[Bb5280]

Originally Posted by ossiblue

Okay, maybe I'm missing something here.

The flow through the Mocal will affect the operation of the thermostat and it disrupts the correct oil flow of the 911 system. Look at the two diagrams I posted showing the Mocal in the closed and open positions. Let's substitute the word "Tank" for the word "Engine" for the destination of the return port. Now, mentally connect the front cooler to the ports as described by the OP.

If the Mocal is plumbed like the OP describes with the return from the cooler connected to the left, lower port, how does the oil get back to the tank when the thermostat is closed? There is no access for the oil to enter the tank through the Mocal internal drillings, from the top right port (where the oil is now stopped) to the bottom right port where the line to the tank is connected. There is no oil flow back into the tank, and, more importantly, there is no oil flow through the thermostat either. Without oil flow through the thermostat, it will take longer for it to warm up and open. As it is plumbed now, the warm up has to come from "radiant" heating of the stationary oil trapped in the body of the thermostat. A factory external thermostat allows oil to flow through it, when closed, and as the flowing oil heats up the thermostat opens.

If plumbed correctly, the Mocal would do the same. Cold oil would by-pass the cooler, but would be circulating through the thermostat all the while. As the circulating oil heats, the thermostat will open sooner and oil will flow to the cooler.

Again, maybe I'm missing something, but the diagram supplied by the OP which shows the return from the cooler entering the "engine" side of the thermostat and exiting to the tank via the "cooler" port, ought to be corrected, IMO.

I have to agree with you - I wasn't sure if the MOCAL did something different or not - - but it just did not look right to me - had an engine failure and was looking at the lines and getting new and that setup just looked wrong as I traced it out.