The Marston Sunbeam Club & Register Forum

General Category => Technical Discussion Forum => Topic started by: Peter 100 on November 24, 2021, 08:31:18 PM

Title: Oil in gearbox and chain case
Post by: Peter 100 on November 24, 2021, 08:31:18 PM
Hello to all
I have a newly acquired 1934 model 9.
Today I removed the drain plug on the gearbox expecting some oil at least to come out nothing. I assume it must have just grease in. I looked in the filler tube and there was some grease there.
So how do you know how much is in without dismantling the gearbox?
Also I have bought some Morris 140 oil as I have read quite a few use this. Is it recommended to use this on its own or with grease as well.
Any comments would be gratefully appreciated.
Oh yes and does the little oil bath chain case use the same oil as the gearbox as there was no oil in this either when I removed the case drain plug.
Cheers
Peter
Title: Re: Oil in gearbox and chain case
Post by: Thomas on November 24, 2021, 09:27:23 PM
Hi Peter,

I guess you have a four speed Burman box with grease nipples on the front side as indicated in the picture by red arrows. Then the box is lubricated by semifluid grease. With regular grease the gears clean out  the grease and leave holes. I can't tell how much grease should be filled. When working on my motor I filled it uo to the limit through the top openning, indicated by a green arrow and ellipse. After some hundret miles I give some squeezes with the grease gun and that's it. I have no idea where excess oil leaves the box. This is also mentioned in this nice little video: https://www.youtube.com/watch?v=8vneCzWUH4s

The primary chain case needs regular motor oil filled up to the drain plug, as indicated with a green arrow. I simply use my Castrol GP 40 or 50.

Cheers, Thomas
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 10:16:57 AM
Thomas
Thanks for the reply. I have checked my chain case and no fill hole like yours see photo I can only assume you fill via the silver inspection cover but would not really be able tell how much is in.
Photo attached of my gearbox it is a four speed but I am unsure what type again it doesn't look like yours with all those grease nipples although it does have the filling tube similar to yours.
Cheers
Peter
Title: Re: Oil in gearbox and chain case
Post by: Thomas on November 25, 2021, 10:21:44 AM
Hm, that doesn't seem to be a Burman box. Sorry, then I am out with advice. Yes, I fill the primary case through the inspection cover but now wonder how you can check the maximum level. Somebody else with a bike of your period must help.
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 12:14:10 PM
Thomas
On reading some previous post yes the primary chain case does need oil just to wet the chain and the level checked through the inspection cover as you say.
With regards to the gearbox I will wait to see if I get any other comments.
Cheers
Peter
Title: Re: Oil in gearbox and chain case
Post by: Thomas on November 25, 2021, 12:24:06 PM
Quote...and the level checked through the inspection cover as you say.

No, the inspection cover is the big hole at the chaincase top. There I fill in the oil. The oil level is controlled by opening the indicated screw at its bottom and waiting for overflowing oil.
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 12:32:49 PM
Thomas
I understand know sorry.
On closer inspection of mine it does have a similar indicator screw at the bottom but at the right hand side of the chain case not in the middle like yours. I assumed that it was a drain plug. So will put some oil in and let it overflow like you say.
Thanks
Peter
Title: Re: Oil in gearbox and chain case
Post by: Thomas on November 25, 2021, 12:47:39 PM
Here is a picture, just to be sure. The green arrow indicates the oil level controle plug (stop filling when the oil flows over) while the red one indicates the drain plug. The drain plug is always at the lowest position of the chaincase, of course.
Title: Re: Oil in gearbox and chain case
Post by: klaudius on November 25, 2021, 01:34:51 PM
Hello
Filling in oil in the primary box from above and checking the amount with the lower drain plug leads to empty primary box.
I bought a small rod camera for inspection from a cheap seller. Introduced through the upper inspection opening so that I could watch the oil supply.
With that I have achieved the following values. Oil 30 single range.
At 130 ml, half of the lower chain rounding is immersed.
After a test run, I reached 5 km of oily chain.
At 150 ml, the ispecification lid will start to tears after a few km. This oil prefers to hold on to the muffler and form a firm connection. I drive gear 140 oil and primary 50 oil. Operation only summer ... if you can call German summer that ...
Best regards
Claudius
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 03:52:49 PM
Thomas and Klaudius
Thanks for your comments much appreciated.
Funny I was only looking on ebay at those cameras they are not very expensive so would be a useful thing to have in my garage.
Cheers
Peter
Title: Re: Oil in gearbox and chain case
Post by: singleminded on November 25, 2021, 05:43:04 PM
Peter.
The sunbeam gearbox was supposed to have engine oil to lubricate it..
Some people like to use semi liquid grease, i use Morris 140 grade straight cut gear oil in mine..
the oil level plug for the gearbox is mounted on an oblong plate screwed to the front of the gearbox, it's up between the box and the back of the engine.Remove the square ended plug and fill via the fill tube till oil just flows out and refit the plug.
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 05:51:43 PM
Singleminded, cheers for that.
Being new to the set up I hadn't noticed that will have a search for it tomorrow.
Hopefully it will be above freezing in the garage!! 😁👍
I have got some of that Morris 140 so should be all set to go.
Ta
Peter
Title: Re: Oil in gearbox and chain case
Post by: klaudius on November 25, 2021, 05:58:36 PM
That's exactly how I do it with gear oil. I also attached a small round super magnet (they really are called that) to the lower drain screw, which protrudes about 1.5 mm.
Is obviously unnecessary but somehow it calms me down.
I check the oil level when filling up when the machine is on the main stand. Does not correspond to the actual tendency to drive but think they did it that way back then.
Claudius
Title: Re: Oil in gearbox and chain case
Post by: singleminded on November 25, 2021, 06:24:25 PM
if it's too cold peter keep a pair of scissors handy to stop the oil flow ;D..
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 25, 2021, 06:43:17 PM
Ha think your right. Bit of bad timing getting the bike at this time of the year, but they don't come up to often and it was the right one for me so had to get it.
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on November 26, 2021, 03:42:02 PM
Singleminded, found the square ended plug and got it out.
Now ready to add a bit of the slippery stuff!
Cheers
Peter
Title: Re: Oil in gearbox and chain case
Post by: klaudius on December 05, 2021, 10:01:43 AM
Hello
I urgently recommend dismantling and welding the gearbox, this is best done with a laser. Doesn't cost much. In my experience, such cracks become more and more up to total write-offs.
Greetings from Germany.
Claudius
Title: Re: Oil in gearbox and chain case
Post by: Peter 100 on December 05, 2021, 03:44:53 PM
Hello Claudius
The pictures you are referring to were posted by (singleminded) in connection with my question so you might be better contacting him with your concerns.
Cheers
Peter