MSD DISTRIBUTOR buzzing

[madmaxx]

Well I reinstalled the distributor, it fired right up. With my $800 ultrasonic listening device I could not determine anything, to sensitive LOL!!! I did find the source of the noise however, once again persistance pays off. The noise occurs between 850 and 870rpm. At that speed the centrifugal weights resonate, if you go above 870 rpm they are quite or below 850 rpm at 860 rpm the noise is constant. I suspected they could be the source when handling the distributor they rattle like a box of marbles when just spinning the distributor by hand. Springs are there, bushings are there, just loose fit by design.

It makes sense I just now noticed the noise. Now that it cold and getting dark early I bumped the idle so that when the headlights, heater and coolant fans kick on the idle doesnt drop to low I bumped the idle up a couple weeks ago just when the noise started to appear.

In the end it was not a bearing, not electrical noise etc. It was "looseness" in the weights pivots".

Thanks for the all the help.


I did find my wind leak on the lexus. The tone generator is cool, you cannot hear it with out the listening device and ear muffs. Turned out not to be the window but the door seal by the front fender, took about 2 mintues to find. Every tool has it place.

[patrickt]

See? I told you to just ignore it.

[zrayr]

by any chance are you missing the plastic pads that the weights move across as they swing in & out ?

Z.

[madmaxx]

Wow, you know your distributors!! I did see the pads and although polished, definelty not worn. I guess the beauty of an MSD is the distirbutor is painfully simple. Shaft, bearing, weights, springs, mag pickup. When try to identify my noise I kinda lost confidence in MSD with all the issues I read about not that I have ever had one that would cause the engine not to run.

In the end it was nothing to worry about, but it seams for every 10 I waste my time hunting down, 1 would have really biten me if I did not catch it early.

Now onto my valve cover gasket leak. I am about to the point of using permatex ultra black on both sides of the gasket and be done with it. Gasagacinch? may be good for intake manifold gaskets but useless for valve cover gaskets.


The other problem I solved this week was with my wife's Envoy. It has been a flawless vehicle for 8 years but lately the engine was vibrating everything including the steering wheel, grill, doors, dashboard contents. It was horrible until the car warmed or I you put it in neutral. I was about to trade it in after reading all the nightmare stories on trailvoy forum about the $1,000s of dollars people spent trying to address the same issue and never solved it. I finally stumbled across 1 post, incredibly enough it turned out to be the motor mounts. I replaced them and the car is like new, it is so smooth. I also determined the mounts had to be GM aftermarket dont work. The mounts are fluid filled and apparently over time the bladder looses it elasticy and they become "solid". So digest that, gm doesnt make a smooth engine they just compensate with motor mounts!!!

Originally Posted by zrayr

by any chance are you missing the plastic pads that the weights move across as they swing in & out ?

Z.

[patrickt]

Originally Posted by madmaxx

Now onto my valve cover gasket leak. I am about to the point of using permatex ultra black on both sides of the gasket and be done with it. Gasagacinch? may be good for intake manifold gaskets but useless for valve cover gaskets.

Max, before you go to that extreme, do yourself a favor and try Open Gear grease -- it seals the gaskets down without "glueing" them there permanently. Half way down on this thread is a pic of the stuff I use. Motorcraft FL-1hp pressure drop

[madmaxx]

Too funny and thanks, I have a jar of 1122 sitting on my desk. Since I work in a petrochemical plant I have access to about every lubricant and chemical in the world. I'll give it a try. I use the rubber caskets on my valve covers which worked great until I yanked them off one time, now I got a weap on the back side of the driver side valve cover. I tighten the valve cover bolts it goes away for about 2 weeks and then comes back, the gasket continually relaxes but is much better than the cork I used to use.

[patrickt]

What I really like about the 1122 is that if the kids are bugging me I just wave the jar under their noses and then they sit quietly in front of the TV for hours and don't say a word.