distributor out of whack?

[NutmegCT]

As a *general* question, if you think your distributor might have been installed 180 off (engine running problems, but good spark) ...

... could you do a quick test by just moving the distributor plug wires clockwise 180 degrees?

Four cylinders, four wires, but plug wires shifted halfway around the clock?

Thanks.
Tom

 

[TomMull]

Since (at least on the TR3,4 etc.,) the drive slot is not on center, I think the geometry of the thing will get out of whack and throw off the timing. Might be able to get it to run that way but probably not by simply moving the wires. Best way to check is to remove the distributor and align the slot per the service manual. Tom

 

[Andrew Mace]

I really don't see how it could run at all if 180 out. But yes, wires can be moved around if necessary to compensate for a distributor installed "incorrectly"!

 

[TR4nut]

Tom-

If you are 180 out, your engine won't run - voice of experience on that one, as I accidently set up the distributor 180 out when I rebuilt my 3A engine. But yes, as Andy notes, no problem reorganizing the wires if it is the problem: 1-3-4-2 just gets reset to 4-2-1-3 and in my case the engine fired right up!

 

[Billm]

It is REALLY easy to set-up the distributor backwards if/when you rebuild it! The upper plate that is controlled by the flyweights can easily be installed backwards unless you are careful and KNOW which way it is supposed to go.
If it is backwards just pull out two cap wires that are opposite and swap them and then do the same thing for the other two, this way is easier than trying to pull them all out and then put them back correctly.
BillM

 

[TR3driver]

Just to echo what Andy and Randy said, if the timing is 180 off then it simply will not start. On the rare occasion when you can get a cylinder to fire, it will simply blow out through the carbs and not turn the engine. BTDT, got the burns to prove it.

But swapping the wires will solve the problem. Drove that way for years without even realizing it had been done. The problems started when I foolishly moved that cap & wires to another TR3A motor that hadn't been assembled wrong, and then tried to start it.

 

[NutmegCT]

Thanks gentlemen. I'd read somewhere here (before the update) about swapping wires as a test, but wasn't sure.
Tom

 

[Geo Hahn]

If it will not run at all and you're thinking of trying the 180° switch to see it that is the problem then that may work out for you -- but seems simpler and surer to just look at where the rotor is pointing when #1 is at TDC. Should be pointing (roughly) at the #1 spark plug.

 

[NutmegCT]

If it will not run at all and you're thinking of trying the 180° switch to see it that is the problem then that may work out for you -- but seems simpler and surer to just look at where the rotor is pointing when #1 is at TDC. Should be pointing (roughly) at the #1 spark plug.

Thanks. Just so I understand, at TDC, if the distributor cap were a clock, the rotor should be pointing to #1 spark plug (about 1pm)? or to distributor contact point for #1 spark plug (about 4pm)?
T.

 

[Geo Hahn]

...or to distributor contact point for #1 spark plug (about 4pm)?

Hmmm. You're saying that the connection on your distributor for the igntion wire that goes to #1 is at 4:00?

On mine the distributor connection for # 1 is in the same direction as the rotor pointing to number one:

I am not clear on whether your engine currently runs or if you are trying to get it to run. If the latter then possibly the wires are simple misplaced.

 

[TR3driver]

but seems simpler and surer to just look at where the rotor is pointing when #1 is at TDC. Should be pointing (roughly) at the #1 spark plug.

Just be sure that #1 is at TDC between compression and power strokes; rather than TDC between intake and exhaust stroke. #4 is supposed to fire when #1 is at TDC between intake and exhaust.