Oil filter housing and switch
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- Newbie
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Oil filter housing and switch
I have a 1969 1098 minor and noticed on the engine wiring loom there is a spare wire that is for the oil filter switch if it becomes blocked. My filter housing hasn't got the switch can one be fitted drilled and taped if so what is the part number for the switch.
- svenedin
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Re: Oil filter housing and switch
I have a 1969 with the original engine and it does have the oil filter head with the blocked filter warning. I think you might not have the original engine or perhaps the filter head has been changed?
As far as I know, the best way to return to original condition is to buy a filter head that has the switch in it. I actually have a spare I picked up at an auto jumble, brand new and unused so these do turn up.
Of course if you have a spin on conversion the head may well have been changed. It is actually possible to retain the original head, fit a special adapter and use spin on filters.
The part number is 37H1528 which is the Purolator filter head with pressure switch (blocked filter warning)
Of course, the filter should really never ever become blocked if proper maintenance is followed but it is nice to have.
Stephen
As far as I know, the best way to return to original condition is to buy a filter head that has the switch in it. I actually have a spare I picked up at an auto jumble, brand new and unused so these do turn up.
Of course if you have a spin on conversion the head may well have been changed. It is actually possible to retain the original head, fit a special adapter and use spin on filters.
The part number is 37H1528 which is the Purolator filter head with pressure switch (blocked filter warning)
Of course, the filter should really never ever become blocked if proper maintenance is followed but it is nice to have.
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen
- geoberni
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Re: Oil filter housing and switch
FYI, I can't find that number, the Lists I have are as below.
The non switch head is codified 37H prefix, the ones with a switch are 27H.
Basil the 1955 series II


- svenedin
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Re: Oil filter housing and switch
I didn’t look at my parts book actually.
https://www.somerfordmini.co.uk/head-wi ... assy-64-69
Stephen
https://www.somerfordmini.co.uk/head-wi ... assy-64-69
Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.
Stephen
Stephen
- geoberni
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Re: Oil filter housing and switch
svenedin wrote: ↑Fri Nov 15, 2024 1:41 pm I didn’t look at my parts book actually.
https://www.somerfordmini.co.uk/head-wi ... assy-64-69
Stephen

Knowing BL, the Mini probably had their own version with some insignificant little difference...

Basil the 1955 series II


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Re: Oil filter housing and switch
The standard Minor oil filter head cannot be modified to accept the blocked oil filter switch.
The filter head with switch was discontinued because it was found to be totally unnecessary because blocked oil filters are a very rare occurrence. Even if the oil filter does get blocked the oil still flows past the blocked filter element via the oil filter head bypass valve. The bypass valve operates at about 3lb pressure so there is always oil circulating through the engine.
The classic mini Cooper S had a blocked filter switch that bolted onto the filter head yet retained the element type filter.
https://www.ebay.co.uk/itm/364868847015 ... R9bB8YbmZA
I have one of the classic Mini Cooper S filter heads with switch available if required.
The filter head with switch was discontinued because it was found to be totally unnecessary because blocked oil filters are a very rare occurrence. Even if the oil filter does get blocked the oil still flows past the blocked filter element via the oil filter head bypass valve. The bypass valve operates at about 3lb pressure so there is always oil circulating through the engine.
The classic mini Cooper S had a blocked filter switch that bolted onto the filter head yet retained the element type filter.
https://www.ebay.co.uk/itm/364868847015 ... R9bB8YbmZA
I have one of the classic Mini Cooper S filter heads with switch available if required.
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- Minor Legend
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Re: Oil filter housing and switch
Fit on a spin-on head. Most, if not all, good quality spin-on filters have an internal bypass to maintain unfiltered lubrication if the filter becomes blocked.