Cause of CCT Leak

[Radioguylogs]

I was getting in a last few licks before I take the bike down for the transmission work this winter.

I put only a few hundred miles on it after rebirth, as I was babying the slipping first gear.

The last time I rode it, it suddenly developed a big oil leak out at the end of the Can Chain Tensioner.

Of course it's the end plug, as well documented in earlier posts.

I was pondering why it went from 'no leak at all' to 'big leak' in just one ride. It leaked a teaspoon while sitting for several days.

I noticed in the earlier posts that sudden slow down causes the conditions most conducive to CCT slippage. I recalled that I did some downshifting during the last ride.

That caused me to wonder if sudden CCT slippage could cause enough pressure to spring a leak in the CCT plug.

The thought makes me want to pull the plug, measure the position of the CCT plunger shaft, readjust the tension, and measure it again- just out of curiosity for the sudden cause of the leak, and of course to monitor the chain tension.

I did reset the tension before I brought the bike back to life...

I had not understood why others in the forum were adamant about auto-CCT until I had the leak and I read about the subject. Auto-CCT may be in my future.

[bikerphil]

You can clean the oil off with solvent and apply RTV in the end until you upgrade to the Auto CCT. If the tensioner had slipped you would probably hear a valve ticking noise. Might want to check the crankcase breather tube for kink/blockage, maybe why it is leaking worse now, JAT

[cajun31]

These CCT

oem units are notorious for dripping oil from somewhere. I cleaned mine resealed the end plug with RTV and also put a new seal on the bolt on the side with washer to seal and the thing still gets the occasional drip. I just think it was a poor design to begin with. I still contend with it though as I am still a bit apprehensive on the ACCT conversion. I am not saying the ACCT is not viable I am just still waiting to see what long term use does or doesn't do to the bikes in terms of added or accelerated cam chain stretch and wear. The original CCT does not cause any of that and although messy at times generally does not cause any other problems. By the way I do have an ACCT I acquired a couple of years ago when the conversion was first discussed. I have just never installed it. I have been adjusting the original CCT ever since I bought my bike new and it is just a standard normal maintenance process for me and only takes about 10 minutes to do. Most of that time spent on getting the cover off the side and rotating the engine a coupe of times to the C mark.

[motoman]

oem units are notorious for dripping oil from somewhere. I cleaned mine resealed the end plug with RTV and also put a new seal on the bolt on the side with washer to seal and the thing still gets the occasional drip. I just think it was a poor design to begin with. I still contend with it though as I am still a bit apprehensive on the ACCT conversion. I am not saying the ACCT is not viable I am just still waiting to see what long term use does or doesn't do to the bikes in terms of added or accelerated cam chain stretch and wear. The original CCT does not cause any of that and although messy at times generally does not cause any other problems. By the way I do have an ACCT I acquired a couple of years ago when the conversion was first discussed. I have just never installed it. I have been adjusting the original CCT ever since I bought my bike new and it is just a standard normal maintenance process for me and only takes about 10 minutes to do. Most of that time spent on getting the cover off the side and rotating the engine a coupe of times to the C mark.

Sounds like just procrastination. Can tell you several LD riders here have way over 80K on the auto-adjsters with no ill affect. One member even inspected the guide assembly where adjuster arm rides against it after some 80K miles. No wear....nil. Your bike WILL be happier with cam timing spot-on ALL the time....it IS noticable.

[cajun31]

Brant

Absolutely! I tried to find the ACCT I bought and for the world of me I can not remember where I put the thing. I was going to prep it for installation. Oh well... it will come to me when I am not even thinking about it. I wanted to find it so I could get it painted black to match the engine. Glad to hear that folks are having success with no additional worries with them.

[James England]

The original CCT does not cause any of that and although messy at times generally does not cause any other problems.

Are you sure that is quite true? The OEM tensioner has been know to cause severe problems in several bikes, especially when the throttle is released after high speed. Every OEM tensioner plunger I've seen has been indented and scored by the lockbolt. It's also very weedy and thin, with about half of its diameter reduced by the flat cutaway for the bolt to press against it and hold it in place. When adjusted, it is quite easy for the plunger to move enough for the lockbolt to move to a previously made indentation. There have been cases of serious engine failure as a result of this.

ACCT's are fitted as standard on more bikes than not. My XJR has one, permanently pushing against the tensioner blade. If one thinks of the strain that a camchain takes just in its normal life, I doubt very much that the tension on it from an ACCT will cause any problems at all. My only concern when fitting my first ACCT was that the plunger does not, unlike the OEM, have a rubber/Viton/whatever block on the end of it. So, there is metal to metal contact on the end of the plunger and the tensioner blade, which only has rubber on the chain side. I was initially bothered that this might cause the tensioner blade to wear but it is permanently oiled and I've not noticed any side effects so far.

Personally, I would feel very uneasy about hammering my bike with the OEM tensioner on. Never mind the regularly happening oil leak from that plastic covered, thin metal, pressed-in bung. Very primitive....

[TopCatGr58]

Hey James,

Well, I will chime in that I had the OEM CCT for the ~50k miles I put on mine before the tranny died. And then another ~20K or so after my rebuild with the big bore kit, and I really thumped on it a lot in those 10 + years after the rebuild, running thru the twisties of the mountains and generous amounts of engine braking from 7k rpm down to 4 and back up again, over and over! It never failed. However, I am the only owner of the bike, and so the lock bolt and nut were never OVER Tightened, so the housing threads were not stripped....which is the main way that these things fail....with the lock bolt threads stressed and partially stripped but folks don't know it, THEN the bolt does NOT hold the plunger shaft securely, and it then allows it to move, and the chain to slacken and cam chain gear teeth to get jumped, get out of time and bend valves.

I have gone to the 30 minute OEM CCT MOD via carriage bolt/nut combo because I wanted to be able to monitor the amount of slack/stretch that my chain was undergoing WITHOUT having to remove the CCT unit to measure and such...which then puts the owner at more risk of chain slack dropping and skipping teeth! My OEM plunger was CLOSE to the wear limit/distance in towards the engine, but not all the way yet, so I know I'm close to the time to change the chain, but not yet. But with the ACCT, folks can't EASILY tell how much stretch the chain has undergone without having to pull the ACCT, as well as the valve cover and such!

T.C.

[jetmechmarty]

Replacing the chain is not particularly difficult. I went in to do the ACCT modification and ended up with a chain in the process.

[cajun31]

I too

http://www.xs11.com/forum/showthread...light=acct+mod

I believe the ACCT is viable with the mod done by Shming.

[James England]

I used Vmax ones on mine. Nice and strong and easy fit

[James England]

However, I am the only owner of the bike, and so the lock bolt and nut were never OVER Tightened

A critical factor, TC. I think most bikes have had a succession of PO's and there's bound to have been someone over enthusiastic with the spanners when tightening that bolt. Like I say, all the ones I've seen were dented. It's a lot of engine to trust to only a few millimetres of thread in alloy and a bolt and locknut......

[James England]

Replacing the chain is not particularly difficult. I went in to do the ACCT modification and ended up with a chain in the process.

did you use a link splitter/riveter on the chain?

[jetmechmarty]

did you use a link splitter/riveter on the chain?

James,

Yes I did. It's an advantage of my geographic location. Another member of this forum brought the tool to a rally. I did the job and mailed it back to him.

The appropriate kit is available from several easy to find sources.

This one is Parts-N-More and is $60. The small pin is delicate and it was broken in the kit I used. I sourced a replacement from Mike's XS. I broke that one, too! I bought another before returning it. My chain came from Z1 Enterprises. It appeared to be a little more robust than the one I removed.

[Radioguylogs]

CCT did not Slip

Just to close the original post.

I was worried my OEM CCT has slipped to cause my CCT oil leak.

I bought a new plug, but I measured the CCT position before I installed it. Then I reset the CCT, and measured it again. No change.

I had wondered why the oil leak happened so suddenly,.. and it was a big leak.

It just happened.

Case closed.

[TomB]

Hey James,

Well, I will chime in that I had the OEM CCT for the ~50k miles I put on mine before the tranny died. And then another ~20K or so after my rebuild with the big bore kit, and I really thumped on it a lot in those 10 + years after the rebuild, running thru the twisties of the mountains and generous amounts of engine braking from 7k rpm down to 4 and back up again, over and over! It never failed. However, I am the only owner of the bike, and so the lock bolt and nut were never OVER Tightened, so the housing threads were not stripped....which is the main way that these things fail....with the lock bolt threads stressed and partially stripped but folks don't know it, THEN the bolt does NOT hold the plunger shaft securely, and it then allows it to move, and the chain to slacken and cam chain gear teeth to get jumped, get out of time and bend valves.

I have gone to the 30 minute OEM CCT MOD via carriage bolt/nut combo because I wanted to be able to monitor the amount of slack/stretch that my chain was undergoing WITHOUT having to remove the CCT unit to measure and such...which then puts the owner at more risk of chain slack dropping and skipping teeth! My OEM plunger was CLOSE to the wear limit/distance in towards the engine, but not all the way yet, so I know I'm close to the time to change the chain, but not yet. But with the ACCT, folks can't EASILY tell how much stretch the chain has undergone without having to pull the ACCT, as well as the valve cover and such!

T.C.

Just reading through this interesting thread gave me few thoughts......

I have the same feelings as TC on the OEM CCT, I havn't gone down the carriage bolt and nut mod yet but may do later. I too like being able to monitor chain wear.

When building drag bike engines based on the GS1150 engine we fit an APE manual CCT, replacing the auto tensioner. These are nearly identical to the mod TC has done, and work great on the drag bike. Also in my past bike spannering days for customers I used to get lots of 1980's Kawasaki auto tensioners that would give LOTS of trouble, and they looked identical to the Yamaha tensioners, maybe why I prefer the manual version.

I'm not sure how any working CCT will affect valve timing, it doesn't work on the drive side of the chain, but in the slack side. (ref. Motomans comment)

James you mention premature wear on the chain and tensioner as it didn't have a rubber damper, I was more concerned with tensioner wear when the auto mod was first looked at, anyone checked that?

Not so much case closed for me, more like jury is still out. I was concerned when folk first came up with the mod, glad my concerns seem unfounded and XS1100s are still running good with the Auto CCT.

http://store.schnitzracing.com/ape-m...gs1100-gs1000/