1872 hydrostatic- moving tractor that is not running

[Gary James]

I'm hoping this is the right place to post. I've been trying to get the answer of whether I can push an 1872 while it is not running. I've gotten different answers and a lot of times I hear from people who work on them say that there is a lever on the transmission to disengage. I see no lever. I have scoured the manuals and there is no mention of it. I was asked if it has a shaft and if it does, I shouldn't move it. I've been worried about moving it because of the fluid pump.

I've had several occasions where the fuel pump has given out, or other situations and I don't want it sitting out in the open or the weather.

Insights? Many thanks!

 

[1811Cub]

You can safely push it for a few feet at no more than walking speed. That model has auto pressure relief valves.

 

[Doug Rusk]

What 1811 said. The older models have the lever these do not.

 

[grozar]

How long has the tractor sat without the engine running?

 

[Gary James]

I had tried to post to this a few weeks ago but for some reason it didn't post.

For 1872 afficionados- I had got my tractor to run a couple of times. I'm sure you have read about gasoline getting into the crankcase. This is the second time for me. Carburetor and fuel pump. I had bought cheapie knock-off carbs. I finally went with iSaveTractors for the carb. As for the fuel pump, that thing has the most cockamamie method to add the attachemnts. A circular clip that is almost impossible to press into the tabs. Even a snap clip tool is iffy. Finally I got a clean install. Had to drain the oil twice until I got a carb that would not overrun into the cranckcase. I finally got both on and ready to run.

Sat down to start my baby up- broken ignition switch. I have a feeling the off and on starting might have been inside the switch. Got one on order.

Gotta keep my baby running!!!!!

 

[Gary James]

Now I have another conundrum. There is a replacement switch for 725-3026, now 925-3026. The wiring is different. Has anyone had to replace the switch? Is there a revised wiring diagram?

I'm referencing the diagram on this post.

https://www.ihcubcadet.com/threads/1872-electrical-problem-help.1661/
925-3026 diagram....

What happens to the run wire?

 

[1811Cub]

I have bought the 925-3026 current issued ign switch for a couple of my tractors. They are identical to the older 725-3026 switch. MTD went through and updated most of their part numbers using a "9" instead of a "7" several years ago. For the most part, the parts are the same, just the different part number.

On the gasoline powered 82 series era tractors, there are only two different ignition key switches out there. One is for battery powered ignition (read: points)(925-3021), and another for magneto ignition that uses a kill circuit. (925-3026).

On this diagram, the pinout nomenclature of the key switch:

S-Solenoid. As you can see it the circuit goes through the PTO switch and the brake pedal switch before it ends up at the solenoid
R- Rectifier. That is the part that converts AC voltage produced from the stator to DC voltage to operate the electrical components, but to also charge the battery if needed.
M- Magneto. This is the "kill wire". It is nothing more than a grounding circuit to ground out the magneto, and thus eliminating the spark it produces shutting off the engine.
L- Lights. Powers up the headlamps and taillamps when the key switch is in the first clockwise position.
B- Battery. Ends up initially at the ammeter, then to the other pole of the ammeter, then through the 10A slow blow fuse, then to a lug on the starter solenoid where it's mated up with the main positive battery cable.

Switch nomenclature:
N/O- Normally open
N/C- Normally closed

 

[Gary James]

I tried the replacement and the only thing it does is turn on the lights. If you look at the 725 wiring, the connectors are labeled in different places on the 925 (differences above). Apparently the 1872 is wired differently than the others. According to the iSaveTractors.com rep,

"Yes that switch you linked of ours is the correct switch for you. The terminals may not be in the exact spot as your old one so double check before installing and move any wires you need to in your plastic connector to match ours."

Also there is no place designated for the white Run wire on the 925.

 

[lpalma]

This is from the wiring diagram book I have.

 

[mgonitzke]

I tried the replacement and the only thing it does is turn on the lights. If you look at the 725 wiring, the connectors are labeled in different places on the 925 (differences above). Apparently the 1872 is wired differently than the others. According to the iSaveTractors.com rep,

"Yes that switch you linked of ours is the correct switch for you. The terminals may not be in the exact spot as your old one so double check before installing and move any wires you need to in your plastic connector to match ours."

Also there is no place designated for the white Run wire on the 925.

So just to be clear here, you are using an aftermarket switch, not the OEM switch? If so, please post a link to the switch you are actually using.

 

[1811Cub]

Yes that switch you linked of ours is the correct switch for you. The terminals may not be in the exact spot as your old one so double check before installing and move any wires you need to in your plastic connector to match ours."

If you have to move wires in the factory connector, it is NOT the correct switch, PERIOD.

 

[1811Cub]

One glaring difference in the diagrams is the lack of a lighting circuit fuse on the one Lew posted.

 

[mgonitzke]

Is it this one?

That is NOT equivalent to the OEM switch, regardless of what the site says. It is quite disappointing to see such a misleading description from what I had thought was a reputable seller. That switch won't directly replace the OEM switch on ANY Cub Cadet garden tractor, to my knowledge.

Either buy the correct switch, or rearrange the terminals in the connector to match the switch.

 

[1811Cub]

The ISAVETRACTORS replacement switch:

Compare to OEM MTD switch 925-3026:

 

[lpalma]

I have a new oem switch, I notice the back is not marked, but it is oem...

 

[1811Cub]

You have to be careful with those switches. The battery ignition switches and the magneto ignition switches look very similar, and both have 5 blades. I wish they had at least put a partial part number on them to identify them easier.

 

[dschwandt]

Be careful that the key does not come out when in the run position.
I have bought several supposedly OEM switches that the key will, slip right out when in the "run" position.
Test it while you still have it in hand, if it does, send it back.
Damn things are made in India of all places.

 

[MarcHeld]

I had tried to post to this a few weeks ago but for some reason it didn't post.

For 1872 afficionados- I had got my tractor to run a couple of times. I'm sure you have read about gasoline getting into the crankcase. This is the second time for me. Carburetor and fuel pump. I had bought cheapie knock-off carbs. I finally went with iSaveTractors for the carb. As for the fuel pump, that thing has the most cockamamie method to add the attachemnts. A circular clip that is almost impossible to press into the tabs. Even a snap clip tool is iffy. Finally I got a clean install. Had to drain the oil twice until I got a carb that would not overrun into the cranckcase. I finally got both on and ready to run.

Sat down to start my baby up- broken ignition switch. I have a feeling the off and on starting might have been inside the switch. Got one on order.

Gotta keep my baby running!!!!!

Gary,
Everything you mentioned has happened to me on my 1811. It was so eerily similar, I thought that I was the author of the post. My ISaveTractors carb finally solved this problem. Also have a new fuel pump (with cockamamie fittings) several oil changes, new ignition module, a clanky kill wire behind the ignition switch, new battery. With all the issues sorted out she finally earned a dual hydro valve, power angle cylinder for the snow blade. Refreshed mower deck, painting rusty spots, and a front bumper.

 

[Gary James]

I just now saw the posts. Yesterday I got the 925-3026 part. Only the S and G pins were marked but I verified it was correct with a voltmeter. Yes, the pictures describe my situaation exactly. I put it on and at first absolutely nothing. Apparently another connector got loose. Got everything in order and now it turns over. I'm just glad I didn't burn up the magneto. Thanks for the info!!!

 

[Gary James]

This is the most confounding problem I've ever had with this tractor. Starter turns over fine due to the new ignition switch. New carburetor (actually tried two different ones). I have replaced the fuel pump twice after the first one was leaking out of the side that goes to the carb. Took the fuel line off the carb. Spurting fuel.

Spark checker lighting up on both cylinders. Actually took the plugs out and checked them by grounding to the body.

I hate messing with new carb settings but after messing with two carbs not one hit on either cylinder.

Starter was replaced two years ago and runs great.

What is so aggravating is I had gotten the engine to run for about 5 minutes a couple of weeks ago until the new fuel pump was leaking out of the outlet and replaced the pump.

Suggestions?