Putting the Oil Cooler back on a motor, and in reading from a Hayes manual, it states to be sure and put the washer next to the crankcase. Could not find anything about the topic in the factory manuals. Based on the parts diagrams I have, it only shows the two on the outside next to the nut. (1-thick flat washer next to cooler, then 1-wave washer next to nut). So is there a thin flat washer that goes between the crankcase and the oil cooler?

Also, I have never done anything other than tighten the nuts down to the point that it snugs up the the two rubber seals. Is there a best practice here, since
the is not a torque setting?

Thanks!

Case-OilCooler-ThickFlatWasher-WaveWasher-Nut

Nothing between the case and the cooler.

Some T1s with some kinds of seals used a washer between the cooler and the case, no T4 does.

The Cap'n

Thanks! Got it!