My 1950 VH

[david.anderson]

Keith
The ball seals in the oil return hole in the back of the oil pump. The hole is a machined surface but does of course have a very narrow seat. The narrow seat should however be regarded as ideal as it is far less likely to pick up a bit of grit, and it is of course a back up valve and not the primary valve.
David

[brenton.roy]

Hi Keith,
I'm replying here re your recent post re oil loss and buying the morgo.
A few years ago I had rebore trouble and seized a couple of pistons. This included bore and ring damage, and a loss of compression. One of the effects of this was a big increase in piston blow-by. The subsequent increased crankcase pressure acted to pressurise the sump. I had oil leaks all over the place, including through the magneto. I read that you have piston and rings that might not be matched to the bore?
The lower gearing I was then using had the motor revving a lot higher than it needed to. and so the problem was more obvious at anything above town speeds. I currently run a 24T.
My 1927 (total loss) holds about 200ml in the sump. When I drain the sump of my VH, there is usually somewhere around that much. I assume this is the amount that has been flung around the motor, returning after it has stopped spinning. I think I read that you have about this much in your sump (suggesting your return might be ok?)
It may well be that your oil pump return is a little weak (which the Morgo should sort), but if not, the above might be worth a look.
If the oil is coming from the breather, some riders fit a 'catch can', set up fairly high. This would help keep oil off the rear tyre.
Regards, Brenton

[Keith.owen]

Hi Brenton,
Nice to hear from you!

Strangely enough although the bore is towards the end of its life the compression always seems good and the engine starts pretty much first or second kick (probably thanks to the refurbished magneto) every time.

Normally it runs fine but on these two occasions when I lost oil from the breather the engine has started belting out enough smoke for me to be able to see it in the rear view mirror. Also oil has seeped from the gap between the magneto and the dynamo (the drags rubber seal is quite effective). Interestingly not much has come out of the timing side breather and the engine in general is pretty oil tight.

I have acquired another timing case and have fitted two washer over the return pipe. I shall try and see if I can devise a means of checking for any obvious air leaks before fitting the magneto drive sprockets and chain.

If after all this I still have a problem, I do in fact have a replacement piston +20 thou piston - the current one is standard. It's just I'd rather not have to go for a rebore just yet - plodding around at 30mph is a little hazardous when there's any traffic; drivers over here wear lead boots on their accelerator feet!!

BR,
Keith

[david.anderson]

Keith
I think that you still have to determine what is the cause of the problem. Going over old ground.
Next time you are blowing oil out the breather remove the oil tank cap and check the return. If you do not have a return then it is a pump or oil line problem.
Are you using an old armoured oil line to the oil tank. If so replace it. Otherwise check the line is clear.
Next the suction side. Did you remember the extra gasket washer (previously mentioned) over the oil pipe when you replaced the inner timing cover. That leaves the possibility of a loose or split sump oil pipe which is possible but is unlikely, and is a complete engine strip to cure.
Then there is the oil pump, which you have already changed so that is also unlikely. You also now have the back up ball to the return line so the possibility of 2 seats being dirty is very unlikely unless you have very dirty oil.
Now mentioned is the possibility of crankcase pressure. I may have mentioned to you that my bikes behave differently although the engines are similar. On one I use the standard down pointing crankcase breather. On another I have to point the breather slightly up from horizontal and connect a plastic hose to the end which I raise to drain back to the crankcase. The outlet I connect to a chainguard fitting which I use to lube the rear chain. My son has blanked his crankcase breather and just uses the timing cover breather. So if your problem is excess crankcase pressure the easy fix is to blank the breather (plastic hose over the end with a steel plug in the hose held with hose clamps) and just rely on the timing cover breather. It is also a safe way to run the bike to see if you have a wet sumping problem rather than excess crankcase pressure.
David

[Keith.owen]

I took her out for a ride today - went about 20 miles at fairly high speeds (50 + ish) and it appears the problem has gone away. Clearly can't say exactly what the cure was because there have been too many variables; two washer, another timing case, new oil pump. The good thing is that the oil is returning in a healthy stream , the level has not gone down in the tank, nothing has come out of the breather Except some mist) and there's no significant smoke from the exhaust.

Picture attached is after the ride showing off my newly painted oil tank!!

I'm not sure the timing is quite right though - could be a bit retarded because at higher revs the motor stops pulling - I set the timing through the plug hole so might need to re-visit this. However, it was great fun this morning and she goes well!

Keith

[steve.clarke]

Hello Keith
Glad to hear she running a bit healthier, have you checked your advance retard cable is properly adjusted to give full advance and your contacts are still set at 12thou? Before you retime.

[Keith.owen]

Hi Steve,
I set the timing on full advance and used a fag paper to find the point of opening. The whole process was not very precise!

I have not set the points recently, but the starting is reliable (usually 1st kick, if not second) so I have left them alone - I have only done 500 miles with the current reconditioned mag.

I shall see how it goes on some further runs. It's not normally possible to go too fast around here because the national speed limit roads just aren't safe at high speeds and the better roads are very heavily transited and speed limited.

BR,

Keith

[steve.clarke]

Ok Keith
I find the best way to set the points and advance is to whip out the dynamo it's only two bolts as you only normally only have to loosen one of the strap bolts and the wires as the points open just under dynamo, you then can see the A/R cable end,you can take up any play with the adjuster on the mag end also make sure the centre bolt on the A/R lever is tight enough to allow movement but still hold it's position, you may already know this but just a thought as all three mag's I have we're out of adjustment on the mag end, if you still have free play you may have cable stretch.
Cheers Steve

[Keith.owen]

All,
I took Betsy out again last night for another 20 mile ride.

The good news is that there are now no problems with oil coming out of the breather and at the end of the ride I removed the cap on the oil tank and the oil is returning in healthy blobs at tick over and if I increase the revs comes out as a stream. Also, I stopped the engine and the compression is good - can stand on the kick start.

Not so good - I think I have mixture problems and that she is running rich. She pulls well but at certain revs the engine stops pulling so she doesn't seem to want to keep galloping at above about 55 in top. It could be the timing is retarded also.

Having done some 580 miles on her and cured the oiling problem, I now have the confidence to start riding her harder.

I know I have asked this before, but having done a search on 'Amal concentric' couldn't find the emails that corresponded.

I have a 32mm Mk1 concentric fitted which actually mates with the inlet port. Could anyone who has the same size card fitted to a VH tell me what jet sizes and cutaway they are are using and what needle position. My carb is set up to the Amal default sizes and needle in the middle.

Hope someone can give some guidance.

BR,

Kieth

[david.anderson]

Keith
Australian fuel 98 unleaded 9 to 1 compression P1 franklin cam 32mm concentric
3 ½ cutaway
105 needle jet with needle lifted to highest position
250 main jet
I would guess with your fuel and engine tune that a 106 needle jet and a 270 or 280 mains would be closer. A bit of choke when on main jet will always give an idea if you are too lean as the performance will improve, especially if even more choke gives a further improvement. If a touch of choke immediately reduces performance you are probably too rich already.
you should start by checking your float height as a small change there will effect the tune right through the range. Set the float height as per the bushmans site. With the amal premier you can bend the float arm.
http://www.jba.bc.ca/Bushmans%20Carb%20Tuning.html
David