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lx178 overheating

#1

G

gunsaul

my john deere lx178 coolant light is coming on after a little while...sometimes causes the mower to bog down...radiator is full...screens are clean..help!


#2

M

motoman

gunsaul, What is a "little while"? More information needed so the pros can answer you.


#3

G

Gunner13

Hi Gunsaul, Over the last month, the overheat light on my LX178 was intermittently illuminating and the engine would occasionally die or sputter when the light flickered on. A week ago, the mower stopped running. The stop was very sudden as if the ignition had been turned off. I looked over the engine and found a loose wire on the front-left side of the engine which seemed to lead to a brass doohickey (sorry if I'm getting too technical;) protruding from the engine. Doing a little internet research, I learned that this brass widget is the engine coolant temperature switch. It is an electric switch that is designed to turn off the engine if it gets too hot. When mine broke off, the engine died.

I purchased a new switch from my local John Deere dealer. The JD description is simply "switch" and the JD part number is M96786. My cost was ~$36 + tax. It's easy to find on the internet. I found other part numbers for this switch in various Kawasaki FD440V V-Twin engine parts lists: F-27010A and 27010-2181, but the John Deere parts guy said he didn't know what those number were.

The old switch was physically broken - the plastic portion that supports the electrical terminal had broken out of the brass threaded housing. I used a 21mm socket to unscrew the old switch. The coolant comes out of the engine when the switch is removed, so I quickly installed the new one. When I examined the old switch, I noticed it has a washer designed to fit between the switch and the engine. The new switch did not include a washer, so I decided to salvage the old one. The washer was well stuck, but a little gentle encouragement with a small screwdriver freed it up. I very briefly removed the new unit long enough to get the washer on and then re-installed it. It's a good idea to have a catch-pan under the engine, but you shouldn't lose more than a couple of ounces of coolant. The switch has a single electrical post on it that sticks straight up, so a deep 21mm socket is preferred. I didn't have one, but my standard socket was long enough to grab the top 1/3 of the brass hex head and allowed me to complete the installation. The electrical terminal from the old switch had broken off in the lead wire, so I simply removed the broken terminal and pressed the lead wire onto the new switch. The mower fired right up.

I mixed up some new coolant to replace the small amount that had leaked, refilled the coolant tank and I am back in business.

I'm not sure if this is the same problem that you have, but it sounded similar. Hope it helps.


#4

BBO

BBO

my john deere lx178 coolant light is coming on after a little while...sometimes causes the mower to bog down...radiator is full...screens are clean..help!

I would suspect the thermostat or the water pump.


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