Oil Coolers, Cooler Hoses, Fittings, and Catch Tanks

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The rotors in a rotary engine are cooled by oil sprayed into them from the eccentric shaft. They hold a considerable amount of oil that is continually being pumped in and over flowed out. The factory oil coolers are the best we have ever found for cooling capacity. Virtually all of the aftermarket ones are not even remotely usable. Do not run your engine for anything more than about 15 minutes with out an oil cooler.

The water-to-oil coolers used on 83-85 12A's do not work all that well, and are not recommended for modified engines. The two small sealing "O"-rings under these coolers are very prone to hardening and then leaking. The visual symptom is a lot of oil under the cooler and around the rear top of the engine. Four of the "O"-rings (part number 10-1601-9954) are needed for the repair, which is reasonably straight forward, not all that hard, but very messy.

Do not over-tighten the steel fittings into the oil coolers as they are very prone to splitting the aluminum tube where the fittings screw in. The aluminum crush/sealing washers should be replaced whenever the fittings are removed or changed.

The factory fabric covered oil cooler lines give many years of service, but CAN fail if very old, or kinked, smashed, twisted, etc. To check your lines, clean them thoroughly, then run the engine for a good while and look for any seeping through the fabric, around the fittings, or at the sealing washers.

These braided stainless hose sets are highly recommended if you need to replace lines, want added protection, and/or prefer the "racing" look. They are also less expensive than the OEM cloth covered hoses which are also listed below.

Braided Stainless Hoses with -AN Style Ends
Year	Model	Part Number	Adapters/Washers needed	Image
72-78	RX2, 3 ,4	11906	(3) of 11901 (1) of 11902 (3) of 41-6000-9956 (1) of 41-8000-9956
79-82	RX7 w/cooler under radiator	PT11907	Comes Complete with all the adapters needed
84-85	13B GSLSE	PT11908	Comes Complete with all the adapters needed
86-92	13B Turbo and Non-turbo	PT11910	Comes Complete with all the adapters needed

Dual Oil Cooler Kit
	93-95 Contents: - 2x Mocal Oil Coolers - 1x Oil Thermostat - 1x Tubular 45° - 2x Tubular 90° - 2x Tubular 150° - 2x Tubular 180° - 1x Straight - 1x Female 90° - 2x Adapters (18mm to -10) - 2x Crush Washers - 13 Feet of Braided Stainless Hose - 8x Adel Clamps Click here for a guide on installation	TT-COOLER-SET

Oil Cooler Thermostat
	Oil Cooler bypass thermostat -10 AN male fittings 180 Degrees Use when building an oil cooing system with aftermarket cooler(s).	A0T2-3

Oil Hose Retaining Clip and Connector
	93-95	14-6220-N3A1
	93-95, 04-ON	14-8500-N3G1

Oil Line Adapters for -AN style lines Click HERE if you are planning to build your own lines.
Adapter	Location	Sealing Washer		Image
11901	Front Cover (all through 92) and 74-85 Oil Cooler, 16mm	41-6000-9956
11902	Rear Housing of Engine and 93-95 Front Cover, 18mm (also fits 86-92 Coolers - but only needed if you are making your own lines)	41-8000-9956
-10 to 18MM 90°	Designed specifically for 86-92 RX-7's to fit in between the oil cooler and frame rail, where your conventional 90° bend will not. Also works for 93-95 oil filter tower, which is 18mm if you are making lines.	7736-9010M18

-10 Braided Hose, Hose Ends, Plugs, and Caps
There are some custom applications where the available oil cooler line sets will just not work, and special length lines need to be assembled. We carry -10 ends in either straight, 45 degree, or 90 degree, as well as -10 hose. Pre-assembled sets, to fit specific years, available at : Oil Cooler Line Sets
Description	Part Number	Image
Straight Hose End	-10-END
45 Degree Hose End	-10-END-45
90 Degree Hose End	-10-END-90
HOSE (sold by the foot)	-10-HOSE (1 ft)

Oil Line Adapters
79-85 Oil Cooler Adapter Fits between front of stock oil cooler hose and oil cooler	41-200F-9938

83-85 12A Steel Oil Cooler Line	Part number 14-720B-N231
	This line goes from the oil cooler under the oil filter, to the front cover of the engine. It does not tolerate any bending! They get bent when they are disconnected from the front cover, if the engine fitting is not held with a thin 21mm wrench. If it cracks and starts leaking, it makes a BIG mess at the least, and will cost you your engine at the worst.

Factory Oil Coolers
	Application	Part Number
	79-82 12A	14-700A-8871
	84-85 13B GSLSE	14-750D-N304
	86-92 13B All	14-700A-N326

Oil Cooler Mounts
	79-82 Left	15-3120-8871
	79-82 Right	15-312A-1128
	86-92 (2 required)	14-7050-N326

Sealing Washers
	Sealing Washer/Rear Banjo (two required) or Sealing Washer for 86-92 Oil Cooler (two required per Banjo bolt, 4 per cooler)	41-8000-9956
	Sealing Washer for Fitting in front cover + (2) for 71-85 front mount oil coolers	41-6000-9956
	O-ring under oil filter tower (2) for all RX, except 83-85 12a use (4) Sold "each"	10-1601-9954

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