Starting issues

Post by **callyspoy** » Tue Jan 05, 2010 10:18 am

Hi folks,
some of you may remember my post a couple of months back, asking about what battery to get. Well i got a high power super battery, which was nice.
So my issues still havent gone.
When i start the car in the morning it tries to turn over but seems like the battery is flat. If i turn the ignition off and turn it over(pull start) it spins merrily on the starter motor. So the power is there.
So...why is the power seemingly sapped the second i turn on the ignition? I jumped it in the end today and it fired instantly. The starter i got reconditioned in may i think. Hunch says something electrical...any ideas?
Ps-fiat running gear for those who dont know.
Cheers guys and gals.

Post by **PSL184** » Tue Jan 05, 2010 10:26 am

I would check first for a good clean engine to body earth. Make sure you have a good thick braided earth strap type. You might find that the accelerator cable (choke cable?) or some other such connection is trying to give an earth path and its not coping too well....

Post by **bmcecosse** » Tue Jan 05, 2010 10:42 am

Ignition too far advanced - and kicking against the starter?

Post by **callyspoy** » Tue Jan 05, 2010 10:53 am

There is a meaty earth strap on it, ill double check that its tight, but pretty sure it is.
BMC, my dad did mention that it could be that, but ithought as it spins it over fine with the ignition off that it might not be that. Ill retard it and check when i leave work today...

Post by **bmcecosse** » Tue Jan 05, 2010 11:46 am

Well - that's the clue - spins over fine with ign off ! When it can't kick against the starter!!

Post by **callyspoy** » Tue Jan 05, 2010 12:02 pm

Look, im a novice with problem solving!! I still dont understand though, i mean, if its turning over then there is compression yes? Whether ignition is on or not. If so then surely the problem would occur with ign on and off?
In no way am i questioning it, as you know infinitely more than me, just interested to learn!

Post by **bmcecosse** » Tue Jan 05, 2010 5:35 pm

No - because the high pressure only happens when the spark ignites the mixture. If it does this slightly before the piston reaches the top - it will oppose the movement of the piston. Now in nice warm weather - the engine spins fast enough to throw the piston over the top - even though the spark has initiated the explosion. But in cold weather - the engine isn't turning fast enough - piston approaches the top - spark happens - and the pressure wave pushes against the moving piston.
It's just an idea! May not be that at all - may simply be half flat battery! In fact - I think that is really more likely........

Post by **callyspoy** » Wed Jan 06, 2010 5:55 pm

You were right kind sir. Played, very primitively, with the timing, started first time. Its
not running quite as well, but i need to take the plugs out and see how they are looking. It was running sweet as a peach before, but i
sure the ugs will be fowled up judging by the solution to my problem.
Cheers roy.

Post by **bmcecosse** » Wed Jan 06, 2010 7:56 pm

" You were right kind sir " I'm always right - well - nearly always !

Ducks down to avoid bricks..........

Glad it's sorted. What you really need to do now - is to modify the dizzy internally - so it pulls up the advance after the engine starts. This should be done by the vacuum advance - as soon as the engine starts sucking air - it should pull the advance up. Best check it's working!

Post by **callyspoy** » Thu Jan 07, 2010 2:21 pm

Hmmm...pretty sure there is no vacuum advance on the dizzy...any other suggestions?

Post by **PSL184** » Thu Jan 07, 2010 2:45 pm

Mech advance with bob weights under the baseplate? Works by centrifugal force swinging the weights out which advances the timing the same way as a vac advance deos by sucking.

Post by **callyspoy** » Thu Jan 07, 2010 2:50 pm

That's what it has yes. Didnt know that the name was. Thanks! I
ean, if i had called them the swingy bits, you'd have all mocked me! Ha!
So i need to see if they are doing their thing which i assume is harder than a vacuum set up?!

Post by **PSL184** » Thu Jan 07, 2010 3:56 pm

Easiest way to check if it is working is to strobe your timing marks and rev the engine - If they timing moves then all is well. Manually, you should be able to twist the baseplate and it should snap back into place under spring tension....
Anyway, swingy bits sounds like a good description to me

Post by **bmcecosse** » Thu Jan 07, 2010 7:17 pm

Surprised there is no vac advance - no finesse these Italians.....
But yes - you should check the 'swingy' bits and make sure they are free.

Post by **callyspoy** » Thu Jan 07, 2010 7:28 pm

all this talk of swingy bits, i may just blush! stupid cap is screw on too! damn Italians!

Post by **bmcecosse** » Thu Jan 07, 2010 7:30 pm

How about a picture of the dizzy ?

Post by **callyspoy** » Thu Jan 07, 2010 7:47 pm

in this weather? you sound insane Roy!

Post by **MartinB** » Thu Jan 07, 2010 8:23 pm

bmcecosse wrote:Surprised there is no vac advance - no finesse these Italians.....

Proper engines don't need it!!

Post by **bmcecosse** » Thu Jan 07, 2010 10:31 pm

Hmmm - seems they do! But not if they are supercharged I grant you!

Post by **MartinB** » Fri Jan 08, 2010 9:48 am

I meant normal Fiat engines, not just mine!

When my 2 litre fiat engine was standard it didn't have vac advance and never failed to start. What Fiat ignition set up do you have, mine used to have the Bosch dizzy with the square black box (Magneti Marelli?) and was meant to be the least reliable type, although I never had any issues with it. Provided the timing is set correctly there should not be any starting issues.

Also before that when I modified the old 1098cc A series, when I had it rolling roaded I was told to remove the vac advance, it was a long time ago!

Martin