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Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Cooper (R50), Cabrio (R52), and Cooper S (R53) MINIs.
Going to move you to the Stock Problems/Issues area.
Yes there is a gasket on the oil filter housing where it mates to the engine block. Modmini has a Youtube video on how to change it out. It is a PITA and made even worse if you have large hands. You are working by feel and when not up on a lift the bottom bolt is a real bear.
Best way to tackle this job is when performing an oil change with oil drained from the engine. That way, you can break down the housing into its smaller, individual components (cap, housing, oil-cooler), which serves to down-size the assembly, facilitating removal through the passenger wheel well. It's almost impossible to remove it with oil cooler attached. If it's separated, it can be removed without taking the axle out.
A positive component of separating the unit and removing the oil cooler (you'll lose a very small amount of coolant here) is that you can also change the oil cooler gasket seal rings (two required) that have likely turned hard and are seeping as well. If they're not, they will soon.
It is a fiddly, but not overly difficult job, requiring removal of a couple heat shields, and as r53coop says, working by feel. After removing the heat shields, study the location of the three bolts to become familiar with locations. The two at top can be accessed and removed from above; the bottom bolt is best removed from the underside. A magnetic 13mm socket is invaluable here - especially with the lower bolt, both for removal and re-installation. Be sure to properly torque the bolts (18 ft/lbs.) when re-installing. They're not very tight.
Last edited by AoxoMoxoA; Nov 6, 2017 at 07:26 AM.
Reason: Clarification
And if you have the unit removed, it is the time to tap the unit so that you can install an oil pressure sensor line instead of trying to use the NPT threaded units that are being sold here in the States.
The oil sensor (left side in the picture above) is a 3/8 British Pipe thread not a US NPT. The pitch is different. I had a vendor tell me the car had a Chrysler engine and since they were a US company the threads were US. Sure, an engine made in Brazil for for joint venture between DaimlerChrysler and BMW was going to have US threads.
And if you have the unit removed, it is the time to tap the unit so that you can install an oil pressure sensor line instead of trying to use the NPT threaded units that are being sold here in the States.
The oil sensor (left side in the picture above) is a 3/8 British Pipe thread not a US NPT. The pitch is different. I had a vendor tell me the car had a Chrysler engine and since they were a US company the threads were US. Sure, an engine made in Brazil for for joint venture between DaimlerChrysler and BMW was going to have US threads.
The challenge is where does one go to get the housing tapped for British pipe thread. One might think calling your local British auto garages. It will cost money on top of the wrong threaded adapter. If I already have the housing out, I would incline to just perform a hillbilly force tap with the NPT adapter which most are made of steel. With the housing out, you can see should you crack the housing or start to strip the soft aluminum threads.
No doubt there are hundreds of Minis with NPT adapters installed and have been lucky with hillbilly force tap.
If we are both wrong about our allegation the thread is BSPT, I would appreciate a vendor would step in and clarify.
Here is my Cravenspeed oil pressure gauge adapter which feel uncomfortably wrong-threaded tight at just 3 turns. You can see the shinny metal from the threads binding.
I know my Mini's oil housing thread has not been compromised as I am one owner. The stock oil pressure switch threads smoothly into it and with adequate number of turns unlike the adapter.
From what I have found you tap another portion of the oil unit with a 1/8 NPT and then route that to a remote point and connect the sensor. You can get 1/8 NPT fittings at most hardware stores in brass and then also in steel at specialty vendors.
Cravenspeed never responded to my rebuttal on the engine being a Chrysler and hence would have a US thread. It is just not logical to me that an engine made in South America for two European based companies would use a US thread. I wonder if the Oil Filter unit is made in Britain for a vehicle assembled in the same country?
pnwr53s, what is the material of the OEM oil sensor where it threads into the OEM Oil Filter Unit?
Won't work there; it's where the 10mm lower heat shield bolt screws into...
Yep! It took me a bit of work reviewing the housing images to come to same conclusion. There is no extra real estate on the filter housing for anything.
From what I have found you tap another portion of the oil unit with a 1/8 NPT and then route that to a remote point and connect the sensor. You can get 1/8 NPT fittings at most hardware stores in brass and then also in steel at specialty vendors.
Cravenspeed never responded to my rebuttal on the engine being a Chrysler and hence would have a US thread. It is just not logical to me that an engine made in South America for two European based companies would use a US thread. I wonder if the Oil Filter unit is made in Britain for a vehicle assembled in the same country?
pnwr53s, what is the material of the OEM oil sensor where it threads into the OEM Oil Filter Unit?
When I set out to plan the oil pressure gauge, I first consider the remote mounted sensor, but I decided against it due to the added cost and complexity. I opted for a simple mechanical gauge using a tiny 1/4" fitting.
I think you hunch is on the right track as the Tritek engine are also used in other European Chrysler cars and hence the BSPT.
The stock oil pressure switch thread is made of galvanized steel as you can see in my photo. I believe it is softer than the Cravenspeed T fitting. It has to be BSPT as the oil housing thread is.
According to this site, there are few differences for 3/8" that are quite troubling.
19 threads per in for BSPT vs 18 threads per in for NPT.
major dia of 0.656" for BSPT vs 0.675" for NPT
55-degrees rounded peaks and valleys vs 60-degree flat peaks and valleys for NPT
You can see why I said hillbilly tapping - intentional or not.
There is a post where the guy says he tapped the housing for the sensor line. Looking at the second picture there is that round stud just below the OEM sensor plug. I cannot do not know how the coolant circulates through the housing but would not think it comes in that far.
A 3/8 NPT/BSPT is allot larger than a 1/8 NPT so it could fit there depending on what is behind that area. I will look for that thread as this was one of my winter projects I was planning.
Good find. I scoured for a photo of the housing for this undrilled hole boss and I think this is it. It is the casted boss on the cylinder with small blind hole. It does not look like a location I would want to use as it would put whatever you use right under the red hot feeder tubes of the exhaust header.
this is one of the remote mount flex cable you were referring to?
A simple cooper tube and a brass fitting would most likely work as well depending on the tap point. I might try finding a junk yard or a busted housing to experiment on. In this latest shot would think the OEM sensor is in the stream that exits from the top right port as does that "blind" boss, so the question is what does the lower port or the three serve as there is that spot below the OEM sensor.
And by luck the Cravenspeed guy made a post today so I hit him with the question of the NPT vs BSPT.
I know we don't yet have solid proof that the gen 1 Mini's oil pressure switch is 3/8" BSPT. But base on the engine development and markets, and my hands on experience of my unsuccessful installation of the Cravenspeed T adapter onto the virgin oil filter housing port I feel the chance we are correct in this assertion is quite high.
If it isn't such a major PITA to take out the oil pressure switch (the oil will spill and make a mess) and carefully measure the threads per inch with a caliper I will do it in a heartbeat. The 3/8" BSPT is commonly designated as BSPT 3/8" - 19 to signify there are 19 threads per inch. Hence I would refer to the US counterpart as NPT 3/8" - 18.
Instead of waiting for someone else to jump in and help I want to resolve this problem myself.
This morning I realize that BSPT is used in many Asian countries, including Hong Kong, and may be China too. I tried to find a single 3/8" - 19 BSPT die and it is not too hard. An outfit in UK only want 65 Sterling Pounds plus shipping. In all fairness it must be industrial quality.
I then found some on feaBay for $8.23 apiece shipped from you guess where. I hope the quality is good enough for a 1 time use on the male thread of the Cravenspeed T adapter that is made of steel.
interestingly the photo has M16 blurred out - must be a generic product photo photoshopped on the cheap
to tap or not to tap - the second question of the day
I have neglected to address the female side of the Cravenspeed T adapter in my post above. The stock oil pressure switch seemed to engaged adequately with it. I suspect that it is just due to the major diameter of NPT is bigger than that of BSPT and the teflon tape is picking up the slacks between the mismatched threads. So to address the problem properly I will also need to drop $20 for a 3/8" - 19 BSPT tap as well from feaBay.
The Gen2 oil sensor is a m16x1.5 thread. A 3/8 NPT tap would be around 5/8" of inch when you consider that the port is 3/8" with an 1/8" of pipe surrounding it. I am wondering as MINI moved to the Prince engine did they do away with the BSPT and go with metric tapping? M16 is very close to 5/8.
Craven Speed has not responded to my question but then of course that was Friday so will see what they come back with. Hopefully I have Mr. Craven Speed himself and not some "Its a Chrysler" guy. The link to that thread is below. Perhaps what I found on the "Pond" threads of 3/8 BSPT are not correct.
A US thread on a motor/car that has metric everything else just does not make sense. A British thread on a metric designed system is more acceptable. Now what is that saying; if looks like a duck, sounds like and duck and walks like a duck . . . . . . . . .
Not sure if this helps or hurts the investigation here, so here goes.
The R53 had been having an intermittent oil presssure light despite correct oil level and no other symptoms. I replaced the original leaking switch that had 227+K miles so really nothing to lose by throwing in a new part.
I chose an Airtex 1S6670 after checking the airtex compatibility guide. It threaded in smoothly and torqued down with no issue. No oil leaks either. I believe it is an NPT thread.
with the NPT adapter which most are made of steel. With the housing out, you can see should you crack the housing or start to strip the soft aluminum threads.
