1988 Integra RS

I recently had the coolant leak problem in my 1988, 310K-mile Integra RS.

After doing a compressed-air test with my home-made tool, the leak was found from 2 thin hoses below the intake manifold: they were the in & out hoses, respectively, to a so-called oil-cooler (a doughnut-type hollow collar device) which was mounted between the engine body and the oil filter.

My question is: What’s the point of this Oil Cooler?

The whole cylinder block of the engine is being wrapped by water jacket; additionally, with the labyrinthic tunnels of oil mingled with the water jacket, why bother to set up an extra tiny Oil Cooling Collar?

Judging by the diameter of the hoses connected to the Oil Cooler, the coolant flow rate could never be significant enough to cool down the Oil at all — especially comparing to the Water Jacket effect.

Why Acura wanted to allocate money and labor to implement this Oil Cooling Collar if the device does not contribute much (if any) at all?

To fix my coolant leak problem, may I just bypass the Oil Cooler, and just use a piece of hose to connect the inlet & outlet (for the Oil Cooler) of the engine body? Could it be any bad result by doing so?

At 310k miles I would bypass the item. Use whatever it takes to stop the leak at this point in the game which is well past over.

Oil does not only lubricate your engine it is part of the cooling system.  I would want to keep it functioning, but with a car that old and that many miles, I would not want to spend too much effort on it.  If you can fixe it cheap, by all means do it.

Neither of these 2 coolant hoses are easy to access; still, I can get it done myself anyhow.

I wish I did not mislead you in my previous message. I know that oil offers both lubrication and cooling functions; in the issue I brought up, these 2 coolant hoses (1/4" inner diameter) are connected to a doughnut-shape small device (the sale of Acura dealer called it Oil Cooler; I am not sure whether that’s the formal name of the device) which, based on what Acura sale person said, is to serve as the Oil Cooler — that’s, the oil is to be cooled down by the coolant via this device.

My question is not how (hard) to fix the coolant leak, rather, why the Acura engineers wanted to implement this Oil Cooler — could it be my mistake in thinking that this mini tiny Oil Cooler could not offer mention-worthy cooling effect. Have you guy(s) ever seen any other car maker put a tiny Oil Cooling Collar between the oil filter and the engine body?

By the way, being as “senior” as a 310K-mile car, my 1988 Integra can still make 34 ~ 37 MPG in high way and has never failed the smoke check with only 1 test. I don’t see any convincing reason to give up hope to fix minor issue like coolant leak to it.


Maybe it’s there just to cool the oil filter mating surface?

Is the oil filter located above the exhaust pipe?
That’s how my '88 Accord was.

I see your point.

You actually had brought up another issue: The rubber O-ring of the oil filter will age as the hot oil keeps on flowing through the filter.

I have known some people who never bother changing oil but “refill” the oil tank for their old vehicles. They should at least concern about the O-ring getting aged and consequently get oil leak.

Yes, the oil filter is located above the exhaust pipe on my Integra. I don’t worry about that, however.

Heat is transferred in 3 ways: conduction, conviction and radiation. Since there is no contact between the the oil filter and the exhaust pipe (hence no way for heat conduction); and when the car is moving, most of the pipe heat will be dissipated by the open and turbulent air (the chance for heat conviction and radiation is also very slim).

When the car is standing still and idling convection can carry heat up to the filter.
I don’t worry about it either, but there were cases (mainly CR-V) of improperly installed oil filters leaking onto the pipe and causing a fire.