The best gasket goo?

[David Morris]

Hi there,

The winter beckons, and after lots of expert advice and help, for which I have been most grateful, I am now ready to tackle the replacement of the rear timing cover gasket on our Javelin. (See the oil leaks thread earlier) Hopefully, this will at least slow down the oil leaks, which at present are running at about a pint/75 miles! At the same time, I intend to fit the spin-on oil filter conversion.

However, before getting 'spannering', I would appreciate some sage advice on the best gasket cement to use on this gasket. Advice has been varied, from superglue to blue hylomar. I have used green hylomar in the past, but am not sure if this is still available? As you really don't want to do this job too often, to save added wear on the two vunerable vertical threads, what do people recommend as the best goo to use? Are there any magic methods of fitting?

By the way, I have noticed that our Javelin has the single horizontal stud at the front, above the oil filler tube, replaced with a bolt, which should, I hope, allow the rear timing cover to be placed vertically, instead of having to slide it in from the back. I have seen others converted like this as well, was it a factory mod? Perhaps this will mean that the two tappit covers can be left in place?

Many thanks,

David

[Drummond Black]

Dave This area was aired a few months ago and I added my pennyworth.

I cannot remember the last time I had an oil leak from the rear timing gasket area. The method of assembly I use is as follows. The standard Jowett gasket is too flexible for this joint area. I make one from 1/16 inch thick Hallite. This is a gasket material used in the compressed air and petro chemical industries. Use a stardard Jowett gasket as a template but punch the holes first before cutting the profile. 1/16 in thich is the right thickness to allow the holes to line up over the angle of the crankcase.

The fixing bolt holes can be improved as follows :- drill and tap the two fixing holes ( already tapped ) to 1.375 in deep..THIS IS THE MAXIMUM SAFE DEPTH TO AVOID DRILLING INTO THE OPEN CRANKCASE,, and tap 5/16 BSF to full depth. Change the bolts to 5/16 BSF Allen Cap Screws and use a Plain washer with each. Use Allen cap set screws and obtain the lengths as follows. N/side is 2 ins long and the o/side is 1 1/2 ins long.
And on assembly I use Blue Halomar. Remember to fit the centre felt soaked in Halomar. If assembled correctly your oil leak will be a thing of the past

Drummond

[Forumadmin]

Remember, do not tighten the horizontal bolt more than a pinch as it may pull the housing over. I align all three bolts finger tight before torquing down the vertical bolts in stages. Personally, I think the O ring solution is probably the best; although I have yet to try it.