Hitchcocks Forum

Merry Xmas all,

My last post was whether or not to split the crank case and check things out, or leave it.

I took the advice and split the crankcase, which was straight forward. I checked the bearings which are fine and the crank moves freely.

The other reason for taking it apart was that it leaked like a sieve when I put some oil in. The gasket material left when I split it was patchy. My question is, that when it goes back together, apart from the perimeter of the crank case and oil tank, should I be putting gasket material around the inside of the crank case as well.

You should. And use Wellseal only.

Other sealants will work just as well - I am sure Wellseal is probably good, but I have never used it and never had leaks as a result. Hylomar and Hermetite are both very good. If you really want to make sure even suspect joints don't leak, try Tiger Seal, although future stripping down may be harder as a result.

I have never used Wellseal but I do have a tube here
Usually what I do is Hylomar on one side of the gasket and grease on the other
Just remember only use the smallest amount of whatever sealer you choose if you can see a bead of sealer on the outside you will have a bead on the inside this can break off and block oilways in the future
Tiger seal is what Paul (bullet whisperer) used on the head of my asbo 30 and is working well
I have also used it on a Chinese 125 that was leaking badly from the primary side, the factory gasket didn't fit properly so the cases were cleaned well Tiger seal was applied to the inner case left for a few minutes then I applied grease to the other casing and tightened it up
The bike never leaked after and has since been sold without any comeback
For normal use I like Hylomar and always keep it on the shelf it works and best of all it lasts in the tube, I really don't like silicone it blocks oilways and goes bad in the tube
Hope this helps Dai

Thanks for the input everyone.

Hitchcocks have a complete gasket set for the Meteor Minor engine, but you cannot see the individual items. Is there a gasket for the crankcase/oil tank, or is it sealer all around?

Not sure about twins Peter, but Redditch singles don’t have a crankcase/oil tank gasket, it’s just sealer all round. Hopefully you don’t have any past screwdriver damage. My bullet used to leak like a sieve but splitting the cases and applying new sealant completely cured it.

Hi, unless the gasket sets have been upgraded, there is no crankcase gasket on twins. but it would not be difficult to make one if you can get gasket paper sheets large enough Vince

Thanks again for the input. What is the view about making a gasket for the crankcase. Is there merit in that over a sealer?

I wouldn't make and fit a gasket, as it would affect the overall width of the crankcase assembly very slightly and could cause other issues.

The twin engines have no gasket fitted between the crankcase halves, so please don't try fitting one - you'll almost certainly run into problems jamming up the camshafts when you tighten up the timing sprockets!

Prior to assembly, I lap each crankcase half on a pair of plate-glass pieces I had especially made (one has a circle cut out of it to permit the spigot to fit within it). I found this necessary as both sets of my Constellation 'cases had a casting/machining fault in the vicinity of the rear of the barrel mouths.

The crankcases will almost certainly be porous - my first Meteor Minor was still dripping oil 5 years after I had laid it up after having completely drained it! In the past I've had my 'cases resin impregnated, and have also repainted the insides with Glyptal (which is red rather than the original yellow colour).

I've always used Blue Hylomar for sealing the halves; it doesn't set hard and can easily be removed with acetone (nail polish remover) when required.