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Starting Problem - Bobcat 753

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Help… I lose more husband points everyday this sits in the yard!

I bought a Bobcat 753 that has been sitting idle. Installed new starter. Panel comes up and I get 3 of 4 lights (Traction/Parking light does not come on). No Trouble Codes are displayed. Unit has 3,150 hours. When I turn the key, the solenoid attached to the throttle lever moves. Starter does not engage.

Wheels are locked, bucket is locked down position. Mucking with relief valve did not seem to do anything.

Starter will spin engine when I jump it.

Can’t find fuse block to check fuses. Feel really stupid…

I have a service manual on order but it sure would be nice to be able to move this thing from where the wrecker dropped it.

Thanks for any advice!
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Fuse block is located just below your knees when you are sitting in seat.... Down toward the foot controls. Access door about 6 inches wide by 2 inches tall. You say that you are able to crank motor if you jump it? Are you jumping directly to starter or to battery? If you are jumping directly to starter terminal you should be able to manually hold fuel solenoid in run position and be able to start it. When you turn key switch on and glow plugs have cycled do you hear three beeps from the panel? If you do hear that press and hold the light switch "on". If there are codes they will show on the hour meter. Hope some of this is of help to you...... Losing husband points sucks! Paul W
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
I'll get back into it at first light.

Thanks for reply! That helps a bunch. I was able to get to the codes and it said "No code". That gave me a warm fuzzy feeling.

Normal battery hookup. Jumped big power lead at starter to one of the small brown wires. (both small wires are brown, one is slightly thicker than other. Not sure which terminal they are attached to. Have one on each)

Was getting some beep action but don't remember sequence. I'll pay more attention. Looks like all the indicator lights flashed.

What is supposed to happen when you press the Park Brake switch? I don't hear anything and my left panel led stays off.

Again thanks for the help!
 

Countryboy

Senior Member
Joined
Jun 8, 2006
Messages
3,276
Location
Georgia
Occupation
Load Out Tech. / Heavy Equipment Operator / Locomo
Welcome to Heavy Equipment Forums Ralph! :drinkup
 

Orchard Ex

Super Moderator
Joined
Jul 6, 2005
Messages
1,051
Location
Southern MD
Is the lap bar switch working? I've seen them get picky about that, but I can't remember if they will start without the bar down.
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Lap Bar...

The status LED lights up when the bar is down. I don't have the electrical diagrams but you'd think the same signal would tell the controller the bar is down (and I'm ready to do a backward summersault like the guy on the YouTube video. -5 husband points for letting my wife see that one...)

Do you know what is supposed to happen when I press the Traction/Parking toggle switch? Can you start the engine without all 4 lights. The operating booklet I found was not clear if it blocks the engine or just the bucket controls.

I'll check my fuses tomorrow and maybe I'll get lucky.

I've got a lot to learn! Thanks for your help.
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
OK, this is really starting to bother me so I went out to the machine shed and puttered around with mine..... Mind you now, its about 12 degrees and the wind is blowing at 11 MPH so says my computer! Cold.... Mine is a S150 but that is just basically a 763 updated a little bit. It starts with the lap bar up or down. The 'Traction lock override' button on the left overhead console will allow the machine to be moved while the lap bar is in the up position. The parking brake button located in the very center of the overhead console lights up when pushed and I can hear a clunking sound under the seat, stop pin for the drive motors I think. I generally never use the parking brake switch as the machine will not move after the lap bar is raised. Paul
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Ralph, I re-read your last post and remembered (forgot?) to post that my loader controls have a switch all their own.... Does yours? Paul
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Status on starting... Seat belt idiot light?

Paul, thanks for the info! 12 degrees in the dark, cold, and snow is above and beyond! Sounds like you got blasted by the storm. Meant to reply sooner but like my skid steer, my internet connection was down.

Found fuse box and did a once over. The fuses and relays all seem to be working. Swapped the relays for good measure and nothing changed.

My big red Traction/Parking switch lights up for brake on position. Don't hear any noises when I flip the switch to indicate brake is released. Wheels are locked.

The LEFT UPPER CORNER on my 753 looks to be the updated version on this series. I see 2001 on the EPA sticker on the engine.

The upper row has switches for 1)lights 2) Bucket position 3) High flow 4) Max / Variable Flow 5) Aux Pres Release

Next row 1) Green Press to Operate 2) Seat Bar LED 3) Lift Tilt Valve LED 4) Traction LED (This one will not light up, the other LED's will come on)

Third Row Traction lock overide

CENTER PANEL Parking Prake switch

RIGHT PANEL Bunch of idiot lights. SEAT BELT LIGHT is ON. I don't see any wires to any sensors on the belt. Ends are clicked. I'm wondering if this is tied into Interlock control.

What happens on start...

Bar Down
Key to On 1 Beep... Glow plug countown...
Key to start Clicking from back (throttle) No sound from starter

When I first tried, I got a 3 Beep series but have not been able to duplicate it again.

I'll move up the trouble shooting chain and see if I can find the right cuss words to make it work. Heaven forbid that I have admit defeat and resort to the manual...

Thanks again for the help and braving the cold to get that info. Have a Merry Christmas!

Ralph
 

Tacodriver

Well-Known Member
Joined
Nov 4, 2006
Messages
105
Location
East Kootaneys
Occupation
Yarder op, hoechucker, lowbedder etc..
We have a 753 of approx same vintage I think and I know it doesn't matter if the seat bar is up or down to start. Check to see if starter soleniod is getting power from the signal wire. Good luck. Or just put lights on it and call it a christmas deceration.
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Ralph, Sounds like your description of the upper left and right instrument panels is just like mine.... Here's my starting sequence, Butt hits seat. Lap bar down. Key on, glow plug countdown. Start engine. Left hand reaches up and presses "Push to operate loader" button. Game on! My T200 is exactly the same. Just for grins and giggles open your engine door and jump from the large red wire on the solenoid to the "S" terminal on the solenoid. This will be doing exaxctly the same thing as turning your key switch to the "start" position. If engine cranks you should be able to manually hold fuel shutoff solenoid in the run position and start the machine. Dont know if that will do anything with your park brake switch in the cab but atleast its a step in the right direction when your wife asks about her lawn ornament..... "Honey, ive got it running so i'm closing in on the problem...Just a little more time...."
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Christmas lights...

... Or just put lights on it and call it a christmas deceration.

I can't calculate how many negative husband points I'd get for that!

The starter came in a box so I may have hosed up the wiring. I think I got the big red ones right. There were two small terminals on the soleniod and two small brown wires so I put one one each. I'll check for a signal.

Thanks for the insights. Actually I really like the Christmas light idea. I just hate to make all the neighbors jealous. I'm the only guy with a beat up skid steer in his front lawn. Like how cool is that...

Ralph
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Ralph, there's 4 wires on the starter..... Im color blind so I wont tell you what colors I see but I did notice that all the wires are different sizes so here goes.... Biggest one (which I know to be red) comes direct from battery and connects to large post on starter motor. Next biggest one comes out of wire loom and connects in same place. It is about the size of a pencil. Next smallest wire connects to small stud on engine side of solenoid and smallest wire connects to stud on engine bay door side of solenoid. Hope that helps out..... There were some numbers on the smaller wires but I couldnt make them out in the poor lighting...... Paul
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Got manual!

Thanks for all the tips. Manual showed up under the tree. Mailman delivered it late in the day and my wife wrapped it up. That manual could choke a horse. Printed on both sides. At least there are a lot of pictures!

Just a quick look seems to indicate the solenoid switch is bad. We'll see...

Again, thanks to everybody who posted.
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
I think that if the solenoid where bad you wouldnt be able to crank the motor at all. If you jump to the input terminal on the solenoid it should spin engine. Paul
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Starter...

I hope to get back into it tomorrow.

She'll spin the engine if I jump the terminal nearest the back to the power post. The manual is a little confusing on which is the S or the M terminal. The next page with a clear picture from a good angle labels them S & R.

Hopefully that will all sort out. The other fun thing on the list is to drain the fuel tank. I'm sure the old stuff pretty skanky. Picked up a new filter and fuel today. Sure would love to move that thing onto the driveway closer to my tools!
 

TALLRICK

Well-Known Member
Joined
Apr 28, 2007
Messages
195
Location
florida
If any of my neighbors had a skid steer sitting on their lawn I would give them bonus points! I was thinking of a fun computer problem with a 763 I was trying to fix. The wiring harness had been damaged, and power was intermittent. After detting that to work the glow plugs would not turn on. I am sure that after a good look at the manual, and some time to think, you will get it. Hopefully you got a good deal on the Bobcat and will be enjoying it for years to come!

There's more than one way to tow it to a better spot!
 

Paul W

Well-Known Member
Joined
Jan 19, 2007
Messages
49
Location
Ackley, Iowa
Ralph, my offer from a few days ago still stands. I'll be busy until midafternoon tomorrow but your more than welcome to call.... your really close to getting it to run..... If it cranks you can reach up to the injection pump and push the fuel shut-off lever to the right and it should start..... Paul
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Status report...

Starter has issues but we were able to jump it to work through everything else. It's looking like the injectors need help.

Spent $150 to have a mechanic make a house call. Fun to watch somebody who knows were to apply brute force and where not to. It's a great feeling to know that the engine was not toasted.

Even though the glow plugs checked out with the meter, they ends were coated and he really had to work to get them out even after they were loose. I'll bring the injectors to a shop tomorrow. Can't wait to get them back and crank it over!

Again thanks to everybody who posted. The mechanic was pleased to have the machine to the point where he could jump right in and do his magic.
 

Ralph

Active Member
Joined
Dec 22, 2007
Messages
34
Location
Wilmington, NC
Bingo! It started. What do you know about blow by?

Got it engine to fire up. Sweet sound!

3 of the injectors were fouled. Still had trouble with the refurbished injectors. Added some oil to the cylinders through the glow plug holes. That must have helped build the compression (cranked with plugs out to blow out the excess). Put it back together and it finally fired up.

Sounds great, Not much smoke, but I've got a lot of blow-by out of the vent pipe. Hoping it something would seat after running it awhile but so far, no change.

Hydraulics work great. Did not see any leaks. I moved it out of the yard. Big relief!

Got lucky this time, but it will be along time before I buy a piece of equipment that has been sitting in a goat field! The longer it sat in my yard the more I was feeling like a goat...
 
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