[marlinman]

Hi all, not exactly new here, but it has been years, and username and password glitches kept me off, but I think I have it all resolved.

I posted here before about a 98 250 Foreman and you guys were very helpful. That one is still with me and runs fine.

Recently I bought a 86 TRX350 4x4. Has been very good so far, with one issue. On a ride with some friends the RF wheel started smoking. Long story short, the wheel bearings were loose and causing a lot of heat. I THINK this heat boiled some of the brake fluid because the front brake lever had zero effect and went easily to the grip.

Fast forward, I muddled my way through understanding how to get the front knuckle apart, but finally figured out the top ball joint has to be unscrewed. Very interesting design.

So yesterday, I installed the new bearings in the RF and started re-assembling the front end. I decided to try to get the brakes going again, and see if anything was ruined from the heat. That brings me here.

As FAR AS I CAN TELL there is no damage to the rubber parts in the brakes. Nothing leaks, but it acts like there is air in the line. I bled the RF for quite a long time, and I can pump it rapidly and get a solid stop, about halfway to the grip. It holds this under pressure. I tried adjusting the shoes and it doesn't seem to help bring the lever out nor keep from having to pump it.

I know bleeding the air from the Foreman I had a LOT of trouble getting the air out but finally did it.

Looking for suggestions on this new (to me) beast. Something I am not trying on these brakes?

Thanks

 

[retro]

First of all, it sounds like you have been working without a service manual? You can get a copy HERE if you need one. Its a must-have resource...

There is a sticky on bleeding brakes HERE on this site in the brakes & suspension forum to help you get that issue sorted out.

If you need any help just ask...? lots of helpful, knowledgeable folks here! We like the old TRXs too!!!

Keep us informed...

 

[hodge5]

Some photos of your 350 would be appreciated!

 

[shadetree]

air in the line.

 

[marlinman]

Yea I know there is still air, it's a PITA to get out too.

Here is an AFTER picture. When I got it, it was rusty everywhere, and painted 3 different colors. I got all the paint off of it and removed, sanded and painted all the rusty metal parts. The racks looked HORRIBLE with all the rust, but cleaned up real nice.

Right now it is in my workshop with the front end all apart.

Everything works, and when I bought it, the guy said it was kick start only. Once I confirmed that it HAD elec start, I went to look at it. After a test drive, I worked up a price with the seller and took it home.

The starter, he thought had a bad bendix. Hmmmm, when I hit the button it made a slight grind noise, then sounds like very light grinding and freewheeling at the same time. Very odd.

SO I traced down the wiring to see if parts were bad, and had to scratch my head. Research, head scratch again, and more research. It LOOKED like the main wire and ground were reversed but no, Honda HAD to have done something weird that year. So after finding nothing to prove that theory, I rewired it and gave the button a quick push, cranked that engine over like no body's business. By the way, there is NO bendix, as I am sure you guys know. It's a sprag bearing that only turns one way, thus the spinning grinding noise. Hasn't hiccuped since.

Thanks for the link, and I had tried but could not find a manual. That will be helpful.

 

[marlinman]

OK I read the sticky on bleeding the brakes. Maybe I am missing something, but using the vice grips to open and close the line, seems no different than opening and closing the bleeder valve. Am I missing something?

I only, finally got the air out of the 98 that I have by reverse feeding the brake fluid. Someone suggested that it it worked real well and faster. It made sense to me, since air bubbles will rise in a fluid, so make them go the natural direction. Even after settling for a few hours I would tickle the brake lever and you could see tiny bubbles surface in the reservoir.

I have not tried it on this one yet, but am about to.

 

[marlinman]

Here is a video of what I was talking about.

 

[shadetree]

OK I read the sticky on bleeding the brakes. Maybe I am missing something, but using the vice grips to open and close the line, seems no different than opening and closing the bleeder valve. Am I missing something?

I only, finally got the air out of the 98 that I have by reverse feeding the brake fluid. Someone suggested that it it worked real well and faster. It made sense to me, since air bubbles will rise in a fluid, so make them go the natural direction. Even after settling for a few hours I would tickle the brake lever and you could see tiny bubbles surface in the reservoir.

I have not tried it on this one yet, but am about to.

the reason for the vice grips : is your closing off right there at the master cylinder, easier to put pressure with lever. once you master the vice grip pressure ?, it's all down hill from there. been doing it this way for many , MANY years. not once have I NOT got my brakes bled, and working this way.

 

[retro]

Nice looking 350!!! Great backstory too, thanks for sharing all that!

EDIT:
Shadetree beat me to it... I'll leave this all here though. Thanks shadetree!

To help answer your question about bleeding the brakes... those old machines can be a bugger to get all the air out of the system. So by putting a clamp on the brake hose and pumping the master, you will begin to move trapped air downward toward the bleeders while not allowing any of that air to return. The clamp acts as a check valve that you can continually relocate further away from the master as you are bleeding... forcing trapped air ahead of the clamped hose and closer to a bleeder where it can eventually escape. Follow me...?

Back bleeding may work very good too, particularly if your method/device provides a lot of volume, yet is low pressure... those types can generally return the brake fluid to a reservoir where it won't be wasted, once you are sure that all the old fluid has been flushed out, of course.

One little tip (or two?) for you that may increase your luck... there is a small round, rubber "check valve" in the bottom of the master cylinder reservoir. It has "X" shaped slits in its thin membrane to allow fluid to flow into the master cylinder bore, but it also serves to trap air in the master while you are trying to bleed it. So, reach in there and remove that small rubber valve before you begin to bleed, then put it back just before you finish up with the final few pumps. It will help the job go faster... also loosen the handlebar clamp and level up the master cylinder assembly best as you can while bleeding, then after the lid is back on you can put it back where it belongs.

 

[SamUK]

Back bleeding would be the ideal way or you can pressure bleed from the MC, you'll need a spare MC top/cover to drill and tap though for that.
There was mother thread about bleeding brakes recently and I'm sure @retro mentioned lifting the front or rear (depending where the bleed screw is) of the ATV/vehicle. I'd never thought of doing this before but it is a GOOD idea indeed.

Hope you get those brakes working, keep us posted

 

[marlinman]

I have to say, due to the age of this quad I am leery of using vice grips. Lord knows how hard finding a brake line might be. I think I am going to stick to my back bleeding for that reason. I will post when I get it going.

I have thought of making a false cap even for back bleeding, and that way I don't have to keep siphoning it out of the reservoir to prevent overfilling. I will post that too if I do it. I didn't on the other quad and it was a PITA, especially when I forgot to siphon.

Thanks for the valve tip. That will make it all easier.

One thing I have noticed about this bike over the 98 250 Recon we have. The 250 will run circles around the TRX350, but I assumed it was due to less weight and drivetrain loss. Does this sound reasonable? The TRX does not miss and it will scoot when I push it, but the little Recon just comes out of the hole a lot quicker. I don't race it at all, but it is an observation. It also seems like the TRX is geared lower, since first gear winds out pretty fast.

 

[retro]

Ya, the TRX350 weighs in at about 570 lbs dry... so about 600 lbs with fuel and oil and battery in it. The Recon...? I'd be guessing... less than 360 lbs or so..?

The 350 is geared way lower too. It was designed to be a workhorse, was the best in its class when it was made. The 350 is way overbuilt... to be tough and durable and work very hard everyday. Its no slouch either... it can even outpull some of the modern machines. Can't be matched for work horse value and long term durability by any other machine, in my opinion. Its made to actually get wet too... and fun to ride if you aren't looking to drag race with it.

If you ever need any parts they are still available used... just gotta scrounge for them to get the good deals. I am restoring an 87 350D right now and having no problems at all finding good parts at relatively cheap prices. Most of the new OEM parts are discontinued (about 99% of them are) but I still buy NOS OEM stuff on the auction site several times every week, as money allows... and I'm having no problem getting everything I need for my project, OEM. Only got a couple more small parts to buy in fact, and I'll be done buying all the necessary parts for my resto and then I'll go buy up some important spares. Got some spares labeled and stacked already...! Lots of good deals still out there and lots of NOS OEMs relatively cheap...

 

[marlinman]

Good to know. In the picture above, you can see traces of an orange frame. It is a trailer I built (pic below) to pull behind my mower and quad(s). Loaded with fresh wet wood the Recon struggles to get it going, but the TRX did just roll out. The 4x4 sure helps backing it uphill to unload too.

The trailer dumps too. It's not complete yet, had too many things going on to get back to it, but it's usable.

 

[marlinman]

Retro

Thanks again for the manual link. Already learning from it. Will go through the diff's and engine oil before getting back on it. Meat to do that before but got sidetracked. Now I have the specs on all of it. I need more paper for my printer though cause at 300 pages it's a big one.

Always print a back up to the computer. I have lost valuable info by not printing it out before.

Also I found suitable syringes on Ebay for reverse bleeding, at a whopping $1.87 each and free shipping. Now I need to make a bleeder cap so it will drain away the excess into a bottle.

 

[retro]

Thanks for sharing all that marlinman! Nice work!

Hang around after your work is done and have some fun with us if you can...!

Edit:
Thanks for reminding me to go for some more printer paper too. Not all of my recent manuals are in print yet... and I can't live without any of them.

 

[hodge5]

You may need to consider new brake lines, which won't be hard to source, if you don't need originals. I just put braided ones on my 300. If the old lines are collapsing internally, it will make it harder to bleed.

 

[shadetree]

I have to say, due to the age of this quad I am leery of using vice grips. Lord knows how hard finding a brake line might be. I think I am going to stick to my back bleeding for that reason. I will post when I get it going.

I have thought of making a false cap even for back bleeding, and that way I don't have to keep siphoning it out of the reservoir to prevent overfilling. I will post that too if I do it. I didn't on the other quad and it was a PITA, especially when I forgot to siphon.

Thanks for the valve tip. That will make it all easier.

One thing I have noticed about this bike over the 98 250 Recon we have. The 250 will run circles around the TRX350, but I assumed it was due to less weight and drivetrain loss. Does this sound reasonable? The TRX does not miss and it will scoot when I push it, but the little Recon just comes out of the hole a lot quicker. I don't race it at all, but it is an observation. It also seems like the TRX is geared lower, since first gear winds out pretty fast.

because the 1986 trx350 fourtrax is not, was not built for speed !. they were built to be a work horse, which, if all running right and stuff ?, THEY DEFF WILL HANDLE ANYTHING YOU TOSS AT THEM !. as for the vise grips ?, as long as you don't clamp really hard down on the line ?, yu'll be fine, been doing it this way for many years, not once have I ruined a brake line.

 

[Goober]

Nice rig there! Do you think your master cylinder might be bleeding back?

 

[marlinman]

I don't THINK so cause this didn't start till the DF wheel bearings overheated. I think it boiled air bubbles into it.

 

[Goober]

Hmm I didn't have problems getting air out but here's what I do:
Velcro band the brake lever in depressed position
Put tight fitting plastic hose over each bleeds nipple--route them upside-down U into a beer bottle
Open a bleed nipple and squeeze--fluid will rise in the hose and you will see any bubbles or discolored fluid
Keep squeezing unless the fluid level in the reservoir gets low then top it off
Fluid will rise to the top of the U then drain into the bottle keeping out any air
Snug the bleed nipple and do the next.
I never worry about recycling or saving fluid, just make sure the bottle you drink from is cold!