4230 starting problems

dragonsbane1964 · Aug 12, 2015

I have a question for someone. I have a 4230 that I bought and rebuilt the motor. Did an in-frame in it. New liners, pistons, bearings, and had injection pump rebuilt by a reputable place. Crank shaft and Camshaft timing marks line up. Injection pump marks line up also. Checked cam gear and Crank gear to make sure the keyway had not slipped. Both still in good shape. Tractor will turn over and smoke some out of the exhaust but will not fire off and run. Has more smoke then it did when I first got it but not like it should. Valves are adjusted to what the book I have says. .018 intake and .028 exhaust. It seems like the #1 injector is opening when the intake valve is open or close to closing. hard to tell. From everything I see it should fire up and at least run some. Any ideas on where or what to look for ? Any ideas would be appreciated. Thanks

jd110 · Aug 12, 2015

The injector should fire when piston is a tdc and both valves are closed. I am wondering if the injection pump is 180* out of time.
On the right side of the block near the flywheel, you should find a couple of plastic plugs. A large one maybe 1 1/4" and a smaller one under it. If you remove the small one and stick a 3/8" bolt maybe 3" long in it. Then turn the engine over by hand in normal direction of travel while pushing in on the bolt. When the bolt drops in a hole in the flywheel, it is at tdc. To determine whether it is tdc compression or exhaust, you need to check the valves. If the intake and exhaust rockers are both loose on #1, it is on compression. If rockers are loose on #6, you are on exhaust stroke and need to turn engine over 1 revolution to get on compression. While bolt is engaged in flywheel on #1 compression, the timing marks need to be aligned in timing window on side of injection pump. If all this is in alignment, the engine should start. Did you have a valve job done on the head? Sometimes 4230's can be hard to start if valves are worn and sunk too far in the head. It makes compression too low.

dragonsbane1964 · Aug 12, 2015

Tdc is at #1. Both intake and exhaust are closed. I've had head redone. Valves, etc by a local shop who came rrecommended. I sent injection pump back to have them recheck it. Was thinking the same thing. May be 180 out. Only other thing I could think of was cam may have twisted but have never heard of that. Break yes, but not twisted. Cam and crank both looked good to nakid eye. Thank you for your reply. This thing is driveing me crazy.