Distributer adjusting
Thread Starter
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From: Waterford Mi
Distributer adjusting
Are there different size wieghts for the mechanical advance? I changed the springs but the mech advance even at idol (700 rpm) I had to grind the wieghts down to fix the problem, everything else seems to work fine. Even after I got it to hold back at idol; it does'nt take much to get them to max out again. is this a good thing?
73 L-48,
73 L-48,
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: Distributer adjusting (redwingvette)
Do you have the vacuum advance hooked up, if so it will 'max out' real fast
if you revving it in the driveway. Unhook the vacuum advace and see how it advances.
if you revving it in the driveway. Unhook the vacuum advace and see how it advances.
Thread Starter
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From: Waterford Mi
Re: Distributer adjusting (MotorHead)
Thanks for the reply, No the vacuum was not hooked up as I always set timing with it disconected. It took me awhile to figure out what was happening. I set the engine to 3000 rpm to set the timing and after letting it back to Idol it was still at 36 degress. any suggestions? :confused:
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From: Hoosier
Cruise-In III Veteran
Re: Distributer adjusting (redwingvette)
Sounds like your distributor plate stuck in full advance position. You might have to dismember that thing and investigate why? But usually the idle speed changes when the advance is changed? Hmmmm....you have to pull the cap off and look....that's got to be step one.
Worst case is that the harmonic balancer is out of whack.
Worst case is that the harmonic balancer is out of whack.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: Distributer adjusting (redwingvette)
I think your mechanical advance has seized up from rust. :eek:
Take the cap off and see if yu can advane it by hand.
[Modified by MotorHead, 10:46 PM 10/21/2001]
Take the cap off and see if yu can advane it by hand.
[Modified by MotorHead, 10:46 PM 10/21/2001]
Thread Starter
Safety Car
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From: Waterford Mi
Re: Distributer adjusting (MotorHead)
No rust found. The plate moves free and easy. I have gruond about 1/8th inch off the weights which has allowed the springs to bring the timing back to 22 @700 rpm. ( mechanicals move 14 degree which put me at 36 degrees max without vacuum: Vacuum moves another 15 degrees which puts it at 51degrees total.) the 51 degrees total seems abit to high but, according to the Chilton manual, there are some factory engines set @ 47 degrees so if you add 4 degrees for performance you are there. Any way, I still don't know why I needed to grind down the wieghts but aleast it is working for now. I think I will take it to some one with a distributor machine.
Alwayswave,
(Worst case is that the harmonic balancer is out of whack) Please explane?
Thanks
Brian
Alwayswave,
(Worst case is that the harmonic balancer is out of whack) Please explane?
Thanks
Brian
Racer
Joined: Nov 1999
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From: Lombard IL
Re: Distributer adjusting (redwingvette)
It sounded like your center plate had gotten stuck. Did you disassemble and find nothing wrong? Where did you grind on the weights? When I was working on mine, I found that if the weights went too far, they'd hang on the center plate. Lars, sells a recurve kit that's similar to what you've done, which is reshape the weights/center plate for getting the full mech advance at ~3000 rpm.
You can easily check your dampner by putting a pencil mark or something on both the outside hub and the inside hub. If after some revs they're off, you've got a problem.
You can easily check your dampner by putting a pencil mark or something on both the outside hub and the inside hub. If after some revs they're off, you've got a problem.
Thread Starter
Safety Car
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From: Waterford Mi
Re: Distributer adjusting (Gerry)
I ground off the ends which moves out. If I put my other set back on even with the stiffest springs I have the same issue. I don't see anything that cancause it to stick and after I shut off the engine they seem to go back to the home position. However I do think the main shaft has some unusual whare.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
Re: Distributer adjusting (redwingvette)
This is the setup I have and it works great. I have NO vacuum advance connected and I set my initial timing to 21 degrees. My mechanical distributor advances the timing 15 degrees and at 3000 RPM I have 36 dgrees.
My car has run like a clock for five years with this setup and I see no reason to hook up the vacuum advance.
That being said I cannot figure out how it is supposed to be set up with the vacuum advance. This has been driving me crazy for some time now. This is what I tried, I set the initial timing to 10 degrees and hooked the vacuum advance up to the ported vacuum on my Holley. There is no vacuum at idle so fine it stays at 10 degrees. You give It a bit of gas it goes to 45 - 50 drgrees, still this is fine but at wide open throttle there is no vacuum either so now all you have is the mechanical advance of 15 degrees added to 10 degrees and you only get 25 degrees total. This is not enough, I thought you needed 36 degrees at WOT.
If anybody can give me a straight answer on this I will be forever thankful.
My car has run like a clock for five years with this setup and I see no reason to hook up the vacuum advance.
That being said I cannot figure out how it is supposed to be set up with the vacuum advance. This has been driving me crazy for some time now. This is what I tried, I set the initial timing to 10 degrees and hooked the vacuum advance up to the ported vacuum on my Holley. There is no vacuum at idle so fine it stays at 10 degrees. You give It a bit of gas it goes to 45 - 50 drgrees, still this is fine but at wide open throttle there is no vacuum either so now all you have is the mechanical advance of 15 degrees added to 10 degrees and you only get 25 degrees total. This is not enough, I thought you needed 36 degrees at WOT.
If anybody can give me a straight answer on this I will be forever thankful.
Thread Starter
Safety Car
Joined: Aug 2001
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From: Waterford Mi
Re: Distributer adjusting (MotorHead)
This is how I believe it is suppose to work.
If you disconect your vacuum advance and set you timing at 36 degrees @ 3000rpm you will see that your intial timing to be around 22 degrees @ 700rpm. The vacuum advance is used to add advance (15 degrees)during accelleration but drops it off at cruising speed for better gas mileage.
Thanks for everyones input.
Brian
If you disconect your vacuum advance and set you timing at 36 degrees @ 3000rpm you will see that your intial timing to be around 22 degrees @ 700rpm. The vacuum advance is used to add advance (15 degrees)during accelleration but drops it off at cruising speed for better gas mileage.
Thanks for everyones input.
Brian