42 replies to this topic

[Massee]

Hi new to the forum, having problems starting a rebuilt engine, I've checked all the usual starting problems, I'm getting fuel through, there's a spark.im just having an issue with the voltage at the coil, it's 12 volt with ignition on then drops to 9 volt when turning, does this mean it's a ballast wiring set up? It's a 12 volt coil? Any advice appreciated

[sonscar]

That will not prevent it starting.Pretend I just brought you the car and check everything again.Correct stroke?correct firing order,correctly set tappets,compression?charged battery?choke ok etc etc.Not trying to teach you to suck eggs here but I find stepping back often helps,Steve..

[Massee]

The engine was rebuilt by good garage, I haven't checked tappets, is that worth checking?

[Quinlan minor]

The engine was rebuilt by good garage, I haven't checked tappets, is that worth checking?

As sonscar pointed out, above, until it starts everything is worth checking.

[johnR]

Try moving distributor round in increments?

[coopertaz]

ballat set up reduces voltage to coil when NOT cranking a drop to 9v under cranking is just battery voltage dropping. at 9volts is engine cranking over fast enough, check distributor by lining crank timing mark up with no1 on firing stroke and check rotor arm pointing to no lead may well be 180degrees out

[Massee]

I've had another go at it 2day, still not starting.theres a spark at all 4 plugs, fuel getting thru, checked no 1 at tdc and rotor arm was at 3 o'clock, I then move dizzy drive back to next position, then checked rotor arm, it was at 12 o'clock. I've had leads in different positions and moved dizzy, only thing next to check is valve clearances but would that make a difference?

[sonscar]

Stop randomly moving things.Read the book and set it properly.Verify with a timing light about 10degrees BTC should start it.Steve..

[Pete649]

Just to double check, firing order is 1, 3, 4, 2 and the rotor arm turns anti-clockwise.

[cal844]

9 volts is too much drop on the battery during cranking. Get hold of a fresh (not one that's sat about on a shelf for 6 months) 063 size battery and fully charge it. I bet it cranks up within seconds.

Are the spark plugs wet with fuel after cranking?
Are you using enough choke (or too much)? What is the battery voltage during cranking?

What is the voltage during cranking on the coil positive? (what wire colours are on the coil?)


You need to check timing is set on correct stroke and that the valve clearances are set correctly...

Most important of all, how old is the fuel you are using?

What I'd do now is to pour a small amount (25 to 50ml will be plenty) of fresh fuel into the carburettor throat and see if it fires, runs and dies... If it does run it's a fuel issue, if not keep looking as its likely electrical or timing.

Coil wiring for a 12 volt car is White for coil positive
White/ black strip for negative.

Coil wiring for a ballast car is

Pink/white for coil positive (this is the ballast resistor)
Yellow/white wire to starter motor bypass feed)

white/black on cool negative

Edited by cal844, 09 August 2023 - 09:20 PM.

[viz139]

If you cannot get the distributor drive in at the correct angle ( between 1 an 2 o clock ) at TDC  it is possible the cam is timed wrong. Do a compression test and if its low remove the timing cover to check the chain position.

[Massee]

If the cam timing is out, would it have been done wrong during rebuild or is it possible for chain to slip a tooth?

[Massee]

This is where it is no 1 at tdc

[Massee]

This is where it is no 1 at tdc

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[sonscar]

Fit the cap and put a mark on the dissy body level with no 1 post.Remove cap and the rotor should be level with this mark.Turn the dissy until it is.Steve..