9N crankshaft pulley loose

jural

Member
I just purchased my first Ford tractor. Currently I use a David Brown. While working on the 9n this weekend I noticed that the crankshaft pulley will sometimes not spin while trying to start it. The bolt is spinning though. Couple of questions. What is the size of the bolt holding the pulley on? Any ideas as to why this is happening? Thanks for all of the help on this. I appreciate it.

Rob
 
Offhand,I'd say that the woodruff key is missing or
sheared,and the bolt holding the pulley is loose.
lha
 
I hope that everything will be common sizes. Do you know the size of the bolt? I tried getting my impact socket through the hole with no luck. Also, any advice on removing the pulley? Again, thanks for the help.
 
(quoted from post at 10:58:16 10/13/14) I hope that everything will be common sizes. Do you know the size of the bolt? I tried getting my impact socket through the hole with no luck. Also, any advice on removing the pulley? Again, thanks for the help.

Assuming an OEM pulley two possibilities come to mind:

1) The sheave is loose on the hub of the pulley
2) The hub on the pulley is loose on the nose of the crankshaft.

The sheet metal sheave is crimped to the solid steel hub. Look carefully to see if the snout on the hub is spinning inside the sheave. You might also try loosening the belt and testing the fit by hand. If loose replace the pulley.

The pulley is keyed to the nose of the crankshaft but the key only goes about 1/4" deep into the hub on the pulley. If the nut comes loose and the pulley gets pulled out that much you lose engagement with the key. If the nut is loose turn the pulley to align with the key. tap it back into place, and tighten the nut. If it has run loose like that for any length of time there is a strong possibility the nose of the crankshaft has worn undersize and you will need to make a more significant repair.

TOH
 
It should be a woodruff key that holds the crank gear on and
extends into the pulley. It is a ¼ by 1 ½ woodruff key part #
74156S according to my book. If the pulley is bad I think you can
just pull it out and get a new pulley. If the key is bad you have
bigger problems as I think you will have to pull the crank gear to
get at the key.
I have only rebuilt 2 engines but I don't think you can get the gear
off to replace the key without at least dropping the pan. If the gear
has sheared the key it will throw off the timing. Maybe someone
else will confirm that.
Like I said I have only done 2 engines and by no means am I an Expert.
 
The tractor will start and run well. That being the case, I "assume" that the timing is good. I may have missed it, but I have not seen anyone say what size the bolt actually is and a good way to get at it. Wrench or socket? I can already rule out impact sockets. The bolt looks to be over an inch. I hope that it only needs to be tightened, but the odds are not stacked in my favor. Chances are that it has been ran like this for a long time. This is my first American tractor. I enjoy my DB, but it is a bear to get parts for.
 
(quoted from post at 11:49:58 10/13/14) The tractor will start and run well. That being the case, I "assume" that the timing is good. I may have missed it, but I have not seen anyone say what size the bolt actually is and a good way to get at it. Wrench or socket? I can already rule out impact sockets. The bolt looks to be over an inch. I hope that it only needs to be tightened, but the odds are not stacked in my favor. Chances are that it has been ran like this for a long time. This is my first American tractor. I enjoy my DB, but it is a bear to get parts for.

The OEM bolt with the ears for a hand crank is 1-5/16 across the flats and the thread is 5/8-18 UNF. If the OEM pulley has been replaced with an aftermarket pulley it is probably a standard cap screw which IIRC is 15/16 across the flats.

In either case if it was me I'd bite the bullet and take the front axle support off to get access. Much easier to identify the problem and in all probability you will ultimately wind there.

TOH
 

I have also see them soldered to the hub,,, I had to turn it down to get it apart to make a tool to turn the crank while doing engine work... The center hub was straight with no step to crimp the pulley to...
 
I checked again at lunch and found it to be 15/16". It appears to be tight. Looks like I will be taking some things apart. No better way to learn I guess. I will keep you updated and thanks for all of the help and advice.

Rob
 
(quoted from post at 14:21:55 10/13/14) I checked again at lunch and found it to be 15/16". It appears to be tight. Looks like I will be taking some things apart. No better way to learn I guess. I will keep you updated and thanks for all of the help and advice.

Rob

That leads me to beleive you have the solid steel after market pulley which was designed for use with a shaft driven hydraulic pump. If it is spinning and the bolt is tight either the hub is not aligned with the key or the key is sheared. The first is relatively easy to fix - the latter not so much :(

Here is a picture of the backside of the pulley showing the keyway. It is only about 1/4" long and slides over the front end of the woodruff key in the nose of the crankshaft. The pulley is a very snug fit to the crankshaft and you cannot see the keyway during the installation so getting the keyway and the key aligned and fully seated can be a royal PITA. It is quite possible whoever put the pulley on the tractor never achieved complete "penetration" and you are reaping the fruit of that past failure. ;-)

TOH

Ooops = forgot the picture :oops:

wm_192160.jpg
 
I have learned to listen to others who have experience on a project. I plan on tearing the tractor down slowly and paying attention to detail on this one. I did not see the pic that you mentioned in the post.

Rob
 
The problem is more mysterious than I thought, I took the front end off of the tractor last night and found that I was incorrect, which is not unusual. The pulley, crankshaft gear, and cam gear seem to be fine. I was wrong when I said the bolt was spinning and the pulley not. Actually I had asked my son to tell me if it was. I should have verified. Now the odd part. When the pulley is not turning and the starter is engaged, the flywheel is turning. How is that possible? I had hoped that this would be a starter/bendix issue. But I can't see how. Any advice on this would be appreciated.

Rob
 
(quoted from post at 08:41:03 10/14/14) The problem is more mysterious than I thought, I took the front end off of the tractor last night and found that I was incorrect, which is not unusual. The pulley, crankshaft gear, and cam gear seem to be fine. I was wrong when I said the bolt was spinning and the pulley not. Actually I had asked my son to tell me if it was. I should have verified. Now the odd part. When the pulley is not turning and the starter is engaged, the flywheel is turning. How is that possible? I had hoped that this would be a starter/bendix issue. But I can't see how. Any advice on this would be appreciated.

Rob

I am not following this.
  • [*:d337acd19d]Forget the crankshaft and camshaft gears for now.[*:d337acd19d]The bolt screws into the end of the crankshaft.[*:d337acd19d]The pulley slips over the nose of the crankshaft and is keyed to it.[*:d337acd19d]The flywheel is bolted to the crankshaft.[*:d337acd19d]The starter turns the flywheel which turns the crankshaft, which turns the pulley.[*:d337acd19d]If the crankshaft turns but the pulley does not the key is either missing, sheared, or not engaged with the pulley[/list:eek::d337acd19d]If you can see the gears you must have the pulley and timing cover off. Take a picture of the nose on the crankshaft showing the key and post it.

    TOH
 
(quoted from post at 16:41:03 10/14/14) The problem is more mysterious than I thought, I took the front end off of the tractor last night and found that I was incorrect, which is not unusual. The pulley, crankshaft gear, and cam gear seem to be fine. I was wrong when I said the bolt was spinning and the pulley not. Actually I had asked my son to tell me if it was. I should have verified. Now the odd part. When the pulley is not turning and the starter is engaged, the flywheel is turning. How is that possible? I had hoped that this would be a starter/bendix issue. But I can't see how. Any advice on this would be appreciated.

Rob

Did it run before you took it apart and the only issue was the crank pulley was not turning... Does the front of the crank turn...

I am lost as you are soooooo was it a no start (cranks but no start) that got you to looking at the front crank pulley....
 
(quoted from post at 08:57:15 10/14/14)
I am not following this.
  • [*:6eb64e6b5f]Forget the crankshaft and camshaft gears for now.[*:6eb64e6b5f]The bolt screws into the end of the crankshaft.[*:6eb64e6b5f]The pulley slips over the nose of the crankshaft and is keyed to it.[*:6eb64e6b5f]The flywheel is bolted to the crankshaft.[*:6eb64e6b5f]The starter turns the flywheel which turns the crankshaft, which turns the pulley.[*:6eb64e6b5f]If the crankshaft turns but the pulley does not the key is either missing, sheared, or not engaged with the pulley[/list:eek::6eb64e6b5f]If you can see the gears you must have the pulley and timing cover off. Take a picture of the nose on the crankshaft showing the key and post it.

    TOH


  • I know that I have missed something somewhere so I will tell you what I know and what I have done. Hopefully that will give you some insight. I want to say upfront that I know next to nothing about Ford tractors. So any advice is appreciated.

    1. I remove the hood, radiator, fan, distributor, and alternator.
    2. I removed the 6 bolts holding the front end while using a jack to support the tractor. Then raised the tractor for pulley access.
    3. I removed the crankshaft bolt and pulley. Using a pair of pliers and a screwdriver I checked the key for movement. I found none.
    4. I spun the engine to make sure that the crank and cam both turned. They did. Rechecked to make sure pulley was splined with key. It was.
    5. I reversed the process leaving the radiator and hood off. Spun the engine again. Engine seems hesitant to turn over and sometimes does not. But starter is still spinning. I will reverify if I can see flywheel turning at lunch.

    Thanks for all of your help with this. I really enjoy working on this tractor. It seems simple. This problem is just eluding me. Like I said before, I know I have missed something.

    Rob

    edit: I will try to take some pics tonight and post them tomorrow.
 
(quoted from post at 11:36:29 10/14/14)
(quoted from post at 08:57:15 10/14/14)
I am not following this.
  • [*:8ed3ea0e06]Forget the crankshaft and camshaft gears for now.[*:8ed3ea0e06]The bolt screws into the end of the crankshaft.[*:8ed3ea0e06]The pulley slips over the nose of the crankshaft and is keyed to it.[*:8ed3ea0e06]The flywheel is bolted to the crankshaft.[*:8ed3ea0e06]The starter turns the flywheel which turns the crankshaft, which turns the pulley.[*:8ed3ea0e06]If the crankshaft turns but the pulley does not the key is either missing, sheared, or not engaged with the pulley[/list:eek::8ed3ea0e06]If you can see the gears you must have the pulley and timing cover off. Take a picture of the nose on the crankshaft showing the key and post it.

    TOH


  • I know that I have missed something somewhere so I will tell you what I know and what I have done. Hopefully that will give you some insight. I want to say upfront that I know next to nothing about Ford tractors. So any advice is appreciated.

    1. I remove the hood, radiator, fan, distributor, and alternator.
    2. I removed the 6 bolts holding the front end while using a jack to support the tractor. Then raised the tractor for pulley access.
    3. I removed the crankshaft bolt and pulley. Using a pair of pliers and a screwdriver I checked the key for movement. I found none.
    4. I spun the engine to make sure that the crank and cam both turned. They did. Rechecked to make sure pulley was splined with key. It was.
    5. I reversed the process leaving the radiator and hood off. Spun the engine again. Engine seems hesitant to turn over and sometimes does not. But starter is still spinning. I will reverify if I can see flywheel turning at lunch.

    Thanks for all of your help with this. I really enjoy working on this tractor. It seems simple. This problem is just eluding me. Like I said before, I know I have missed something.

    Rob

    edit: I will try to take some pics tonight and post them tomorrow.


  • I am still a little lost but that is not unusual ;-)

    If the starter is spinning and the engine is not turning the bendix on the starter is not engaged. Not uncommon. Make sure the battery is fully charged because the starter needs to spin "briskly" to engage the bendix.

    But none of that has anything to do with the crankshaft pulley. You had it off and verified the key was intact. Did you verify the pulley was fully engaged with the key whan you put it back on and that the bolt is tight against the face of teh pulley? If so your original problem is fixed.

    TOH
 

I did check and was sure that the pulley was correctly installed. What I am discovering now is that I may have misdiagnosed my original problem, or even fabricated my own:). There is still a problem, it is now down to isolating it as a single issue or multiple issues. I will do some more clinical research as opposed to going with my gut. It seems to have failed me anyway. Headed home for lunch now. I will respond with what I find.

Rob
 
(quoted from post at 12:33:11 10/14/14)
I did check and was sure that the pulley was correctly installed. What I am discovering now is that I may have misdiagnosed my original problem, or even fabricated my own:). There is still a problem, it is now down to isolating it as a single issue or multiple issues. I will do some more clinical research as opposed to going with my gut. It seems to have failed me anyway. Headed home for lunch now. I will respond with what I find.

Rob

Help me out. Exactly what is the current problem now that we have dispensed with the pulley issue?

TOH
 
The current problem is that the engine does not turn over at the same rate as the starter. The crank pulley is not turning consistently. At lunch I verified that the flywheel is turning as it should but the pulley will hesitate and sometimes come to a complete stop due to compression. And if it slows due to compression and the flywheel is still turning as it should then there is an issue between the coupling of the flywheel and the crank. But I can not get my mind around how that could happen. Confusing.

Rob

edit: Have you ever seen a ring gear slipping causing this type of an issue?
edit2: I think that I will make a sharpie mark on the ring gear and clutch plate to check for slipping and do the same on the pulley bolt and pulley. That should let me know if there is any movement and where.
 
(quoted from post at 14:21:16 10/14/14) The current problem is that the engine does not turn over at the same rate as the starter. The crank pulley is not turning consistently. At lunch I verified that the flywheel is turning as it should but the pulley will hesitate and sometimes come to a complete stop due to compression. And if it slows due to compression and the flywheel is still turning as it should then there is an issue between the coupling of the flywheel and the crank. But I can not get my mind around how that could happen. Confusing.

Rob

edit: Have you ever seen a ring gear slipping causing this type of an issue?

Please stop!!! You have conflated have a dozen components in that description.

What stops turning - the ring gear, the flywheel, the crankshaft, the pulley, all of them or some combination of them? They should ALL turn together.

I have never seen a ring gear slipping but others have and in that case the ring gear would keep turning but the flywheel and ALL of the others would stop.

TOH
 

"Conflate", I like that. A new word for today:). I am probably very good at it and now I have but yet another word to be described as.

When I engage the starter I hear the starter turning and see the ring gear turning at a consistent rate. During the compression stroke the crank pulley, water pump, and alternator slow down or come to a complete stop. During this time I do not really hear a change in the starter speed.

Rob
 
Viewing hole on "passenger side" of tractor. There is a hole on both sides but the starter obscures it some on that side.
 
(quoted from post at 15:15:03 10/14/14)
"Conflate", I like that. A new word for today:). I am probably very good at it and now I have but yet another word to be described as.

When I engage the starter I hear the starter turning and see the ring gear turning at a consistent rate. During the compression stroke the crank pulley, water pump, and alternator slow down or come to a complete stop. During this time I do not really hear a change in the starter speed.

Rob

The water pump and alternator turn with the pulley. More "conflation" (sort of) - forget about them. ;-)

If the ring gear can be seen turning while the crankshaft is not you better hope it is a slipping ring gear. The alternatives are not pretty.

A question that has already been asked but not answered:

Does this tractor start and run??

TOH
 
Prepare for another non answer :). Does it run. Sorta. I was able to get it started after a new set of points and plugs two days ago. We drove it up and down the road a couple of times to make sure that the water pump was working correctly. After turning it off, it would not restart. It would seem to fire then quit. At the time I thought a carb issue. I will test that theory with ether later. My conflation is probably due to me thinking that it may be multiple problems at once. Sorry to confuse. The water pump and alternator all turn with the crank pulley. I just wanted to be thorough. You mentioned unwanted alternatives. Can you let me know what they may be? Again, thanks for all of the help on this. I realize you are taking part of your day to answer a guy who seems to not have his head on straight.

Rob
 
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH
 
(quoted from post at 17:46:31 10/14/14)
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH

Problem solved, well problem discovered. The ring gear is loose and slipping on the compression stroke. Used a good light and can now see what is actually happening. Next topic, can you weld it? I got this tractor rather cheap and really just want it to run correctly. I don't want to cut drastic corners, but would like to save money where I can. So is welding it an option at all? I have a good machine shop that could handle the job. If it can be done, can it be done without removing it from the tractor?

Thanks for everything.

Rob
 
(quoted from post at 19:07:19 10/14/14)
(quoted from post at 17:46:31 10/14/14)
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH

Problem solved, well problem discovered. The ring gear is loose and slipping on the compression stroke. Used a good light and can now see what is actually happening. Next topic, can you weld it? I got this tractor rather cheap and really just want it to run correctly. I don't want to cut drastic corners, but would like to save money where I can. So is welding it an option at all? I have a good machine shop that could handle the job. If it can be done, can it be done without removing it from the tractor?

Thanks for everything.

Rob

If they can get to it they can tack weld it. More than one has been "fixed" that way. Of course a 9N has no access to the flywheel but yours apparently does so I am going to punt on this one ;-)

TOH
 
(quoted from post at 19:15:54 10/14/14)
(quoted from post at 19:07:19 10/14/14)
(quoted from post at 17:46:31 10/14/14)
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH

Problem solved, well problem discovered. The ring gear is loose and slipping on the compression stroke. Used a good light and can now see what is actually happening. Next topic, can you weld it? I got this tractor rather cheap and really just want it to run correctly. I don't want to cut drastic corners, but would like to save money where I can. So is welding it an option at all? I have a good machine shop that could handle the job. If it can be done, can it be done without removing it from the tractor?

Thanks for everything.

Rob

If they can get to it they can tack weld it. More than one has been "fixed" that way. Of course a 9N has no access to the flywheel but yours apparently does so I am going to punt on this one ;-)

TOH
have welded more than one through the starter mounting hole. Piece of cake.
 
(quoted from post at 19:28:13 10/14/14)
(quoted from post at 19:15:54 1

If they can get to it they can tack weld it. More than one has been "fixed" that way. Of course a 9N has no access to the flywheel but yours apparently does so I am going to punt on this one ;-)

TOH
have welded more than one through the starter mounting hole. Piece of cake.

DOH!!!
 
Awesome. That is what I wanted to hear. I will let you know how it goes. From loose pulley to slipping ring gear. I have to say that this is excellent support. Thanks to everyone for the advice.

Rob
 
(quoted from post at 03:07:19 10/15/14)
(quoted from post at 17:46:31 10/14/14)
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH

Problem solved, well problem discovered. The ring gear is loose and slipping on the compression stroke. Used a good light and can now see what is actually happening. Next topic, can you weld it? I got this tractor rather cheap and really just want it to run correctly. I don't want to cut drastic corners, but would like to save money where I can. So is welding it an option at all? I have a good machine shop that could handle the job. If it can be done, can it be done without removing it from the tractor?

Thanks for everything.

Rob

That's great cuzz I could not keep up with the info as you went back and forth with useless comments and knew you were in good hands...

BTW one of biggest fudge ups was missing the center broke out of a auto flywheel... It was a 2.5 chebby FWD they were notorious for stripping the cam gear when you heard it spin with no compression... I was banking the money every time I ran across one it was a EZ kill it takes me about 2 hr to R&R the cam gear it paid very well because you are suppose to remove the engine, head and cam (By the book)....

The last one I did I jumped right into it,,, Problem was I did not look to see if the crank pulley was turning :cry:
 
(quoted from post at 19:46:03 10/14/14)
(quoted from post at 03:07:19 10/15/14)
(quoted from post at 17:46:31 10/14/14)
(quoted from post at 15:59:34 10/14/14) You mentioned unwanted alternatives. Can you let me know what they may be?

Rob

No - I don't want to introduce any additional confusion into the discussion. Here is what I suggest - forget the pulley and associated components up front. That looks to have been a trip down a one way street in the wrong direction. Work on getting the engine to crank off the starter. If the ring gear is slipping you need to verify that before you go off in any other directions.

TOH

Problem solved, well problem discovered. The ring gear is loose and slipping on the compression stroke. Used a good light and can now see what is actually happening. Next topic, can you weld it? I got this tractor rather cheap and really just want it to run correctly. I don't want to cut drastic corners, but would like to save money where I can. So is welding it an option at all? I have a good machine shop that could handle the job. If it can be done, can it be done without removing it from the tractor?

Thanks for everything.

Rob

That's great cuzz I could not keep up with the info as you went back and forth with useless comments and knew you were in good hands...

BTW one of biggest fudge ups was missing the center broke out of a auto flywheel... It was a 2.5 chebby FWD they were notorious for stripping the cam gear when you heard it spin with no compression... I was banking the money every time I ran across one it was a EZ kill it takes me about 2 hr to R&R the cam gear it paid very well because you are suppose to remove the engine, head and cam (By the book)....

The last one I did I jumped right into it,,, Problem was I did not look to see if the crank pulley was turning :cry:

I wouldn't say useless but not very useful :D. I knew what I was talking about :). All joking aside. You guys saved me a lot of time. I thank you.
 
One last question. How many teeth are on the 9n ring gear? I need to figure out where to put my welds. I guess 4 would be enough set at quarters on the gear. Let me know what you think.

Rob
 
(quoted from post at 09:39:22 10/15/14)
134 I think

If my math is correct then I will weld at tooth 1, 33.5, 67, and 100.5. Do you think a 1/2 inch weld would be too much at each location? Will the weld weight make that much of a difference?

Rob
 
(quoted from post at 12:53:39 10/15/14)
(quoted from post at 09:39:22 10/15/14)
134 I think

If my math is correct then I will weld at tooth 1, 33.5, 67, and 100.5. Do you think a 1/2 inch weld would be too much at each location? Will the weld weight make that much of a difference?

Rob
did more. Probably every 1/8 th turn. But whatever works.
 
(quoted from post at 18:29:18 10/15/14) One last question. How many teeth are on the 9n ring gear? I need to figure out where to put my welds. I guess 4 would be enough set at quarters on the gear. Let me know what you think.

Rob
4 places as evenly spaced as you can... 1/2" long weld would be a over kill and OK,,,, it does not take much to hold it.... 1/4" will do it...
 
(quoted from post at 13:09:46 10/15/14)
(quoted from post at 18:29:18 10/15/14) One last question. How many teeth are on the 9n ring gear? I need to figure out where to put my welds. I guess 4 would be enough set at quarters on the gear. Let me know what you think.

Rob
4 places as evenly spaced as you can... 1/2" long weld would be a over kill and OK,,,, it does not take much to hold it.... 1/4" will do it...

Thanks for the info. I will post some pics when done.

Rob
 

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