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MG MGA - Oil Cooler Question

Is it reasonable that addition of an oil cooler should raise the coolant temperature in stop-and-go traffic? I added a 13-row cooler from Moss to my '57 MGA. At 30-60MPH the coolant temp stays at 195 as before, but in stop-and-go traffic it now goes up toward 210 pretty quickly (and did not go that high before). I do not run an auxiliary fan. Maybe my engine was better off without the oil cooler?
gdp poe

There has always been some debate on whether an oil cooler in front of the radiator can affect coolant temperature.
Most people, including the MG factory, believe that there should not be a problem.
However, some MGA owners fit the cooler to the bottom of the panel. Ensure that it it is not exposed to damage.
Maybe an electric fan would be the easiest solution. If you do not have fog lights you can use the fog light wire which extends to the front of the car, and use the fog light switch to control the fan.
Remember though that you are now putting another item in front of the radiator, but it should improve things.

Mick
Mick Anderson

If it worked before without problems, then just remove the cooler.

Adding something else (an electric fan) stikes me as being just another expense and something else to go wrong.

I have just bought an oil thermostat to fit in my system - I seem to have an overcooling problem on cold days.
dominic clancy

I had a similar problem. After relocating the cooler below the panel and cutting three two inch holes behind the bumper to flow air to it, the temp
stays below 200%. I run a 85% thermostat which narrows the operating temp to between 185 and 200. An electric fan cuts in occasionaly at 195 and together with a yellow [5 ?] blade mechanical fan provides a high volume of air to dissapate the heat. Sean
S Sherry

I relocated the horn and moved the oil cooler beneath the panel. Temp gauge now indicates lower temp than with the oil cooler in front of the radiator (about the same as before the cooler was added.) I don't know if this means (1)the oil cooler is not of any benefit to the engine, or (2)the oil temperature is in fact being reduced somewhat, but lower oil temperature does not necessarily reduce the temperature of the coolant. Maybe it just means that if you don't already have a cooling problem (I didn't)and you have a 51 year-old engine without an oil cooler, you should leave well enough alone.
gdp poe

Did you introduce an air flow to the relocated cooler ? I don't follow your reasoning that cooler oil does not effect coolent temp, surely they are both in the same boat
S Sherry

I'm simply saying that, based on my own observation, at low speeds the presence of an oil cooler in front of the radiator caused my coolant temperature to be higher than it was without the oil cooler. (It was not intuitive to me that this would be the case.) My presumption now is that the combined effect of hot air passing from the cooler to the radiator and the blockage of air flow to the radiator by the cooler apparently exceeded the coolant temperature reducing benefit of the cooler (mounted on the panel in front of the radiator). Relocating the cooler beneath the panel (and without any other modifications to air flow) seemed to restore the coolant temperature to approximately where it was without the oil cooler. I've read arguments pro and con as to whether an oil cooler will reduce coolant temperature. From my one non-scientific observation, I'm doubtful that it will at low speeds, absent other modifications.
gdp poe

I mounted mine under the front shelf. No problems with the hoses. I used spacers with longer bolts to allow the hand crank to fit through and work if I need it.
If anyone wants photos I could take some pictures, I just need help putting them on this page.
Tom Peotter

GDP Poe-
It sounds to me like you may have something wrong with your radiator- have you had it "rodded" out at some time? Have you flushed your cooling system? If you have to replace your radiator core make sure that you get a core with 3/8" spacing between rows of tubes and 3 rows deep. A fan in front of the radiator will only work at slow speeds and block air at high speeds. (however many cubic inches the fan motor blocks). My A stays at 180 degrees F.
Matt
M. H. Dabney

Matt, I don't know the condition of my radiator other than it has had nothing done to it in the last 12 years. Until I added the oil cooler, the coolant temperature stayed around 195 which I have presumed is in the reasonable range. (I like your 180 better.) I'm again at 195 with the cooler beneath the panel. I will keep your suggestion about the radiator re-core in my file in the event I need or decide to get radiator work done. Thanks.

Tom, what did you do--if anything--to direct more air flow to your oil cooler under the panel? Right now I'm a little conflicted about cutting holes in my valence. I have considered trying a deflector behind and slightly below the valence to direct air onto the oil cooler.
gdp poe

I mounted my oil cooler under the shelf on Doug Jackson's (British Automotive - www.mgbmga)advice.
I have to admit that I see no change in operating temperature. To increase air flow I cut a rectangular hole in my valance and made a grille, painted body color, to cover it. In my opinion, it actually improved the appearance of the valance. I wasn't smart enough to lower the cooler down for the crank and have no access to the dognut.
Randy

gpd, I did nothing to the valance and it works just fine. I find it hard to beleive that air does not blow
through the cooler even though there is a"curved" valance in front of it.
Tom Peotter

I have an oil cooler given to me by the PO -which I have not yet fitted - and I have just read the post about the cooling effect of synthetic oil- could this save fitting the cooler as it only gets hot after about half an hour running at 70 on the motorway.
Cam Cunningham

This thread was discussed between 26/04/2008 and 03/05/2008

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