International Harvester Model LB Engine Question

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papermaker

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I recently bought International Harvester Model LB engine. While moving it the flywheel got moved and the valves wer stuck. The intake rocker arm stapped at the end nearthe push rod. I think ive found a source of a reproduction but I haven't given up on looking for an original.
The question I have is Im not getting spark from the magneto . I took the cap off and used the tester on the end of of my index finger to check for spark by touching the brass nub on top of the coil. Yes I'm Crazy!
The points look clean but I did run a point file across them. I'm assuming now that the coil may be bad. Is there a way to test the coil to see if that is bad.
This engine was on a old cement mixer and there is a hole about the size of a quarter it the top of the water hopper. Any thoughts how to repair this?
 
papermaker said:
I recently bought International Harvester Model LB engine. While moving it the flywheel got moved and the valves wer stuck. The intake rocker arm stapped at the end nearthe push rod. I think ive found a source of a reproduction but I haven't given up on looking for an original.
The question I have is Im not getting spark from the magneto . I took the cap off and used the tester on the end of of my index finger to check for spark by touching the brass nub on top of the coil. Yes I'm Crazy!
The points look clean but I did run a point file across them. I'm assuming now that the coil may be bad. Is there a way to test the coil to see if that is bad.
This engine was on a old cement mixer and there is a hole about the size of a quarter it the top of the water hopper. Any thoughts how to repair this?
Click to expand...

I think my Dad would use a timing light to check voltage and timing. I was a kid at the time, sorry. Good luck
 
papermaker said:
I recently bought International Harvester Model LB engine. While moving it the flywheel got moved and the valves wer stuck. The intake rocker arm stapped at the end nearthe push rod. I think ive found a source of a reproduction but I haven't given up on looking for an original.
The question I have is Im not getting spark from the magneto . I took the cap off and used the tester on the end of of my index finger to check for spark by touching the brass nub on top of the coil. Yes I'm Crazy!
The points look clean but I did run a point file across them. I'm assuming now that the coil may be bad. Is there a way to test the coil to see if that is bad.
This engine was on a old cement mixer and there is a hole about the size of a quarter it the top of the water hopper. Any thoughts how to repair this?
Click to expand...

A magneto won't produce any voltage unless the engine is turning over. There are businesses that rebuild magnetos for old tractors. One of them might be able to help you if yours is bad.

Here's a manual:
http://staverloekk.no/jostein/motor/Dokument/International HC LB Man_parts.pdf
 
Im not an expert on Mags but there are a couple of things you could check. Does the spring mechanism wind up and release when you roll it over, you should hear a bang as it releases, if not make sure your turning it over in the right direction, they only work one way. Without that wind up mechanism you won't get much spark turning it over slow. Do the magnets seam strong, I've had them where they weren't and you'd only get the faintest of spark. The finger test should have worked though. Check that the grounding lug for shutting it down isn't shorted. Some, Im not sure if they all but i expect so used some sort of dry capacitor or condenser in them to keep the points from burning, make sure it isn't shorting. Good luck, they contain a certain amount of black magic and the voodoos who can fix that sure know how to charge. Pun intended.
Oh if all else fails you can use the points with an external condenser to trigger a coil connected to a 12 volt battery. I've seen that done many times
Good luck
Greg
 
Have you checked the old engine forum www.smokestak.com ? They have a classified section and a lot of helpful members with like engines. As to the mag, clean all contact surfaces and points; try a new or substitute condensor. Can not recall whether mag is impulse or not. If you turn it slowly and hear a snap at one location, it is impulse mag; if no snap, mag does not have impulse and depends on cranking at a slightly faster speed.

Is your engine the 3 to 5 hp or the smaller size?
 
Well as long as you have points that will make and break no reason why a cond. and reg coil wont work also a Model T coil. As far as the
hole? If its not suppose to be there maybe plug it with a brass plug. need picture of that...??

I am just saying a coil just to get it started, then bench test the mag turning it with a drill or something.
 
The coil is fairly easy to check and there is a wealth of info on Google to check everthing . But basicaly you can check the coil with a digital multimeter , the primary side of the coil should indicate about 6-700 OHMS. and the secondary side of the coil will show about 7000O OHMS .Now these are not absolute values and your coil may show a bit higher or a bit lower . Also you could have a problem with filing the points .Experince has shown me that stoning the points flat and then cleaning with Acetone or other cleaner which will dry without residue. Most times a mag will come to life with a good cleaning and light oiling Also the point gap is .016 If the points are not burned then probaly the condenser is good ,you will find info on Google on how to determine if the condenser is Ok. Hope this helps
 
check out Shopdogsam on youtube.he goes into depth on rebuilding mag and you can
see it being done.
 
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