I recently purchased a C-type replica with a MK2 3.8 engine. The oil filter assembly was missing. I have a spare late 3.8 Mk2 assembly as well as a 4.2 E-type assembly. The engine block has four mounting holes as does the E-type housing. Will this work with the 3.8 Block? The Mk2 canister I have interferes with the frame rails so will not work, as well as having a fifth mounting bolt.
Unless there is an oil flow problem the only problem I see is the filter bypass hose is at an odd angle to the Mk2 oil pan.
A lot of amateur and some pro know-it-alls get in trouble mismatching parts.
That slotted head screw that is blocking the small oil port is there because the original filter head had a bypass hose to the sump.
I think I see another plug in the lower right port, where also oil dumps back into the sump.
The idea is that when the pump is putting out more oil than the main bearings can take, the bypass valve opens and the rest gets dumped back into the sump.
You want to check your flow routing is in accordance with this diagram.
The slotted screw (there’s only one) serves as the gallery plug for that bearing. It’s actually a flush plug so that the filter head can seal to the block, and need not be removed. You can see the full row of plugs running along the right side of the engine. These are there because Jaguar needed access holes to machine a passage between each bearing and the main oil gallery. Once the block was finished, the gallery plugs, including the slotted screw, seal the access holes. Judging by the witness marks on the block, the original filter head had some “dead space”, where that flush plug is located.
The overpressure valve that’s in every XK filter head of any style simply opens the outlet to the sump when pressure exceeds 55 lbs. There’s also a bypass valve that allows the inlet and outlet port to short circuit if the filter element clogs, this is the hex plug you see on the bottom of the E-Type head and on the top of the MK 2 head. XK filter heads generally interchange, but there are a few gotchas, like this one with five mounting bolts. Some have extra ports for sensors and switches, and the later ones have provisions for oil coolers. The E-Type head seems to be a perfectly good choice for this engine.
You need to be careful with that block. The large hole on the bottom right is the bypass for the early filter heads that did not have an external hose that directed excess pressure back to the sump. Later blocks (shown, one from 1964) omitted it. It goes directly into the sump.
Bottom left is unfiltered oil from the oil pump, top center is filtered oil to the main oil galley.
As was pointed out, the 1/2"-20 threaded plug blocks the drilling from the block exterior through the main galley to the center main bearing. Not all blocks have this plug, as some rely on the configuration of the filter head to block it.
This is what my 4.2 block looks like that the E-type filter housing came off off. So should I plug the lower right hole in my 3.8 block to use the E-type housing? See the first pic in my original post.
Ah yes, you are correct! I didn’t see it before. I checked this morning and there is indeed a cup type plug in that hole. I will order the correct gasket and bolt it together. This is one more item off the list of things to figure out about how to build this car.
