Jinma 284 won't start

[SPIKER]

Connection between the two small poles is about 17.8. No reading from either between pole and case of relay. Does it matter which one goes to the key switch and which goes to ground in this case?

Thanks,

Darwin

PS I took a wire wheel to all battery and ground connections, polished them to a shine, sprayed all w WD40 and re-assembled. No difference. Put the darn mag heater on for a few minutes and it turns over perfectly.

measure resistance between the two posts post one to post 2 then switch, if the resistance is the same then the unit should not be polarity sensitive. some relays have built in diodes and will only work in one way. the main battery hot to the relay and then the relay power wire out to the starter and to the starter sol. is one option

other option is to put hot wire from battery with a 10 ga wire from starter post + to the relay big post, then 10 ga wire from the relay other big post to the tractor starter sol start sol. (where the KEY start wire is going now.) remove that wire and install it onto the NEW relay small coil post where you measured 17ohms. install a 2nd wire from the battery _ cable end to the new relay coil other side. this should make sure you are applying 100% full voltage to the starter coil and starter hot with the new relay.

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