Ford 640 sluggish starting

[Chip in Oldhams]

I have a Ford 640 with a gas engine which, until recently, jumped to life the instant I turned the key, in hot or cold weather. Now it starts very sluggishly once it has set for a while. The starter turns fine, but it takes a while for something to happen, and when it does, it's like it's starting a cylinder at a time with some smoke coming out of the exhaust stack. Eventually, it will get up to speed and runs OK thereafter. Starts fine when hot.
So far, I have cleaned out the sediment bowl, and replaced the points, condenser, and rotor (points set to about .025), but the problem persists. Any suggestions would be welcome

 

[souNdguy]

plugs? plug wires? compression test?


soundguy

 

[old]

Hows the spark look?? You need a good spark that will jump a 1/4 inch gap at ALL plug wires. Also when was the last time you replaced the plugs?? A new set of auto lite 437s may be all it needs. Or when was the last time you checked the oil bath air filter and cleaned and changed the oil in it??

 

[Chip in Oldhams]

Thank you for the replies. This afternoon I cleaned and changed the oil in the air filter bath. I currently have AL 437 plugs in it, which were installed about 2 years ago, along with new plug wires. Perhaps they don't last that long. I will check the quality of the spark as suggested and indicate what I found in the next couple of days. Thanks again.

 

[NoNewParts]

(quoted from post at 15:27:07 03/28/12) I have a Ford 640 with a gas engine which, until recently, jumped to life the instant I turned the key, in hot or cold weather. Now it starts very sluggishly once it has set for a while. The starter turns fine, but it takes a while for something to happen, and when it does, it's like it's starting a cylinder at a time with some smoke coming out of the exhaust stack. Eventually, it will get up to speed and runs OK thereafter. Starts fine when hot.
So far, I have cleaned out the sediment bowl, and replaced the points, condenser, and rotor (points set to about .025), but the problem persists. Any suggestions would be welcome

pull the air cleaner hose off the carb and look at the choke plate.
see the little bypass door in the plate.
is the cross spring on the bypass still there?
they fall off sometimes and make it hard to start cold
if it's there, and working...

you probably have a weak spark.
1 or 2 cylinders are fouling and it's running on the other 2
until it clears up.
happens up here sometimes at zero degrees, even with a good spark.

 

[sotxbill]

my money is on the carb being half stopped up due the the really really bad gasolene.

 

[Chip in Oldhams]

I finally got a chance to get back to the tractor. I checked each of the sparkplugs, and it appears to me that there is a good strong spark from each. I will check the choke plate as suggested, as I am now thinking this may have something to do with the carburetor, which incidentally, is a Marvel Schembler. Is it likely that would have been the original? I agree today's gas is terrible, but I do use Stabil every time I put gas in it. Again, thank you for the replies.

 

[Larry NCKS]

Marvel Shebler (not Shembler) was the original carb. That does not mean it has never been overhauled.