Aftermarket oil filter fitting and flow.

[Leptons]

Oil temperatures on track seem to be getting a little high so I’m looking into fitting a remote oil cooler. The options for my car (e36 328i) seem to be to fit an M3 oil filter housing or use a modified oil filter cap, which I suppose is the equivalent of a sandwich plate.

My question is When using the sandwich plate type affair, how does the oil flow through the cooler? Effectively both ends of the pipes flow to the same place and I can’t see how the cooler gets a proper flow without using its own dedicated pump?!

[GreenV8S]

Leptons said:

When using the sandwich plate type affair, how does the oil flow through the cooler?

The sandwich plate is cleverly designed so that flow from the oil filter head outlet is routed out to the cooler, and the cooled return is routed into the filter and from there back to the oil filter head return. Preferably use one with an integral stat, otherwise add an external stat; the stat just provides a short circuit for the oil so it can bypass the cooler when it is cold.

[E-bmw]

As you say, with that car you are severely restricted in options as no-one makes a sandwich plate for them.

The M3 option isn't as simple as it sounds apparently it isn't a case of just bolting the new filter housing on as the take off for the vanos isn't there.

Just before selling mine I bought a spare filter housing with a view to getting it to a local machinist to effectively extend the bottom just below the filter to effectively fit a sandwich plate as the best option, then use a generic stat/cooler option.

[Leptons]

Interesting, I had heard the M3 housing needs fettling slightly. This is the arrangement I’ve seen, I suppose it’s like a sandwich plate in reverse but I can see how you get a genuine flow through the cooler. You’d be as well just drilling and tapping the housing?!

[GreenV8S]

Those pictures show a remote filter head, which is completely different to a sandwich plate. To use that you'd need to mount the oil filter remotely and plumb it back to the engine. You would have the option of passing that circuit through an oil cooler if you want. In this case you would need to use a separate inline thermostat.

[E-bmw]

Sorry, you obviously aren't aware of what the e36 bmw oil filter is like.

https://www.ebay.co.uk/itm/BMW-E36-3-series-M52-32...

The "cap" shown by the OP fits in place of the top of the normal filter housing.

It isn't a remote filter mount, it allows the oil flow to come up the housing, out of the lid, through an oil cooler/stat and then back & through the filter.

As the OP said it works "like a sandwich plate".

[GreenV8S]

E-bmw said:

Sorry, you obviously aren't aware of what the e36 bmw oil filter is like.

You're right.

As far as I can make out from that picture, the filter is a plain cylinder open at both ends and the standard cap blanks off the outer end so that oil has to flow through the filter to get to the center passage back to the engine. Perhaps there is some sort of pressure relief in there too.

For that other adapter to work it would need to have one spigot connected to the outer high pressure side of the filter, and the other connected to the inner low pressure side. In other words the cooler would run in parallel with the filter and act as a bypass to the filter. The pressure drop across the filter is what drives oil through the cooler. That's very different to a sandwich plate, which arranges them in series. It's not clear whether the adapter includes a thermostat.

How effectively it works and how much it compromises the filtration would depend on pressure drop across the filter.

Is there any way to get a conventional sandwich plate underneath the filter element?

[E-bmw]

GreenV8S said:

How effectively it works and how much it compromises the filtration would depend on pressure drop across the filter.

Is there any way to get a conventional sandwich plate underneath the filter element?

100% agree with the comment about flow/pressure, I never tried one for exactly that reason, my own take on it was to re-engineer the housing to allow a plate to be engineered into the original filter housing, that is the only way to fit an actual sandwich plate.

It needs a complete housing to be dismantled & machined & welded to allow it to fit, not a quick job & one that could only be done by someone that has a lathe & can alloy weld.

[GreenV8S]

E-bmw said:

It needs a complete housing to be dismantled & machined & welded to allow it to fit, not a quick job & one that could only be done by someone that has a lathe & can alloy weld.

If I had to tackle that - and thank goodness I don't - I think I'd look for ways to install a sleeve in place of the existing filter to bring the outlet and return flows to the top of that housing, and then use a remote takeoff in place of that blanking cap.

[E-bmw]

That is pretty much what the OPs pictured device does, but leaves the filter in place & still achieves it, although at a cost of around £150 IIRC.