Skip to main content
English French German Italian Spanish

oil bath seal caulk

can anyone tell me of an alternative to silicone when fitting the rubber seal on my oil bath, its very difficult to break the seal when dismantling, and even harder to clean up the parts befor reasembling .

Permalink

Terrence, do a search here on the forums, a lot has been written re this seal palava. There is a modern polyethylene, oil resistant, weather strip made by TESA, #7495 , 24mm X 12mm thick which hasa very sticky back that some have used with great success, especially if the inner cover is past it's prime condition. That includes myself, 4 years on and nary a drop.

Permalink

Previously ian_cordes wrote:

Paul. Do you use that instead of the rubber seal? Presumably you stick it to the inner case?

paul no i do not use it instead, but with the rubber seal as well

Permalink

The polyethylene TESA strip is 24mm wide (1") by 12mm (1/2") thick.It is stuck on the flange of the inner case, using the adhesive it has under the protective 'peel off' strip.The original rubber band is hung up on a nail in the shed. There is NO space to fit the original AND the TESA strip. Grease is smeared on the mating face of the outer cover so as it can be slid (manoeuvred) over the TESA strip, compressing it as it goes.

Permalink

Does anyone know where to get Tesa 7495 in the uk? If not, I have some mates in Aus if anyone wants to go shares?

Dan

Permalink

I am definitely up for trying this. Does it need changing whenever you remove the chaincase Paul?

I would go in with you on some Dan. I was going to suggest a group buy, but the larger the quantity, the more likely it will be hit by import duty. If Terrence wanted some, we could maybe get a roll between the three of us.

You would think there was an equivalent product here in the UK though, wouldn't you?

Ian

Permalink

Available in the UK too: https://www.hadleigh-tapes.co.uk/scapa-3259-12mm-thick-black-pvc-foam-tape_2778962.html. Just about to order some myself.

Handy hint: To protect your pristine garage floor, park your Norton on top of a flattened out cardboard box. IKEA cardboard works well. And then come November 5th, you will have a handy pile of oil-soaked cardboard for getting the bonfire going.

Permalink

I used Scapa 3259 PVC foam tape 25mm x 12mm with reasonable success. Had to chmafer the edge to get the out case on (plus grease) but it's a good tight fit. Dn't forget to put the join at the top! I got it from Self Adhesive Supplies. Ian - I've still got some left in "the shed".
Permalink

Ian, I have removed and replaced the outer two times with no leaks after. Though, I recently did replace the foam when trying to stop a sudden slow drip of A.T.F. oil emitting from somewhere beneath the primary.I then discovered that the slow weep was apparently coming from the bottom rivet which fastens the mount bracket to rear cover to frame. Bit of a trap there, I feel, as it was the last thing I would have thought of. Drilled both rivets out and bolted a plate on the inside with a good coat of RTV silastic on a thick gasket all sandwiched up.

Permalink

Good info Gents! We don't need to pay import duty after all! Is that a mail order company you refer to, George? I am slightly concerned about your description of reasonable success; that sounds to me as though it still leaks a bit! Seriously though, if you have sufficient spare, I wouldn't mind blagging some from you.

Ian

Permalink

One day I was short of time and the Silicone goo I normally use to seal my primary cases. So as a desperate temporary measure, I squidged a bead of 151 Black Roof and Gutter Seal in the outer cover and then stuck all the bits back together. I then filled the primary case with some transmission fluid and rode off to an event. I must admit to being quite surprised to find only a small single drip fell on to the road at the end of my journey. This was cured with a quarter turn of the centre nut.

A year later with no more leaking I had to pull my Dommi apart to do a major engine rebuild. The primary cases parted easily without the usual need for a truck tyre lever. I discovered that the 151 goo had bonded to the metal and rubber seal but not hardened in its centre. I used the 151 goo again after the rebuild and once more obtained a drip free seal from a primary case that previously used to be a huge embarrassment on every run.

You can buy the goo at 99p or £1 in some cheapo shops.

Permalink

Did the goo scrape off the metal and the rubber seal fairly easily, Phil? The foam strip that I used is a tad too thick at 12mm so needs to have a chamfer cut along the front (outer) edge to enable the cover to fit properly. I cut mine slightly wonky hence the "reasonable" seal (odd drip) rather than perfect (no drips). George
Permalink

Every time I make a change I think I've cured it. But the problem comes back again every time.My prewar single 16H chaincase seems to be thicker steel and is much deeper section so is far less prone to being distorted by the pressure of the nut. Post war featherbed ES2 is similar. So I suspect the Dommie design was over-stretched. Even so - the 16H still leaks. But then so does the gearbox and the crank case.Nobody much cared in those days. Cars always used to drip from the crankshaft end out of the bell housing didn't they? Car parks and drives always had a black patch under the engine. But they don't (much) nowadays.
Permalink

Previously Paul Knapp wrote:

â?oil resistant, weather strip made by TESA, #7495 , 24mm X 12mm thickâ?

Paul, I couldn't find this tape anywhere even tesa.ch don't know it.

Do you know a supplier?

Fritz

Permalink

A similar product is listed here: https://www.hadleigh-tapes.co.uk/scapa-3259-12mm-thick-black-pvc-foam-tape_2778962.html I copied the link from above but notice that it is PVC not PE? Not sure if that would make any difference?

Tesa Australia have it here: http://www.tesatape.com.au/industry/tesa_industrial/single_sided_foam/polyethylene_foam/tesa_7495,i.html

And you can buy it here, but you'll need to get it posted! https://www.blackwoods.com.au/part/00420558/tape-foam-tesa-7495-48mm-x-7m-grey

Permalink

Ian - sorry - just noticed your embedded query re Self Adhesive Supplies. If you Google Scapa 3259 tape, it will be one of the suppliers. George
Permalink

Previously George Phillips wrote:

â?Scapa 3259 tape, it will be one of the suppliers.

Thank you George.

Unfortunately it's not the same, it's PVC not Polyethylene.

Fritz

Permalink

Previously Dan Field wrote:

They may not but I have friends in Aus who can help !

Thank you Dan,

I'll send a PM for further negotiations.

Fritz

Permalink

Previously Fritz Wettstein wrote:

Previously Paul Knapp wrote:

â?oil resistant, weather strip made by TESA, #7495 , 24mm X 12mm thickâ?

Paul, I couldn't find this tape anywhere even tesa.ch don't know it.

Do you know a supplier?

Fritz

..............................

G'day Fritz, look up at my first post Monday, I have given the supplier I buy my tape (and other rubber goods) from. Their site says they will post.

Paul

Permalink

Previously Paul Knapp wrote:

G'day Fritz, look up at my first post Monday, I have given the supplier I buy my tape (and other rubber goods) from. Their site says they will post.

Paul

I'm sorry Paul, I haven't noticed this contribution.

Fritz

Permalink

Just noticed an artcle on the June issue of VMCC mag which notes that "Extra Thick Stormguard Weather Strip" does the job very well. Sounds cheaper than the stuff I bought. Have to admit the author used it on a '52 AJS, if that makes any difference. George
Permalink

You don't seem to be able to buy directly on line if you want shipping to the UK (it doesn't accept our postcodes!) but I emailed one supplier who is happy to post a roll, they reckon shipping will be about $30. The 7m toll is about $20 and if we allow for VAT etc that would be about $70 (assuming it gets caught by customs). I expect we'll get 5 or 6 out of a 7m roll at 58p to a dollar itwould work out at about £7 per seal.

I know Fritz is interested is anyone else? I imagine the foam will be good for battery boxes and a host of other applications! I'm happy to do the ordering.

I couldn't see any Storm guard tape that was 12mm thick or as wide as the Tesa stuff?

Permalink

Thanks to the link from Gordon and Dan to Hadleigh tapes, I've ordered 6 metres (!!) of 19x12 section PVC tape. I'll keep you posted on results.One worry to consider: a WD 16H web conversation includes reports of very small clearance between the outside of the clutch and the inside of the chaincase. So when I get my 16H chaincase back on (it's off in an attempt to replace the rubbers) I'll put some blutack on the bolts to check.Just to make it more complicated - the Dommie should have a thicker band than the 16H. So I might have the same (or opposite) problems on each.
Permalink

Well - 19x12 is too big for the Norton Single. The width looks OK but I've given up trying to put the case on. Maybe 8mm or even 6mm might do the job.19x12 might be OK for a Dommie where the original band is bigger anyway. One day I might find out.Incidentally - I oiled the glue side just in case I might need to take if off. I'm glad I did.David
Permalink

If an oil bath chain case is not distorted (and if it is, get it straitened), it should only need a smear of grease on the deal. Mine does not leak, after 62 years. Don't over tighten!

 


Norton Owners Club Website by White-Hot Design