Tapered pin bolts

[GTA]

So I just noticed that the tapered pins at the bottom of my bobtach have loosened up a bit. It appears the bolts have backed off slightly. If I put a screwdriver behind the bolt head I can reseat the taper which requires a small hammer tap to release. However, I cannot tighten the bolts without the pin spinning free, even with an impact gun. Does anyone have a suggestion of how to tighten these or remove them. Thanks.

 

[SkidRoe]

Sounds like the pins will have to come out. You will need to drill or torch off the heads of the bolts, then take out the grease fittings on the lower bobtach pivots. You should then be able to push the pins into the housings to release the bobtach from the boom. If the tapered bores in the ends of the boom are worn, they can be reamed. HTH - SR

 

[farmshop]

Sounds like the pins will have to come out. You will need to drill or torch off the heads of the bolts, then take out the grease fittings on the lower bobtach pivots. You should then be able to push the pins into the housings to release the bobtach from the boom. If the tapered bores in the ends of the boom are worn, they can be reamed. HTH - SR

I would try to seat the pins by wedging something behind the head and spinning with a impact. If it won't come out then cut the head off. Take out the grease zerk and pound the pins in. When installing the new ones get a piece of threaded rod to pull the pins in before installing the bolts

 

[Tazza]

I would try to seat the pins by wedging something behind the head and spinning with a impact. If it won't come out then cut the head off. Take out the grease zerk and pound the pins in. When installing the new ones get a piece of threaded rod to pull the pins in before installing the bolts

Another way i have done it is to load the bucket, this will put a lod on the pins and you can generally tighten it up.
I had my dad help me with one machine like this. I drove up to a tree and pushed against it, he swung on the bar to tighten up the bolt, it worked very well.
With all this said, if there is grease between the tapers, there is a chance it will un-do again later. If you can tighten it up to get the taper to lock, you can then un-do it to clean the taper surfaces to do it right.

 

[GTA]

Another way i have done it is to load the bucket, this will put a lod on the pins and you can generally tighten it up.
I had my dad help me with one machine like this. I drove up to a tree and pushed against it, he swung on the bar to tighten up the bolt, it worked very well.
With all this said, if there is grease between the tapers, there is a chance it will un-do again later. If you can tighten it up to get the taper to lock, you can then un-do it to clean the taper surfaces to do it right.

So it looks like replacement is the best option. What I'll do, when the snow season ends, is cut the heads off and push the pins. When I do this, does the bolt have to be cut flush with the pin or is there ample room in the bobtach to receive the pin and a short length of the bolt? Also, if the holes do need to be reamed where can I get the tool to do so? What I did for a temporary solution, and to prevent further wear, was cut a slot in a washer that was a tight fit behind the head of the bolt and used a hammer and punch to put into place. This tightened everything up so there is no movement. I tried an impact gun after installing the washers but still no luck. The taper will only hold about 40 lb/ft. I'll try again next time I have a load in the bucket. I only use the machine about 10 hours a year, and its light duty work, so I'm not terribly concerned about worsening anything before I take it apart. Thanks again for everyone's help. George.

 

[farmshop]

So it looks like replacement is the best option. What I'll do, when the snow season ends, is cut the heads off and push the pins. When I do this, does the bolt have to be cut flush with the pin or is there ample room in the bobtach to receive the pin and a short length of the bolt? Also, if the holes do need to be reamed where can I get the tool to do so? What I did for a temporary solution, and to prevent further wear, was cut a slot in a washer that was a tight fit behind the head of the bolt and used a hammer and punch to put into place. This tightened everything up so there is no movement. I tried an impact gun after installing the washers but still no luck. The taper will only hold about 40 lb/ft. I'll try again next time I have a load in the bucket. I only use the machine about 10 hours a year, and its light duty work, so I'm not terribly concerned about worsening anything before I take it apart. Thanks again for everyone's help. George.

There should be enough room to leave some bolt. If the boom tapers need to be reamed dealers have tools don't know how much they are we just have the dealer do it. I have fixed up tAper holes with the mig welder and die grinder to get by.

 

[Tazza]

There should be enough room to leave some bolt. If the boom tapers need to be reamed dealers have tools don't know how much they are we just have the dealer do it. I have fixed up tAper holes with the mig welder and die grinder to get by.

You really need more power than an impact. I used a 3/4" socket set with a length of water pipe. That puppy was really tight.

 

[7LBSSMALLIE]

You really need more power than an impact. I used a 3/4" socket set with a length of water pipe. That puppy was really tight.

in order to remove pin bolts . tapered pin has spun in ldr arms.. Loctite is what is holdining bolt to pin. heat end of bolt let heat set in ten.mins or so this will soften the Loctite. or glue so to speak. now put a chunk o wood between bobtach and arms tiltback till board is crushed. hit with an impact should come out, that will get it apart.. now unless you match the the female hole on the ldr arms to accept tapered pin youre going to go thru this again and again. the to to recut taper in arms is about 500 bucks. takes about two hrs of solid work to do both sides. (basically what we dohere is retaper female side in ldr arms) side note, that is if still within spec. . ive seen many a try and fail at this . always without the retaper of ldr arms. as I new pins in but it wont hold. BCD might have some tricks . but me goining to drop tach. ream arms replace busch in tach renew allworn parts etc . from here on if greased.. lifetime of unit. never got to dickaround again. or patch patch patch . until youre welindining and line borining

 

[7LBSSMALLIE]

in order to remove pin bolts . tapered pin has spun in ldr arms.. Loctite is what is holdining bolt to pin. heat end of bolt let heat set in ten.mins or so this will soften the Loctite. or glue so to speak. now put a chunk o wood between bobtach and arms tiltback till board is crushed. hit with an impact should come out, that will get it apart.. now unless you match the the female hole on the ldr arms to accept tapered pin youre going to go thru this again and again. the to to recut taper in arms is about 500 bucks. takes about two hrs of solid work to do both sides. (basically what we dohere is retaper female side in ldr arms) side note, that is if still within spec. . ive seen many a try and fail at this . always without the retaper of ldr arms. as I new pins in but it wont hold. BCD might have some tricks . but me goining to drop tach. ream arms replace busch in tach renew allworn parts etc . from here on if greased.. lifetime of unit. never got to dickaround again. or patch patch patch . until youre welindining and line borining

misprint the tool ( reamer bit) IS COSTLY.

 

[7LBSSMALLIE]

misprint the tool ( reamer bit) IS COSTLY.

DONE ONCE DONE RIGHT, GREASED ID SAY DAILY but it aint goining to happen. should last lifetime of unit.

 

[GTA]

DONE ONCE DONE RIGHT, GREASED ID SAY DAILY but it aint goining to happen. should last lifetime of unit.

So today I put a jack under the bobtach and put some pressure on the pins. Using an impact gun, I snugged one up and then used a breaker bar to send it home. The other side still won't go though. I think I'll try warming the bolt up to loosen the locktite and try again. When I do take this apart after the snow season I'll do it right. I read in another post here that the pin taper is 1.5 inch per foot and that I can use a ball joint reamer to clean the arm bores. Is this information right?

 

[GTA]

So today I put a jack under the bobtach and put some pressure on the pins. Using an impact gun, I snugged one up and then used a breaker bar to send it home. The other side still won't go though. I think I'll try warming the bolt up to loosen the locktite and try again. When I do take this apart after the snow season I'll do it right. I read in another post here that the pin taper is 1.5 inch per foot and that I can use a ball joint reamer to clean the arm bores. Is this information right?

Could someone tell me what the bolt length is that secures the pins? Also is it a 5/8-11 thread? I'd like to source some new hardware and Nordlock washers for when this comes apart. Thanks, George.

 

[SkidRoe]

Could someone tell me what the bolt length is that secures the pins? Also is it a 5/8-11 thread? I'd like to source some new hardware and Nordlock washers for when this comes apart. Thanks, George.

What machine model are we talking about?

 

[GTA]

What machine model are we talking about?

Sorry, it's an 853.

 

[SkidRoe]

Sorry, it's an 853.

Parts catalog says it is 4.5" long, but does not indicate the size. 5/8" sounds like the correct ballpark. Smaller machines use 1/2" bolts.
What size wrench do your current bolts take? If they are regular hex head bolts, a 5/8" bolt should take a 7/8" wrench.
HTH - SR

 

[GTA]

Parts catalog says it is 4.5" long, but does not indicate the size. 5/8" sounds like the correct ballpark. Smaller machines use 1/2" bolts.
What size wrench do your current bolts take? If they are regular hex head bolts, a 5/8" bolt should take a 7/8" wrench.
HTH - SR

The head is flanged and takes a 1 1/8 socket.

 

[SkidRoe]

The head is flanged and takes a 1 1/8 socket.

An 1-1/8" head would typically make it a 3/4" bolt, but sometimes flange head bolts have odd sized heads.

 

[farmshop]

An 1-1/8" head would typically make it a 3/4" bolt, but sometimes flange head bolts have odd sized heads.

Most are 5/8. Although I think I have seen some 3/4