Tractor Will Not Start

[Dave M7040]

Each glow plug will read low ohms, like 10 or less.
Be sure to disconnect each one from the buss bar that joins them and read from connection to ground.
Also if you cycle the plugs each one should feel warm to touch for a very basic go/no go test.

I am wondering if the GP resistance value is a lot closer to 1 ohm.

Are you following the fuel system bleeding steps in the Owner's Manual?

Not bleeding properly is a major reason for a no start condition.

Is the glow indicator on the dash appear to be working properly?

Do you have the free workshop manual available here?

Download Cub Cadet 7 Service Manual | ManualsLib

You can also find an Owners' Manual on the same site.

All engine timing marks are on the front of the engine none on the flywheel.

Dave M7040

 

[bill18163]

I think I did read somewhere where the resistance should be one ohm or a small bit more on the GP's. Yes we did bleed according to the sequence in the manual. Interesting that you mention the glow indicator on the dash. My neighbor showed me how it comes on but goes out very quickly. There is some kind of timer module below the dash I think. I wonder what the specs are on that. Like how long should it stay on. The garage is warm when we are working but not hot. Maybe 65 degrees. But when I watched it when he turned the key it stayed on about five seconds and went out. I'll try to convince him to pull those GP's and test them before he starts tearing the engine apart. He is getting very upset and worked up over this and he has to go to work every day. I'm retired so I have more time than he does to do research on this problem. Thanks Dave M7040 for the info on the timing marks. It bothered me that there are no timing marks on the flywheel. You put my mind at ease on that issue.

 

[Dave M7040]

I think I did read somewhere where the resistance should be one ohm or a small bit more on the GP's. Yes we did bleed according to the sequence in the manual. Interesting that you mention the glow indicator on the dash. My neighbor showed me how it comes on but goes out very quickly. There is some kind of timer module below the dash I think. I wonder what the specs are on that. Like how long should it stay on. The garage is warm when we are working but not hot. Maybe 65 degrees. But when I watched it when he turned the key it stayed on about five seconds and went out. I'll try to convince him to pull those GP's and test them before he starts tearing the engine apart. He is getting very upset and worked up over this and he has to go to work every day. I'm retired so I have more time than he does to do research on this problem. Thanks Dave M7040 for the info on the timing marks. It bothered me that there are no timing marks on the flywheel. You put my mind at ease on that issue.

I quickly looked at the Cub Cadet 7600 series wiring diagram re the GP indicator. Is there any chance this is a glowing coil of wire and not a light bulb?

Typically the GP's are designed for 10.5 volts. DO NOT go testing them in open air. They could blow up in your face as they rely on the heavy metal of the head to moderate their temp rise. If you must, clamp them in a heavy vice as a heat sink.

Again typically, the key switch in the pre heat position sends power to the GP's through the glow indicator which is actually a resistor in series with the GP's and lowers the voltage down from a nominal 12 volts. When the key switch is turned to START, the glow indicator is bypassed and power flows to the GP's while the engine is cranking. The reason for the bypass is that the starter is drawing down the battery voltage.

I am not saying there is no timer module just that I do not see it in the wiring diagram I found.

Another thing to try is to blow warm air from a heat gun or hair dryer into the intake after the filter.

Dave M7040

 

[dodge man]

If it had good compression and it’s getting fuel it seems to me 65 is warm enough to start without glow plugs.

 

[PILOON]

I am wondering if the GP resistance value is a lot closer to 1 ohm.


Dave M7040

Always possible as there are some that are 'fast glow', so to speak.
But to get heat resistance is needed and a 'near short' will do that.
So fast glow would need to be hot and fast ergo low resistance.

Fastest, easiest is finger contact on each plug after a cycle (on cold engine). Not scientifically accurate but good enough.

 

[3gunr]

I have the same tractor with the same issue. If i press the throttle pedal to the floor it will start . i have also when it was very cold , gave a tiny shot off starting fluid and it starts right up.

 

[George2615]

I think I did read somewhere where the resistance should be one ohm or a small bit more on the GP's. Yes we did bleed according to the sequence in the manual. Interesting that you mention the glow indicator on the dash. My neighbor showed me how it comes on but goes out very quickly. There is some kind of timer module below the dash I think. I wonder what the specs are on that. Like how long should it stay on. The garage is warm when we are working but not hot. Maybe 65 degrees. But when I watched it when he turned the key it stayed on about five seconds and went out. I'll try to convince him to pull those GP's and test them before he starts tearing the engine apart. He is getting very upset and worked up over this and he has to go to work every day. I'm retired so I have more time than he does to do research on this problem. Thanks Dave M7040 for the info on the timing marks. It bothered me that there are no timing marks on the flywheel. You put my mind at ease on that issue.

I agree to test each glow plug resistance first then check if voltage is getting to them when the GP light is on. That Cub has the same Mitsubishi engine that was in my 2004 Mahindra 2615. I replaced 3 sets of plugs over the years before I found there was an upgrade kit. The kit included new plugs (different than orig) and a new timer (longer cycle time). No starting problems after installing the kit. The original plugs had a habit of either shorting out or going open and the timer cycle time was too short. The kit addressed those problems.

 

[PILOON]

On one diesel vehicle the timer was very $$.

I simply installed a momentary push button and counted thousand and one, two etc., worked like that for 3-4 years.
If no success on first count I'd do another adding more seconds.

Knew on guy that simply pinched a pair of wires under his dash!

 

[bill18163]

George2615,
Do you have the information on that upgrade kit?

 

[George2615]

George2615,
Do you have the information on that upgrade kit?

No I don't. Its been 8 years since I got it and I've since sold that tractor. All Mahindra dealers were notified of the upgrade but everytime I went to get new plugs the dealer never mentioned the upgrade. I think he thought if he sold me the upgrade kit I'd stop coming back every couple years and spend over $100 for new plugs. I actually found out about the upgrade from a dealer in Batavia, NY who is/was a member here and bought it from him.
There is a thread on this is the Mahindra section. Found a couple links.

https://www.tractorbynet.com/forums...ng/389990-yet-another-mahindra-glow-plug.html
https://www.tractorbynet.com/forums.../369889-2015hst-mahindra-glow-plug-issue.html
https://www.tractorbynet.com/forums...ting/389741-mahindra-2615-gear-glow-plug.html
This link has the members name who I bought from. Sorry, but I don't know if he's still in business. (LawallsTractor)
https://www.tractorbynet.com/forums...5095-installing-glow-plug-conversion-kit.html