MSD spark advance question

[Wayne Maybury]

I have noticed recently that on occasion my 351W cranks very slowly when hot. It sounds like there is too much advance but the timing is correct. I took the cap off of my MSD distributor to check things out and found that the mechanical advance sticks just before going back fully. I had one very small spring and one larger spring on it so I replaced the small spring with a larger one. Same thing; the advance seems to stick always at the same point. I just nudge it and it goes all the way to the fully retarded position.

Is there some way to lub this? Am I missing something? Two large springs will not bring the advance back all the way. Any ideas?

Wayne

[Ralphy]

Seems I heard someone else with this problem recently. MSD would recommend sending it in.

http://www.msdignition.com/forum/showthread.php?t=9822

[bobcowan]

I would pull out the palte, and disassemble it. Polish all the parts. Put it together dry, and try again. Mass produced metal parts often have little burrs and areas of roughness that keeps them from moving properly.

Most wet lubes will attaract dirt and grime. Over time, they'll dry up and turn to varnish. You could use a little dry powder graphite, but it won't stay there long.

[Ralphy]

Carefull with graphite, it's a great conductor. I also would look for hanging parts however.

[zrayr]

under the advance weights there should be two round plastic pads which are there to help reduce "sticktion". They will wear and break off. I would make sure they are still there before you look elsewhere for the culprit.

Z.

[Wayne Maybury]

Thanks for the replies. I will look to see if the round plastic pads are still there. So far all I have done is increase the spring size.

I will let you know what I find.

Wayne

[CJ428CJ]

Don't forget that changing those springs will also change your advance curve. Go here: http://apps.msdignition.com/pdf/8577-8579_frm17088.pdf

After you get your sticking problem resolved, you may want to go back to the lighter springs.

Chris

[Wayne Maybury]

Originally Posted by CJ428CJ

Don't forget that changing those springs will also change your advance curve. Go here: http://apps.msdignition.com/pdf/8577-8579_frm17088.pdf

After you get your sticking problem resolved, you may want to go back to the lighter springs.

Chris

Thanks Chris. I realize that I am changing the advance curve but at this point I am just trying to get the advance to go completely back to the rest position. I will worry about the curve later.

Wayne

[mkassab]

you have one other option based on what I've read (havn't done it yet, but bought the unit)..... buy the 6AL2 programable, and you don't use any springs and lock down the mechanical advance. The 6AL2 Prog. does all the advancing per the input via a PC link that comes with it. No Moving parts this way.. all done "digitally"
Good luck, Mark

Here's a quote from the MSD 6AL2 Prog. web page
"The new ignition, Part Number 6530, is based on the same output as the 6AL-2, but rather than rotary dials for rpm adjustments it sports a serial port that connects to a PC. Once you load MSD’s Windows based software on your PC, you’re ready to start mapping and programming. To start, you can get rid of the weights and springs that control the mechanical advance of your distributor. Go ahead and lock it out because you can now create a timing curve that allows you to manipulate the timing down to tenth of a degree increments every 100 rpm. The advantage is precise timing control, with the ability to ramp the timing in or retard it at exactly the rpm that you want it to move. Want more timing out for a start retard? Simply click the mouse and move a couple dots in position. Like a high speed retard? Clickity-click!
"