Bobcat 743 won't start

[Writer2783]

I have a question on my bobcat 743, it's an 83. Wondering if anyone has had this problem or may know what's going on. It has the Kubota 1903v diesel engine. I think it has been replaced. Rebuilt the head on it. New fuel pump and battery. Tried to start it and with the battery on a full charge it cranks and puffs white smoke. It sounds like it is about to start then doesn't, the starter is new also. Tried to start it with ether and it still does not start. The solenoid reads 6 volts and I know it should read 12v. The glow plugs have not been replaced and could be bad. But shouldn't the ether make it fire anyway? Also the weather has been warm out. Someone said it might be that the timing is off. Anyone ever had this happen or might know what going on? Should it start with ether regardless of the solenoid and/ or glow plugs? Thanks!

 

[Fishfiles]

how bout a little more info , did you just rebuild the head and this just started , or did it quite running then you rebuilt the head , who adjusted the valves ----------how and when did it quite running , did it sputter and kill , did it just not start one time , a lot of possibilities from the info you gave

 

[Bobcatdan]

how bout a little more info , did you just rebuild the head and this just started , or did it quite running then you rebuilt the head , who adjusted the valves ----------how and when did it quite running , did it sputter and kill , did it just not start one time , a lot of possibilities from the info you gave

There is not much that a person can screw up R and R ing a head. I don't know, put the head gasket on wrong? When you took the injector lines of, did the barrles on the pump move, that can mess up pump timing. Does it turn over like it has compression?

 

[Tazza]

There is not much that a person can screw up R and R ing a head. I don't know, put the head gasket on wrong? When you took the injector lines of, did the barrles on the pump move, that can mess up pump timing. Does it turn over like it has compression?

I have to agree, hard to mess up a head replacement. There is no reason for the timing to be out, the cam shaft is lower and does not get touched. The valve clearance must be right or the compression will be low and it will jsut puff smoke.
That is a replacement engine, the original is a V1702.
Remove the plugs and test them. Use a jumper cable and hold to the body of the plug, connect the cable to one terminal then the threaded base to the other terminal. The plug should glow to the tip.
Ether should have made it pop, but if the clearance is wrong, it will not fire.
From memory, the clearance should be close to .008

 

[Fishfiles]

I have to agree, hard to mess up a head replacement. There is no reason for the timing to be out, the cam shaft is lower and does not get touched. The valve clearance must be right or the compression will be low and it will jsut puff smoke.
That is a replacement engine, the original is a V1702.
Remove the plugs and test them. Use a jumper cable and hold to the body of the plug, connect the cable to one terminal then the threaded base to the other terminal. The plug should glow to the tip.
Ether should have made it pop, but if the clearance is wrong, it will not fire.
From memory, the clearance should be close to .008

if he adjusted the valves right down the line without getting the tension off the valves before adjusting , then it won't run and it will puff smoke while trying to start as the valves that were adjusted without getting the load off them will not shut and no compression will occur on those cylinders and the unburned will show up as smoke , another common mistake is to leave out the minuture hockey puck looking cap which goes on top of the valve stem -------- so I would think it is pretty easy to screw up a head replacement job if you don't know what your doing or think that you do but don't ------------------

 

[Tazza]

if he adjusted the valves right down the line without getting the tension off the valves before adjusting , then it won't run and it will puff smoke while trying to start as the valves that were adjusted without getting the load off them will not shut and no compression will occur on those cylinders and the unburned will show up as smoke , another common mistake is to leave out the minuture hockey puck looking cap which goes on top of the valve stem -------- so I would think it is pretty easy to screw up a head replacement job if you don't know what your doing or think that you do but don't ------------------

Fishfiles - so very true, even different locations of the push rods will mess with the valve clearance. Hopefully this is all that is wrong.