Project The Dying FZ

The timing is the same as the FZR, I checked that for sure when we started. Reason I know is that (1) cams and cam caps are the same (2) CCT is the same (3) Cam chain is the same (4) the timing marks on the cams/caps line up the same. The only difference is the T mark on the magneto, it is more similar to my 400 where it lines up with the engine case split rather than a dedicated position on the case. I checked that, the piston position and cam cap/cam alignment when I originally put it at TDC. I'm starting to wonder if I can transfer my spare FZR head onto it... that would be an interesting experiment but would probably have to put carbies on it as well...

Yes normally I wouldn't reuse a head gasket but I'm trying not to invest in this bike. I am now a bit concerned that if I am able to get one and put it on I'm not sure it's going to fix the issue.

The issue is now it is still binding without any spark plugs in it, I am turning it by hand slowly and it gets to the point I just can't turn it any further and it stops dead. Don't want to bend any valves so I'm not going to force it but I think that's enough for me to pull the head off again. Hopefully none of this has bent any of the valves.

I'm not sure what to look for to see "how much meat" is left but that is something I'll look into. I have a service manual on the way but don't know when it will get here from japan either.

Hmm I like the thought about another base gasket.....

 

Yeh I hear you. I guess it was worth a shot, I think it will seal ok but the clearances under tension are obviously causing an issue. I'll try to get a head gasket and see what is going on but either way head has to come off again now as I need to check the valves.

 

Well I had a chat to the guy who was doing some head work on the 400 and he said it is strange indeed. He suggested the same as what has been said about putting in another base gasket to raise the bore a little to gain some clearance if I'm sure all the timing is done correctly. He said reusing a head gasket is typically not recommended but he has done it for years on dirt bikes etc where it doesn't matter as much, he just uses hylomar spray in those cases. The thing that confused him is how it bent the spark plug but it's possible the thread is a little deeper in the retapped holes than the other two which could explain it. Maybe as someone suggested I need another washer on the plugs. He didn't think the re-used head gasket should have much affect on the clearances.

The issue is now I can't rotate the crank with the cams in as you get about 90 degrees from #1 TDC and it stops dead. Something is not working properly. Without the cams in it rotates freely so it's something to do with the valves. Will pull it off and have a look when I get some more time.

 

Yeh they're marked "E" and "I" so it's easy not to confuse them, i'm careful with that sort of thing. All the buckets went back where they were supposed to go as well.

 

Are you sure....?

The FZR has the flared sections of the cam on the opposite side to the T mark on the flywheel (where the dots line up). Ie the flywheel is on the RHS (sitting on the bike) but the timing marks are on the LHS (sitting on the bike). Yes that photo above is before I disassembled it but it coincides with the FZR...

 

Ok so I think I had a little win, I should have checked this again and I feel a bit stupid for not doing this earlier (lesson: always, always check never assume... I should know that as an engineer).

I stuck a screwdriver in #1 and lo and behold at what I thought was TDC it was at BDC, meaning I was 180 degrees out. When #1 is at TDC the T mark lines up with the front split in the engine casing as opposed to the rear.

I reckon I'll put it back together now and see how it goes... hopefully I haven't done some valve damage by turning it over by hand but we'll see.

 

Ok so in short - now successful. I can turn the whole engine around repeatedly with no binding so I think we're good.

@my67xr there's no markings around that area I double checked again. The only legible marks are the splits in the engine casing which line up with TDC #1 (on the front of the engine). On my FZR400 TDC #1 is on the casing split to the rear of the engine (closest to rider). I confirmed all that with what the screwdriver was doing to coincide with #1 piston movement.

You are right though, it doesn't explain what was going on with the plugs but given it was from a retapped thread I might have just tightened it in a bit too deeply. I'll just nick another one in (yes I'm using CR8E's) gently and see if the motor turns over OK now, I'll pull them out again to double check.

@ruckusman yes looks the same. You can see the dots on the flared section of the cams to the RHS of the picture, which is actually the LHS of the engine when sitting on the bike. That coincides with what I have. I suspect on that engine the magneto with the T mark will be to the left of the picture, which is the RHS when sitting on the bike... again coinciding with what I have.

The other thing I noticed is that all the camshaft covers have those little dots, but if you look at I2 and E2 (left hand cam caps in the picture above) the dot is right next to the chain. I had them the wrong way round and the dots were to the outside of the engine which would have meant that contributed to the difficulty I had in turning the engine over (as they would be worn differently to how I had clamped them down).