sgc wrote:
drmini in aust wrote:
DON'T put the additive in a brand new engine, the rings etc may not bed in properly.
molybond.com.au wrote:
Molybond Formula 2.5 is a mineral oil dispersion containing 20% by weight of colloidal molybdenum disulphide, meeting the DEF2304 purity specification. Formula 2.5 is intended for addition directly to oil systems which enables the benefits of wear reduction to be achieved without changing oil.
- Available in 60g tube
- Reduces friction and wear
- Accelerates the running-in process
- Reduces oil temperature
- Reduces noise in gearboxes
(bold emphasis in the quote is mine)
Isn't that a contradiction? Reducing friction and wear is one thing and desirable... but it seems opposed to "accelerating the running-in process" which involves moving parts bedding into eachother.
When I read quotes like this (from the manufacturer!) it reaks of 'snake oil'. My experience with these type of additives in a Mini Engine / Gearbox is
NOT to use them in either a new or worn engine and yes they MOST definitly do cause havoc with the synchros and can cause damage if it is attempted to force the gears, but these little gems rely on friction for their operation and these friction modifiers don't allow the syncro rings to work correctly. You may seaming get away with it with new baulk rings, but as they wear their ability to expel oil reduces and so will give trouble sychronising. Yes, there appears to be a contradition, as I said as they wear, they will give trouble yet the friction modifyer will slow the wearing. In short if they don't wear, they don't work. This is why Mini's are factory fitted with a magnet on the sump plug. You always see the fur on them at every oil change? That material from the Baulk / Synchro Rings.
If you have a careful look at the design of the Synchro Ring, it has a series of grooves cut in to it's inner tappered face. These grooves work the same as that on a tyre in the wet, they are there to disperse the oil and cause friction to 'synchronise' the speeds of the shafts which are turning at different speeds. They are a friction clutch.
I have been overhauling (mostly) Mini gearboxes for over 25 years and a lot of the gearboxes that come before me 'because they grind in to gear' are simply resolved by changing out their friction modified oil, some with additives, for a 'standard' non- friction modified oil, such as Shell Super, usually a 20W50 or 20W60 is the go for Minis. Sometimes if these incorrect oils have been in use for a while, a 'flush' with diesel oil in need (say 200 - 300 kM) to wash all the nasties away. Diesel Oil is good for this purpose as it is high in detergents.
The reduction of zinc in oil was bought on by the EPA's of this world and is a major cause of oil seal failure because of the seals drying oil. This is what the zinc was added in to the oil for. It does very little for lubrication of metal to metal components. If Zinc was used for Metal to metal lubriction it would be available as a dry assemby lubricant for automotive and / or industrial uses, however other products are used such as wax and graphite are used. Not Zinc.
If the Synchro's still work after adding a 'friction modifier' then it icannot be a friction reducer as they need friction to synchronise.
Additives can also lead to an increase in Oil Consumption as the Pistion Ring Pack is not designed to operate with such oils / modifiers.
I don't use them, I don't recommend them and it will void warrenty on any of our reconditioned products.
But you don't have to take my word for it, have a look at what other car manufacturer's and engine / gearbox reconditioner's say about such products.
On the Asparagus Job I never saw less than 55psi at 100km/h (and never less than 40psi at idle) in a motor that's been doing city running for 8 years..
