EJ-DE Spark Plug Tube Seal Replacement

[smallcarsimp]

I’ve removed my valve (rocker) cover and cleaned it using a pressure washer but ended up blowing out one of the Spark Plug Tube Seals.

I’ve seen another thread on here suggesting a very crude way to replace the Spark Plug Tube Seals on the EJ-DE by bending the baffle plate using a screwdriver and hammering it back, but I wasn’t able to force myself to do something so ham-fisted so I enlisted the help of my ex-airplane mechanic father-in-law to make the baffle plate removable.

The valve cover on the EJ-DE uses insert molding to attach the baffle plate to the cover. You can see the rivet-like shapes on the baffle plate. These are not rivets but are pushed through the baffle plate holes when the cover is casted saving material and manufacturing cost.

The steps included:

1. Drilling out the rivet-like shapes to detach the baffle plate using a large drill bit and knocking the remaining material off using a chisel.

   

2. Removing the baffle plate and cleaning the cavity underneath.

3. Drilling 3mm holes where the rivet-like shapes used to be.

   

4. Tapping each hole to M4 size.

   

5. Adding ‘Gasket Maker’ to the veins between the cover cavity and baffle plate.

6. Attaching the baffle plate using M4 screws & washers with lock tight.

   

[evilhighway]

nice write up. Does this stop the oil from getting to the seals so you don’t need to replace them? I know you can use Honda seals as the replacement seals. Cant remember the part number off hand but can I can find out.

[smallcarsimp]

Thanks! This was done so it’s easy to replace the seals when needed as it’s very common for these seals to leak oil into the spark plug cavity and it’s often not replaced because it’s not really replaceable. When they wear out, I can just remove the baffle plate using the screws and press fit new seals into the holes. In fact, I’ll probably keep using this valve cover on all EJ-DE Daihatsu’s going forward.

These engines are shared with the Toyota Duet, so it’s still possible to get replacement parts:
Toyota/Daihatsu 90044-80571

I tried buying via Amayama but ended up having to buy the part through Impex instead as the suppliers on Amayama came back to me saying that they don’t stock it anymore.

[evilhighway]

Yes the Honda part that works is easier to find and probably cheaper. I havent had to do it yet on any ej or efdet I have had but I know there will come a time to do so. Thanks again for the write up and sharing.