MF250 Perkins hard to start at 40 or below

[TennFire]

I am "messing" with a MF250 that has a cold weather starting issue. This one has the Perkins 3.152 diesel. It has a thermostart which has been recently replaced and tested to confirm it is heating (non contact thermometer). Still, when its 40 or below it is hard to start. I have not tested the fuel reservor to see if its clogged but I did not that it seeped diesel from the reservoir when I changed the thermostart.

Another thing I have noticed is that there is no noticeable place on the ignition switch for the thermostart. I can put a test light on the thermostart and know its working when the key is between "run" and "start". It seems to be spring loaded just past the "run" point and just prior to the starter engagement so I assume that is the sweet spot. However, if I hold the key in that location for 30 seconds or longer, the starter will not engage (not even a click) unless I let the tractor sit for a few minutes.

Suggestions?

 

[Ford850]

Have you tested your battery to see if it's holding a full charge? Cooler weather can slow the crank just enough to make it difficult to start if the battery is borderline.

 

[TennFire]

I used the tractor last week in the mid-50s with no problems. I went to start it Saturday morning (below 40) and had the starting problem. I think the battery is fine since it cranks well - just goes dead briefly (almost like an overheated relay) when attempting the thermostart. As indicated, if I let it sit for just a few minutes, it will crank.

 

[thepumpguysc]

If you think its the thermostart, pull the rubber boot off the intake manifold and get a helper to energize it and crank..
It should look like a flame thrower inside the intake manifold.
What about a lighter engine oil seeing its so cold?? if your using 15-40, maybe go to 10-30.
I would try to advance the pump timing slightly next.

 

[massey driver]

Up here in the North we have engine block heaters installed on our tractors and vehicles. There's many different styles of them. some go into the frost/freeze expansion plugs, also have circulation heaters they can be mounted in heater hose or just a hose from the water pump to the heater then to the engine block. Not sure how cold you get but your best would be to have some sort of engine heater,especially on a diesel.