New Zealand Datsun Club

Bartman wrote:What does the engine do when it hits 4000? Does it just refuse to rev higher? Does it splutter and cut out? Or start to missfire?

It splutters and cuts out. I haven't got the timing perfect yet.
But it did do this with the old dizzy too. (Before it wore out)
Its done it the whole time ive had it.. Even when we got her going at my grandads.
I know that the vacuum advance is ok, the old one had slotted out and didn't work at all.
Im a little lost now... Do i replace the ballast resistor or not? its only .2 Ohms up from what i should be.

I'd be surprised if that was the problem, you could by pass it to test if that made a difference, put + cable of Ballast to + of Coil, then run engine, don't remove + cables from Coil or it won't start. If no change then Ballast isn't the fault. Can you drive the car?

classicdat wrote:I'd be surprised if that was the problem, you could by pass it to test if that made a difference, put + cable of Ballast to + of Coil, then run engine, don't remove + cables from Coil or it won't start. If no change then Ballast isn't the fault. Can you drive the car?

Yeah its drivable, it definitely wont rev pas 4k hot or cold under load.
But when its up to temp it will rev past 4k to about 5.5k while stationary.

Ill go try bypassing the ballast resistor now. I'm going to put new nolathane front sway-bar bushes in now to.

Ok, Ive tried putting the ballast + wire to the + on the coil with no change. but she is running worse than yesterday...
Now im really confused.
Could it be the coil on its way out? Its coughing and spluttering like nothing else

But on a positive note, Ive got the new bushes on the front sway-bar and i can tell just by looking at it that it has made a difference.
The old bushes were not to bad, but the passengers side was definitely worse than the drivers side.

If I was you i would check all HT leads, spark plugs and even see what the coil spark looks like. take the king lead off your dizzy and put a screw driver in the lead and hold it near a earth, should be a nice blue spark pretty easily seen.

You could also check the resistance of your coils primary and secondry windings

Another easy thing to do is take the aircleaner off, start the car, hold about 2500 rpm on it and put your hand over the top of the carb to prevent air getting in, as engine dies remove your hand, as revs climb repeat. The goal is to suck anything little that is partially blocking the jets through and clear them

mindgem wrote:If I was you i would check all HT leads, spark plugs and even see what the coil spark looks like. take the king lead off your dizzy and put a screw driver in the lead and hold it near a earth, should be a nice blue spark pretty easily seen.

You could also check the resistance of your coils primary and secondry windings

How would i test the resistance of the coils windings?
I'm fairly clued up on auto electrics, i just need to know where im testing and how many Ohms it should be.

And Ill give that a go cheers Vaughan.

Ill let you guys know how i get on....

Disconnect your coil and check the resistance between the + and - which is the primary windings if i remember correctly, and then from where the king lead goes to the - which should be the secondary.

my coil reads 1.2 Ohms primary and 16.82k Ohms secondary but that being said i am using a gt40r which could be slightly different from the original

Cheers Alex, Ill give that a crack on Sunday If the weather is good.