Fat Gasgest

V

Vince

Hero member
Does anyone make or own a thicker rocker box gasket, mine seems to be not thick enough to not leak easily.Are they thinner than in the past?
 
very often a leaking cam box can be caused by a stud sitting too high and bottoming under the cam cover preventing pressure on the rubber gasket. Usually the 8mm cam bearing studs (six off) are too blame rather than one of the 12 off 9mm cylinder head studs. Those 8mm  studs are tapped directly into the head and the head can be very soft resulting in "pulling" of any of them, this is exasperated if the head has had replacement valve seats fitted and has been heated inappropriately with the temper of the alloy lost. It can also be caused by ham fisted tightening of the studs or using a torque wrench that has a scale far too high. If the studs for the centre bearings are pulled/pulling, then its a head off (plus engine out IMHO) to repair, but if it is the left or right ones, an in situ repair is possible but tricky.

I have seen Ricardo Oro in his workshop in Breganze many years ago with a shaped piece of leather, that fits tightly over the cam block and covers everything, then using a bastard file to lower the top of the stud a tad to gain clearance, not recommended, but this was TOG in 2000 after a certain place (shop) that does cylinder head work had softened the fuck out of the head, (and cracked 2 of the 3 skulls)  it was later scrapped but it did get me home, 1600 KM later.

CLEM
 
Vince,

Check the height of your cam bearing blocks.  With the cover fitted without the gasket, there should be a gap of about 0.5mm between head surface and cover.  If your bearings are too tall, the gasket will not be sufficiently compressed for a good seal.  If gasket thickness is correct, the cover can be tightened hard to the cam bearings, the gasket providing any "springyness" to seal properly.

The groove for the gasket should also be clean, I find a lot of crap in there, causing leaks.  I also find loads of silicone sealant in there to keep the gasket in place, and in futile attempts to seal the cam cover.  A thin line of rubber compound adhesive is enough to keep a new gasket in place when fitting the cover.

Gasket should be replaced now and then, they don't last forever...

piet
 
Funny boys, there is virtually no gap between the cam cover and the head that can be seen at the moment. The gap the Gasket fits in was cleared before fitting. Its not that old. Will check this out, thanks for the clues.
 
Have seen 1.8 and 1.2mm thick aftermarket cam cover gaskets. Would guess the original would be at least 1.8mm or thicker.
 
Reggie3cl said:
And then stays for dinner..?
Click to expand...
You mean this bloke............here is the last known photo of him


fredphoto.jpg
 
Hooksey will be in touch for one of Phils hard ones, so I had a fiddle. Rocker box bolts were finger tight, exhaust studs were finger tight, hose clamps on the oil cooler hoses were finger tight. Expect that would add up to a nice black coat of oil down the engine front.Pulled the Icon shocks off, yep one is leaking and lucky me. I also have a left fork leak, not from the seal, from the bottom drain bolt.Must need a new copper washer. Might need a degrease after that.
 
Isn't that referred to as a Nut and Bolt. Seems my bike needs it after a few expressway runs, it does get buzzy over 4500. I don't usually do a nip up till I see it needs one.
 
just measured my gaskets - reading blurred but readable - vernier pushed in tight too!! - Selling these @ ?16.50 inc Uk delivery if anyone needs them - regards - Phil
 

Attachments

  • cb gask.JPG
    cb gask.JPG
    197.5 KB · Views: 34
You must log in or register to reply here.
Back
Top