14 replies to this topic

[Tinkerbelle]

Hello all,

I have just built a MG metro lump with Stage 3 head and twin HS4s. Does anyone have an opinion on whether I need an oil cooler? It had one as standard on the Metro (oil/water cooler) but would like to go without. The mini is just used for occasional weekends and mini runs?

I have the mini spares 13 row cooler kit and as per instructions drilled and bolted appox in the middle of the grill area, but it doesn't fit due to starter solenoid. Does anyone know of the best alternative place. e.g.

Thanks

Matt

[Dan]

I'd stick with the oil to water cooler if I were you.

[Tinkerbelle]

Should I loop the heater hoses through it? Do you know if it will screw straight onto the shorter mini oil filter housing as opposed to the Metro item.

Thanks

[Dan]

No it won't because it won't clear the block. The short housing tends to leak oil around its base anyway because the gasket area is tiny. You need to use the long housing and sometimes will have to relieve the subframe front member a little to clear the filter. I would not do that on a late (1992 on) subframe where the engine is mounted further forward without re-inforcing the frame around the cut out because there would be little original steel left in the top of the member. Tee it off from the heater circuit so it works independantly of the heater tap. These are far superior to oil/air coolers which tend to provide far too much cooling most of the time and slow the rate at which the oil warms up. Even the thermostatic type aren't great because they are all set to the same temperature which simply isn't right for many engines. The oil/water intercooler actually speeds up the warming of the oil and regulates the temperature far better. You need to make sure your rad is up to handling the extra heat load though.

[Tinkerbelle]

Thanks alot you have been a great help.

Lets hope the old oil/water cooler doesn't leak, its not been tested!

Matt

[Dan]

Realistically though Minis rarely actually need oil cooling, the sump makes a pretty effective oil cooler. Having just driven over the Eifel mountains at the peak of summer in ours we were still finding oil pressures of 25-30 Psi at a low idle speed of around 850 rpm. That was with very seriously warm oil after a long hot run up a mountain on the motorway followed by suddenly stopping and sitting at idle in a service station while waiting for people. Blip the throttle and it came right back up to 54 and stayed there for a good few seconds before dropping back and as soon as we were off and running again the pressure came up and stayed there. Still I am considering adding an oil/water cooler that I've had in the garage for a few years myself and from the sound of your engine build it is a worthwhile investment. Imagine though if I were to add an oil/air cooler to my engine without properly thinking about what I was doing, the oil would be cold almost permanantly.

Edited by Dan, 22 August 2008 - 10:34 AM.

[shough]

Hey guys just read the post...
I have been very interested in fitting an oil cooler... HAd mixed reactions about doing it.. Some guys said its not needed others said only if its an uprated engine and others said its a really good idea whether you have upgraded or not... I run a standard 1275 engine but want an oil cooler.. what are your thoughts...
I also dont know much about it but you guys are talking about water/oil cooler and air/oil cooler.. Can you explain the different types for me?

Thanks guys.....

[Tinkerbelle]

Yeah good points. My 1061 used to deal with being trashed around town in the height of summer (a long long time ago when the sun came out in summer) with cheap oil and kept good oil pressure?

I will save sorting out the oil cooling problem until I find it to be a problem - probably a good rule of thumb in general.

You've been a great help.

[Dan]

Can you explain the different types for me?

An oil to air heat exchanger is simply a radiator that the oil flows through and is placed in the airflow over the car. It extracts heat out of the oil and dumps it into the colder air, this is the most common type of oil cooler sold as an upgrade by all the Mini and tuning specialists. An oil to water heat exchanger is a device that is plumbed in to the oil and water systems. It allows engine coolant to flow through one circuit and oil to run through a seperate circuit, allowing heat to flow from one to the other. It extracts waste heat from the oil and dumps it into the coolant system from where it is shed into the air through the normal coolant radiator.

[Tinkerbelle]

Shough,

I am no expert but the difference is:

1) Some later high performance A series (MG Metro etc) were fitted with a oil cooler which bots between the oil filter and housing and runs coolant through it to keep the oil cool.
2) Early Cooper Ss had an oil cooler, which used air flow much like the regular coolant radiator, to keep the oil cool

Matt

[shough]

Thanks guys... Thats kinda what I thought but im never sure..... Which would be better surely the water/oil cooler but is that a bit risky in terms of leaks etc?

[Ethel]

An oil to air cooler is exactly like a little radiator the oil flows through - the type you'll find on all the car tuning suppliers sites.

An oil / water cooler transfers heat from the oil to the water, some Metros (MG's & Autos) had one that sat between the oil filter and engine with a couple of hoses connected to the cooling system. It could improve warm up as heat is kept inside the engine until the thermostat operates and it won't improve overall cooling as the heater still has to be dissipated from the water.

The best way would be to install an oil temp gauge and decide if an oil cooler is needed based on what it says related to the operating range of the oil you use.


I don't think leaks are a huge problem with either if sensibly installed and maintained, but an oil leak would lose lubrication as well as cooling.

Edited by Ethel, 22 August 2008 - 11:21 AM.

[Grayedout]

Remember early Coopers will have been using a lot poorer oils than we have now with lower resistance to thinning when warm.

Modern multigrades are much better quality and so do not thin as much with temperature and it's actually better to have a warm hot. Personally unless you are putting out over 100bhp I would say they are not required.

[shough]

Nice ok so gneral idea is that because of modern oils unless I'm pumping out a huge amount of BHP then I dont really need it... Thanks guys really helpful


Cheers... Its crazy the amount of stuff I learn a day just by reading and you guys have inspired me... Always wanted to pay someone else to redo my mini, bugger that now I want to do it my self even tho I know next to nothing..

[taffy1967]

The 1990 RSP Mini Cooper LE had an oil cooler as standard (I think it was just a 7 row job and had an 'Oxford' sticker on it?), but Rover realised that it wasn't really necessary (on a standard engine) and deleted it from the Mainstream Cooper and SPi models. It was available as an option though.



The Rover Mini Cooper came with what was effectively an MG Metro engine.

Edited by taffy1967, 22 August 2008 - 02:40 PM.