I have a 1989 743 with the kobota diesel in it.ive owned for many years so I know its quirks.it sat untouched for a full year.it allways started with around 60 seconds of glow.never needed quick start.i now have to use quick start.the glow plugs are getting power and if I don't glow it and just try quick start it wont fire which would seem to say they are working.i had them out 2 years ago and they were in perfect working order.ive put fuel additives in the fuel,used at least 3 tanks of fuel since it sat,it runs perfect and starts perfect when hot.im told my injectors need to be replaced,but I thought I will ask the real experts
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bobbie-g
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Do you know what the compression is? Will it not start at all without starting fluid? 
--- Bobbie-G
--- Bobbie-Gno it will not start without quick start.but before it sat It never needed start fluid.once its running it has lots of power,i have used it hard since I got her back,i read to put injector cleaner in the fuel filter and I will try this with a new filter.ive owned this machine for many years so once its running its as good as it ever wasDo you know what the compression is? Will it not start at all without starting fluid?
60 seconds is a fairly long glow, i'd start by pulling the glow plugs and checking that they are in good shape still. I had a 743 that took long glows like that, it was well worn, but the plugs didn't glow very well, i replaced them and it started a lot better.
Start with pulling the plugs and testing each one with a wire and battery, they should glow red right to the tip.
thanks tazza,i did pull them 2 years ago and bench tested them,every one took 14 seconds to completely glow red,so I put them back,it seems it is a problem from sitting,becaure prior to the year it sat it allways started,and in the summer it would start after 30 seconds,i will pull the plugs and replace,put cleaner and fuel in fuel filter and go from there.i know in life u get what u pay for,but are there any decent china injectors,the oem are real pricy up here in Canada,with exchange and shipping added on.there is sets on ebay and amazon .I don't use this machine very often anymore so I don't want to spend the bank on her.she needs a rad and muffler too,so im hoping to fix the starting problem without too much cost
When its running, does it blow an smoke? if it's clean burning, your injectors should be fine, no need to replace them.
No need to replace the glow plugs if they bench test well again, just throw them back in.
The next step is to check how much blow by you have, the tube that hangs down the side of the motor, put your finger over it lightly as it's running, see how fast pressure builds up. It's normal for a little to build up, but when there is a lot and smoke coming from it, you have a fair bit of wear, the only way to cure it is to swap or reuild the motor.
I will try that.ive ordered new glow plugs,17 bucks a piece for ngk,s no shipping,its just strange that after it sat it wont stert,when before that it started everytime.theres some black smoke at startup but nothing to speak of when running.
Black smoke is good smoke, white smoke is no good for multiple reasons. Plus if smoke clears up after starting is a good sign too. mine would need a half a can of juice to start up...white smoke everywhere...and continued to smoke white while running
I had a machine that used to make clouds when cranking, white smoke everywhere. When running it was good as, started easily when warm.
As the smoke clears up after starting, i feel it's ok too. If it was a dirty injector i'd think it would blow smoke all the time.
so is I got some time to work on the 743 today.i changed the fuel filter,flushed the hydro system,cleaned and greased.i have found that the primer bulb goes soft after about 15 minutes.again once started and warm it starts as good as new.does this mean the lift pump is letting pressure bach to the tank.i see no leaks in fuel system accept a small bit of seepage into the unit the pump goes to.it has allways been like that.i checked the breather tube,some blow by but not horrible for a machine of her age.no smoke of any kind when running,just normal exhaust,any help on the fuel pressre would be appreciated
I thought the pressure was only about 3-5psi, not sure i'd blame the lift pump on the soft hand primer, i thought the primer was before the lift pump anyway, for it to be sucked flat or sucked in at all, it would be due to a restriction between it and the fuel tank. It should only be firm when you're priming the system.
so after a total maintance go over,i figured it out,it was the lift pump,it had a small leak and when I pumped the primer bulb it made it show,new pump and she has never started like this.20 seconds of glow on the new glow plugs she fires right up,no quickstart,and very little glow,im happy,and thanks to all who chimed in
Awesome, glad it was an easy one, even better that you don't need any starting juice now.
