• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

JCB Backhoe Starter Assistance

Steve Best

Steve Best

Active Member
Joined
Aug 2, 2019
Messages
26
Location
Halifax Canada
Occupation
Millwright, machinist, instructor
Voltage drop with no load should be "none". Same as at battery.
Voltage usually drops to 9-10 volts or so at the starter while cranking. Less if connections are bad.
Need lots of battery too. Most guys running a car battery, no good for cold weather.
Block heater is a must in cold weather.
I do not have 110v power so I use a propane Tiger torch to heat the oil pan for 15 minutes.
20201231_114257.jpg
Here is the torch heating up to get lug nuts off. Just hot enough to melt some wax on them.
Keep far enough back to not burn paint or boil oil. Goal is warm to the touch. Not smoking.
Engine will crank easy and start when it is warm to the touch.
 
E

edgephoto

Senior Member
Joined
Aug 13, 2019
Messages
730
Location
Stafford, CT
Steve Best said:
Voltage drop with no load should be "none". Same as at battery.
Voltage usually drops to 9-10 volts or so at the starter while cranking. Less if connections are bad.
Click to expand...

Actually voltage drop is measured in a functioning circuit. What you are describing is measuring potential voltage. This is not voltage drop.

Voltage drop is how to find small resistances in high current circuits.

When the circuit is not operating measuring voltage does not really tell you much other than you have potential. But you are measuring across an open circuit so if you have corrosion(resistance) this test will not help you determine that. no matter how much resistance is in a circuit you will measure full potential across an open circuit. This is why you measure 12 volts at the starter when not cranking but then when you try to crank you might only have 8 volts at the same points. The resistance comes into play when current is flowing not when it isn't.
 
W

woodfirst

Well-Known Member
Joined
Mar 13, 2011
Messages
62
Location
nh
Thanks Steve and Edge. Battery load tests out fine and is a 1000cca heavy duty equipment battery I get a drop to approx 9 volts at battery when starting and virtually the same at the starter connections, It was a cheap replacement starter installed approx 3 years ago and has always cranked slow when cold. Thats why I wanted to try a gear reduction starter. Mine is also in a barn with generator power and when cold have always had to plug it into a electric oil pan heater for an hour or
 
5

56wrench

Senior Member
Joined
Dec 4, 2016
Messages
2,106
Location
alberta
ya, X2 for the coolant heater. it is more important than an oil pan heater. when using an oil pan heater, it would have to be plugged in for about 5 hrs to actually warm up the entire oil let alone anything higher than that in my opinion. the best is a combination of both and to save power use a timer on the power supply
 
W

woodfirst

Well-Known Member
Joined
Mar 13, 2011
Messages
62
Location
nh
Agreed, the challenge is its in a shed w/o power 1/4 mile form the nearest power source. Heating it 5 hrs in advance really isn't practical with the generator. Also could not find an easy to fit coolant heater for it. The engine is really stuffed in . Thanks
 
T

Tinkerer

Senior Member
Joined
May 21, 2009
Messages
9,366
Location
The shore of the illinois river USA
Where there is a will there is a way. :)
There has to be a place you could mount a tank style coolant heater. Even in the cab. If it has one.
A 1500 watt heater will warm that engine very quickly.
The coolant doesn't need to be summer time warm either.
If you feel brave make a sheet metal enclosure for the lower part of the engine and put a propane weed burner under it.
 
S

stinky64

Senior Member
Joined
Feb 25, 2017
Messages
887
Location
java center ny
Occupation
big truck wrench/fixer of things
stinky64 said:
If only cold weather issue, do you have and use any kind of block heater? makes a world of difference up here in the snow covered states...
Click to expand...
Small torpedo heater w/generator power if strategically placed would probably work as well...Draws a lot less juice than block heaters if grid power not available.....
 
Last edited:
E

edgephoto

Senior Member
Joined
Aug 13, 2019
Messages
730
Location
Stafford, CT
woodfirst said:
Thanks Steve and Edge. Battery load tests out fine and is a 1000cca heavy duty equipment battery I get a drop to approx 9 volts at battery when starting and virtually the same at the starter connections, It was a cheap replacement starter installed approx 3 years ago and has always cranked slow when cold. Thats why I wanted to try a gear reduction starter. Mine is also in a barn with generator power and when cold have always had to plug it into a electric oil pan heater for an hour or
Click to expand...

Your battery is dropping to 9 volts when cranking? That battery is not good. Get yourself a good battery that won't drop below 10 volts during cranking and you will find your machine starts much better. Gear reduction starters are awesome and if you need to replace a starter I would suggest one.

You said it load tests "fine" but then you state the voltage is 9 volts during cranking. That is not fine. What are you using to test the battery? I have found many of these new capacitance battery testers and chargers do not always diagnose a weak battery. The best way is fully charge it, put 1/2 of the CCA of the battery on it as a load for 10 seconds. This removes the surface charge. Then do 50% of the CCA again for 15 seconds and monitor the voltage. if it goes below 10 volts the battery is junk.

I have been doing this stuff for 35+ years with automotive and light truck. My experience is the Midtronics battery diagnostic chargers and handheld testers are good but not always 100% reliable. The old school carbon pile works the best.
 
W

woodfirst

Well-Known Member
Joined
Mar 13, 2011
Messages
62
Location
nh
Thanks Edge, you may be right I have an old school battery load tester with the heating filament and it stays in the green on the scale for the cca when I test it for the prescribed amount of time. In my JCB service manual it states that if(Big if) the battery is good and drops excessively(at the battery) when engaging the starter then the starter is likely faulty.
 
E

edgephoto

Senior Member
Joined
Aug 13, 2019
Messages
730
Location
Stafford, CT
Is it one of the handheld types looks like a cheese grater? If so, those only load it to about 100 amps.

Can you get a vehicle near the machine? If you can, then use jumper cables to connect a second battery for testing purposes. With jumper cables connected and the machine cranking measure the battery voltage. If at 10volts or higher you will know if your starter is working well.
 
5

56wrench

Senior Member
Joined
Dec 4, 2016
Messages
2,106
Location
alberta
about 25 years ago i got a screaming deal($700 for a 1400$ machine) at a GM dealer closeout auction on a Snap-On digital AVR with manual carbon pile and 24v capacity. i've load tested batteries that failed when the other style testers said they were good. the trouble is that most auto parts stores only use the cheap crappy style to warranty-test batteries
 
W

woodfirst

Well-Known Member
Joined
Mar 13, 2011
Messages
62
Location
nh
I wanted to post a follow-up to this thread. I ordered the gear reduction starter that Skata found on ebay. Cost was only $136 so although the picture showed iIn a different orientation than the original I figured I would risk it. It did match the original JCB part number. When it arrived I noticed it was half the size and half the weight of the original. Looking at them side by side, I regretted ordering it as it looked way too small. It went in under 5 minutes as it gives much better access to the mounting studs. The only real issue is that the solenoid is orientated toward the right side of the starter body versus above it so I had to lengthen a couple of wires. In terms of performance it was night and day. It spins the engine in 25 degree weather like a summer day. It has never cranked so easily. While the jury is still out on long term performance so far this was a no brainer. Thank you to everyone for their help
 
E

edgephoto

Senior Member
Joined
Aug 13, 2019
Messages
730
Location
Stafford, CT
I used to have a Jaguar V12. They were notorious for cooking the starters. I replaced the starter with a gear reduction model. It never cranked so fast and started nearly instantly. Amazing how small and light they are and amazing how much power they pack. It is a worthwhile upgrade.
 
S

skata

Senior Member
Joined
May 10, 2007
Messages
1,541
Location
midwest
woodfirst said:
I wanted to post a follow-up to this thread. I ordered the gear reduction starter that Skata found on ebay. Cost was only $136 so although the picture showed iIn a different orientation than the original I figured I would risk it. It did match the original JCB part number. When it arrived I noticed it was half the size and half the weight of the original. Looking at them side by side, I regretted ordering it as it looked way too small. It went in under 5 minutes as it gives much better access to the mounting studs. The only real issue is that the solenoid is orientated toward the right side of the starter body versus above it so I had to lengthen a couple of wires. In terms of performance it was night and day. It spins the engine in 25 degree weather like a summer day. It has never cranked so easily. While the jury is still out on long term performance so far this was a no brainer. Thank you to everyone for their help
Click to expand...
That's good to hear. Since it's a gear reduction starter, it doesn't need such a big motor as the oem direct drive. This is where size Doesn't matter!
 
E

edgephoto

Senior Member
Joined
Aug 13, 2019
Messages
730
Location
Stafford, CT
skata said:
That's good to hear. Since it's a gear reduction starter, it doesn't need such a big motor as the oem direct drive. This is where size Doesn't matter!
Click to expand...

Well also these starters use permanent magnets instead of windings so they can be smaller. Combine that with the gear reduction and we have a winner.
 
hookedondiesel

hookedondiesel

Senior Member
Joined
Jan 24, 2013
Messages
503
Location
Sault Ste Marie Ont. Case 1835C
woodfirst said:
I wanted to post a follow-up to this thread. I ordered the gear reduction starter that Skata found on ebay. Cost was only $136 so although the picture showed iIn a different orientation than the original I figured I would risk it. It did match the original JCB part number. When it arrived I noticed it was half the size and half the weight of the original. Looking at them side by side, I regretted ordering it as it looked way too small. It went in under 5 minutes as it gives much better access to the mounting studs. The only real issue is that the solenoid is orientated toward the right side of the starter body versus above it so I had to lengthen a couple of wires. In terms of performance it was night and day. It spins the engine in 25 degree weather like a summer day. It has never cranked so easily. While the jury is still out on long term performance so far this was a no brainer. Thank you to everyone for their help
Click to expand...
Glad to hear this, can you give me your original JCB starter number and the link you got your new starter?
 
W

woodfirst

Well-Known Member
Joined
Mar 13, 2011
Messages
62
Location
nh
What model and year is your machine? You may want to call your local JCB dealer and see if there is a superceeded number? The pics online look identical to 714/29500
 
You must log in or register to reply here.
Top