BMC 1.5 - What is the best Oil for a BMC 1.5 + gearbox

[Goldilocks]

Hello I got some 15w 40 oil for my BMC 1.5 and was wondering if this is the best option for it and what quantity to put into once fully drained? If so does anyone recommend a certain brand and where to get it cheap? Also asking about the best oil for the gearbox? Appreciate all suggestions! Thank you 🙃 

 

all the best 

Goldilocks 

[Tony Brooks]

2 minutes ago, Goldilocks said:

Hello I got some 15w 40 oil for my BMC 1.5 and was wondering if this is the best option for it and what quantity to put into once fully drained? If so does anyone recommend a certain brand and where to get it cheap? Also asking about the best oil for the gearbox? Appreciate all suggestions! Thank you 🙃 

 

all the best 

Goldilocks 

 

You only get an answer because of your other post today, otherwise we need to know the make & model of gearbox. In this case the engine oil is fine for the PRM gearbox.

[Goldilocks]

54 minutes ago, Tony Brooks said:

 

You only get an answer because of your other post today, otherwise we need to know the make & model of gearbox. In this case the engine oil is fine for the PRM gearbox.

Alright Tony cheers mate! Thanks for giving me the answer 👍 you got any recommendations on brands of oil or where to purchase from? 

And is 5 litres a good quantity for the engine and gearbox? 🤙

[Tony Brooks]

That is an old PRM box and I can't remember how much oil it holds. BMC 1.5s can have different sized sumps so 5l may or may not be enough, I suspect it may not be enough.

 

You should not use fully synthetic or semisynthetic oil in the gearbox, but suspect semisynthetic would be OK, but not ideal for the engine.

 

15W40 is only a description of how "runny" the oil is. There are also letters staring with API (American Petroleum Institute), the groups of two or three characters.  You are only interested in the groups starting with a C ignore any starting with an S. Ideally the two characters following API would be CC, but that is a very old and obsolete standard. I suspect that you may have to be satisfied with CF, CG, or CH, possibly CH4. As the API is a performance standard, virtually any make of oil conforming to 15W40 and the API standard would do the job.

 

I think that you will find Morris oils and other brands selling a traditional range of oils will have a suitable oil - at a price. I used to use Comma oil perfectly happily and also supermarket oil of the correct specs. You might find what you want at a good price at agricultural suppliers or a heating oil merchant, but may have to buy in 20 l drums for the best price.

 

Others will have other ideas and favoured suppliers.

 

 

 

 

 

[ditchcrawler]

Wilco use to sell an oil of suitable spec. I did hear they were now trading on line, but I don't know if its right

 

Edited December 17, 2024 by ditchcrawler

[john.k]

Never use 'friction modified' oil in a boat gearbox.