Problems starting IH 784

   / Problems starting IH 784 #1  

tarquin2

New member
Joined
Oct 9, 2010
Messages
15
Tractor
international 784
Hi all, not sure if ive put this in the right place but i hope you can help!
Just over a year ago i bought an International 784 (30+ years old - not really vintage i know), it ran fine for a couple of months then the fuel lift pump gave up so it had a new one of those fitted with a non return valve in the supply fuel line just for good measure. Since then it has been really difficult to start by just cranking, the smallest squirt of EZ start has it roaring to life immediately though. The smoke when cranking is white ish but when started virtually dissapears, maybe a slight blue haze. Has anybody got any thoughts as to what the problem could be?
Many thanks for your help
 
   / Problems starting IH 784 #2  
every 784 i have ever seen or owned needed alittle staring fluid to start they came with a ether kit on them so it wont hurt to use a little if using it right
 
   / Problems starting IH 784 #3  
Engine cranking speed is very critical and with a worn engine they get harder yet to start!

We had even used a Jd starter off the 4430 I believe and that worked the best although it could not be used with most loader frames do to it's larger diameter and loader frame location.

We found this was better then trying to oversize the batteries to get the cranking speed. I don't know what your engine is in it's life cycle but I'd go to a 2500 watt block heater before I'd be using fluid to start it all the time.

Depending on hours and work that has been done on the engine DO NOT use after market head gaskets on this engine unless they are the steel shim!!!!
 
   / Problems starting IH 784
  • Thread Starter
#4  
Cheers, I will have to try and get hold of another starter motor to try it. Might have to be a straight swap since the loader frame gives it very little clearance. I hadnt thought of changing it before since it sounds ok when cranking, I was thinking more along the lines of fuel starvation or low compression. But not being a mechanic I am clutching at straws really. I will let you know how I get on, the only trouble being is I dont want to throw good money at an old machine that is potentially only going to get worse, but at the same time We can only afford to buy an old tractor
 
   / Problems starting IH 784 #5  
Sounds to me as though the injection pump timing is out a few degrees or the compression is low. If pump timing is out nothing you do with the starter will make any difference.I would start by checking that the pump is timed correctly and doing a compession test
 
   / Problems starting IH 784
  • Thread Starter
#6  
How do I do a compression test? Please excuse my ignorance but as I am not a diesel mechanic I dont have a clue as how to do it, but Im trying to learn fast.
Timing can be checked by removing a cover on the pump and checking that some marks line up, what would cause this to alter?
Thanks for your help
 
   / Problems starting IH 784 #7  
you would need to find a diesel compression tester,probably best to get a mechanic to do this as these testers are expensive so most companys won't lend them.Usually means removing the injectors and screwing in a adapter in the injector holes and cranking the engine.Before you do this check the stop lever is adjusted correctly and that it linkage travels the full length as it may not be opening the pump completely.
Check that all the timing marks line up as with wear they can move slightly.
It would seem strange that this has only started since changing the lift pump and fitting a non return valve.Was the injection pump removed at this time?
White smoke indicates that it is getting fuel but engine is too cold to ignite it or that the fuel is getting injected at the wrong part of the engines stroke ,which is why i mentioned checking the timing so if the timing is ok maybe look at fitting a block heater and this problem should dissappear as engine would always be warm.EZ start is the best way to stuff a engine and should only be used as a last resort.
 
   / Problems starting IH 784
  • Thread Starter
#8  
No the injector pump remained in position next to the block. The lift pump on the "deluxe" model is situated under the cab below where the drivers right foot would be. Standard models are gravity fed to the injector pump, because this model has an all singing and dancing cab (in its day) it is fitted with belly tanks and a pipe connecting them both.
Fitting a block heater would not work with my currrent set up, since it is normally parked at least half a mile from any source of electricity and at least five miles away from my house. The joys of being a peasant farmer!
 
   / Problems starting IH 784 #9  
I'd either say the timing is slightly out, or it isn't cranking fast enough.

First of all, check your battery, and if it is holding a good charge and not too old, try replacing the starter motor.

Let us know what happens! :)
 
   / Problems starting IH 784
  • Thread Starter
#10  
Replaced the battery last winter because it was pretty old, not the original but still about 18 years old.
Checked the timing, looked pretty good to me, although I am not a perfectionist I try my hardest.
Didnt get someone to test the compression because those who where able enough to do it in the next month were too expensive , and the ones who were able to do one on my budget couldnt do it quick enough for my liking.
So I bit the bullet and bought a new starter motor. When I crank it over it sounds like it will take off, and it would probally power the whole tractor just by keeping the key turned, PTO included.
It might not be the ideal solution but it has got the old girl up and working for just a little bit longer.
Thanks for everyones help and ideas
 
 
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