[vhgmcbuddy]

Oki doki and thank you. I will try and call on Monday.

I also tried Silver Fox and got no response!

Surely there are more than just 2 or 3 people in the whole of the UK who have an interest in Bristols?

[vhgmcbuddy]

Valves.
Tucked away somewhere I’ve got one of those reciprocating valve-lapping tools – discarded very soon after purchase! For my money, the best aid to valve lapping is the “pneumatic twizzle stick” most easily obtained in the UK as a Briggs and Stratton part 19258.
Woods Power Grip. https://www.wpg.com/catalog/v12753
Various tips picked up over the years.
If the valve and or the seat is bad enough to warrant the coarse paste end of the tin – don’t bother, get the valve refaced and the seat skimmed. For a small extra cost it will be a better job and save time.
If the sucker on the twizzle stick wont stick, turn the valve over and rub the head over a sheet of medium emery cloth to thoroughly clean it and rough it slightly.
Slotted valve heads. Great for twizzling but not easy to lift up for the approved “lift and quarter turn” between twizzles! Search the odds box for a light spring, place it over the valve stem and trim to length so that it holds the valve head just clear of the seat, Press down with your screwdriver in the slot, do the twizzle, release pressure turn the valve and resume twizzling.
Valve size. Certainly, exhaust valves are often larger to aid heat transfer and resist the hostile environment in which they work, and a heavier duty spring will exert more pressure on the valve face to aid “self-cleaning” and heat transfer. However, don’t forget the configuration of the spring; often the coils at one end will be closer together. They are known as “anti surge coils” and the spring should be positioned with them furthest away from the collet or keeper.

Good valves are fundamental to a good running engine. No amount of fiddling with ignition or carburetion will compensate for bad valve sealing or clearance.

Quote from my favourite small engine repair book.
“Technicians who are valve critical will always have a better record of repair success than those who take a near enough approach”

To which can be added; “may add a little time in the short term but save lots later”!

British Junior Engine – anyone know why it was called that?
This may be useful https://www.dropbox.com/s/1uk2qwhdtojm5e9/British%20Junior%20engine0001.pdf?dl=0
However, it shows the same part number for both the inlet and exhaust valves; so may be your engine has been “modded” or it is a later variation. No date on the booklet but look at the phone number on the front cover – 1950s, I would think!

[vhgmcbuddy]

I sent off this email to ‘JWS8408@aol.com’, complete with pics but it was returned! Could you please help with another email address?

Hi there

I cannot remember contacting you previously.

I live in Johannesburg, South Africa.

I have a totally stripped Bristol 10 and two Bristol 20’s. The one Bristol 20 is going but needs some work on the steering clutches. I recently send the magneto/distributor to a guy in Northern Ireland. He successfully refurbished it and it arrived back about two weeks ago.

Bristol 20 up and going.

Bristol 10 parts that have been sand-blasted, primed and sprayed.

Bristol drive plates. The rollers were all shot so I machined and replaced all the rollers &
nuts & bolts for these drive plates – front and back.

The other Bristol 20 is basically complete but the restoration is going very slowly. There are a lot of pieces missing from the exterior of the engine. I have done a lot of work on the bodywork and the front grille.

Two new Bristol 20 aluminium plates were made from the one remaining sample.

New Bristol 20 bonnet.

One of the reasons for the slow pace on the Bristols is that I am also restoring a Caterpillar Twenty Two tracked tractor. Some time ago I restored a Caterpillar No.1 Terracer tow behind grader. The Cat 22 is a similar period tracked-tractor to pull this tow-behind grader. I have done a serious amount of work on this machine. So far I have done the tracks and completely restored the track tensioners. The radiator is now like brand new. I had to get a new magneto from the USA because somebody had attacked the original one with a big stone! … and so it has gone on and on and on.

Caterpillar No. 1 Terracer circa 1931

Caterpillar Twenty Two circa 1936.

Cat 22 completely re-built radiator with new core.

Do you know of anybody who would have some spares for the Bristols?

Regards

Keith Horwood
Earth Civils
+2782 564 8200

[vhgmcbuddy]

Thanks for this info

[vhgmcbuddy]

Yes, MAG was a Swiss company. Interesting observation about the valves; of the many Mag engined machines that I worked on, Multimowers, Mastiffs and Matadors, many having led a hard life with local authorities, I never saw a snapped valve. Possibly governors were being interfered with and the engines were over revving – we will never know.
Just done a service and sharpen on the later version of the Multimower

Attachments:

1. 
2. 
3. 

[vhgmcbuddy]

Well thank you all who have responded to this post.
As yet i have no settings of the mag engine to give it a good going over.
Does anyone know what they are and how many degrees do you time it to ?
Also what does MAG stand for as i have looked on you tube and nothing there either.

[vhgmcbuddy]

Thank you Neil.
Just Emailed you.
Andyham

[vhgmcbuddy]

I’ve worked on many ranging from early JAP engined to later MAG ones. Originally known as the Multimower as the reel head could be swapped for a rotary deck

[vhgmcbuddy]

Hi martyn -c also check your ignition timing as it is very important with a two stroke

[vhgmcbuddy]

could be coil giving warning of giving up, does it cut out suddenly or stutter ? if stutter I would look at carb. Villiers electrics sometimes give good spark until put to work then there is no resistance hence engine cuts out try simple things first like spark plug, condenser etc.

[vhgmcbuddy]

Don’t know whether he still does, but Chester Hudson of Horam in Sussex used to be good for old Howard stuff.
https://www.mdr.co.uk/tillerparts/tillerparts4.html

[vhgmcbuddy]

Did you have any luck?

[vhgmcbuddy]

Just out of inteest did you fit new valves if so which did you use?

[vhgmcbuddy]

Hi guys I’m completely rebuilding a 1947 British Junior engined gem.
After stripping down the engine I’ve noticed two different valves and different guides. I think somebody at some point has bodged a different valve and guide in. Any idea on a replacement valve? I can get a valve guide turned easy enough. I’m sure I’ve read that Landrover valves fit??

Thanks
Jay

[vhgmcbuddy]

Thanks, will find out tomorrow if it fits or not! Does anyone know where I can download or copy an instruction manual for the Auto culto Mk. 1X? I did try to go on the Auto Culto site, last night, But warned off by my computor security as Unsafe!

[Author]

Posts