Distributor Drive Gear

[MoHealey]

Just completed installing rebuilt engine in my '69 GT.
When I tried to drop in the distributor, it became obvious that I would have to rotate the dog 180 degrees from the position it was in when the motor left for the machine shop.
I did that, and the motor starts and runs fine at an idle (just timing to ear at this point).
Question is; is it even possible to install the drive gear "backwards"? Is there something really simple that has escaped me?
Any help appreciated.
Thanks

 

[ralph_s]

The drive gear on the dizzy is "keyed" and will only fit in one way. It is possible to put in the dizzy drive spindle 180 deg out out of time, but the car won't start. You should be correct, but will need to fine tune your timing.
You only mentioned the car runs at idle? Also at higher RPM?

 

[DrEntropy]

The gear from cam to dizzy is easily dropped in in the "wrong" position if you aren't familiar with the alignment procedure. You can reposition it by removing the dizzy, clamp and the spacer/collar. Ascertain TDC #1 firing, the off-center slot in the jackshaft driving the dizzy should be in about a 2 O'clock/8 O'clock orientation (straight up being 12 O'clock) with the larger part of the offset to the top. There's a threaded hole in the center of the jackshaft which allows easy withdrawl and insertion using a long 5/16" NF bolt as a tool. I'm not so certain of the bolt size/pitch but a headbolt works, I know that. :wink:

 

[MoHealey]

Was afraid to push any revs, but have since. Overall, the timing is clearly correct, but it sounds like I may be losing a cylinder intermittently at about 2000. By the way, I bought a new Pertronics dizzy for the rebuild, and I had to flip the dog on it right out of the box. I've had many of them, and never had this happen.
Are you saying that if the drive spindle is 180 out, it's impossible to compensate for it if I have essentially taken the dizzy 180 the other way?

 

[DrEntropy]

Just "juggle" the wires in the cap! 1-3-4-2 is all the spark knows or the pistons care about...

I've run across a lot of DIY rebuilds with the drive gear in all sorts of positions. Usually 180 out, and being "practical"(read lazy), just swapped the wires, static timed and lit 'em up.

 

[MoHealey]

Is suppose you are right.
Trying to overthink this.
But as for the DIY aspect - Fully realizing my own lack of skills (and time) I paid good money to get it done right!
Already discovered a malformed oil pressure relief valve was re-installed.
Swapping that immediately after startup is not helping my mood.
Confidence is low.
Thanks

 

[DrEntropy]

That is a BEAR of a task with the block in the car!!!

 

[MoHealey]

Tell me about it! Almost laughable now (as I bandage my wounds).
I and my assistant (my son) used a unique combination of 1" socket and two wooden measuring sticks against the inner fender to apply posititve pressure to the back of the ratchet so as to compress the spring.
Made a note to myself. Self - never again shall you fail to double check the condition of the oil pressure valve prior to installing an engine.

 

[DrEntropy]

It ain't that easy even on a stand. First time I did it, it was out of naiveté, some time around 1969... took hours and me Ol' Fella as helper to get that spring back in and threads started.

We had a cold beer after. And I never again had one out unless the block was on a stand.

 

[Silverghost]

This sounds like the automotive equivalent of a colonoscopy?!

 

[DrEntropy]

Near enuff!