Do sparks plug need to be put in a certain way..?

[tee]

Yes I'm having a blonde moment, suns fried my brain. I put some new plugs in my 280zx and now it's not starting, engine turns and exhaust pops but no start up. Anyone shed some light pls

[Deleted]

did you do them one at a time and put the leads/coils back on as you went? if not maybe theres a wire crossed somewhere...

[Mystery Machine]

Errr...yes, you screw them in. Not sure how else you could fit them?

Your comment is a bit vague but my first port of call would be to check and double check that you've A) got the right plugs and B) got the plug leads on in the correct order.

[scoobypete]

Also might be worth checking the plug gap?

[akku]

so long as the electrode is in the pot and the terminal is facing out...



the leads may be in the wrong order?

also its worth reading up on "indexing spark plugs" one time when you want to see how picky some people are when setting up engines...

[will]

Never heard of indexing before. I had a think about it and was most pleased when wiki agreed with me Might have a go at 'tuning' my Honda cg125 commuter ;D hack tomorrow

wiki quote v v v

A matter of some debate is the "indexing" of plugs upon installation, usually only for high performance or racing applications; this involves installing them so that the open area of the spark gap, not shrouded by the ground electrode, faces the center of the combustion chamber, towards the intake valve, rather than the wall. Some engine tuners[who?] believe that this will maximize the exposure of the fuel-air mixture to the spark, also ensuring that every combustion chamber is an even in layout and therefore result in better ignition ; others, however, believe that this is useful only to keep the ground electrode out of the way of the piston in ultra-high-compression engines if clearance is insufficient. In any event, this is accomplished by marking the location of the gap on the outside of the plug, installing it, and noting the direction in which the mark faces; then the plug is removed and additional washers are added so as to change the orientation of the tightened plug. This must be done individually for each plug, as the orientation of the gap with respect to the threads of the shell is random. Some plugs are made with a non-random orientation of the gap and are usually marked as such by a suffix to the model number; typically these are specified by manufacturers of very small engines where the spark plug tip and electrodes form a significantly large part of the shape of the combustion chamber. The Honda Insight has indexed spark plugs from factory, with four different part numbers available corresponding to the different degrees of indexing to achieve most efficient combustion and maximum fuel efficiency.

[crazymonkey]

could be the leads wrong order more than likely. Made that mistake on our old favorit once. wouldnt start but did do an impressive discus throw when it popped the oil cap off the top of the engine and about 50feet into a neighbours garden. Twice

[tee]

sorry guys my original question wasn't even asked right, I was referring to the leads being in the right order, i think I've put them on wrong order and thats why its not starting. Can this do damage? And are there any indications to show what order they should be put on..?

[Mystery Machine]

Won't cause damage but you'll need to find a reference for the plug lead order (haynes manual, owners club forum etc...)

Just follow it carefully one lead at a time - remove them all from dizzy & plugs then work your wY around the dizzy one lead a a time.

[ben711200]

**Assuming you have an old tech engine with a dizzy rather than coilpacks and 4 cylinders

You'll need to get the engine to top dead centre (tdc). If you take the dizzy cap off, the rotor arm should be pointing roughly to where number 1 HT lead should be (number one being the end with belts, not the flywheel end).

That's your starting point. You need to find out the firing order (I think probably 1-4-3-2 or 1-2-4-3) and the way your distributer turns. My Fiesta, for example is 1-2-4-3 and anticlockwise so that's the order and direction you'd put the leads back on.

Hope that helps, that I'm not teaching you to suck eggs and that I haven't said something daft by accident

[alx]

Just did a quick google for firing order of a 280zx and it seems to be....

from here www.zdriver.com/forum/showthread.php?t=17728
Firing order is 1 5 3 6 2 4., rotation is counter clockwise. Came from A haynes manual for the 280zx 79-83.

And from here www.zdriver.com/forum/showthread.php?t=17728 there's a diagram (bearing in mind it's an American forum, so car will be left hand drive)





HTH

AL.

[DavidB]

LOL, always have difficulty with firing order and correct leads to dizzy.

[ejenner]

It is certainly one of those 'ohh-' moments when you've realised you've just messed up the order of the wires and you will have to work out how they should be connected.

The reported symptoms in the first question are classic signs that the leads have not been connected in the right order.

The solution has been posted above.

It can do damage. Trying to start a car when the ignition timing is wrong can lead to explosions in the exhaust pipe. If you're unlucky it can split open a silencer down the seam. Seen it happen. Blew open like a crisp packet. One half was touching the ground and the other half hit the bottom of the car. It was a brand new silencer as well!

[tee]

All sorted ta!

[datman]

BTW, for the help of anyone else reading.. on Datsuns, there is a rib moulded into the dizzy cap on the side , this shows where number 1 plug lead goes. So if you know that and the firing order, and the rotation direction (anticlockwise on those) sorted. The ORIGINAL HT leads had numbers printed on them for the cylinders, making getting them wrong pretty much impossible.