Front fork oil seals???

OK I need to replace the seals in both forks. So how big a job is this and what do I need to replace? What tool/s do I need for the job? I have NEVER done this before and I just can't find what I'm looking for with the search function. Its an 83 XJ750K. This is the LAST thing I need to do before I get a safety inspection done on this bike.

 

How bad are they leaking - and for how long? Before I'd spend ( again) all the money I spent on the fork seals. I'd try the 35 mm film trick to clean out the seals. If you don't know how to do it - just google ' 35mm film fork seal trick' . Basically, it cleans the crud out of your seal and you're good to go. I did it on my goldwing and it works.

 

If you have the Original Seals it could get tricky.

The FIRST thing you should do is:
Get a WorkShop Manual.

Get familiar with what you need to do and the Tools you will need.
Use the opportunity to Overhaul your Front Forks.

You will need:
New Seals and Dust Covers
New Circlips
New Fork Springs
Quality Fork Oil

You have to Undo and Remove what needs to be Removed and set-aside to Pull the Forks.
One at a time is OK.

You have to Remove a Fork from the Bike.
Remove the Clip and Retaining Device
Remove the Fork Spring
Remove the Damper ... down-inside.
(It unbolts from the bottom of the Outer Tube. You need a Tool to reach-down in and hold the Damper while the Bottom Bolt is undone.)

Pull the Damper and Springs
Remove the Inner Fork Tube
Remove the Old Seal
Clean
Replace Nylon Slider
Clean
Fit the New Seal

Put the one side back-together, ...
Measure and Fill with Oil
Button it up
Reinstall

Do other side.

 

Both forks leak.
So Rickinduncan what you are saying is that there could be dirt under the seals causing them to leak. You use the 35 mm film to clean out the dirt from under the seals. This then stops the leaking. Could be worth looking into.
RickCoMatic What kind of tool do I need to get at the damper? I'm not afraid to do the work as long as I can get the tools to do it. The bike has been well maintained by the PO. So far it looks like parts need regular maintenance and replacing have been done. So I am hoping this is the case with the front forks.

 

The "special tool" for the damper rod is probably in your toolbox already.

Find a spark plug socket with a 19mm (3/4") hex cast onto the outside bottom of it, mine is on a 5/8" plug socket.

Flip it over, and plug every 3/8" drive extension in your toolbox into it. You'll now have a big long 19mm "allen wrench" that will fit in the hex in the top of the damper rods.

Or you can use a long threaded rod with a couple of 19mm nuts welded on it, or whatever; I like the inverted spark plug socket solution because when you're done it all disappears back onto the tool box.

 

Thanks for the tip Bigfit52. I'll pull the forks apart and see what I need to do then. :roll:
The tail light is not here yet, not surprised. Good old Canada customs/mail delivery!! Hope it comes before Wednesday, our letter carriers are supposed to go out on strike then :evil: .

 

You gotta be kidding me. That's one full week today. I've sent stuff to Wiz in Australia and Igor in Chile and had it get there in less than a week. Gotta be on your side of the border.

 

Something else you may need is a fork seal driver tool. A "real" tool is expensive. There are several threads that discuss how you can use the right size PVC pipe to do the same function for practically nothing. Worked beautifully for me. You just need to get the right diameter and make sure any cut ends are smoothly sanded.

 

HAHAH Fitz, one week is nothing, it's quite regular to see stuff take a month to get from the US to our doors.

 

Ya Fitz thats life in Canada! :twisted: The more we pay our civil servants the worse it gets. I'm just hoping to luck out and it comes early, before the postal strike. I just hope they settle it with out the strike.

Artie(RT) I'll look for the thread on the seal driving tool. Thanks for the heads up about it.

 

I have had my bike for many years now and the last time I had to replace those seals I decided to prevent them from needing it again. I got some rubber fork covers made for an off road bike and put them on my forks when re=assembling. It has been many years now and no more leaks from bugs or dirt etc.....I dont care that it looks a bit strange, I do like the fact I may never have to do the job again......

 

Hi
Does anyone know how much oil I need to add once I change the seals? I have a 82 Yamaha Maxim 750cc. Thanks

 

Update on the fork seal installation. It took this long to get all the parts. I now have the forks all together. I have not installed them as I need to fill with oil. Which comes to the question of oil to use. The service manual from Yamaha says to use either fork oil OR 10W30 oil. What would the difference be in performance? Cost wise $15 a liter for fork oil $4 for 10W30 a liter.

 

10W30 is formulated to be motor oil, so it's effectively 10W oil as you'll never get the forks hot enough for the other spec to apply.

Fork oil, on the other hand, is formulated to withstand all of the operating parameters of forks, rather than to lube a motor. Plus it comes in 15W, my preferred weight.

Considering how little you'll need (one bottle will easily do both forks) and how rarely you'll change it (probably every other season, like Moi) I would go with fork oil.

That being said, motor oil isn't going to hurt anything.

 

Another alternative, ...

Hydraulic Jack Oil.

http://www.amazon.com/Permatex-80051-B- ... B001EZL9PA

 

OK I went to the local Yummieha dealer, local is anything less then an hours drive, and picked up some FORK OIL. I replaced the oil and pumped the shocks up and down a few times NO oil on inner tubes!!!! Great!!!
Put them back on the bike, now she don't look so sad. Now how do I get three pounds of air into them???
None of the bicycle pumps I have seen have gauges that will read that low!!

 

Commercial lawn mower shops have a stick gauge that reads 1 - 20

TIP : load a portable air tank adjusted to your goal air pressure, then air up your shocks.

 

We do have a portable tank here. I'll see if I can get it loaded up with just the right amount of air.

 

Question for Fitz and others---if you replace your fork oil every 2 riding seasons (are you counting years? It says you're in MI like me; I'd say maybe we get 1/2 a riding season per year, so that's 4 years...) do you also replace the oil seals and dust covers at that time?

I'm wondering because I replaced mine about 5 years ago and they're leaking again. Either I only replace the dust seals and not the oil seals (possible because I didn't know what I was doing) or I replaced both and they need to be done again. I would probably get the whole basic rebuild kit from Chacal this time and make sure that it's all done exactly right.

Also, I assume if oil is actually coming up it probably means the oil seals are compromised and the things need to be pulled apart. Is there any other possibility? This began to happen when I wasn't even really riding the bike, it was just sitting and as the weather got warmer, oil started spewing upward from inside the bottom tubes.

Thoughts?

 

I do it every other spring as part of my "wake up" service. I replace the dust covers when I replace the fork seals; and I only replace those when they start leaking, not based on a "maintenance interval."

If oil is getting out of the forks, then the OIL seals need to be replaced, yes. If you continue to have leaky forks after the oil seals have been replaced, it's likely you have some pitting in the fork tubes that's damaging the new seals.

Leaky seals are leaky seals; it's pretty straightforward.