[greencharger68]

help 86 350 fourtrax
i am trying to help a guy who has cancer. he uses the atv to get around on his farm. the front axle clunks when riding or more when turning.
i drained the diff fluid and replaced, no metal chips. the cv has grease. removed drums and cleaned.

? how to check shafts and cv, ? where else to look.
thanks [email protected]

1968 CHARGER R/T 440 Magnum

 

[Helmut]

Welcome to the forums. Try to get a hold of the axles with your hand and see if you can move or wiggle them. They should be good and tight. Also, the hub bearings could be bad where the axles go through the hubs. When Shadetree gets on here, he will probably be able to help you more. He has a Fourtrax 350 that he just rebuilt and restored and he is more familiar with them, than I am.

 

[greencharger68]

thanks should the bike be on the ground?

 

[Helmut]

thanks should the bike be on the ground?

Yeah, if it's sitting on the ground, you should be able to grab the axles and try to wiggle them and they shouldn't move.

 

[shadetree]

i heard my name ???..lol

 

[Helmut]

i heard my name ???..lol

Yeah, you're probably more familiar with the Fourtrax 350 than anyone else on here, since you just finished restoring yours.

 

[shadetree]

help 86 350 fourtrax
i am trying to help a guy who has cancer. he uses the atv to get around on his farm. the front axle clunks when riding or more when turning.
i drained the diff fluid and replaced, no metal chips. the cv has grease. removed drums and cleaned.

? how to check shafts and cv, ? where else to look.
thanks [email protected]

1968 CHARGER R/T 440 Magnum

first off, welcome to the forums...if you can..jack the bike up..all 4 wheels need to be off the ground...with the bike in neutral...put the steering facing straight..spin the front tires..does the sound come from the wheels ?..or does it come from the front differental ?....put the bike in 1 st gear..now..rotate one of the front wheels back and forth....any cluncking sound ?..i really need to know where it's comming from..it could be the bearings..or cv joints..or the front differental..kinda hard to tell you what your problem is..without knowing this.

 

[shadetree]

i heard my name ???..lol

Yeah, you're probably more familiar with the Fourtrax 350 than anyone else on here, since you just finished restoring yours.

yup..i'm pretty much on top on my trx350d foreman..lol..inside an out..lmao.

 

[greencharger68]

ok thanks i will try all that this weekend.

 

[shadetree]

ok thanks i will try all that this weekend.

i'm sorry i couldn't be more help to ya..but..without knowing where the sound is comming from..i can't tell you how and what to take off or fix..if i knew where it was comming from..i could tell you what you will have to do in order to fix it...but..from what you stated..i can almost guess it's either your front cv joints..or front differental..and let me tell you..it took me about 1 hour to remove the whole front end on mine..i had to over haul the front differental..seals..bearings..pinion...ring gear..pretty much all of the front differental..sooo..be ready to do some long work in getting it tore out..tore down..and back together..and make sure you got some pretty big sockets...you will need them to remove the outter knuckles..if your going to repair the front differental..you will need some spec tools to do it..soo..wait until you do what i asked you to check..and get back to me..we'll take it from there.

 

[69quadracer]

Shadetree knows his stuff, sounds like cv joints.

 

[greencharger68]

does the sound come from the wheels ? ok off the ground wheels front, spin wheels no sound.
also ran engine/wheels in air no sounds straight or turning.

does it come from the front differental ? no sound

put the bike in 1 st gear..now..rotate one of the front wheels back and forth.any cluncking sound ? no sound again.

pulled wheels and hub took a look at the bearings seems ok, turned bearing with screwdriver right side seemed stuck but got loose after turning it a few times. also tried turning the wheels with them turned in each direction, still no sound, seems that it will only clunck under load or with weight on wheels. the sound is more like gear slipping and it does it with the engine off also, we pushed it and it does it in all positions, very hard to locate exact location i think it is on the left side or in the diff.

thanks again

 

[Helmut]

It could be the carrier bearing for the front driveshaft. I've replaced those before and it sounded like the front ring and pinion gears were stripped, because the driveshaft would move up and down. It's #8 in the diagram below.

 

[greencharger68]

we put the bike back together and on the ground, still makes the sound.
But... very strange if you grab and lift the rear of the bike and swing it to either side it makes the sound but the wheels are not being rolled forward or back. they are turned as if turning the bike. the sound is much faster and sounds much more like ring and pinion gears slipping. sounds like rubbing comb with your thumb but heavy metal sounding. i changed the diff and did not find any metal.
after much discussion with my son we are thinking that the bearing #8 is worn, that shaft will have room to move and cause it to slip on the ring gear.
does that sound possible?

do you have a diagram of the diff gears.
a sad note all this is because someone had ghost road the mans electric golf cart into his lake. that is why we are helping him.

 

[shadetree]

ok..i may have an idea where your prob is....after tearing down the front on mine.. < the front diff was shot > i replaced everything in the front diff...i replaced both outter knuckle bearings..there is two..top and bottom of the knuckle...then i replaced the swing arm bearings..most of the time they are bad if the bike is really old....well..i had a problem something like your talking about with this bike your working on...i could grab mine from the rear rack..roll it back and forth..and i kept hearing a clunking sound..well..i knew it wasn't the front..after hearing it up close..i thought it was the out put shaft..well..i took it out..checked it..it was ok..sooo..from the very front..to the out put shaft..all was either replaced..or checked by me...i already had replaced the rear swing arm bearings earlier..sooo..i knew it wasn't those...only thing that was left...was the rear differental...i tore the rear diff out...sure enough..the ring gear..and pinion gear...and all the bearings were bad...i ordered new bearings and seals...found me a ring gear and pinion gear from a friend..put it all back together..and i don't hear any more clunking, bottom line here is..just because you think the nosie is comming from the front..does not mean thats where your problem is.

 

[Helmut]

When you lift the back end up and move it side to side, check the front swingarm bearings and see if they're bad. Also, check the front driveshaft for movement and there should be a u-joint somewhere on the front driveshaft that could be bad making the noise. One more thing to check would be the splines where the front driveshaft splines onto the front pinion shaft on the front differential. The splines could be stripped. Here is the diagram of the front differential and gears.

 

[shadetree]

also would like to add..there is a lower stearing arm bearing..it could be bad...it sit's in a u-shaped craddle at the bottom of the stearing arm...you will need a spec tool to unscrew the odd size nut out in order to knock the bearing out..if it's not to bad..you maybe able to just work it loose..repack it with grease..and reinstall..if it's really bad..just purchase a new one..if this bike is hard to turn while sitting still..and makes this noise..more than likely the bearing is bad.

 

[greencharger68]

sorry shadetree but... you made me laugh and i have a big smile now.
when my son moved the bike he had the rear wheels lifted off the ground and the bike was not running that is what we found strange.

i understand what your saying, we will return the bike and have him just drive it, he is not gonna beat on it anyway. if later it breaks we can work on it again. because it sounds like we would need to replace parts anyway so may as well use the old ones up.
it was not running when we got it and it runs ok now and the engine is very quiet now that we changed the oil. we fixed the brakes replaced broken missing hardware and just cleaned it up for him.

thank you all for the help
Gods blessings to you.

 

[greencharger68]

helmut
thank you
i will check them as well. before returning it to our friend.

 

[Helmut]

helmut
thank you
i will check them as well. before returning it to our friend.

You're welcome. I hope you get it figured out and I hope it's something simple.