Fork Oil Seal Leak

[Yamazer-92]

Hi guys, I bought my 2001 FZS 600 back in June and first would like to say what awesome bike's they are (although im sure you already knew that)!
 
Anyway I recently noticed that the left fork oil seal is leaking and was wondering how hard they are to replace, plus whether or not I need to replace the dust seals as well as the fork seals and oil or can I get away with leaving the dust seals as they look to be in good condition.
 
This is my first post and this is the first forum I have ever joined, after reading alot of other peoples posts etc I have seen how helpful you guys are and how interesting alot of other peoples posts can be. Any help would be greatly appreciated thanks! 

[His Dudeness]

its handy enough to do. there's a good how to guide on the old site. http://fazerowners.yuku.com/topic/23188/HOWTO-Forks-Seals-Bushes-and-Oil you can get away with just seals but the seals usually fail because crap has got down past the dust seal and into the fork seal but its up to you. i would say definitely go for genuine seals though. there's no special tools needed but you have to have a bench vice to hold the fork.

[Yamazer-92]

Awesome thanks very much, that is exactly the sort of guide I was looking for. I just recieved the Haynes Manual for the bike today which does reccomend replacing the dust seals too but I wasnt sure if it was really necessary if they were in good nick. I got the seals from the wemoto website and they arrived earlier in the week, was hoping to start working on the forks tomorrow but think I will probably order the dust seals and retaining clips too. The fork seals are made by Athena, im guessing that isn't the genuine Yamaha one's? Would you suggest returning them if not?

[His Dudeness]

its up to you. they'll probably do the job just fine. lots of people use after market seals with no problems at all. its just that you know the genuine ones will be good quality and will work whereas with after market ones the quality can vary. maybe stick up a pic of your dust seals and someone will tell you if you can get away without replacing them.

[markbubble]

just to add to an excelent write up if the bottom 'drain' bolt wont undo due to inside spinning if you have access to a windy gun they undo them mega easy so saves pushing a broom handle or similar down the tube!

[Yamazer-92]

Okay cool, I think I will probably chance it seeing as theyre from the wemoto website, havent ever had a problem with them before personally plus they are a little bit cheaper than the Yamaha ones which is handy being a student. Here's a pic of my dust seals on the bike, they are in the same condition all the way around just took a pic of both sides to give an idea. I cleaned the left side but it is definitely leaking a fair bit just doesnt look like it in the pic. Also mark I dont have a gun unfortunately, but do have a few brooms knocking about.

[markbubble]

no probs try the broom,luckly i have a friendly garage who let me go and borrow said tools if needed in exchange for te odd beer! let us know how you get on,good luck and have fun

[Yamazer-92]

Hope the pics are clear enough, what's the opinion on the dust seals then do you think they are good enough to clean up and be re-used?

[markbubble]

hard to tell from pics but look pretty good to me ,

[Yamazer-92]

Right well I'll chance it and use them too then, my dad is much more experinced than me and he said they looked fine. There's no obvious rips or tears in either of them and theyre both nice and tight still. Just means I can do it tomorrow when it's dry rather than waiting another however long for the new dust seals to arrive. Thanks for all the help again 

[His Dudeness]

yeah they look fine. not cracked or dried out.

[Yamazer-92]

Hi again guys, just an update on this post, we managed to do most of the work ourselves bar getting out the nuts holding everything in at the bottom with the broom technique so decided to accept defeat before breaking anything and took them to a local garage to remove and replace the seals and oil. Only cost £15 so can't complain, he did mention bushes would need replacing soonish. However he also mentioned the left side (the leaky side) seal didn't fit as tightly as he would've liked. Anyway after refitting them to the bike, annoyingly a few weeks later now I have noticed that it is still leaking... I noticed small amounts each day since the work but thought it may just be residue from when he fitted the seals to make them easier to fit, but due to rain past few days havent cleaned the bike and looked today and there was a pretty substantial amount.


I asked a mechanic friend what he thought and he said that the stanchion could be damaged / worn and isn't making a tight enough seal or is damaging the new seal to allow fork oil through and probably needs replacing  . What do you guys think, any experience with this problem? If it does need replacing, any tips on where to get a decent second hand one and would I need to replace both? Cheers

[unfazed]

Why would you replace a non leaking seal. If it ain't broken don't fix it.
Were the seals you fitted genuine yamaha ones? I have found that the genuine Yamaha ones seem to work best and I personally would always replace the dust seal when replacing the fork seal.

[His Dudeness]

Why would you replace a non leaking seal. If it ain't broken don't fix it.
Were the seals you fitted genuine yamaha ones? I have found that the genuine Yamaha ones seem to work best and I personally would always replace the dust seal when replacing the fork seal.

i think do the two of them. sure if the first one failed the second one would be on its way out. plus you'd have one fork with brand new oil and one with old stuff. another thing you couldn't guarantee the volume of the oil in the fork you didn't do. also while you have the bike held up and everything off to get the first one out its a lot quicker to get the second one out

yamzer it could be that the aftermarket seal was a poor fit or it could be how the guy fitted the seals or it could be that the fork itself is damaged

[DryRob]

Markbubble's selling a load of parts from an FZS (http://foc-u.co.uk/index.php/topic,5190.0.html) and he might have a full spare fork assembly, try the sale/wanted section, ebay or local breakers but get the full fork rather than mixing and matching tubes and lowers.

It could be the worn bush isn't holding the tube properly, effecting the seal, so needs replacing.

As a side I was goin to go down the cheap seals route when I did them but remembered the motto "buy cheap, buy twice" so got Yamaha seals and didn't have a problem. I've got aftermarkets on my brakes though cos I couldn't get genuine parts in time for the MOT.

[Yamazer-92]

Hi unfazed, not sure what you mean about "if it aint broke dont fix it" because as I said at the start of the thread, the old one was leaking and now after replacement the new one is too still so seems quite broken to me. The seals wern't genuine yamaha ones though, I wasn't sure where to get them and didn't even consider it when I bought the seals from the wemoto website before I started this thread, an experience I will now learn from. To be honest though, the right side is not leaking at all so I don't think the seals are poor I think there is another issue which needs to be determined.


His dudeness yeah I think replacing both is the sensible option but the bike has only done 21,000 miles and the forks don't look to be damaged or corroded unless something is happening below the seal? Surely buying a whole new set of forks is quite a big (also expensive) decision when realistically couldn't I just replace the stanchion on the left, replace the bushes/seals and dust seals in both with genuine Yamaha ones this time and then stick in some new fork oil in both (15w as I used 10w recently and doesnt feel quite as firm).


DryRob okay cheers I will message him and see what he says but I don't want to rush into anything and have to spend loads and loads, for the moment its quite a small leak and the next MOT is due next June. What you say about the bushes is interesting considering the mechanic did say the bushes are worn. Also interesting, how come it wouldn't be advised to mix tubes and lowers as I don't really have a lot of experience with forks? Would it be because of different rates of wear? Thanks again for the tips everyone

[unfazed]

I was answering the question about the need to replace both seals if only one is leaking. If it isn't leaking it leave it alone. Fork seals usually leak for a reason. Impact, pitting fork legs, stone chipped fork legs or seal inners rusted are the usual reasons. I am still on my first day seals after 73000miles, certainly at your low mileage you should not have seal problems.
Is there any sign of impact damage anywhere on the bike. I was on bike run some years ago and the bike behind me went down on gravel in a corner and when he rode it home one for seal started to leak. When we stripped we found the seal on the side it fell on was slightly deformed yet the other was perfect.
How soon after the replacement did the seal leak??? If it was immediate then it is one of two things the seal has the incorrect inner diameter of the seal was put on dry over a pitted section of the fork leg which damaged the inner seal lip. If it was after a 50 or more miles then it is most likely a problem with the fork leg. I would suggest that you inspect the fork leg closely to ensure there is no surface damage. If necessary remove both legs clean them with something non abrasive (I always use a soft cloth soaked in WD40) and compare them. check for pitting in the area between the yolks where the yolks clamp and pitting & stone damage between the dust cap and the yolk. If all is ok replace the leaking seal and dust cap with genuine yamaha  ones preferrably(this will rule out dodgy seals).
Good Luck

[limax2]

I completely agree with  what "unfazed" says above. (I'm a creep I know). I would be very surprised if the bushes are worn at 21k miles. I would follow the above advice and have a good inspection before spending big bucks on replacing forks.

[His Dudeness]

they're just seals they fail for plenty of reasons at all sort of mileage. sometimes one goes, sometimes both go. doing one at a time doesn't make sense to me. if you had a sticking piston in a brake caliper you'd never replace the one seal on the sticking piston you'd do the set

[Yamazer-92]

Hi unfazed, ah right I understand what you meant now, I was always under the impression that to keep it even you would just replace both at once though, they arrive as a pair etc and cant remember but I think the Haynes suggests it. Interestingly with your point about impact damage though, the bike is in brilliant condition except for a fairly large crack and hole in the front fairing on the left side above the leaky fork which is quite annoying as everything else looks great, doesn't look like its been down the road at any point. I was actually considering street-fightering the bike because of it but to be honest I like the square eye fairing and clocks and didn't like how the clocks are bodge mounted on others I have seen plus didn't fancy spending loads on a replacement naff digital one. Do you think that could be part of the issue? I can take some photos of the forks and fairing damage if you like so you can have a look, I can remove them from the bike and clean them up although I do quite often like you say clean them with wd-40 and a cloth when I clean the rest of the bike. To be honest, as soon as I got the forks back and refitted them I went for a ride about 50 miles or so and straight away when I got home I had a look and saw some oil residue on the fork on the left which was really annoying. When I fitted the forks, I did give them a pretty good pump to make sure it all felt good and there was no leaking immediately at that point but I guess me pushing on them is a lot less force than having to break from 60-70mph even though I was being as rough as I felt would be necessary to see any leaks. When we took the forks apart like I say we didnt get the lowers away from the tubes so didn't get to see how the bottom of the tubes looked, but they do look good above the seal with no real bad corrosion that I can see. 

[darrsi]

Personally, i'd keep the good seal, and replace the whole bike around it......... 

[unfazed]

One question. Is it actuallt leaking or just residue from oil from the fitting of the seal? Lift the dust seal and wipe it clean inside and over the top of the seal, re fit the dust seal and take it for a spin and check it again.
You should always replace the oil in both fork legs not necessarily the fork seals and fork dust seals. Replace it with 10w oil and ensure you have an air gap of 121mm (4.75inches) or 132mm (5.2 inches) in the models with fork adjusters, that air gap is more important than many think. The air gap is checked after filling the fork leg with oil and before replacing the springs and spacers with the fork leg fully compressed standing upright. The distance the oil is from the top of the fork leg should be 121mm.   More than 121mm will make the forks feel softer and less than121mm will make them feel harder. I usually fill the fork a bit more than is needed and then using a syringe with a tube at the end cut to the length I require and resting it on the top of the fork leg suck out the excess oil. Repeat the process for the second leg. Then replace the springs spacers and fork cap.
A word of advice loosen the top clamp bolt before loosening the fork cap and tighten the fork cap before tightening the top clamp bolt.
In answer to His dudeness, I do not think it is a very good comparsion you can still ride and stop with a leaking fork seal. Why would yamaha supply seals indivudally if you had to replace the set. You do not have to replace all the brake seals but when overhauling the brakes you are stripping out all the pistons and seals and it is advisable to replace them all for safety. Yet Yamaha suppy single  brake seal and brake dust seal in kit form not the whole set for the caliper.
Nice one Darrsi never thought of that 

[His Dudeness]

One question. Is it actuallt leaking or just residue from oil from the fitting of the seal? Lift the dust seal and wipe it clean inside and over the top of the seal, re fit the dust seal and take it for a spin and check it again.
You should always replace the oil in both fork legs not necessarily the fork seals and fork dust seals. Replace it with 10w oil and ensure you have an air gap of 121mm (4.75inches) or 132mm (5.2 inches) in the models with fork adjusters, that air gap is more important than many think. The air gap is checked after filling the fork leg with oil and before replacing the springs and spacers with the fork leg fully compressed standing upright. The distance the oil is from the top of the fork leg should be 121mm.   More than 121mm will make the forks feel softer and less than121mm will make them feel harder. I usually fill the fork a bit more than is needed and then using a syringe with a tube at the end cut to the length I require and resting it on the top of the fork leg suck out the excess oil. Repeat the process for the second leg. Then replace the springs spacers and fork cap.
A word of advice loosen the top clamp bolt before loosening the fork cap and tighten the fork cap before tightening the top clamp bolt.
In answer to His dudeness, I do not think it is a very good comparsion you can still ride and stop with a leaking fork seal. Why would yamaha supply seals indivudally if you had to replace the set. You do not have to replace all the brake seals but when overhauling the brakes you are stripping out all the pistons and seals and it is advisable to replace them all for safety. Yet Yamaha suppy single  brake seal and brake dust seal in kit form not the whole set for the caliper.
Nice one Darrsi never thought of that 

they also supply single clutch plates, springs etc etc don't think that indicates anything other than it's all about the dolla baby! you could buy one spark plug if you want. doesn't mean its right. i'd replace the two seals you'd do one. thats ok. you have to embrace difference thats what make the world go round 

[DryRob]

DryRob okay cheers I will message him and see what he says but I don't want to rush into anything and have to spend loads and loads, for the moment its quite a small leak and the next MOT is due next June. What you say about the bushes is interesting considering the mechanic did say the bushes are worn. Also interesting, how come it wouldn't be advised to mix tubes and lowers as I don't really have a lot of experience with forks? Would it be because of different rates of wear? Thanks again for the tips everyone

To be honest I was just guessing that a damaged bush could be allowing the inner to wobble and compromise the seal, I'm not a mechanic and probably wouldn't have suggested the bush if you'd not mentioned it and gone with a pitted/damaged inner. The only reason I said to not mix uppers/lowers is I think I read it in pointer to null's guide not to mix components between forks, maybe that's overcautious but as a fork comes as a set each part will bed into the other differently depending on the fork.

I'd like to know for future reference if I'm talking shit though.

[unfazed]

DryRob, Certainly a possibility but that kind of wear at 21K would only be the result of an impact. If there was wear you would see score marks on the bush or the slider or both. You are correct in not mixing parts , it is as much common sense as being over cautious as no two parts wear the same.
His dudeness :way to philosophical for me