Heymow - Lawnmower Racing Forum

Engine Help => Briggs OHV & Vanguard => Topic started by: huntersdad on September 28, 2009, 10:14:26 pm

Title: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 28, 2009, 10:14:26 pm
Im new to the sport and just had a question on my output shaft I have the drive and blade pulley on the same shaft the pulleys seem to be welded as if they are one unit I was wanting to swap the drive pulley but cant seem to get the stock one off is there anything else that can use to bypass this
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 28, 2009, 11:33:08 pm
they are one unit, and if you building a racer, the blades and all the drive for the deck should be long gone!!
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 28, 2009, 11:43:28 pm
yes they are. The issue i have is that i want a little bigger than stock on the drive pulley I Had thought of cutting the lower part of the shaft off that has the blade pulley on it but I was needing to get rid of the stock drive pulley first somehow
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 28, 2009, 11:47:06 pm
Is this a racer you are working on?
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 28, 2009, 11:51:25 pm
Yes thats what I was hoping to accomplish but Im stuck at the very beginning of the build I tried asking questions at the local mower shop but they werent very helpful I need to get pass this so I can go deeper into the build
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 28, 2009, 11:55:07 pm
not to discourage, but the beginning of the build should be chassis work, steering work, brake work, related safety gear, etc......
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:01:27 am
yep and to do the chassis work it is helpful to have the motor out of the way, therefore;

It sounds to me like you have just started to tear down a mower. The stacked drive pulley should be a 1" keyed bore unit. It will seperate from the shaft end of the crank with a bit of work. There should be a bolt/washer on the very bottom after removing that you can soak the shaft with penetrating oil (like PB Blaster) After that has soaked in for a few hours/days it may simply slide off. If not you can carefully cut through the pulleys and the bore and split the thing open to remove it. You have to be carefull when cutting not to score the PTO. I always try to line up my powered hacksaw with the keyway so if I go to deep I score the key and not the shaft.
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:04:25 am
I totally agree but  having all that accomplished and no way to put power to the tires would be like a tank with no engine so to speak what I was hoping to do was to atleast have the drive-train or atleast a start of one then break it down and then do the mods It would be alot of work not knowing first if it would even move
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:07:49 am
No no no you can't simply trust that the original factory steering and brakes are gonna stay together, they are too weak. Tear it down and build it back up as real machine, it will move just fine. Make it safe BEFORE you make it fast, PLEASE. As your nik says Hunter NEEDS his dad!!!
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:11:34 am
toadworks both the drive and blade pulley seems to be welded to the output shaft the keyed part looks to be that the output shaft has been stamped as to create a dove tail configuration that slides onto the crankshaft
I am in no way going to even try to run it at speed at all if any thing just far enough as to say awww ok thats what i needed I have some tubing that i will be using for the bracing
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:16:00 am
If the stacked drive pulley is welded to the PTO then I'd just leave it alone. I'm thinking some one else worked on it that "patched" it back together??
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 29, 2009, 12:17:51 am
they can be real stubborn to get off, if its welded on by a previous owner, take a hand grinder and ground the weld off!
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:23:50 am
believe me i tried that already seems that it was tacked to hold it then welded  The guy at the mower shop told me that what i have was sold as a unit and they could not be removed independantly this mower belonged to my father who bought it new and I dont know of him having it welded hes not the type to (RIG) anything
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:28:22 am
Are you trying to just remove one pulley from the stacked unit?
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 29, 2009, 12:32:54 am
they are one piece!! to get one off you take both off!!
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:38:30 am
I wanted to remove both and replace the drive pulley with one that was a little bigger and hopefully cut the excess off of the output shaft just under where the bolt goes to reattach the pulley to the crankshaft that way I should have plenty of clearence from the ground when I lower my mowchine
But how by cutting  them
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:39:25 am
go to this link....  the pictures show a transaxle,  but the idea is the same. What you have is simply an old stacked drive pulley that is stuck to the PTO. And don't cut the PTO as it is part of the machining of the crankshaft......

http://acmemowersports.com/how_to_remove_a_pulley.html


Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:46:08 am
is that a saw blade????/ but Im serious when i say that the pulleys are welded I mean they realley are its not a figure of speach there is a definate weld bead going from the innerside of the pulley to the shaft
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: jerb on September 29, 2009, 12:51:35 am
is that a saw blade????/ but Im serious when i say that the pulleys are welded I mean they realley are its not a figure of speach there is a definate weld bead going from the innerside of the pulley to the shaft
if there's a bead they are welded on, take an angle grinder and grind on the end of the crank till the weld is gone, and the crank does not need to be shortened even on a 4'' frame height!
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 12:56:04 am
Okay, the first step is for you to remove the two pulleys that are welded together (the stacked drive pulley) It's just stuck. it will come off, you may have to resort in cutting it parallel to the PTO and splitting it open to get it loose, but you may find that some penetrating oil and some time will allow it to slide off easier.

After removing the pulley, do us all a favor and continue to disassemble the mower, install better steering, better brakes, bolt the wheels on (snap rings alone won't work) aand install a tethered kil switch after that has been accomplished THEN and only THEN change the gear ratio to make it go faster. And then before you drive down the street... get your safety gear on, helmet, long sleeves, pants, boots, neck collar

I have a feeling that the moderators will be locking this thread down soon. We really do stress the importance of SAFETY and doing things like a simple pulley change and tearing off down the street to see how fast it goes is something that is frowned upon severely here. It will get you banned from the site. So if you want to contiue to get help, you need to make sure we understand that you are just as rule oriented and safety conscious as the rest of us.

 
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 12:58:21 am
well if i am successful at getting them off is there a pulley that can be welded back in its place one that is completley round with no key
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 01:03:17 am
no a smooth bore won't work, you need the key to "lock" the shaft of the PTO and they hub of the pulley together.

I think what you are seeing is the end of the hub on the the top pulley, and the weld you see is at the top of the bell hub of the lower pulley. the bolt that you took out is at the end of the PTO shaft. Everything that sticks out lower than that bolt can be cut any old way you want.
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 01:16:43 am
Well Like I said before Im not looking to go down the street just to see how many cars i pass all i want to do is start the motor feel it go into gear and dismount tear it down and rebuilt it the right way  I am very safety savvey  I just dont want you guys to think that way because im a newbie but I thank you for your concern. Since I have no experience at this I dont know if it will work until i try it first..

I have already removed the stack pulley and i can see that they are indeed welded there is no hub that im aware of either if I could I would like to post pics tommorrow oh and also my pulley does not have a key  the inside of the input is the key its punched in
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: GTX21 on September 29, 2009, 02:37:07 pm
Well Like I said before Im not looking to go down the street just to see how many cars i pass all i want to do is start the motor feel it go into gear and dismount tear it down and rebuilt it the right way  I am very safety savvey  I just dont want you guys to think that way because im a newbie but I thank you for your concern. Since I have no experience at this I dont know if it will work until i try it first..

I have already removed the stack pulley and i can see that they are indeed welded there is no hub that im aware of either if I could I would like to post pics tommorrow oh and also my pulley does not have a key  the inside of the input is the key its punched in
Thats why you buy a pulley that has a keyway in it and get a key thats big enough to fit in the crank and the pulleys key way
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 05:03:09 pm
So by what your saying do I just trash what I have and find a pulley that goes directly on the shaft of the motor,the shaft itself is grooved fron the bottom up to the base of the motor and by doing that I will need spacers or bushings to hold the pulley in placce right????????
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 05:46:47 pm
Pictures please. You still have me confused by what you are describing as the information in the PM you sent me is different than the info posted here.

Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 05:53:10 pm
going now to snap a few ill post them asap
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on September 29, 2009, 07:35:36 pm
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild001.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild002.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild003.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild004.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild005.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild006.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild007.jpg)
(http://i874.photobucket.com/albums/ab309/huntersdad1/Lawnmowerbuild008.jpg)
the pulley on top is bent because I thought that I could beat it off guess not
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: Toadworks on September 29, 2009, 07:48:35 pm
Okay what we have here is failure to communicate.

You have successfully removed the pulley, now find the recycle bin and toss it in. The shaft that is left at the bottom of the motor is just what it should be a 1" diameter keyed shaft. You will purchase a new 1" bore keyed pulley that will slide onto the PTO and be secured by the bolt and washer that you removed to take the stacked drive pulley off. You will also need a key since the key in your original hub of the stacked pulley is stamped in.

I see what you were trying to do now and that is to keep and re-use the hub from the stacked pulley set. You don't need that part.

Here is an example of a new pulley;

https://www.surpluscenter.com/item.asp?UID=2009092918551505&item=1-BK45-E&catname=powerTrans
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: overkillphil on October 09, 2009, 03:27:15 pm
The original bolt and washer will undoubtedly be useless for the new pulley you will be purchasing.  You will need a couple of shaft collar locks as I would not rely on the dinky little allenhead set screw that comes with cast iron pulleys.  BTW, I would try to find some steel pulleys or get some good aluminum ones from EC.  I don't like the heavyness of the cast iron pulleys, especially when they start getting larger in diameter.  They are like a giant cast iron flywheel and it makes it harder to slow the engine down abruptly.
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on October 12, 2009, 09:53:01 pm
I went by tractor supply to look at there pulleys they had some good steel ones,,, they had the 3in but were out of the 6in so I left with neither. I want a matching set...
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: GTX21 on October 12, 2009, 11:30:02 pm
The lowest i would go, and most on here would go is a 4.
Title: Re: Drive pulley on a 18hp briggs and stratton I/C
Post by: huntersdad on October 13, 2009, 06:11:45 pm
Good info atleast thats one mistake I dont have to make when selecting pulleys