DX 33 Starting Problem Fixed

[Jerry/MT]

And of course as volts go down, current goes up. QUOTE]

Can you explain what you mean by this statement?

 

[ENTS]

Jerry,

I too am curious. In a pure resitive circuit, E=I*R. With R constant, and E goes down, I goes down. RE: 12V and 4 ohms = 3 amps. If 12V goes to 10V and R is still 4 then I = 2.5. Maybe it's the battery that delivers more current as the volts go down:confused2: I'm sure someone will weigh in here soon especially if I'm wrong.

 

[thclimer]

I'm not electrically astute but I believe this is the equation which applies in this situation:

P = I * E

Where P = Power (watts), I = Current (amps), E = Voltage (volts).

For example, if you have a 12 volt battery in a circuit with a device which uses 96 watts then the current running threw the device would be:

P = I * E or I = P / E

96 watts = I amps * 12 Volts or I amps = 96 watts / 12 Volts

I amps = 8

So if your power requirement (watts) does not change but the battery voltage drops to say 10 volts, then the current required would be:

96 watts = I amps * 10 Volts

I amps = 96 watts / 10 Volts

I amps = 9.6 or an increase of current by 20%

This why fuses tend to blow when the battery voltage drops.

 

[jinman]

So Tim, by that logic, if the voltage drops to 1 volt, you'd be drawing 96 amps.:shocked:

When the voltage drops in a circuit of a given resistance, the current also drops and the overall power is less. That's the way it works. For a given resistance, changing the voltage also changes all the other values.

 

[thclimer]

Hey Jim,

I was hoping someone with a better understanding of electricity like you would read this post.

So are we talking about V (volts) = I (amps) * R (ohms) like in Fred's example

12 volts = I amps * 4 ohms

I amps = 3

And if the voltage drops to 10, then the current will drop to 2.5 with the resistance being constant.

So in our case of blowing fuses when we are trying to start our tractors it not really because our batteries are weak, but because the resistance in the circuit has increased, thus drawing more current?

 

[jinman]

I think it's possibly the additional current by the inductive load of the starter motor and the interaction of the armature and fields. An inductive load initially has high resistance until the magnetic field is maximumized and then effectively low resistance. If the motor doesn't turn, the load goes to maximum and stays there. Essentially, because of lower voltage, the motor doesn't have sufficient torque to turn the engine at normal speed. Starting current is high for a longer period of time, causing even a slo-blow fuse to pop. If the battery is hot enough to get the starter and engine spinning rapidly, the full torque requirement of the motor is reduced, allowing it to spin at higher rpm but not in a steady high current state. This is a bit of an oversimplification, but I don't think it's too far off.

 

[djradz]

I think it's possibly the additional current by the inductive load of the starter motor and the interaction of the armature and fields. An inductive load initially has high resistance until the magnetic field is maximumized and then effectively low resistance. If the motor doesn't turn, the load goes to maximum and stays there. Essentially, because of lower voltage, the motor doesn't have sufficient torque to turn the engine at normal speed. Starting current is high for a longer period of time, causing even a slo-blow fuse to pop. If the battery is hot enough to get the starter and engine spinning rapidly, the full torque requirement of the motor is reduced, allowing it to spin at higher rpm but not in a steady high current state. This is a bit of an oversimplification, but I don't think it's too far off.

Nope. Not an oversimplification at all Jim. Right on, except for the use of the term "high resistance" in the second sentence, as the correct term is high impedience which reflects both the resitive and inductive loads. As you note, the high current stays for much too long (due to not turning, or the operator continuing to hold the key) and the fuse heats and blows. The fact that the current is initially slightly less due to the low voltage (as you and others have noted - this is Ohm's Law) is negligible and far outweighed by the substantial length of time. In fact, if the fuse didn't blow, there's a good chance the motor would overheat and fail.

 

[jinman]

Nope. Not an oversimplification at all Jim. Right on, except for the use of the term "high resistance" in the second sentence, as the correct term is high impedience which reflects both the resitive and inductive loads. As you note, the high current stays for much too long (due to not turning, or the operator continuing to hold the key) and the fuse heats and blows. The fact that the current is initially slightly less due to the low voltage (as you and others have noted - this is Ohm's Law) is negligible and far outweighed by the substantial length of time. In fact, if the fuse didn't blow, there's a good chance the motor would overheat and fail.

Thanks Duane, and you are exactly correct that impedance is the correct term when referencing inductive loads.:thumbsup:

 

[SteveInMD]

The fuse blowing problem with these tractors from the OP is much worse when the battery is even slightly below full charge (and I don't mean near dead, just slightly off peak). Also the problem did not show up for a few years after the tractors were new. I believe the original circuit also results in a somewhat slow crank.

The theory was that over a few years the safety switches became less than perfect connections resulting in less than 12 volts at the solenoid. Perhaps this caused it to throw out slowly??? I know my tractor would even blow a 15 amp fuse.

I don't know what the answer is. I do know that adding a relay solved the problem. (I replaced the key switch before doing this mod. and I still had the issue.) The starting circuit now draws less than 7 amps, the crank speed is faster, and it always starts. Jiman's explanation sounds reasonable. I am curious however why after the modification the tractor has much less trouble starting with a low battery than before.

 

[Fanlo2300]

My 2003 DX-33 did blowed many 10 amp, fuses after I bought it last summer.

I never happened again after I installed a new battery.

It even started A-1 last Saturday after sitting for a week in an unheated garage at -20 C (with a 15 min. preheat with the block heater).

 

[durf 700]

Well, I'm no expert at drawing circuit diagrams, and PowerPoint doesn't seem to supply standard circuit diagram objects to insert, but I did what I could. The attached PDF file is three pages showing the original circuit, the completed alteration to the original circuit, and finally the new starting circuit. There are things missing from the diagram, such as the original fuse, but since you don't touch that part I left it out to keep the drawing simple. The circuit is more complicated than I have shown, but it does show you what you need to know to complete this fix. I tried to use the same wire colors as Jsheds describes where I could, but the white wire was hard to draw on white paper. Let me know if this needs any clarifications and I'll do what I can.

Thank you so much!!!!! I have been fighting with this clicking issue and it has been getting worse for the last several months!!!! I replaced the starter, battery terminals and cleaned up many grounds... I was just about to give up and call up my local New Holland dealer when I stumbled over this relay solution. I called my local NAPA store and gave them the relay and relay plug with wires part numbers noted above.. and as of 2016 the part numbers are still in use!!! I installed in about 20 minutes right at the starter with the wires provided on the plug that can be purchased with the relay. I then simply slid the relay up in the bottom of the black plastic beside the brake pedals on my 2003 TC 45 DA. its protected from the weather because there is a one inch think foam seal that you can feel inside the black plastic. This saved me a ton of time not having to take apart the tractor and bolt up the relay. I simply installed a new male end on the wire that you need to hook to the existing wire that you remove from the solenoid, then a female end to the wire that you send back to the solenoid which plugs back onto the solenoid.. then 2 5/16" round wire ends.. 1 for the starter wire and 1 for the ground which I grounded at the starter bolt with the other grounds by the brake pedal. This works perfectly!!!! best 50-60 dollars I have spent in a while!!! Everyone with this issue should try this right now!!!!

thanks

 

[rickyc31]

I am having this issue with my DX33. I cannot see any of the pictures y'all have attached. I am using iPhone 6s Plus. We do not have access to high speed internet where we live. I have tried opening with chrome, Safari and opera mini. Any suggestions? Thanks in advance.

 

[motownbrowne]

I am having this issue with my DX33. I cannot see any of the pictures y'all have attached. I am using iPhone 6s Plus. We do not have access to high speed internet where we live. I have tried opening with chrome, Safari and opera mini. Any suggestions? Thanks in advance.

You should also search for the same issue with the new Holland tc25, 29, and 33 tractors, which are the same machine painted blue. Also, I'll send you a PM about a service manual.

 

[Halftrack]

I just fixed mine so lets see if I can talk you through it. You need a 4 blade (or spade) 12 volt relay. Two blades control the solenoid circuit and two blades are the switch circuit, normally open. I put everything near and above the starter. Unhook the ground or positive cable from the battery. Unfasten the red wires from the top of the starter. There is a plastic shroud under those wires which will come off and behind it is a purple wire on a spade which energizes the starter solenoid. The purple wire will go on one side of the new solenoid circuit and the other side will be a new 14 ga wire to a GOOD ground. One side of the switched circuit will be a 14 ga wire from the terminal where the red cables attach to the starter with a 10 amp inline fuse and the other side will run to where the purple wire came from on the starter. Put it back together in reverse order and attach the battery cables and that's it. I kind of cable tied the solenoid above the starter.

 

[thclimer]

I've uploaded another copy of the wiring diagram, this copy has some notes with it, hope you are able to view it.

 

[Little red 33]

Hi, new guy here I have a DX 33 with the same intermittent starting issue I have the bulletin from my dealer and the parts but no pictures and for some reason I can't access the attached images what am I doing wrong?
Thank you Troy

 

[rickyc31]

Troy, I had the same problem. I finally solved it by loading it on my laptop computer. All images were visible there. I was previously trying to load on apple devices, iphone and iPad, neither or which worked. I had to purchase a wifi hotspot. Best deal in my area was they straight talk. Purchased device at Walmart for about 50.00 and got 5 gigs of data for 60 days for 45.00 or 50.00.
Also, I did the fix, but was still having an issue with starting when hot, I then purchased a new battery, and she has been running great since then. Even though my battery was testing good at auto parts house, I went ahead and purchased a new battery and that solved the remaining issue.

 

[Little red 33]

WOW very quick reply Thank you rickyc31 I was using an iPad, switched to laptop and there they are. Great images thank you guy

 

[jdri1150]

The Napa relay I purchased shows part # AR276
I also purchased a plug with 4 wires that plug into the relay part EC23. You do have to make sure the 4 wires are in the position to contact pins 30, 85, 86, 87 (and not 87a)
There are detailed pictures on this site from Jsheds. For those interested a search under TC33DA-Starting problems will furnish good instructions. I basicly followed the instructions that others furnished on this site.
(1) Relay installed under plastic on left side down low in a vacant hole in the steel plate. Attached the inline fuse 30A on the engine side on the same bolt.
(2) Ran the wire from pin 30 thru the inline fuse and attached at the bolt holding the battery positive to the starter.
(3) Ran the wire from pin 85 to ground. I attached to a bolt under the clutch area that holds a hydraulic line. (need a loop end here just like what is needed to attach at the starter.
(4) Unplugged the white plastic connector from the back side of the starter solenoid and cut it off along with a few inches of wire. Connected this white connector to the wire from pin 86 and plugs back to the solenoid.
(5) Take the cut wire that previously went to the solenoid and connect it going to pin 87 .
I saved pictures and instructions on what others posted and printed them out for instructions to follow.

Hello. I am trying to purchase the parts you have in your thread to resolve my TC33DA starting problems. Are the 2 parts the only 2 needed? I see in your step #2, it states to run wire thru inline fuse? Is that another part to purchase?

 

[jdri1150]

Cardenharry,
Thank you so much for help!! Would you happen to know the part # for the plug with 4 wires that plugs into the relay part EC23? Are the wires different lengths?