gasket leaking ...big problem or not?

[Walkabout]

Hi again Auke,
I 've just got the rocker cover off again and am about to check the timing, so I really need to get the right mark - At the crank I now have it lined up on the single mark that I described earlier (but I have not changed the camshaft alignment, yet!) and it makes a difference of about 10-15 degrees in the angle of the two timing marks on the camshaft gearwheel to the cyl head - looking at the cam lobes, that would make quite a difference to when the valves open and close.
AND the bike kicks over very freely now that the rocker cover is off and the spark plug is out; it was "jamming" earlier at about the 2/3 point in the full range of the kickstart movement and it was very difficult to get it to go past this point and on toward the footpeg; in fact most of the time, it would not go past that 2/3 point - bearing in mind all of the earlier advice about the engine must turn over freely by hand before attempting to start it, I am concerned to get this right this time. The way it has been this past day or so, it would not start anyway on the kickstart because there simply was not enough travel in the kick action (& I believe that the decompression lever was set up OK).

Back to the T mark for a moment: are there any more marks on that flywheel that I should be able to see (covered in oil, they are not easy to see anyway)? I ask because my manual is a bit confusing in the section for re-assembling the engine; it talks about (and shows a view of) aligning marks on the crankcase with the camchain driving gearwheel at the bottom of the engine i.e. with the crankcase lefthand cover off.
As I said in my previous post, the "implication" of the adjustment section of the manual is that the single mark on the flywheel is relevant for the valves with the H type mark used for a strobe light. It even shows the H mark just to the left of the single mark i.e. the 10 degrees or so mentioned above.

Apart from that, I have been experimenting with a timber ladder put under the bike and using that as a lever to lift the engine toward the upper frame - I reckon that will work when I eventually get back to that stage!!

Summary: my main concern at present is to get the timing right AND that the bike turns over freely when the engine is back together.

Apologies to one and all for such long postings!! but I have not done this before!!!!!

Not able to progress this tomorrow (another day off!) so loads of time to keep me on the straight and narrow path.

Dave

[aukeboss]

Marks: my bikes have a T mark, if yours does not, you can find the correct one by sticking a long screw driver into the spark plug hole, rotating the crankshaft and feeling TDC. There MUST be a mark, marked T or anything else indicating the TDC. Alternatively, remove your LH cover, then it will be easier to find the correct mark. yes, I know it's more work, but might save a lot of sh*t later.

To find the cause of the difficult kickstarting, suggest as follows:
1. With plug removed and camshaft not installed, try turning -> OK, proceed to 2
2. Install camshaft and valve cover, no plug, crank engine, if OK, proceed to 3.
3. Install plug. Adjust deco mechanism: the lever on the head must have 1 mm of play, with the piston at TDC, valves closed. Make sure taht the deco mechanism indeed works. You see the lever at the head moving when you kickstart? OK -> OK

Auke

[Walkabout]

Just for clarity, the marks look something like this on my TT600R flywheel (I guess the XT is different):-

H l

They are quite close together.
According to the manual, the one on the left is to be used for a strobe light as I described before (and, in detail, it looks a bit like a T written sidewards, underlined with a vertical mark). That is the one I used a few days ago to set the camchain.

The one on the right is for the valve timing according to the adjustment section of my manual AND in there it calls this mark the "T" position; combined with the re-assembly of the engine bit of the manual that has the crankcover references, the manual is a bit ambiguous and can be read in different ways, which is pretty much what I have done up to now.

Anyone else with a TT600 can confirm that I should use the righthand mark of these two choices?

Thanks Auke,
Taking off the LHS cover is an option but it would be quicker and easier to set the timing to the new mark and see what difference that makes. I take your point about doing it in stages; ; last time I put the spark plug in "early" while it was easier, so I don't know what difference that made last time around.

Cheers,

Dave

[aukeboss]

The engine runs counterclockwise seen from the LH side, so it´s logical that first the ignition timing mark(s) pass(es) the ´window´, and then the valve timing mark. I cannot physically check, but think there are two ignition marks: idle and high speed.
I checked a manual for a TT600RE, and this one also speaks of a T mark. Could be that your valve timing mark has not been indicated by the T.

The way to check is to insert the screwdriver into the plug hole, the mark that best corresponds to TDC is the valve timing mark.

Auke

[Walkabout]

Hi again,
I got in a few minutes on the bike tonight and........

I set the timing anew (with the right hand mark) by removing the timing chain tensioner, lifting the chain and moving the gearwheel around so that the timing marks are all correctly aligned (screwdriver indicates TDC as well) and then replacing the tensioner. So far, so good.

Then I tried turning the engine over by hand with the kickstart (which moves freely through its full range now) to check that the engine is freely turning with the rocker cover removed. I noticed that turning the kickstart did not always turn the camshaft which would mean that the timing was "dis-connected" from the engine rotations. i.e. the first time this happened the timing would definitely be out of sync.
I then tried turning the crank with a wrench at the opening in the left hand crankcase cover. Again I noticed that rotating the crankshaft in either direction did not rotate the camshaft, ever. In other words the two are able to move independantly of each other!!

This tells me that the timing chain is not mounted on the driving gear at the bottom OR what else? I can't think of anything else!

While I dismantled the engine I did wonder now and again what system there is to keep the timing chain correctly aligned at the bottom while it is very loose at the top (the manual simply says to tie it out of the way and not to let it drop back into the engine - there is nothing to say that the chain must be kept taut, and it wasn't).

What views on this please?

Dave

ps the timing chain appears to be tight enough on the top gearwheel - no chance of "slipping" for instance.

[mavis cruet]

hello. just been through all this with my 1vj tenere (same leak, same place), and today we came to start it. after a few gentle kicks the kickstart is fairly jammed but you can still turn the crank with the rotor bolt on the left hand side (as used to check the timing). although when you do turn it it moves with a juddering and a whiring kind of noise like if you turn it backwards by mistake. obviously im going to check the timing again tomorrow, but during re-assembly it was turning really sweatly and it was fine whilst i was checking the valves etc, so it has been turned over several times by hand. could this be a completely seperate thing or more likely the timing? im convinced i set it all right and the fact that its been turned over a bit prior is confusing me!


sorry to butt in at this late stage, but its a similar thing so i thought it best not to start a new thread.

any help appreciated.

P.s. i used the timing mark with a T next to it to determine the tdc. was this the right choice? its what i always use for the valve clearences.

p.p.s. when i took the engine appart i removed all the bolts bar the swing arm and the engine tilted forwards to give clearance, i dont know if this is what youre supposed to do for the ttr?

all fingers crossed !!

karl.

[Walkabout]

Hi Karl,
Welcome to the "bust bike" club! I hope the shed load of stuff that has been coming up on here has been of some use to you up to now - if you read my latest post (next to yours in timing) you will see that I have gone backwards tonight.

I am no expert you can tell, but what you describe sounds very, very much like what I am finding!!!!

Thanks for the thoughts about the engine bolts issue: if you only have that one bolt at the swing arm, what stops the whole engine rotating forward too far, unless you kept that one bolt fully tightened up? (I guess that is what you did).

Cheers,

Dave

[Alfow]

I had a similar problem with keeping the chain on the crank on an FZR recently (same ohc principle). I found the best way was to hold the chain between your fingers while turning the crank from the crankcase, try to increase and decrease the taughtness of the chain until it engages with the crank. Once it has, keep the same chain taughtness and turn the crank several times to ensure it is properly located on the gear. Try to keep the chain nice and taught when fitting the cam. Hope that helps.

[Walkabout]

Many thanks Alflow,
That certainly makes sense and is better than my manual, which says nothing useful on this (I've just re-read everything to do with the timing chain).
It's nice to hear that it can be done without stripping the engine again!!

Dave

[mavis cruet]

regarding the bolt on the swing arm. on my 1vj tenere, i remooved all the other engine bolts then the engine tilts forward on this last bolt and rests on the front frame down tube, giving you a touch more clearance above the head.

dont you just hate garages with no lights - ive got to worry till the morning now!!! lets hope tomorrow is full of (pleasant) surprises...

[mavis cruet]

just pulled the engine apart and the timing is all ok. what im feeling when turning the engine over at the crank is the starter motor turning, it doesnt dissengege with the engine. ive no picis in the clymer manual, does anyone know where/how the starter dissengages? ill post this as a seperate thread as well as ive changed the subject...

[*Touring Ted*]

This thread is overly complicated now, i cant make head or tail of whats going on.

Thread hijacking is naughty Too many people on one thread. Maybe new threads should be started ??

Walkabout: You say your camshaft isnt turning when you turn the crank by hand ?

You have probably let the chain slip off the lower gear. Do not try and kick the bike again. I just hope you havnt jammed the chain in the gear or it will shear off the teeth requiring a new crank

You need to grab hold on the cam chain and make sure it doesnt spin on the crank.

[Walkabout]

Well, I have the timing cam in bits again and the timing chain is definitely not aligned with its driving sprocket at the bottom.
I 've been "fishing" around to try to get the timing chain back onto the driving sprocket at the bottom. Looking down the timing chain tunnel with a bright light it is clearly off the sprocket at the front and loose there, but it is a bit tight at the back - could be jammed between the rear chain guide and whatever.

I will carry on doing a bit more "fishing" but it is possible that this is not going to work out. As Auke says, the next thing will be to take off the left hand crank cover, although I have considered stripping down the engine again to get at the timing chain from above (any comments on that approach??!!)

Some questions arise:

1. It is not clear to me what is behind the left hand cover - as ever the manual is a tad vague - will I get directly to the timing chain and its driving sprocket once the cover is off or are there any other things in there to be removed once the cover is off?

2. Do I have to drain the oil to take off the left crankcase cover? (there is an oil pipe from the tank at the top rear of the cover and it is a bit flexible with an amount of flexy hose back to the oil storage tank (so it looks like it can "stretch" a bit)

Bear with me, I've not done this before either!!

While fishing, as described above, the timing chain looks OK and I have turned the crank with the wrench and the sprocket does not appear to be damaged - no teeth missing etc etc. ( it is easily seen with said bright light, just not so easy to reach out and touch!!)

Dave

ps I would really like to get this bike back on the road before the summer is over!

[Walkabout]

............. to my last post, that there is nothing wrong with the timing chain either, not obviously anyway - it turns quite easily over its full length(feeding it through my fingers as the crank is not turning it) so I have looked at all of it and there are no teeth missing, broken or showing any other form of damage - it just will not move across onto the driving sprocket at the back - near the guide in fact. I've tried to use a long-handled screwdriver to move it over but that has not worked.


So, what is behind that left hand cover???

Dave

[*Touring Ted*]

Originally Posted by Walkabout

............. to my last post, that there is nothing wrong with the timing chain either, not obviously anyway - it turns quite easily over its full length(feeding it through my fingers as the crank is not turning it) so I have looked at all of it and there are no teeth missing, broken or showing any other form of damage - it just will not move across onto the driving sprocket at the back - near the guide in fact. I've tried to use a long-handled screwdriver to move it over but that has not worked.


So, what is behind that left hand cover???

Dave

Under the left cover is the alternator / generator / rotor or whatever you want to call it.

Its a bloody nightmare to remove but i think (if i can remember correctly) that the chain gear is behind the rotor.

Take the cover off, its a simple and yes, you need to drain the oil as its wet in there.

With just the cover off you might be able to get the chain back on without removing the rotor.

If you have to get the rotor off then then you need a special tool which is £180 from yamaha or you can make one yourself.

I hope you dont need to remove the rotor, its a BITCH job without the yamaha tool.