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-   -   is it time to replace (https://www.rx7club.com/1st-generation-specific-1979-1985-18/time-replace-616591/)

notveryhappyjack Jan 22, 2007 06:23 PM

is it time to replace
 
just need a second opinion on this spark plugs. they look burned up and my car has been running like ass lately so this was the first place I looked.
http://i55.photobucket.com/albums/g1...g?t=1169511786 http://i55.photobucket.com/albums/g1...g?t=1169511787

notveryhappyjack Jan 22, 2007 06:24 PM

sorry for the blurry pics, I think I was holding the spark plug too close to the camera.

1badFB Jan 22, 2007 06:31 PM

The only thing to watch for is either the porcelain isolator cracking, or the electrode/grounds looking really worn out, pitted, or having a much larger gap than they originally did.
You should really clean all the carbon off them before you judge them, and its really hard to say from those pictures.

My opinion is if you doubt them, replace them. They arent expensive, and old ones can cause big problems if used too long. For what they cost, they are worth it to just replace if there is any doubt!

1badFB Jan 22, 2007 06:33 PM

If you do want an opinion though, take a picture looking directly at the center electrode on a non-reflective surface. You can see that you arent in too close, its just that your camera isnt focusing on the plug, rather the shiny red paint. :)

trochoid Jan 22, 2007 07:59 PM

The center electrode is what wears the most. When they wear, the tip shortens and rounds out. If the end of the tip is still flat, a good cleaning, I beadblast mine, should bring them back.

Rx-7Doctor Jan 22, 2007 08:35 PM

What exactly is running like ass?:)

Is it cutting out under hard throttle or falling off on the power band under load?
Does it feel like it is bucking or surging when cruising at a constant speed?
Does it just feel like it has lost some umph?
And by the way, keep that damn plug off of that pristine looking hood.:rlaugh:

1badFB Jan 22, 2007 09:48 PM


Originally Posted by rx7doctor
And by the way, keep that damn plug off of that pristine looking hood.:rlaugh:

Its on the roof! :)

notveryhappyjack Jan 22, 2007 11:26 PM

doc, what I ment was the car has a really low bouncy idle, about half the time when I push the clutch in the car dies for the first ten mins I drive everyday, hard starting.

I think my problem lies from when I put the car away in the middle of november I put about 3/4 a container of 'sta-bil' in the fuel system and its not running like it did before, for the first couple days after I started driveing the car again after a 2 months of sitting it was haveing a pretty bad hesitation problem, it was inconsistent tho. The car seems to drive better now after 150 miles have been put on it and I just changed the spark plugs earlier today, I'm going to run the gas tank down and fill up again and see if that helps.

notveryhappyjack Jan 22, 2007 11:30 PM

what are the signs that I need to refresh the carburator ? vacumme leaks ect and how to diagnose what needs replaced >?

I have been tossing the idea around of purchasing a carb repair kit from black dragon, is this a good place to start >?

notveryhappyjack Jan 22, 2007 11:35 PM


Originally Posted by rx7doctor
What exactly is running like ass?:)

Is it cutting out under hard throttle or falling off on the power band under load?
Does it feel like it is bucking or surging when cruising at a constant speed?
Does it just feel like it has lost some umph?
And by the way, keep that damn plug off of that pristine looking hood.:rlaugh:

haha I have a glass sunroof on my hood lawl the plug was really hot thats why in the second pic I'm not holding it :)
the engine feels like it has lost some umph, I kmnow that I have an exhaust leek where the header meets the mid pipe and that might be affecting my performance.

Rx-7Doctor Jan 22, 2007 11:45 PM

Run the tank down, replace the fuel filter and put a can of seafoam in the gas tank. Only put about a 1/4 tank of fuel in when you put the seafoam in. Run until near empty then see how she runs.

For vacuum leaks just get a can of Carb spray and remove the air cleaner assembly and spray with short spurts and see if the idle picks up.

If after you run the seafoam thru you do not see an improvement then it might be time to renew the carb.

Kentetsu Jan 23, 2007 01:29 AM

Thanks Doc, I was just about to suggest that. The Seafoam will break down any buildup that might be jamming your apex seals and such. I found that it also makes your sparkplugs look shiney like new just by running it through the tank as suggested (strong mix).

Supporting Evidence: Running late for a Saturday morning autocross. Since the car had been running like crap all week, I'd picked up some plugs for it a couple of days before but hadn't installed them yet. I pulled the plugs from the car, and sure enough they're all carbon'd up and pretty well worn (definitely in need of replacement). So I grabbed the plugs I had bought earlier and find old used plugs in the new boxes. wtf? Anyway, had to go racing without new plugs.

Well, I always try to use seafoam before a race if it's been a few weeks (usually a day or two prior to make sure it's out of the tank by racetime) but I hadn't done it yet for the same reasons I hadn't changed the spark plugs yet (basically procrastination). So I figured that since the race is about thirty miles away, and I only had about enough gas to get to the race, I might as well go ahead and use it.

Car was running great within a few miles. When I got back into town, and returned the plugs I had bought (guy thought I was trying to scam him too) and picked up new ones, I got to work on it. Pulled the old plugs out and they looked like new. Still very worn down, but very nice and shiney. :)

By the way, I really like the stuff....lol

notveryhappyjack Jan 23, 2007 04:59 PM

cool doc, I have heard to spray 'somthing flamable' at the carb and listen for the idle to pick up and note where its leaking from but was kinda scared to spray flamable things at tghe engine for obvious reasons :rlaugh: also doc is this 'carb spray' you speak of the same as starting fluid I have sprayed into the intake before when she won't start ?
kentetsu I know you love the seafoam, I last used seafoam on my engine about 6 months ago and liked the results, maybe its timne to use again.

Rx-7Doctor Jan 23, 2007 06:14 PM

Starting fluid is more flammable then carb spray is. Carb spray is what you want to use. And no you will not blow up.

1badFB Jan 23, 2007 06:35 PM


Originally Posted by rx7doctor
Starting fluid is more flammable then carb spray is. Carb spray is what you want to use. And no you will not blow up.

Ether starting fluid is nasty stuff. I wouldnt be worrying about getting blown up even though ether is highly volatile, Id be more worried about passing out. I dont even like using that stuff to start cars in the winter anymore. Stick to carb cleaner or even use an unlit propane torch.

I think some people actually have lit their engines on fire after trying to find vacuum leaks. I prefer the propane torch simply because it doesnt leave anything behind to burn!

notveryhappyjack Jan 23, 2007 07:53 PM

just a lil update, drove the rest of the old tank of gas off and put the new plugs in. The car drives way better now, going to use seafoam in a few days and that shou,ld help too.

allright so the stuf f I'm, lookin gfor is carb cleaner ? whats the actual brand name of it ?

thanks, aaron

Rx-7Doctor Jan 23, 2007 09:08 PM

Brand does not matter. Any carb cleaner will work.

Kentetsu Jan 24, 2007 05:05 PM

If carb cleaner is flammable, then why does the engine try to stall out when you spray it into the carb? I've never had any luck using the stuff to ID vacuum leaks. I use a rubber hose the way you would a stethoscope...


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