MM oil filter

[Mr Spigot]

I need to get a new oil filter for my 1952 USHM3 engine. The current filter body is a Purolator. I have the choice of a paper or felt element, but is there much difference between the two, apart from price?

[myoldjalopy]

I have heard of people washing out the felt filter in petrol after use, but I wouldn't recommend it. Either a paper or felt filter will do the job.

[svenedin]

I use the paper element as sold by ESM in my Purolator and it appears to work well in that the oil stays fairly clean and the filter is very dirty at filter change time! Take care to assemble the internal parts of the Purolator correctly on reassembly as it is possible to do it incorrectly and have no filtering of the oil. If you do not know how long it has been since the filter was changed, it might be a good idea to have spares of the bottom seals at the ready. A new top o-ring is supplied with the new filter. In fact, there are two o-rings in the box with the new filter, only one is the correct size. https://www.morrisminorspares.com/search/purolator


Stephen

[oliver90owner]

‘You pays your money…..’ as they say. Not all filter elements are of the same quality, so your choice. Good quality paper elements are perfectly adequate, but do need changing at the prescribed intervals - as do all filtering media, of course.

Oil and filters are generally cheaper than major engine repairs.

It is like the modern spin-on filters with a bypass. Do you really know at what point that filter starts bypassing unfiltered lubrication direct to the oil gallery?

[philthehill]

The spin on/off filter head with the by-pass allows oil to pass through the by-pass all the time as the spring load on the by-pass valve is only about 3lb.
To ensure that all oil is filtered the by-pass valve can be blocked as per the picture below.

filter head 2 (1).JPG (1017.33 KiB) Viewed 544 times

The above modification can only be done to the type of filter head shown in the picture above. The classic Mini spin on/off filter head with by-pass cannot be modified.

[Chief]

So, did the Purolator heads use different seals or of the thick and thin seals included with filters, is one for Tecalemit and the other Purolator (and which is for which?).

[svenedin]

So, did the Purolator heads use different seals or of the thick and thin seals included with filters, is one for Tecalemit and the other Purolator (and which is for which?).

I’m not sure but what I do is fish out the old seal and fit the seal in the box that looks the same!

Stephen

[philthehill]

The oil seal for the spare Purolator oil filter head I have has a horizontal thickness of 2mm.

[Mr Spigot]

Many thanks for the advice. While I have a spin-on filter on my A series engine (and I will now check the bypass valve!), the MM one is the original side valve engine so I want to keep it original with the Purolator filter. Any preference for makes of paper filter? I have always been pleased with the parts from ESM so will stick to them unless there is a better option.

[svenedin]

This is the ESM filter. It is good quality. The Haynes manual says to change the oil every 3,000 miles and the filter every 6,000 miles. I may not do 3,000 miles in a year so I just do an annual oil and filter change because changing the filter is not a lot of extra work (but it is messy). Lots of fairly short journeys (which is what my car generally does) is worse for the oil than fewer longer journeys. You can see here that one of the top seals has a thicker wall. The seals also have a slightly different diameter. I cannot remember which is which but as I said before, fish out the old seal with an o-ring pick or screwdriver and then compare the old seal with the new ones. It will be obvious which one to fit.

Shop around for oil but ESM are often very competitive on oil prices for Castrol Classic.

Stephen

IMG_9733.jpeg (2.6 MiB) Viewed 469 times

[Mr Spigot]