Deleting oil cooler

(David Culgan) #1

1986 XJ-6 series III

I’m interested in running without the oil cooler. it appears that the procedure involves removing the bypass valve in the (EAC 2425) filter head, located behind a large slotted head screw and then plugging the ports for the oil lines . I saw a reference to ¾” copper pipe caps, but I didn’t understand if the (CAC 5118) o-rings and the OEM bar clamp and fasteners were used, or something more like adhesive. The later model engines seem to have a u shape casting available just for deleting the oil cooler, is there something similar for the XJ engine? I’d rather not cut my lines up to fabricate a short bypass line but I guess that would be another way. Sourcing an earlier, non oil cooler, (EAC 3144) filter head would be best but I’ve been unable to find one advertised for sale anywhere. Anyone remove their oil cooler? How did you do it. Thanks, Dave C.

(Paul M. Novak) #2


Why are you interested in getting rid of the oil cooler? How would that provide any benefit?

One reason I ask this is because a prior owner of my 1987 XJ6 VdP disabled the oil cooler by cutting the two hoses, inserting a bent piece of copper water pipe between the cut hoses, and adding hose clamps to prevent oil leakage. I never understood why that was done. Two new hoses and o-rings easily returned it to its original leak free operation.


(David Culgan) #3

No real benefit. It’s all apart right now, I’ll need two new lines as the old ones were leaking when the car was last running, and at this stage I wasn’t sure I had the budget for two new lines. If it was easy to bypass and remove the equipment for now I was considering that option. Dave

(Robin O'Connor) #4

One advantage that I found with the XJ40 was that the oil did not get contaminated with the old oil contained in the cooler and lines when performing an oil change.

(Robert Wilkinson) #5

That reference might well be from me. I can’t remember for sure what I used for gaskets. I fit the pipe caps top down. I think I cut some gasket material to place under the cap. I was afraid that O-rings, not confined to a groove, might “sag” and cause a leak; the gasket material is stiffer. I may have used some fibre washers instead–same idea as gasket material. Yes, I used the OEM bar clamp and fasteners.

I’ve never heard back if anyone else has confirmed that this works in the long term. It has for me, but I’m just one data point.