Frostycrowd

iTrader: (9)

Ok dont know if I spelt that right. But anyhow, I want to get a front mount oil cooler and am aware I need one of these, but I want one that also has holes for oil feed lines or gauges. If someone could link me that would be great.

StealthGXL

iTrader: (1)

http://www.mrcmfg.com/respeed/catalo...0a62163f835d6c

bliffle

Why do you want to switch to FMOC? Only reason I can think of is to obviate those pesky pedestal ORings.

chedda_j

mines leaking, thats why im changing mine, also makes it easier for the turbo app.

Racing beat has billet aluminum ones, nice ones too.

Rx-7Doctor

iTrader: (13)

The FMOC is alot more efficent at cooling the oil, that's the best reason.
Another is that the beehive is a pain in the *** to have on there. When you are trying to do things like change the clutch slave cylinder it's a major event with that huge thing in the way. And yes doing away with it makes it easier to change the o'rings when they fail(The pedastel for the regular mounting of the filter still has orings), it's alot easier to change though.

Frostycrowd

iTrader: (9)

well I am going turbo, and I dont think that behive can handle the load.

Rx-7Doctor

iTrader: (13)

It can't handle the load of the Turbo and going the FMOC turbo or no turbo is a GOOD idea.

nick812

I agree I would never run a behive unless i was getting ready to get rid of the car and wanted to keep the FMOC.

bliffle

How do you know? Is this a theory or does someone have some numbers?

dj55b

iTrader: (2)

I'm no wizard and I don't have any numbers for you, but using my common sense of the size difference of the 2, plus the fact the the FMOC is fed fresh air from infront of the car as oppose to the air that is being passed through the radiator and then from ontop of the engine to get to it, I can from there see how and why it would cool better ....

Rx-7Doctor

iTrader: (13)

Bliffle, I know you are intellligent enough that you don't have to ask for numbers to know that it is.

bliffle

Actually, the beehive stabilizes oil temp by putting oil in intimate contact with water at operating temp. The fins are to protect the fingers of careless mechanics, not to cool oil. Heat transfer from liquid to liquid is much much better than from liquid to air. By using a beehive the oil cooling sysem gains the advantage of the temp control systems in place for the engine coolant, i.e., a large radiator favorably sited in cool air, a thermostat to control liquid temps, and a controlled fan to expedite airflow. Do you propose to add those controls to the FMOC? By combining the oil and coolant control systems one gains the benefits of energy pooling systems, e.g., ability to handle wider swings in operating conditions.

IMO it would profit a person to install an oil temp gauge (having determined the best place to sense temp) and observe it carefully before making radical changes to an important subsystem like the oil system. It may be that the oil cooling system would benefit more from supplemental cooling than from replacement cooling. That is, add the FMOC without replacing the beehive.

bliffle

Thinking about it for 3 minutes, I decided that what I want is an RF oil temp gauge that consists of a sensor/transmitter that sends an RF signal to a receiver/display unit that I can have anywhere in the cockpit without running wires. That way I can move it among vehicles easily, and finally remove it when no longer needed, or leave it on the DD.

That way I can compare the oil temp characteristics between the 2 FMOCs in the SE and REPU and the 2 beehives in the 12As. Maybe I need 4 such sensor/xmitters so I can leave them in place and just move the rcvr/display unit (perhaps it has a suction cup so I can stick it to the windshield; or perhaps it projects a virtual image focused at infinity, just like Donald Campbells Bluebird in the 1930s).

Anyone know where I can purchase such an instrument, or must I fab it myself?

Now, THAT would be really useful!

Frostycrowd

iTrader: (9)

that would be cool if you could do this for the board

Midwest 7's

iTrader: (4)

yo biffle. of the many many 12a's i have torn down i can say for fact the beehive is junk.
cool oil with 190* water? yea right.
the older motors are waay more likely to have useable housings despite miles. i dont think i have ever got useable housings from a 83-85 motor with over 70k. the higher temps in the beehive motors are harder on the chrome plating.
when i see 83-85 12a's in the junk yards i leave them be, any other i will grab up unless the miles are crazy.
not cold hard facts i know, but keen observation from a hard core rotor head.

trochoid

iTrader: (6)

FYI, all rotarys have/had an FMOC, except the 83-85 12As. This series of engines has had more dowel pin o-ring leaks/failures than any other rotary engine. General consensus is it's due to them breaking down from excessive oil temps.


The FMOCs have a thermostat in them to control oil temps.

Side by side oil temp comparissions would be very useful in sorting out the rumor from the truth.

bliffle

Nothing that's been reported proves that either the beehive allows excessive oil temp or that high oil temp ruins the engine. All the theories are just that: theories. It could be that the beehive is a perfectly good oil cooler. It could be that high temps are never achieved. It could be that the engine survives high oil temp. As for 12A engine deterioration, it could be inferior oil, or drivers that overrev the puny OEM 12A to try for better performance, or 12A failure is statistically insignificant.

So I'm going to find out with a simple experiment what the oil temps are in my various rotaries with various oil coolers. Since I can't get an RF system I'll use a simple electrical temp gauge moved from one to another as I see fit. I've ordered an adapter to fit between the pedestal and the filter, with a 1/8" NPT fitting, that I can easily install/uninstall. What I need now is a decent electrical oil temp sensor/gauge that is repeatable and fairly accurate.
I see several makes on eBay and was thinking of the OBX unit because of the white face and relatively well-spaced temp ticks. Any better ideas?

trochoid

iTrader: (6)

If you are going to test oil temps, it would be more scientific and accurate if you could take a temp reading precooler and aftercooler on each model. This would require 2 gauges running concurrently. If you could do that, it would be great.

Frostycrowd

iTrader: (9)

I have heard a downside of putting a fmoc on is that the oil wont get warm enough, which is also bad for an engine. So there are downsides, but Im sure just letting an engine warm up properly would fix that problem. Putting a thermostat on would be quite complicated.

bliffle

IMO the engine operating temp should be stabilized to reduce expansion/contraction cycles and the effects of differential expansion rates, both of which cause the engine to adapt to dimensional changes by wearing off the high spots, which in turn creates new high spots in the next expansion or contraction. Thus, one ought not remove the Tstat, which would encourage larger more frequent op temp changes. The exception is race cars that are always operating at high temp. Thus, too low an oil temp is also unfavorable. The oil should be stabilized, not just cooled.

Frostycrowd

iTrader: (9)

well I dont really understand where the t-stat is. If I change coolers is it still in there somewhere? I bought a fmoc and plan to install it but have no idea where the t-stat is, and by removing the behive if it will remove that.

Frostycrowd

iTrader: (9)

oh and what do people do when they remove the beehive. do they just reroute the coolant lines that run through it? I looked at the write ups but they didnt mention that

Midwest 7's

iTrader: (4)

the engine has an oil inlet and outlet to the cooler, whatever it is.
the beehive is junk, just get a front mount and the lines and your good to go~!

Frostycrowd

iTrader: (9)

ok I did read well. I just now saw that fmoc's have oil t-stats in them.. Thanks for all the help

Hades12

The coolent lines

the out stick on the engine has to ports, one still needs to go to the heater core, the other can be blocked off.