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car
6th December 2006, 17:23
That ZXR750H2 I picked up had one other problem: after the ride home, after it had been standing on the drive for a couple of hours, I noticed maybe a dozen drops of oil underneath it.

Investigation showed that it was leaking along the front edge of the cylinder head cover.

I've just pulled the cover (what a bloody tangle that is) and all looks fine inside. Gasket's not perished or torn, but is looking a bit compressed. It's been liquid gasketted in place, except along the front edge (or it was stuck in all the way round and it's come loose at the front). Mating faces look clean, uncracked, unscratched. Of course they might not be entirely flat, hard to tell by eye.

The only odd thing I noticed when pulling the cover was that the front-left-most bolt holding the cover down was torqued way higher than the other seven bolts. Maybe it's twisting when it heats up?

Anyway, it'll be three weeks before I can get a replacement gasket so I'm considering just cleaning it all up with a petrol rag then putting the whole lot back together with some more judiciously applied liquid gasket, making sure to torque all eight bolts up equally.

Sound sane? Anything else I should be checking for?

Disco Dan
6th December 2006, 17:27
sounds like a past dodgy repair to me?

clean the faces off and get a proper gasket, do them all up the same torque and that should sort it...

car
6th December 2006, 17:55
sounds like a past dodgy repair to me?

Oh yeah, but not done with panache, skill and style, like what I'd do it.


clean the faces off and get a proper gasket

Got one going spare?

;)

FilthyLuka
6th December 2006, 18:39
if it turns out ya cover/head is warped but only a tad, you can do a dodgy instead of gettin it plained flat... get two gaskets (shut up), slap em on, liquid gasket or some form of hear resistant resin between the two, plonk the double gasket on, chuck extra 10ft/pounds of tourque on the bolts...

Worked fine on an old jappa four cyclinder and the thing is still runnin 10 years later...

Denden

T.W.R
6th December 2006, 19:54
The rubber gasket should have a rib on the top face that recesses into the tappet cover & there should be small lips on the bottom face that help locate it onto the cylinder head.
Clean both mating surfaces thoroughly, also the half circle cutouts, apply a thin film of sealant to the tappet cover then locate the gasket on the tappet cover. Apply sealant to the cylinder head, locate the rubber half circles in place then fit the tappet cover (remember the cover & gasket are directional = arrow forward).
Fit the tappet cover bolts & rubber seals & tighten evenly (the torque setting is 9.8Nm (87in-lbs)), tightening evenly is more important than the torque setting as the bolts screw into the camshaft bearing caps & not the cylinder head. Start from the inner bolts 1st & work in a rotational pattern to the outer bolts ( inner front right, inner rear left, inner front left, inner rear right, outer rear left, outer front right, outer rear right, & outer front left).

Unless the gasket or the rubber seals on the cover bolts have hardened or deformed they're completely reuseable.Mostly if they do leak its through over tightening & usually around the cam tunnel(for the gasket) and the outer front tappet cover bolts.
The external oil feed pipes either side of the cam tunnel at the front have a tendancy to fracture around the top banjo fitting also, so check them carefully as that can be mistaken for a tappet cover leak.

car
9th December 2006, 18:47
Fit the tappet cover bolts & rubber seals & tighten evenly (the torque setting is 9.8Nm (87in-lbs)), tightening evenly is more important than the torque setting

Thanks, mate, that's done the trick. In the end I had to use to some cheap bog-standard silicone gasket sealant, because it was all I could find to buy here, but it did the trick, and (fingers crossed) a couple of rides and I've not seen even a hint of a leak from the cover.

I'm not sure, however, if I might also have a leak somewhere just forward of the swingarm pivot. It's hard to tell whether it's oil I couldn't clean off with the rag before just making its way out, or what. But I'll keep an eye on it.

Still, one less thing to fret about, eh? Cheers.

The last ZXR750 I had (the 750R, no less) always sounded tappy as hell. A couple of other guys I knew who were running similar vintage ZXR750s reckoned that they all sounded a bit tappy. This one I've just got sounded fine with the fairings on, but with the fairings off it's got a clatter to it.

I'd be interested to hear your opinion on ZXR750 noisiness, whether those tractor sounds are just part of the charm.

McJim
9th December 2006, 20:23
Hey C - reading between the lines here:

a/ You got home safe after your soujourn in Auckers.
b/ You bought the ZXR750H you were drooling over while you were here.

Cool banana - sounds like it wasn't completely mint - hope there's nothing serious popping up that will drain the coffers and hope you're enjoying being back on 2 wheels (it'll certainly be more fun than borrowing the RG150 when you were here!)

All the best.

car
9th December 2006, 20:40
Hey C - reading between the lines here:

a/ You got home safe after your soujourn in Auckers.

Aye. I posted a message wishing your missus a happy birthday, did I not? And Meekie Mouse should have (she better have) PM'd you to tell you that I got at least as far as her house. Sorry, man, I thought you'd know I was back, or I would have dropped you an email.


b/ You bought the ZXR750H you were drooling over while you were here.

Aye, I did, for slightly under the reserve price, due to the aforementioned leak and need of a front disc.


Cool banana - sounds like it wasn't completely mint - hope there's nothing serious popping up that will drain the coffers and hope you're enjoying being back on 2 wheels (it'll certainly be more fun than borrowing the RG150 when you were here!)

Never diss another man's ride. At least not to his face.

;)

It's different fun, exactly as I would have expected it to be. The RG150 was an absolute blast. Those blind twisties had me fretting, but other than that, it's a real no fear kind of ride -- total confidence in the bike, nothing but a good buzz. I'd not push one out of my garage.

The ZXR? Well, even though this one's a way down on power compared to the last one I had, it still demands a little bit of respect, and the weight means it needs some hustling through twisty bits. Fun, but I'm definitely taking it easy for now.

I've just come back up from the garage, after having put all the plastics back on. Still waiting for a pair of front discs and pads, but I reckon I might get an hour in tomorrow morning.

If I'm up your way, our you're down mine, I'll certainly return the favour and you can take her for a thrash. I might not try and keep up, though.