Hello all, I purchased my first r53 about a month and a half ago. Its a preface lift 2004 MCS with 120k miles on it with no service history provided to me. I got it for a steal considering how much others were going for in my area. Well anyways I've already started wrenching on as there was things I wanted to get done so I could have some peace of mind. Unfortunately my plans and what the car decided it needed the work done is on two different time frames. After the first week of owning the car the harmonic balancer separated about a mile from work. Luckily in some respect the belt stayed on the remaining rubber which allowed me to limp the car to work so I could get it towed home. The downside is that when the pulley went it took out the CV boot and bounced into who know what else.

Well $600 in parts later and having to have the CV shaft cut and pressed out of the hub I'm back on the road. Thanks to both the crews at MiniMania and Way Motor Works as they both had the parts that I needed. I figured that since I was down there I replaced the front main seal and did an oil change as well as installing a new passenger side CV axle. Now I'm playing wack a mole with gremlins which I believe were partly caused by the pulley going out. The gremlins I'm working on addressing now is a low pressure oil light at idle after warm up, leaking thermostat housing, and motor mounts.

I've already checked the oil filter housing and everything is good and in working order. Non-OEM Oil filter has been reinstalled twice now, both times in trying to address the low pressure issue. So far the filter doesn't seem to be the cause of the light. I have noticed that the light does flicker sometimes when the car is idling so I'm thinking bad sensor or wiring as I have seen this same issue in other threads here on. To ensure that it is either a bad sensor or connection I'm considering installing a mechanical oil pressure gauge for the peace of mind.

The leaking thermostat housing is pretty self explanatory as I intend to replace the housing, thermostat, and the seal all at once. The motor mounts need to be replaced as they are shot. The upper mount that is bolted to the strut tower I'm considering just replacing with the complete Powerflex bushing if I can get the old one out without needing a press, but can't seem to find any info on if I will need the use of the press to do so.

 

Welcome to the forum

 

Thanks for the welcome . Just got my first Mini
2008 Automatic , looking forward to learning
more and getting acquainted with my Mini

 

Welcome to NAM.

Be careful with low oil light, it may not be a gremlin and you will end up with toasted crank bearings. I am wondering if the oil pump was affected by the crank pulley.

 

I am being careful with the low pressure oil light which is why I'm considering the mechanical oil pressure gauge. I've seen the light flicker on and off while sitting at an idle. Until I know for sure one way or another I try to give the engine some gas until the rpms get above where it turns off. The only time the light comes on is after the car has warmed up, but there isn't any consistency as to when it comes on as I have had days where the light hasn't illuminated on my drive to work or home.

 

Welcome
the thermostat and gasket is pretty easy as we keep them in stock since we do them often.

For the powerflex bushing in the engine mount you can get the old one out without a press, but you have to cut the outer ring of the rubber bushing to get it to pop so you can get it out. But a press makes it easier as that is how we do it for our prepressed option.

for the oil pressure is't very rare that it is anything other than in the housing or the filter so I'd recheck that.

 

Thank you for confirming being able to replace the bushing without needing a press. I'll most likely be going that way when I'm ready. I'm more concerned with the oil pressure light as mounts are useless if I blow the engine due to lack of oil. Its there anything specific that I should be looking for? I have already checked the low pressure valve in the housing twice now as well as removing and checking the placement of the filter. The filter is a WIX brand filter, I've also retained the filter I removed when I did the oil change in case I needed to compare it. In the case of the valve it was by taking a picture of mine and comparing it to known others with problems.

 

Hi and welcome to NAM! Keep us posted on your progress!

 

So after poking around I'm not convinced that thermostat housing is bad yet. The weather recently changed and I noticed that my oil pressure was getting more funky then before.

Since I've bought the only fan I ever seem to hear is what I take to be the high speed fan. I can hear it from time to time, but the most noticeable for me is after i park the car and turn the engine off as it continues to run for at least another minute or more.

After reading thru the thread about failed fan resistor i started wondering if my low oil pressure issue is due to a failed fan causing engine to run hotter making the oil lose viscosity. Right now the oil has about 1k miles on it but seems considerable darker then when it was fresh. I am aware that the oil will darken over time, but this feels rather fast. When I run the A/C system i have been noticing that the low oil pressure light requires higher RPMs before the light turn out. Would running the A/C generate more heat for the engine as its putting more load on it? I know when the high speed fan kicks in i notice a rise in RPMs needed to keep the oil pressure light off. As soon as the high speed fan shuts off though i notice that the needed RPMs drop below the previous level that was needed. If I don't run the A/C system i notice that it takes about 800-900 RPMs before the light goes out.

Any thoughts on of the issue? I have no problem changing the oil and the filter out if it's toast. I just rather not until i have the cooling issue resolved as there does seem to be an issue.

 

Usually when the light comes on it because there is an issue and when the motor is involved I would want to know real fast what is going on. A sensor is not that expensive and a whole lot cheaper than a spun bearing. Change out the sensor, if you still get the light then the next step is the oil pump, that is if the engine is still any good.

 

Is there anyway to know if the sensor is bad before just replacing it? What is the chance that it went bad just by changing the oil? If the sensor was bad wouldn't it shown up before when i first bought the car? I'm just trying to understand what makes you think it might be the sensor.

 

This is long distance diagnosing. Cannot see or hear your car.

Low oil light comes on = 1.) Low oil, 2.) Bad oil pump, 3.) Sludge in engine or 4.) Bad pressure sending unit.

You can buy a replacement switch for around $10. This would eliminate a possibility.As See posts #26 and 27 in the below thread.

https://www.northamericanmotoring.co...ng-leak-2.html

 

There is also 4 other possiblities that i have found related to low oil pressure. 1 is filter housing not sealing correctly. 2 is related to the brand and proper installation of the oil filter. 3 is the low oil pressure switch inside the housing is broken or missing parts. 4 is faulty wiring to the pressure switch. As for these possibilities I've already checked and i know i am not using an OEM filter. The wiring hasn't been checked yet as it is least common.

In regards to the 4 you posted above the oil level is correct. The pump would have shown itself before i changed the oil which it didn't. Number 3 is a possiblity only because i changed the oil when the motor was cool due to the hermanonic balancer being replaced it was changed at the same time. The switch being faulty again would have been seen before the oil was charged.

In regards to sounds and feel there is a slight roughness when the light does come on at idle. Other times when it requires 1500 to 2000 rpms for the light to go out the motor runs super smooth at idle, almost like the motor isn't running at all.

 

A leak big enough to impact the oil pressure is going to have oil blowing out somewhere so for me I would forget the oil filter housing. Not knowing the oil change intervals sludge buildup is still a possibility.

Just remember that things break and not when you want or think they should. Also, Ockham's razor comes into play here more often than not.

 

In the oil filter housing, there is a pop off valve and they are known to get debris and stick them open. This can cause oil pressure drop off, so check that valve, before thinking about an oil pump.

 

Right now I not experiencing any oil loss as i keep checking the oil every couple of days with no drop in oil. As to the change intervals i don't have a clue as i there was no service records provided with the car when i bought it. According to the last service interval on the cluster of the car before i changed the oil and reset it, it was past 15k. The only record i can find for service is thru the mini owners lounge which indicates that service 1 was done around 32k on the clock. That was 2 1/2 years into the life of the car. What happened since then is all a mystery.

In the picture above it looks like the drain back plug is raised, should it be when the filter is removed? Looking back at the last picture i took my drain back plug is sitting flush and is resting in a closed position.

I did buy a pair of seals for the heat exchanger when i thought it might be leaking. Since then I've looked it over twice and I'm not sure it is leaking as the whole area below the filter has caked on oil and dirt but no fresh oil on it. There are no oil spots on the ground either that i can tell as its parked in the garage almost every night.

I intend to order the oil pressure sensor and now a new O2 sensor as i just got code P0137 that comes and goes over the last couple of days. I'll be installing new motor mounts tomorrow as the front, upper, and lower are either shot or damaged. As to the radiatior fan the low speed is not working so I've already ordered a new resistor that should be here in the next couple days. When it arrives I'm going to make a trip out to my local scrapper to see if i can find a car with the plug and take both sides so i can fashion just a direct plug fix instead of cutting into the wiring for the resistor.

 

The 15 K is as high as it reads before it codes and often people change their own oil and do not know how to reset the oil change interval.
Make sure only to use full synthetic oil!

quote:In the picture above it looks like the drain back plug is raised, should it be when the filter is removed? Looking back at the last picture i took my drain back plug is sitting flush and is resting in a closed position. :end quote
Yes, it is up when the filter is removed.

Hoping you get her all dialed in soon! It is a process!

 

Since my drian off plunger is down when I remove the filter does that mean that I need to replace it? I have a thread saved that shows a plunger that we can use to replace it instead of buying the whole housing for just that part. It will require using the existing spring as the replacement spring is too large.

 

The photo is a revised "facelift" oil filter housing. There have been reported oil pressure light illuminated with discussion that may be caused by damaged to the bypass valve. This lead me to wonder the consequences and hopefully dispel some misunderstand. This is what I think but would like to be corrected if I am wrong:

Bypass Valve
The purpose of the bypass valve is to allow the oil to bypass the oil filter, should the oil filter become so clogged. When the filter becomes so clogged, the pressure in the chamber overcomes the bypass valve and force it open. The oil bypasses the oil filter should still circulate to all the engine parts at close to normal pressure, and no immediate damage should happen to the engine. This should not trigger the low oil pressure warning light. Of course, without filtration the risks of debris clogging a small oil gallery is very real, including the oil squirters.

Drainback Valve
The purpose of the drainback valve is to avoid the mess when replacing the oil filter. When changing the oil filter the proper and intended technique is to first loosen the oil filter cup, then unscrew it all the way but do not lift out the cup for a few minutes. This allows the drainback valve to open and drain off the oil in the filter chamber back into the sump (oil pan). By design, this drainback valve should be impossible to get stuck open, otherwise immediate loss of oil pressure will lead to catastrophic engine failure.

While by design the drainback valve should be fail-safe (i.e. should never stuck open as long there is a oil filter in the filter chamber), there can be situations that make it not so. Should a poorly made aftermarket filter (e.g. all paper without internal plastic cage) collapses badly and allow this drainback valve to pop open. The other possibility, while very difficult to do, is incorrectly installed filter element.

Minimania has a very good writeup on the Gen 1 pre and post "facelift" oil filter housing differences.

 

The largest worry as I see it, is debris causing the drain back plunger to NOT close all the way and decreasing the oil that flows through the system, which lowers the pressure at idle, but not enough at higher rpm to keep the light on, or gauge low.
This does not say the oil pump is not worn out, as high miles and dirty oil, is the damnation to an oil pump.
Sadly many auto owners in the USA, fail to keep their oil changed, in a timely manor. The oil is still good, but the contamination that the dirty oil is carrying through the engine can be abrasive.

 

One of my favorite snark is "You can devise a foolproof design, but they will always make better fools to defeat your best effort."

I can see a scenario which can defeat the fail safe design of the drainback valve:

John Doe bought all the consumables to perform an oil change. All goes as plan and he drain the oil, and proceed to replace the filter with the new filter he bought. To his amazement the filter does not fit because he was given a wrong filter. Being the Mini is his only transportation he thought, what harm can come if he just take a trip to the friendly auto parts store without the oil filter? It has to be better than putting he badly clogged old filter back in.

He proceed to replace the filter cup without a filter, and fill the engine with new oil. Just a short trip to the get the right filter and he will put it in when he return...

 

The build date for my car is 11/2003 which would make it a pre facelift car if I am correct. The current filter housing is a post facelift housing as it does not have the cage that goes inside the filter cover. I just double checked the old filter to make sure it wasn't stuck inside the old filter in case I am wrong. The current filter is a WIX brand that I've removed and reinstalled twice now to ensure proper seating.

 

It could be someone before you updated the filter housing. BTW, if I were to be in your shoes, I would rig up a test to find out at what PSI your oil pressure switch cuts in. That is an important data point to know what might have happen. The next thing is to find you what your engine's oil pressure is, with a gauge.

I think the stock oil pressure switch must be designed to cut in at only a few PSIs. With hot engine at idle with 5W30 even a very healthy engine can read very low at idle.

 

I have been considering plumbing a mechanical oil pressure gauge just so I can have peace of mind when the light comes on. If i remember correctly I read in another thread that the low oil pressure switch kicks the light on at or around 3.5 PSI which to me seems super low.

Anyways before I order a new oil pressure sensor I will get a new resistor for the radiator installed. It should be arriving any day now and after the install I'll see what becomes of the light then. I have a feeling that the oil is getting hot enough that it is thinning down and I'm lossing oil pressure that way.

Well I'm headed back to the garage for a bit as I'm in the middle of an AUX cable install and doing motor mounts.

 

While I know there would be some variation range from unit to unit, 3.5 PSI is consistent with my expectation. The nominal trip point is likely under 10 PSI.