Urgent Dizzy Help Damn Gremlins!!

[KE ping it real]

Hi Guys

 

So i have just put a 7k engine in my rolla, and it seems to be all good, however for some reason, the mechanical advance in the dizzy isnt working!!

 

The distributor is a 5k electronic type with an internal ignitor, and has just 2 wires coming out from it

 

The car will start and idle, and we have set the base timing at 15deg, but when you rev the engine up, the timing doesnt advance??

 

I still have the original points coil with ballast resistor on it which i am planning to change but i don't think that would affect the timing as the car is starting and idling

 

Should i remove the ballast resistor??

 

And the vaccum advance is working as well because we did the suction test on that and it does work

 

Any and all help is appreciated, I am hanging to tune and drive this but this is the onlything holding me back

 

PLEASE HELP!!!!

 

Thanks

Andrew

[Taz_Rx]

Carbed yeah?

Checked the dizzy isn't locked?

[KE ping it real]

Yeah 40mm dcom sidedraft weber, how do you check if it is locked? if so how do you rectify it or do you have to just advance your timing further??

[bAKER]

Do 5k efi dizzys have mechanical advance?

[KE ping it real]

Do 5k efi dizzys have mechanical advance?

 

Nah its not an efi dizzy

[KE ping it real]

Has anyone got any further thoughts on this????

[towe001]

Do 5k electronic dizzys have mechanical advance?

Yes

[styler]

Old efi dizzy's still have mech advance as well last I looked, it's just an electronic signal pickup

and possibly adjustable dwell as well. Check the shaft isn't locked or seized by rotating top

of shaft, it should twist a small amount and then lock up, let go and it should spring back

 

Ballast must be used with ballast type of coil (so don't remove)

No ballast must be used with non ballast coil (so remove previous ballast)

Don't mix these up!

 

Must set base timing without vac attached.

Edited May 8, 2012 by styler

[towe001]

That was the 4k-e motor that was efi.

5k was carby only

[kickn5k]

Old efi dizzy's still have mech advance last I looked, it's just an electronic signal pickup

and possibly adjustable dwell as well. Check the shaft isn't locked or seized by rotating top

of shaft, it should twist a small amount and then lock up, let go and it should spring back.

 

That's the easiest way to do it, without pulling it apart.

I'm leaning towards it being locked.

Stu.

[Taz_Rx]

if it doesn't move strip the top out and check the springs/weights.

[KE ping it real]

Ok so ive pulled the dizzy out and the pulled the top off it, the shaft isnt locked up and the springs and weights all look to be ok (moving freely)

 

The one thing i will say is that when we set the timing, we did the base with the vac advance tube on, is this the likely cause being that we are trying to set the base with the vac already in play??

 

my mate thought it might be something to do with the module playing up? I don't know if that would be a symptom or not?

 

Thanks for all the help so far

Edited May 8, 2012 by KE ping it real

[KE ping it real]

Also, i will leave the ballast resistor alone, thanks for the tip ;)

[Taz_Rx]

It's called "mechanical" advance as there's no electronics involved.

[altezzaclub]

What happens if you run it w/o the vac on at all and use a timing light to check deg against revs. Then just draw an advance curve on graph paper.

 

I had this happen when I used too light a spring to hold the weights in, and at the 1000rpm idle it and already advanced through 70% of what the weights were capable of adding. That was when I was re-curving the electronic dizzy to get it to advance faster on The Girls KE70, as the 5K electronic dizzy I fitted had massive springs and never advanced satisfactorily..

 

You should have say 8deg at idle and another 25deg added by about 2000rpm. When you're accelerating the vac is zero, so you run purely on the weights. When you lift off the vac adds the extra 10deg to burn the lean mixture.

 

If you set it to 8deg with manifold vac on, say it adds 10deg, then you really have -2deg without vac. That means you will peak out at 15deg instead of 25 with the weights, which will make it flat at revs over 2500. It must show some advance when you rev it if those weights move OK, I think you just have the 5K dizzy problem..

 

http://www.rollaclub.com/board/topic/42407-the-girls-ke70/page__st__45

Edited May 9, 2012 by altezzaclub