Vacuum Advance on Distributor Non existent

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unknownmale
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Vacuum Advance on Distributor Non existent

Post by unknownmale » Tue Feb 10, 2015 1:28 am

So, like the title says pretty much.

There seems to be no advance on the distributor. There's no change at all if I suck on the vacuum hose attached to the advance unit.

Do I have to replace the whole distributor, or can i just replace a part?

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Nate
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Re: Vacuum Advance on Distributor Non existent

Post by Nate » Tue Feb 10, 2015 7:46 am

I wouldn't have thought you'd be able to suck hard enough to move the timing much. If you've got access to a mitivac it would be a better test.

Also need to check that there is actually a vacuum on the pipe. Lack of advance could be due to a vac pipe that has collapsed inside.

Assuming there is a vacuum on the pipe and it really isn't advancing, you might find something inside has seized. Some decent penetrative oil (plusgas or similar) may help you free it off


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unknownmale
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Re: Vacuum Advance on Distributor Non existent

Post by unknownmale » Tue Feb 10, 2015 11:53 am

Nate wrote:I wouldn't have thought you'd be able to suck hard enough to move the timing much. If you've got access to a mitivac it would be a better test.

Also need to check that there is actually a vacuum on the pipe. Lack of advance could be due to a vac pipe that has collapsed inside.

Assuming there is a vacuum on the pipe and it really isn't advancing, you might find something inside has seized. Some decent penetrative oil (plusgas or similar) may help you free it off
Hey Nate,

Thanks for the reply. Pipe seems fine, has good vacuum. If I attach it up it nothing happens.

I'll spray some WD40 down it this morning and see if anything changes.


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Re: Vacuum Advance on Distributor Non existent

Post by Nate » Tue Feb 10, 2015 5:15 pm

Please read my standard rant about wd40.

You might need to actually remove the dizzy or at least do some dismantling. Don't think just spraying oil down the vacuum connection will do much


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Re: Vacuum Advance on Distributor Non existent

Post by unknownmale » Tue Feb 10, 2015 8:38 pm

Fumbled my way through a cam belt change Sunday night, which lead to the lack of advance discovery.

It's my daily driver so can only do minor things until the weekend. Will get a good look at it then!


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Re: Vacuum Advance on Distributor Non existent

Post by mark1gls » Tue Feb 10, 2015 10:08 pm

What condition are the little bits of braided rubber hose which connect to the vacuum advance and plastic pipe in?


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Re: Vacuum Advance on Distributor Non existent

Post by unknownmale » Wed Feb 11, 2015 12:43 am

I don't have a braided hose? You mean those little 2 inch long bits on the end of old vacuum lines?

I have a vacuum line running after the manifold but before the booster straight to the advance unit. There is a tonne of vacuum at the end of the line (Around 20hg at idle),

Engine note, RPM identical if I block the end of the line with my thumb or if I connect it to the vacuum unit.


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Re: Vacuum Advance on Distributor Non existent

Post by unknownmale » Wed Feb 11, 2015 12:50 am

Couple of pictures, The red line.
1.jpg
2.jpg
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Re: Vacuum Advance on Distributor Non existent

Post by PeteGLi » Wed Feb 11, 2015 5:09 pm

You should be able to unscrew the vacuum unit from the body of the distributor and slip it out. Easily replaceable.



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Re: Vacuum Advance on Distributor Non existent

Post by go-for-it1 » Thu Feb 12, 2015 12:31 am

Check it is hooked over a peg on the inside which rotates the dizzy plate.


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Re: Vacuum Advance on Distributor Non existent

Post by mark1gls » Thu Feb 12, 2015 1:39 pm

The red hose looks to fat as its not the original hose, I may be wrong as Ive not seen the inside. The original hose is the same size as the connection.
"I'm sure I can suck on the end of my pipe and get my dissy to move!" (:-D ) I'll try it later and see.

Hoses on my car. The other hoses are the same size as the advance hose.
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Re: Vacuum Advance on Distributor Non existent

Post by unknownmale » Thu Feb 12, 2015 8:44 pm

Hey,

Yeah I replaced the hose the other day to see if that was the issue, it's not the original.

I'm going to take it out over the weekend and have a play with it, see if I can figure out what's going on...Currently I have two options (Too advanced, idle too high, overrun when I shut it off) or the opposite, low idle, but starts fine with no overrun.

To be honest, the amount of issues i've had with this engine the past year i'm more and more tempted to switch it out for an upgrade.


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Re: Vacuum Advance on Distributor Non existent

Post by Walshy » Sat Jan 25, 2020 1:50 pm

I have a question. My ignition advance has two vacuum pipes coming out. One from the back which is plumbed in like the picture above and one on top which isn’t connected to anything. Can anyone advise



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james butler
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Re: Vacuum Advance on Distributor Non existent

Post by james butler » Sat Jan 25, 2020 5:26 pm

hi unknownmale,
i have a spare second hand vac advance unit if you need it?
i tested it and works.


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james butler
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Re: Vacuum Advance on Distributor Non existent

Post by james butler » Sat Jan 25, 2020 5:29 pm

oh my i just realised how old this post is,
not sure walshy but can you post up a picture so we can see what you got?


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