Update. I found that the ignition module in the distributor wasn't working right. It kept the timing advanced when the engine was cranking. Changed the module and it starts with just a touch of the key. Now I have to replace the starter since the bendix shaft is bent and causes it to stick in the starter housing. Guess a backfire will do that...............

Thanks for the replies guys!

Well, I went back and set up the timing and it's much better now. No more kickback when cranking but if it doesn't start on the first try, the motor will spin over backwards a couple of revolutions when I release the key from the start position. Then it's cranking time again until the fumes clear out of the air filter. After that it starts really easily.

I remember adding the MCFA delay timer to many Cats years ago when they first came out. Nothing like having to change an engine just because the ear for the starter mounting hole is broken off the block.

I've found that Hyster, Cat and Clark all had the same problem, yet the local Toyota dealer says they've never had the problem. Wonder if they all came up with the same fix because the price of their kits varies from $170 to $450cdn.

the "kickback" is the reason why MCFA added a 1/2 second spark delay to the 4.3 GM equipped models, as the delay, (if correctly installed) allows the starter to engage before any spark is introduced. This is more a function of how much compression these engines hold than anything else, and the result of the kickback is usually a broken nose cone on the starter, or a broken block where the outside starter bolt mounts to. In CARB (emmission controlled by computer) trucks, the crankshaft sensor sees 1 complete revolution before allowing spark.

It runs really well once it's started. No, I haven't done any vacuum checks. Vacuum lock off, never dual fuel, it has a dedicated LPG carb.

I can't see what a lack of vacuum would do other than making it hard to start. I've got it starting fairly easily now except for the kickback as the starter is turning the engine over. I even checked the firing order and made sure there weren't any crossed high tension leads.

:intriguing: does this unit run well when it does start? have you done any vacuum checks? does this unit have an electric or a vacuum lock off? was it ever dual fuel?

Hi Guys, I did do the extra ground cable from the battery negative to a bolt on the head but that didn't seem to help.

I'll have to see if I can find another distributor somewhere, but now that I think of it, I previously ran into an instance where there was water in the distributor cap on the same machine. It was pouring rain when I was working on it and didn't think to check the cap. I'll do that tomorrow morning.

I know we have that problem on afew older 4.3's distributer wears unevenly and has to be replaced, if that does.t work try another distributer

this is a common problem with a very simple fix. add an extra ground cable between the battery and engine. the alternator bracket is a good place for it. before you dismiss this as being crazy try it. there was even a tech service bulletin on this problem.