Engine failure troubleshooting

[mugwump]

An obvious question, but what do modern gear boxes use for bushing i/l of bronze.

[RDfella]

needle rollers and the like.

[berger]

modern gearboxes will have a different composition of bronze or brass and possibly use different 90 oils. the old BSA etc bushes have been known to have the copper content in the bushes  react with the EP grade oils firstly causing a type of dark shadow in the bush- sulphide- I think ,leading to the bush starting to wear faster than with a non EP oil causing fine glitter in the oil and in very warm hard working boxes failure of the bush

[chaterlea25]

Hi All,
There are books written (I'm sure) on how/why some gear oils attack bronze bushes 
As far as I know (very little) about oil it had to do with "Sulphur" additives in Hypoy oils ????
Some years ago I was given some "gear oil" and I  put it in the rebuild gearbox on my SR
A while later I just before a trip I checked the gear oil level to find "gold dust" in the oil 
A panic rebuild ensued completed just in time to catch the Ferry

John

[berger]

thankyou john it is the additives that attack and cause corrosion in the bushes with some oils --- Extreme Pressure oils and bronze = sulphide.  I ran EP 90 in my box for ages and when looking closely on an oil change on a nice sunny afternoon I saw loads of small pretty glitter. when I took the box off and put petrol in it and shook it and drained it LOADS of glittery bits came out. I stripped the box and found badly worn bushes. this is why I keep away from EP 90 and use straight 50 in the box

[Greybeard]

Just to check, I will drain my gearbox to make sure.

[JulianS]

Earlier this year, following some gearchange problems, I found the bush in the first gear pinion to be very badly worn. Oil looked quite contaminated with some gold colouring.

Had been using an EP oil. 

It is a needle roller box, no signs of wear on the other bushes in the sleeve gear.

Now using a Morris Lubricants non EP gear oil. Worth considering.

https://www.morrislubricants.co.uk/products/classsteam/classic-gear-oils/golden-film-ag90-classic-gear-oil.html

[berger]

JulianS sort of nail on the head, gold colouring is what I found  when I drained mine ,then after shaking the box with petrol in it larger bits came out. I see the oil thread you put up states NO Extreme Pressure additives, these are what cause the problem. my sleeve gears were affected but nowhere near as much as the layshaft that have a lot more contact with the oil

[RDfella]

Interesting thread. Old Ferguson tractors have lots of bronze in the gearbox / hydraulic system and we were warned decades ago not to use certain oils as they attacked the bronze. And so I didn’t, nor did I ever use those oils in my motorcycle gearboxes. Yet not so long ago on this forum, some were expounding the virtues of gear oil and chiding us for not using it in our motorcycle gearboxes, almost suggesting those of us who follow makers recommendation and use engine oil were some sort of retard. Where are these guys now?

[chaterlea25]

Hi All
RD,
I have for the last 40 odd years used whatever gear oil that came to hand in my bikes gearboxes
The only time I have ever seen trouble was with the "free"  gear oil
Over the winter I will need to go through the gearbox again sometimes it will jump out of third gear under high load
also the 3rd gear whine is getting louder
I am considering either fitting a splined mainshaft and home brewed Suzuki based clutch or a belt drive
The downside of the belt drive is that it would not allow the fitting of an electric starter
Joint pain has kept me from using the SR very much in recent times 

John

[ironhead]

I use Penrite premium mineral 80w90. used for all  gearboxes, diffs limited slip. Goes in blue & comes out blue.
Double checked on the label after reading this thread & says" compatible with copper alloy components".
Been running it in a B33 for over 5 years in constant use with no change in performance.

[duTch]

 As this thread is about Owains' engine problem which seems to be on the way to resolve  , I'll comment about my gearbox oil in a new 'Gearbox Oil' thread that Big Jim started....;

 https://www.a7a10.net/forum/index.php?topic=14648.0;topicseen

[Daveh67]

Interesting thread. Old Ferguson tractors have lots of bronze in the gearbox / hydraulic system and we were warned decades ago not to use certain oils as they attacked the bronze. And so I didn’t, nor did I ever use those oils in my motorcycle gearboxes. Yet not so long ago on this forum, some were expounding the virtues of gear oil and chiding us for not using it in our motorcycle gearboxes, almost suggesting those of us who follow makers recommendation and use engine oil were some sort of retard. Where are these guys now?

your quote on ferguson tractors is correct, i see many failures due to people using modern 15w40 engine oils in tea20 ferguson tractors.
the oil question will be my next task as my rebuild is coming along well. tinware is primed, engine barrels machined,  working on the sludge trap and timing bush now.
only have pistons plus small end bushes to order now. some chrome and zinc plating and i will be happily tinkering away.
new valves, guides and springs are on the bench. im not doing a 100mph rebuild but im a fussy old bugger and like things to be done right.
ive tried posting pictures but they are too big to post! need to get a teenager to fix that,
my rebuild will slow down for a while as harvest time is near and i will be burning the midnight oil keeping machinery moving.

dave

[BSA_54A10]

Interesting thread. Old Ferguson tractors have lots of bronze in the gearbox / hydraulic system and we were warned decades ago not to use certain oils as they attacked the bronze. And so I didn’t, nor did I ever use those oils in my motorcycle gearboxes. Yet not so long ago on this forum, some were expounding the virtues of gear oil and chiding us for not using it in our motorcycle gearboxes, almost suggesting those of us who follow makers recommendation and use engine oil were some sort of retard. Where are these guys now?

When syncromesh gearboxes became the nom the composition of gear oils was changed and truck gear oils separated from car gear oils as trucks used to have crash boxes.
For the following 20 years oils were marked "Syncro safe if they did not contain sulphur.
The sulphur was by & large replaced with zinc same as in engine oils.
Eventually when every car had a syncromesh gear box all car gear oils were syncro safe so that was dropped from the lable.
For those who do not know syncro cones are sintered brass
Thus almost every CAR gear oil will be fine in your BSA box
Some truck gear oils will be a problem .