8N keeps breaking starter drives

   / 8N keeps breaking starter drives #1  

fibrostic

Member
Joined
Feb 17, 2011
Messages
36
So after much advice form this baord my 8n is up and running great. Sounds better than the day I bought it. Takes about half a second to start and runs liek a champ. EXCEPT.... i have gone through 2 starter drives (bendix?) in the past 6 weeks. the first i bought from an internet auction site so i thought maybe my cheapness was my weakness, but now i broke one from TSC. the first was just cracked down the length so i got it all out, but the second one broke off in the bell housing. when i pulled the starter, the gear part of the starter drive just wasnt there. Is this a sign i need to replace the ring gear? Thoughts?
 
   / 8N keeps breaking starter drives #2  
do you know of any starter rebuilders in your area. very slim possibility the ring gear would break the gear especially from your statement about how good it started a couple of times bad ring gear will show itself at most cranking attempts if you cant find a rebuilder let me know where you are located and i will direct you to one. if possible can you post pictures of the broke drives and if you can a picture of the old drive. now to change thoughts does the engine have any back fire problems either at cranking or at shut down this is the most common problem that kills the starter drives and armatues in these units.just repost what you can.
 
   / 8N keeps breaking starter drives #4  
Do you have a hydraulic pump on the front of the engine? It could be causing so much back pressure that its breaking the starter. I have seen it happen before.

Chris
 
   / 8N keeps breaking starter drives #5  
IS this a 12v converted tractor? If so, busting the bendix off the front of the starter is indeed a common problem.

I am sure others will chime in if this is indeed the issue. But I "think" you can get a heavy duty bendix. But I am not sure. They also make 12v starters made for converted tractors.

We had the same problems on dads 8n. Allthough it is only 6v, before the rebuild we had to jump it a lot with 12v direct to the starter. And it broke more than once.

I cant remember what we did to fix, but I think we welded tie gear or washer or something on the end instead of the snapring or clip that it had. But I cant remember for sure. That was too long ago
 
   / 8N keeps breaking starter drives #6  
...only other thing can think of is starter misalignment...
 
   / 8N keeps breaking starter drives #7  
I think LD1 hit it.

it's quite common for 6v starters using 12v to break oem drives.

there are a couple different drive types including follow thru..e tc. if enither work.. my advice is... rebuild the starter for 12v... it will slam less...

soundguy
 
   / 8N keeps breaking starter drives #8  
my saying see a rebuilder did not mean to get your starter rebuilt but as a second opinion about what may be causing the broke gears. there was only 1 common drive for these units the common rebuilder part number was 4-502 accurate manufactured drive. there is a rubber mount version of this same drive that is commonly used for the 12v converted starter the rubber cushion was used to absorb the 12v power for the same unit as was built from the 6v version also many of these tractors were converted to 12v but the 6v starter was left intact and not converted this has worked fine for many years the only drawback to leaving the starter 6v was if you had a cranking problem you will eventually blow the starter up literally. i have sold hundreds of these drives over the years with just as many starters also and as a side not several years ago many of the drives coming from asia were 'JUNK' i had some of them and threw them in scarp and went back to reman o/e drives and finally now only sale the rubber cushion version which if all else works the problem is fixed
 
   / 8N keeps breaking starter drives
  • Thread Starter
#9  
I think part of the issue was that one of the girls who cleans stalls at the farm would hit the starter, and if it didnt crank right up, would hit it again before it stopped spinning. Thus i think the bendix would expand and catch the flywheel whil in motion and bind against it. This is evident as now the flywheel has 2 teeth missing, enough that ocassionally the starter will not be able to catch the flywheel. Rolling it over an inch or so allows it to catch again.
 
   / 8N keeps breaking starter drives #10  
I think part of the issue was that one of the girls who cleans stalls at the farm would hit the starter, and if it didnt crank right up, would hit it again before it stopped spinning. Thus i think the bendix would expand and catch the flywheel whil in motion and bind against it. This is evident as now the flywheel has 2 teeth missing, enough that ocassionally the starter will not be able to catch the flywheel. Rolling it over an inch or so allows it to catch again.

Is it a 12v converted tractor??
 
 
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