Checking my plugs cos it seems to drop slightly while driving

What is the gap for the plugs

The manual doesn't have a figure. It says they don't need adjusting between being changed. I'd try a search on twinturbo.net

From what I've read (see, just trying to keep Hairsy happy.. Lol ), stock gap is 0.044"

 

Stage 3, people seem to drop this to 0.038"

Yeah Aaron I looked and it said between .039 and .044. I put it at .04 and my car is going sooo much better. Dont ask why, but it has made a difference to the point that I can feel it.

The plugs have done 50,000 miles and are getting to the point that they need changing.

 

What does it mean if the plugs are slightly sooty, running rich or burning oil. I dont think its burning oil cos I never have to top up my oil between changes.

 

Stuart

Out of interest, what were the gaps beforehand? I didn't gap my plugs when I put them in (I know, I should have.. didn't have any feeler guages at the time), so they are as they came from Nissan..

 

Sooty means it's running a little rich - oil would be a 'wet' looking black deposit..

 

Slightly sooty isn't much of a problem, heavy flaky black deposits would be though..

 

In fact having just reread your post, at 50k on a set of plugs, I wouldn't call a little soot a problem at all..

 

[This message has been edited by aaronjb (edited 09-02-2002).]

Sooty could mean running rich (lots of short journeys, cold starts etc), or running cool, in which case the deposits won't burn off.

I dont know what the gap was before. It was over .044 anyway. Well 2 of them where. the other wheren't that bad but I just made them all the same.

Its wasnt oil on them, cos most of it just blew off.

But I couldnt believe the difference with just cleaning them.

Think I will change them soon.

How the hell do you get the back ones off.

I only did 4 cos I could be arsed getting the back 2, and it was so windy my bonnet flew over and I heared a huge crack. I thought the window had gone, but it was just the wiper blade. Thank God.

 

Stuart

Stuart, to get at the back two plugs you have to unbolt the balance tube (two 12mm nuts on the drivers side, two 12mm bolts & a 12mm nut on the passenger side, and you might need to remove the one 10mm bolt that holts the idle support tube onto the right side of the inlet to be able to get the balance tube free from under it) and rotate it backwards (it's hooked up to a load of vacuum hoses, all of them bar the one to the fuel dampener should reach as you rotate the tube back)..

 

PITA design

Stuart,

Go to (www,twinturbo.net)get on the "Tech page" not the technical,i changed mine using this page it was easy.

 

 

Good luck Ken

 

[This message has been edited by SHREK/ZX (edited 10-02-2002).]

Oh I forgot,

 

Here's probably the best tip I ever had for changing spark plugs, especially on OHC engines where you can't get your hand to the plug top;

 

Get a length, about 12" will do, of either 6mm silicone hose, or 8mm coolant/fuel hose.

Push the spark plug into the end of the hose, so that it's snugly on there

Dangle the plug down into the well with the hose, and sit it on the threaded hole

 

Now start the plug off by turning the hose, it's impossible to cross thread the plug this way.. If by some chance the plug does start off cross threaded - the hose just slips on the plug, unscrew it and try again..

 

Much much better than starting off with a socket & extension and risking cross threading the plug (very easy on soft aluminium head engines like ours).

 

I know you've done 4 already, but I thought I'd share that tip.. (I have a length of old 6mm silicone I use for just that.. works a treat)

Changed all six of my spark plugs today - what a pain in the ass job that is, but with 54,000 miles up the time was about right. I replaced them with HKS jobbies from Johhny boy (of course). When I took the old ones out I looked at the gap and thought "f*ck me, you could drive a bus through there !". When I measured the gap it was between 1.0mm and 0.95mm. Seemed kinda large until I translated 0.044 inches into new money. 1.1mm (approx) - Zeds must have bloody powerful ignition systems, I never remmember bike spark plugs having gaps like that, and they had individual coils per plug. Anyway, started it up and it seems fine, real test will be tomorrow morning.

 

Incidentally, the HKS plugs have significantly smaller gaps, forgot exactly how much now, but I think it would have been between 0.9mm and 0.95, as you're not supposed to mess with them though I left them as they were - time will tell whether that's right or not ...