Twin Engine Indentity

[Peter Holden]

Tony
with regards to the engine builders who is E?

[Tony Fearn]

Good to see you today at the AGM Peter.
Don't know about 'E', but I'll bet his surname was 'By-Gum'.
Tony.

[Chris Spencer]

Don't know about 'E', but I'll bet his surname was 'By-Gum'.

My dear Mr Fearn - You get sharper as you get older (Not stopped laughing since I read your response)

[BarryCambs]

Hi Tony

I'm just about to remove the oil pump from mine as the gasket is leaking badly when the engine is running. Reading your post above, is there something I need to know?

Thanks, Barry

[Tony Fearn]

Hello Barry,

It's nothing earthshattering, and perhaps most of us would know these days, but it's necessary to warm-up the aluminium engine casing around the oil pump to facilitate the removal. The first one I dismantled (when I was a teenager) finished up a real mess around the flange as I tried to chisel it out, not knowing then about the heat.

The pump itself, when you've removed the cover, has two threaded holes on the flange. These holes take, a couple of 1/4" BSF bolts (I think).

With the bolts in finger-tight, warm-up the aluminium and screw the bolts in alternatively, bit by bit. The bolt-ends bear against the engine block and the pump should be pushed out of its housing.

Tony.

[BarryCambs]

Thanks Tony, that's very useful to know

Barry

[george garside]

The late great Roy Bradock told me about the need to heat the crankcase for oil pump removal when, like Tony, I was in my teens.

He gave me the following instruction. ''Stand the crankcase on the gas stove in the kitchen - when its hot enough the pump will drop out - but make sure your mothers out before you do it!''

I followed his instructions to the letter, particularly the latter part!!

george

[julian]

Thanks for all the advice - the oil pump has now been extracted using 2 x 1/4 BSF bolts - note these need to be about 2" long or use a packing piece between the bolt end and the crankcase as the pump eases out.

Photo shows pump part way out...

IMG_6116-small.JPG

.. and then removed

IMG_6121-small.JPG

Unfortunately looks like some-one had a go before without using the heating & bolts method!! This is an old "injury" as the edges of the cracks were blackened with oil deposits and there are witness marks on the mating surfaces. I'm hoping it can still be used with the old pieces in place and a new gasket.

IMG_6124-small.JPG

[ian Howell]

I like the idea of using the pump as it is! After all it was working like that, but it might be an idea to 'lap' out the scores in the cover to at least reduce the amount of 'by-pass'.

I have a friend who is currently restoring a 1905 Clement V twin motorcycle (yes he did make a VERY few) with a cylinder head in much the same state.

Of course in that case there is cylinder pressure on the crack so it's not just a case of putting it together carefully. He is a skilled welder by profession but I am still awaiting the result of his efforts with great interest. A replacement casting would be a major exercise and the likelihood of finding a spare is . . .

[Andrew Henshall]

Hi Julian,

The oil pump flange on the pump in my 7 hp was in exactly the same state as yours prior to me disassembling it last year; I was lucky to be able to buy a replacement in Australia from a fellow JCCA member who had some engine spares! What would we do without the very helpful members of the various Jowett Car Clubs?

Andrew

[george garside]

[quote="ian Howell"]I like the idea of using the pump as it is! After all it was working like that, but it might be an idea to 'lap' out the scores in the cover to at least reduce the amount of 'by-pass'.




You may well get away with re-using broken flange as it will be firmly clamped by the bass plate although obviously a complete pump housing would be preferable.

If using the broken bits I would be tempted to put some gasket goo on the joins and drill and tap the base plate and broken bits to take a couple of small grub screws to provide positive location.

george

[julian]

Thanks for the advice, George.

I've now moved on to removing the cam-shaft. The gear wheel was a bit tight, but eventually came off with a 3-legged puller and a bit of heat. There are 2 x 5/16" BSF threaded holes in the pulley & I tried making a puller from a 1/4" steel plate I had handy, but it wasn't man enough for the force required and bent in the middle! I had been warned about the positioning of the pulley on the keyway (alternative positions are not at 120 deg) so marked the current position with a centre pop - just visible on the photo:

IMG_6128-small.JPG

Two nuts later and a bit of careful tapping with a hardwood block & hammer saw the cam-shaft emerge...

IMG_6130-small.JPG

All looks basically OK so will probably just clean up & re-install.

The engine is pretty much stripped down now, so I am getting quotes for re-metaling the big-ends & re-grinding the crank. It might be a while before I post again, depending on timescales and cost of the work. I have installed 2 new parts - the breather vanes and dynamo gear - courtesy the wonderful Jowett Spares. Thanks for all the help so far "I'll be back".