Flamethrower Distributor

[frankfast]

Trying to install a Flamethrower Distributor. I can only get it a 1/4" from bottoming out. The dogs seems to be engaged because the rotor doesn't turn. The Flamethrower has an o-ring whereas the original doesn't. I've taken all the measurements and the shafts are the same size and length. Any tricks?

[poolboy]

If this were a TR6, I'd suggest that the distributor drive gear dog is not seated into the oil pump shaft, but I don't if your early TR has the same set up...

[bobhustead]

Loosen the end bolts that hold the clamp to the block and make sure the clamp bolt is loose and the is clamp spread enough to receive the dist body.
Bob

[frankfast]

Loosen the end bolts that hold the clamp to the block and make sure the clamp bolt is loose and the is clamp spread enough to receive the dist body.
Bob

I had the clamp snugged slightly on the distributer before I set the shaft into the hole.

[TR3driver]

I'm with Ken, sounds like the drive shaft is not engaged into the oil pump. It may have gotten lifted when taking the old distributor out.

Also, the distributor drive dog only fits one way, but might hang up if you have it turned 180 degrees.

[frankfast]

On the Flamethrower does the advance unit face the front as on the original?

[frankfast]

Also, the distributor drive dog only fits one way, but might hang up if you have it turned 180 degrees.[/QUOTE]

Why does the distributor drive dog fit only one way if everything at the bottom of the distributor shaft looks symmetrical? Also, when taking out the old distributor the rotor was pointing toward the terminal of "1 cylinder on the cap with the pointer on the engine case lined up with the mark on the pulley (compression stroke right?). The old distributor will only drop in one way, not 180 degrees out. AS WILL THE NEW FLAMETROWER!! The only question is that the rotor on the Flamethrower is pointed in the opposite direction. In other words 180 degrees opposite. Is that all relative since it relies on the orientation of the cap and wiring to the spark plugs? The caps are different.

[TR3driver]

If you look closely at the dog, it is not symmetrical. The blades are slightly offset to one side, and so (of course) is the slot they fit into.
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Since the distributor only turns once for every two rotations of the crankshaft, the mark on the crankshaft pulley cannot tell you if #1 is between compression and power; or between exhaust and intake. If the rocker cover is off, it's easy to tell by looking at the valves (both valves will be fully closed during compression and power). Another is to hold your finger on the plug hole while you turn the engine. The compression stroke will force air out the plug hole and lift your finger, but exhaust won't.

Kind of sounds like your old distributor got assembled wrong somewhere along the way, and someone compensated by turning the drive gear. You can, if you want, compound the error by changing the wiring to the spark plugs. But my preference would be to move the gear instead (assuming the problem isn't that the new distributor is assembled off by 180 degrees).

[frankfast]

You're right I've noticed that the dog is not symmetrical. I've also noticed that according to your illustration and the manual there looks like there is a small keyway in the gear that the distributer dogs fit into. That keyway is 180 degrees offset from the illustration but the original location of the rotor pointed to the first cylinder terminal on the cap with pointer pointing to the mark on the pulley. If the rotor is pointing to #1 cylinder and the pulley mark is at the pointer, is that the compression stroke or could it be 180 degrees from where it should be? If I am on the compression stroke then the gear or distributer is assembled incorrectly. Also, does the crank rotate clockwise when facing the motor?

[TR3driver]

Another possibility (from your description) is that the distributor cap was previous rewired to compensate for the gear being turned wrong. But if the engine ran, and the rotor pointed to the terminal that was actually connected to #1, and the engine has not been turned since then; it pretty much has to be #1 on compression.

BTW, the illustration above is from the workshop manual.

Just to show the strange things that can happen, my Dad's TR3A had the gear turned wrong and the wires moved to compensate when he/I bought it. (I found the car, Dad paid for it.) We went for many years with it wrong, never noticed there was a problem. Then I found another TR3A and bought it for myself. Trying to make it run, one of the first things I did was move the "known good" cap & wires from Dad's car. (The ones on my car were extremely ratty, with big cracks in the insulation and so on.) My buddy and I spent two whole days in the snow and cold trying to get my TR3A to run. (It was basically abandoned in the back yard of an empty house, we were hoping to make it run to get it home.) Finally gave up and towed it home on a rope, then spent another day trying to figure out why the $&! engine would fire but not run. Finally the light dawned and I stuck the old cap & wires back on; it of course fired up promptly.

[frankfast]

The thing that has me stumped aside from the slot being 180 degrees in the wrong direction, the rotors on the new and old distributors are 180 degrees apart when they set in the slot. I guess that if #1 cylinder is at TDC on the compression stroke it doesn't matter which way the slot is as long as you wire the distributor to fire on the #1 cylinder. The caps are very different.

[TR3driver]

That could be what I said before, about your old distributor being assembled wrong.

Also possible Pertronix got the new one wrong. You certainly wouldn't be the first to find a new part that is defective or simply doesn't fit right.

[charleyf]

I have not seen any description of the "old" distributor.

[frankfast]

With #1 cylinder on the compression stroke (both valves closed and pointer on the pulley mark) the rotor was pointing toward #1 cylinder. The cap was a Lucas item with side entry for the wires. The #1 terminal is at the top left. Remember that the slot at the bottom of the distributor is 180 degrees from that shown in the illustration. The rotor on the new Flamethrower distributor is 180 degrees from the rotor on the original (pointing away from #1 cylinder) and that cap has top entry for the wires.

[frankfast]

I don't understand how my original distributer fits into the slot with the rotor pointing toward the #1 cylinder at TDC on the compression stroke when the slot that the distributor dogs fit into is 180 degrees from where it should be.

[charleyf]

Not all distributors are built the same. I recently bought a new electronic distributor for a TR4 that I was building. So when it came time to set up the new distributor and the new timing chain it was installed with the rotor pointing to the #1 cylinder. This new distributor had a different cap from the traditional Lucas distributors that are found on the TR's. I did not think to much about this UNTIL my new electronic distributor died on me about 18 months later. I then dropped an old Lucas points distributor into the engine and found that my dead electronic distributor had been built 180 degrees off from the traditional Lucas distributors. To get me back on the road at the time ( I was about 150 miles from home) I had to rewire the old Lucas cap to accommodate the 180 degree difference. You need to look at your old distributor alongside your new one and determine if the bottom dogs are opposite. It sounds like they are. I could be wrong here but I suspected that the MG may well use a distributor 180 degrees from our TR's. They both work but are just set up different from the start.

[frankfast]

The dogs on my electronic distributor is off 180 degrees from the original distributor and the rotor on the electronic distributor would point to the #1 cylinder at TDC on the compression stroke if the slot the distributor fits into was correct. I don't think it matters if I wire the new cap correctly. Still I don't understand why the rotor on the old distributor points toward the #1 cylinder at TDC on the compression stroke when the slot is off 180 degrees. I want to confirm that none of this matters if I wire the new Flamethrower cap so that the #1 cylinder fires at TDC on the compression stroke regardless where the rotor is pointing.

[TexasKnucklehead]

The orientation "180 off" is arbitrary. It can be "180 off" (or "corrected") numerous ways. I have attached a picture of two "original" Lucas distributors mostly taken apart. The part on top (the top hat) where the rotor would fit, or the part on the bottom that engages with the drive gear, can be rotated 180. I have circled the top with red, the bottom with yellow, but either color is equally incorrect. -Both could be rotated 180, and then it would be off by 360, or 0 depending on how you want to look at it.

[frankfast]

That pretty much answers the question. Since I've never taken apart a Lucas distributor I thought the dogs at the bottom and the top of the shaft that the rotor fits on were fixed. I didn't know that they could be rotated. So even if the slot into which the distributor dogs engage was off 180 degrees the rotor could still be directed at the #1 cylinder which I always thought was correct.

Again, I don't think that it matters that the rotor on The Flamethrower distributor points away from the #1 cylinder at TDC on the compression stroke as long as it's pointing to the terminal that carries the wire to that cylinder.