Bottom End? or just balancer?

[Krafty]

my 79 bird with the 69 429 has slowly developed a nasty vibration between idle and 2500 rpm over the last year, above that it goes away. can't tell but it may or may not get worse when under load. my money is on worse.

I have checked again and again and I don't think I have a bottom end knock, just the vibration and the noises it causes from my passanger side exhaust pipe hitting the tranny mount, and the custom bracket for the automatic shift cable tapping the drivers side floor, I can isolate those noises and I don't hear anything else.

the other day I decided to take action and check and tighten anything I could find, I found

- loose motor mount, loose tranny mount, 2 of 4 tc nuts were 1/2 to 1/4 turn loose, my one exhaust pipe was loose, and I have a ujoint going bad.

tightened everything up and fixed everything except the ujoint, and it still vibrates like a MF.

if you watch the crank shaft pulley you can see that it wobbles quite a bit in the danger zone, run it up to 2500 rpm or higher and it smooths right out, then if rpms drop and the wobble comes back.

here is my question. is it heaven forbid motor overhaul time? ( I can't afford) or would the right fix be a new balancer? which I can afford.

tell me what you guys think before I spend any money on parts.

 

[Bully Bob]

Hi Krafty..,

It's been found that H balancers can split & seperate...usually it can't be seen, however it can "rotate" on the outer ring thereby, throwing it out of bal.

My neighbor had much of his eng. front appart B/4 I walked over there...I instantly spotted his...the outer ring was cocked at about 10 deg. It was a lucky scan but it would have flown off in a couple more hrs. of driving anyway.

Knocking fr. a bad bearing would be obvious...especially under load.

As to a front main bearing.., I don't know...this could be a culprit and make no noise...

Lets hope it's the bal. / :-B