and location section is not helpful. There is little info on the starter relay or neutral safety switch, they are shown in the schematic and nothing else.

Thank you for the suggestions!

 

[heymccall]

"Hydraulic lockout appears to function properly"

Just couldn't post a serial number, could you? Bulletins, tech info, and even basic parts are 10 thousand times easier to research when a serial number is provided :bangshead:

Cat publications are searchable by serial number, not model number, and in this case, there are 7 different prefix, and, due to production demands, there are many parts that do not interchange between the 7 prefix.

Why not see if the lockout switch is actually working?

 

[Broke315CL]

Okay I'll get the serial number Saturday when I'm with the machine again.

You are right that I should actually test the lockout switch, I only say it appears to be working because if I cycle the key quickly with it in the raised lockout position the starter will bump once as described above, if I lower the lockout lever there is nothing happening when I turn the key quickly, so I assumed this meant it was in working condition. I'll look for the diagnostic test for the lockout lever in the manual and do that Saturday as well.

Thanks again.

 

[Nige]

HMC is correct. Yellow Iron works on Serial Number, not model or model year, or anything else. Especially in the smaller machine line where there may be multiple S/No prefixes for the same model. You're lucky in that there are only seven, I've seen models with over 50 different prefixes.....

I assume you have a paper manual. Is the electrical schematic a big fold-out job about 3ft x 2ft in size..?
It might actually be two sheets printed both sides, 4 pages in total. On Page 1 are line drawings of the machine with callouts of component locations. See below which without a S/No may not be the actual schematic you are looking at. Just to give you an idea. On a paper version it will obviously be larger than shown, on a pdf you can magnify it to whatever size you want, hence my offer above. Who knows, you may be lucky and there is one of the new-style pdf files available for your machine. They can run up to 20 pages.

 

[Broke315CL]

Yes I have the large multipage fold out schematics in the back of the paper manual binder, I tried using the location section but the G7 callout for starter relay didn't yield much help, I was confused because they only show one side of the machine too. I think, cautiously, that the starter relay might be under the bolted cover for the fuse box near on the left hand side of the machine near the batteries. There is a large white wire coming from the solenoid which i think runs up from the bottom under that cover.

I understand that there are many slight variations among the many different versions of the same model machine, but if we could speak in general terms for a moment, I would like to test for power to the starter relay and solenoid, starting with the solenoid and work backwards towards the key. I know the starter has power from the battery and I know the key has good power so I need to check the inbetween stuff.

This starter looks a little different than the automotive units I'm used to. The starter/solenoid is a Perkins #2873K406, has the large red wire from the battery, the large ground strap to chassis, a medium white wire i'm guessing comes from the starter relay and then a small wire that may be a control wire?

I have tested the large red wire to the starter for voltage and resistance and it looks fine. I would like to test the other wires, shouldn't the white wire get voltage when the key is in START position? I'll test the ground strap connection to chassis after cleaning it. What about the small wire, anything I should measure for that one?

Thank you guys very much for your help with this matter.

Okay, I'll check in tomorrow with the actual serial number.

 

[Nige]

How about 2 pieces of info to kick start this.?
What is the Cat Publication # of the paper schematic you are using.? You will find it in the top RH corner of Page 1. RENR7696 by any chance.?
On the schematic page what part number is given for the start relay..?

 

[heymccall]

Nothing exotic there. Just a denso starter.
And, yes, in the main power panel, the larger gauge white coming off a relay is the crank wire.
The main power relay has large red in and large purple out.
When you go to crank, the large white wire goes hot (24v) to the starter.
At key on, and crank, the main power relay out purple should remain hot (24v).

 

[Broke315CL]

Nige, I'll get those numbers for you tomorrow along with the serial number. Then will have more specific info to go on. I appreciate it.

Heymccall, IDK Something about the starter assembly looked funny to me, like it was backwards, most of the starters I have worked with have the starter cast to mate to the block and a little solenoid off the side, this one seems like the starter is off to the side and the bigger solenoid inline with the gear, just a bit different than what I am used to. I know it functions the same.

Anyway, I will check to make sure those wires in the panel are testing correctly, that's a big help I was unsure of where to go, this helps.

Thanks very much again, I will update tomorrow.

 

[Broke315CL]

Okay some good progress this morning. I tested the start circuit completely and once I located it I found a fault in the starter relay, there was good voltage going to it but nothing come out of it when the key in the start position. I was able to bridge the contacts of the supply and output wires and turn the motor over like that, it started and ran fine!

I got the part number off the starter relay and will order a new one, at least we can move the machine to a better location in the meantime.

There was some wiring in there that is not OEM, you can see some extra wires had been clipped off the relay and there is a small automotive 5 pin relay hanging from the power supply line and attached to the body of the starter relay, no idea what they were doing with that, I removed that and will clean up the wiring when installing the new part.

I didn't have a chance to get the schematics but I can find it another time, where is the serial number located on the machine exactly for future reference?

Thank you guys for your guidance and help in resolving this, big help to me and helpful to our company.

 

[Nige]

Starter relay hidden in plain sight then..?

where is the serial number located on the machine exactly for future reference?

Right side of the machine. Front corner of the upper frame, directly above the tracks.

 

[Tristan05]

Okay some good progress this morning. I tested the start circuit completely and once I located it I found a fault in the starter relay, there was good voltage going to it but nothing come out of it when the key in the start position. I was able to bridge the contacts of the supply and output wires and turn the motor over like that, it started and ran fine!

I got the part number off the starter relay and will order a new one, at least we can move the machine to a better location in the meantime.

There was some wiring in there that is not OEM, you can see some extra wires had been clipped off the relay and there is a small automotive 5 pin relay hanging from the power supply line and attached to the body of the starter relay, no idea what they were doing with that, I removed that and will clean up the wiring when installing the new part.

I didn't have a chance to get the schematics but I can find it another time, where is the serial number located on the machine exactly for future reference?

Thank you guys for your guidance and help in resolving this, big help to me and helpful to our company.

Good day,

Im having issue with our caterpillar 325c. At first we had some issue and active error 69:581-05, no power when moving the bucket and the engine shutting off when giving more hydraulic pressure, after searching and troubleshooting I found that the one switch with 12wires connected are broken, before changing the parts that the machine can start easily, then after 1 week when I get the parts I changed the switch the machine will turn on and you will heard the fuel pump but it wont crank at all.

 

[skyking1]

start your own thread, please.
Describe the problem in the thread title and put the serial number in the first post.
Welcome to the forums.

 

[Nige]

start your own thread, please.
Describe the problem in the thread title and put the serial number in the first post.
Welcome to the forums.

Agreed. If you are in doubt about how to create a thread, click this LINK