Distributor O-Ring

1) Norm: To start with, turn the engine to top dead center (always do this to pull the distributor). You do that by making sure the “0” timing mark on the pulley lines up with the marker pin. Then look down in the oil filler hole. You should see a dimple in the intake cam. The dimple should be split by the “straight edge” of the oil filler.

2) Unsnap the rubber boot over the distributor and remove the spark plug wires from the distributor.

3) Remove the two 12mm bolts holding the distributor in the engine. Pull out the distributor. It will be a tight fit. You may need to remove the dizzy cap to enable you more room.

4) Norm: You will see the external O-ring on the base of the shaft. It is fairly obvious how to replace it. Just roll it off – then lightly lubricate the new one and roll it back on.

5 ) Now – look inside the distributor where the electrical parts and rotor are. Is it oily, or is it nice and clean. If it’s nice and clean – skip to the reinstall phase, step 12.

6) Norm: If it is not clean – icky with dirty oil and such – the inner O-ring needs to be replaced. You will need to drill, and then drive out the pin that locates the gear on the shaft. I recommend mounting the distributor in a vise and using a drill bit that is bout 1.5 mm smaller in diameter than the pin. Mark the position of the gear on the shaft with a sharpie or a scratch awl. When you have a hole through the center of the pin, or at least about half way through, you can use a drift the size of the pin to drive it out.

Verno: Once you get the pin out remove the gear (you marked it, didn’t you.) then you are set to pull out the shaft.

You may have a hard time getting the gear off the shaft. If this so happens to you, try this suggestion by MACE from the MR2 Owners Club. “I used two open end wrenches to work my drilled gear off the varnished shaft. Put the wrenches like so, and then spread them apart to lever the gear loose.”

7) There are two hold downs (green) that hold the bearing and shaft in place before you can pull out the shaft:

Take out the screws:

These are what they (the hold downs) look like out of the dist. Dirty and gunky huh?

8) Hold the distributor with the cap end facing up (so you pull “up” on the shaft). Make sure when you pull the shaft out that NOTHING gets disturbed on the top end – those little field pickups are VERY picky about where they are.

The following pictures are of the freshly removed shaft and what the now shaftless Dist. looks like inside:

Now before you do anything else make sure you get this stuff from K-Box

9) The pic shows, from left to right, the housing seal, the shaft seal, and an o-ring for the green female connector.

10) Norm: Once the shaft is out, you can roll the inner O-ring off, and then lubricate and roll the new one back on.
Then CAREFULLY reinsert the shaft into the housing. Once the shaft seats, you can replace the gear (align the marks) and drive the roll pin (provided in the kit) in to hold it in place. You are ready to reinstall it.

11) Norm: Make sure the distributor shaft turns freely, and has no excessive free-play. There is a dimple in the distributor shaft (near the pin) and one on the housing..)(Verno: the dimples are aligned in the step #4 pic) Line those marks up. Holding the rotor stationary (very important), turn the distributor to where the rotor is pointing at the ground. Insert the distributor – and still holding the rotor stationary with respect to the housing slide it in. As you do, it will rotate about 60* clockwise. Again, make sure the rotor doesn’t turn with respect to the housing (it will turn with respect to the motor). Once it is in, check to see if the bolt holes line up. If they do, you’re almost done. If they don’t note how much they are off and pull it out and try agian, adjusting for the amount of error. (Note: If you do this part right, you should have no problem starting the engine and re-timing it. In fact, if you mark base with respect to one of the bolts before you loosen it, and line everything back up right, you shouldn’t even have to set the timing.)When you’ve done this insert the bolts and tighten them just past finger tight. Reconnect the electrical plugs.

12) Norm: Look at the bottom of the distributor cap, there should be another large O-ring around the base – where it sits on the distributor. If there is, replace it – if there isn’t put the new one from the kit in there.

13) Norm: Then reinstall the distributor cap (or – it might be a good time to think about replacing it).
Verno: Pic here is with the cap as well as the heatshield installed

14) Norm: Start the car. Time it. Torque the distributor hold-down bolts. Clean up the area and close the engine cover. Have a beer.
Verno: There you go, now that wasn’s so bad.

This documentation in no way replaces the Toyota MR2 Repair Manuals. The purpose of this content is only to provide supplementary information to fellow MR2 enthusiasts. Midship Runabout and its contributing authors will not be held responsible for any injury or damages that may occur as the result of practicing any of the methods or procedures described within this website. Article and photo submissions are property of the contributing author.

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