1990 Yamaha Big Bear 350 4X4 Timing Chain

[WIJBIRD]

Looking for a guru to help me get the top end back together. I'm stumped!! There seems to be an issue with the removable chain guide on the left hand side. In its current position (which is probably incorrect) there's not enough clearance to get the chain on the sprocket and be able to line up the timing. Does the guide rest on the side or is it supposed to be in the notch underneath? I have a manual, but it doesn't show the correct positioning on that guide. I tried to fit it in the notch, but then the cylinder head doesn't seem to seat properly. Let me know if you need pictures. Any help (and pictures) you able to provide will be greatly appreciated.

Thanks in advance!!

Jay in WI

[Frank Angerano]

Hey @WIJBIRD, when you took everything apart did you remove the chain tensioner ? 

[WIJBIRD]

Yes. That's not the issue, but thanks for your reply.

[Frank Angerano]

Post some pics. 

[WIJBIRD]

OK. I'll post some pictures after work tonight. Thanks for replying.

Jay

[Tahj]

1990 Yamaha Big Bear 350 4X4 Timing Chain2.doc

[Tahj]

Guess that didn't work  

can some one open it or tell me how to post it properly

[WIJBIRD]

I was able to open the exploded view, but I already had that diagram.

Thanks for replying though.

Jay

[MarkinAR]

If it's like the 93 Kodiak I had apart recently, there is a valley at the bottom of the front (not adjusting) the timing chain guide goes in to.  The top of that adjuster just kind of "sticks up" into the rocker cover.  It seems that I got the front guide in a bind and noticed that it touched the chain so it sounds like you've done that also.  Just have to get it seated right, may have to lift and lower the head a dozen times and then it just magically sits down cleanly.

[WIJBIRD]

Here are two pictures. If you look at the lower left corner of the sprocket (I know that circles don't have corners), you'll see the top of the black chain guide. Is it suppose to tuck into that little "pocket" in the cylinder head? I tried that once, but then the cylinder head wouldn't seat. What do you all think?

Thanks!

[MarkinAR]

Looks fairly normal to me. As long as the bottom sits in its groove the top is just suspended. The kodiak I had apart you could flick the forward guide forward and backward a bit with the chain tensioner out. 

[WIJBIRD]

So, should it go into that pocket just  underneath/behind it?

[WIJBIRD]

I got it! It did go in that pocket in the cylinder head. MarkinAR commented that you just need to keep lifting the cylinder head up and down until that guide sits in the correct position and then everything fits together. Wow, what a relief!!

Thanks to everyone for their input,

Jay

[MarkinAR]

Glad you got it, I knew you would. Once everything is correct it almost puts itself together. Now just triple check timing. It can be tricky if the chain isn't new. 

[Frank Angerano]

Nice work brother! Get that puppy all back together and break it in nice and easy. 
Ride safe.   

@MarkinAR good stuff my friend!  Well done.