Friday, April 27, 2018

Cap and Rotor Time

Since one of the priorities in this project is to take care of deferred maintenance items, I thought I'd start with the ignition system. It's easy to get at, and relatively easy to work on.

The cap is held on by three hex head screws that also have a full-width slot, and a Phillips head drive. I have no idea when the cap was last changed, but holy smokes were the screws ever tight. I tried a Phillips head, and could only get the top one loose, so then I tried a big flat blade. Barely any better, so I got out an 8mm nut driver. No dice, couldn't get a decent grip on the handle, so I broke out the 1/4" drive socket set, and busted the other two screws loose.

And then I had to get out a soft hammer, and tap the cap to get it loose from the distributor housing.

The cap isn't the worst one I've seen (or used..), but it was really stuck on the housing by some corrosion.

The inside of the housing is fairly clean, and I'll be really gentle cleaning it, as these things are a bit delicate, and expensive to replace. You can see the corrosion on the right side of the housing. There are two "Reluctor Pickups" in this distributor. The one with two "lobes" tells the Engine Control Computer that the crank has made one revolution, and the one deeper inside with all the teeth gives the ECC much more precise information.

NEVER disturb the pick-up coils or the spacing to the teeth unless you know what you're doing and have the shop manual.

And the hold down clamp doesn't look like it's ever been loosened.

The rotor looks really weird, and I can't recall ever seeing one with this pattern of discoloration on it. It's all mottled and a bit 'sooty' looking, but shows no signs of cracks or carbon tracking, and the car idled as smooth as silk. The parts are pretty dirty and worn, but they were still working. Just gotta love that Toyota reliability, although I'm sure WSF might disagree.

I think it's made of the carbon button contact in the cap, and other "stuff" like oil vapor and humidity that gets in through the vented cap. There's a baffle on the outside of the cap that covers the vent hole, but stuff still gets in, and over time, it looks like a lot got in.

I have no idea when the cap and rotor were last changed. I put a new set of plugs in her the first time it failed smog, but that's all I did to the ignition system.

Looking at the plug wires reveals a manufacturing date code of 2003, 15 years ago.

Looks like I'm off to Rock Auto to order a set of plug wires, as nobody local carries them.

I might very well have the only functional, road-worthy MKII Supra in the area.


  1. I do respect Toyota reliability. Just wish they were cheaper to fix. As an aside, you have one of three models of Toyotas I would have owned, back in the day.

  2. Cheaper as far as parts cost or dealership labor rates? Some of the parts (when you can get them) are stupid expensive from Toyota, which also drives up the price of functional used parts.

    For normal wear items I go to O'Reilly or Rock Auto. For soft items like trim, its used parts, custom fab, or nothing....

    What were the other two Toyotas you thought of back then?

  3. Early Cressida with the I-6. Original Land Cruiser. I rather fancied the MR2 but could not fit. Once had to drive a trade over to the Toyota store. The side bolster were so narrow I couldn't get my back against the seat. Plus it was a stick shift. The sight of my driving up put the store out of business for a few minutes until they could all stop laughing.

    1. The whole point of selling used cars is making money. My focus was on rapid turnover and minimal "front line ready" costs. Pickups were a focus. A secondary, but serious, focus was on the financing picture.

      Trade ins were accepted, whatever the make and condition, if the transaction made sense. I rarely went to the dog show, aka auction. Wholesaler vehicles were viewed with great skepticism.

    2. MR2's are pretty small cars. I had a Fiat X1/9 back when I first moved to Kommiefornia, and always wanted a MR2.

      And a Supra, of course!

  4. You knew your market, and what would and wouldn't work. And I'm sure the auto market here is very different from the market in the Chicago area, which is what I knew.

    I always found it "interesting" to watch the fortunes of the independent used car dealers in town. Some were really good guys, honest and truthful, while others stopped just short of being out-and-out crooks. You rooted for the good guys, and sent business their way when you could, and despised the crooks. I'm sure that part of it is still the same, both here and back in Chicago.

    My friends at the franchised dealerships would only keep the cream puff trade-ins, and the rest went either to a local independent, or the Greater Chicago Area Auto Auction, which was a whole world unto itself.

    The Cressida's were nice cars. These days I tend to think of them as "Four Door Supras" after I learned how much of the Supra came from the Cressida.

    The 2.8L 5M engine is a good engine if taken care of. Regular oil and filter changes of course, and other maintenance "per the book".

    1. Colorado is somewhat unique in licensing dealers and salespeople. There is a dealer board that can, and often does, pull licenses. Cuts down on outright crooks and felons.

    2. I'm pretty sure there was something similar in Illinois back then. I know the dealerships had to be licensed, but salespeople? Not that I ever remembered.....

    3. CA had licenses for vehicle salesmen at least back to '78, as I had to get it to work at a bike dealer as the backup for the owner. Had to go to DMV, just like a driver's license.

  5. Sounds like scrounging parts is going to be an ongoing 'thing'... sigh

    1. Depends on what the part is. Items like major interior trim pieces are unobtainium from Toyota, and have been for decades. You can still get some little things like knobs, but they're drying up. I suspect a lot of people like me are buying up anything and everything that can still be had.

      Normal wear items are also readily available from a number of sources. It's just that none of the major parts places here have anything other than stuff like oil filters and spark plugs. Need an air cleaner? Sorry, have to order it!

      At least it's getting me back into planning and budgeting for the parts I need.

    2. If you decide to replace that cap, try to find it with brass contacts, instead of the cheaper, common aluminum. Some ignition brands had a two tier supply setup, cheap and premium, and that was one of the differences.

    3. The cap was destined for replacement ASAP. It's an "unknown" item on the maintenance list that needs to be cleared.

      I ordered two caps from Rock Auto quite a while ago. They came in identical "KEM" boxes with identical part numbers. One looked identical to the Nippondenso cap that was on the engine; black plastic with aluminum terminals, "Made In Japan" molded on the inside. The other was the red "alkyd" plastic with brass terminals, prominently stamped "Made In Italy", and looked identical to what we considered the "good" or "High Performance" caps I used to get back when I had a part time gig working on funny little furrin cars. Reminded me of the parts I'd get in a Beck-Arnley "WorldParts" box; if you bought four caps, you'd get three vendors.

      So you betcha, the red one went on the car tonight.

  6. Suggestion:

    Never seize or Strike-Hold on the threads of those fasteners...and on the shaft and other stuff that is rusty (after you clean 'em with a wire brush) A bit of silicone heat sink grease on the edge of the cap works to prevent (but not stop) corrosion at that point.

    1. Were you watching over my shoulder last night?

      Yep. I ran a rethreading tap through the holes to clean the grunge out, and put a dab of anti-seize on the threads of the new screws in the cap.

      And I put a bit of silicone dielectric grease on the edge of the cap so it won't freeze on there again.


Keep it civil, please....