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Hey all.

A spark plug question.

I bought my legacy with about 125K on it,

now it's got almost 200K, and I've never changed

the plugs, nor do I know when they might've been done previously.

So my fear is that when they are changed they might be sealed in there?

Can I spray anything into the plug area to make them come out more easily?

Wondering...

'97

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I don't have the answer to that question, others may know whether WD40 or PB Blaster would work.

 

I have fears of something dropping into the spark plug holes and doing engine damage, possible if you are not attentive.

 

Advice here is to just use OE NGKs not Bosch or any of those platinum, iridium, quattros etc....

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I watched a mechanic once take out old difficult plugs on a v8. I was a rather slow process where he alternately turned the plug out slowly a turn or so they sprayed lubricant into the plug hole. Then hed tighten the plug back into the hole a little, repeating this process until the old spark plug came out with the threads undamaged. The lubricant that you choose will not damage anything and will be beneficial for installing the new plugs. Torque them to approx. 15lbs. This is one reason I am not a fan of 100k plugs. They can seize in there and ive had several spark plug grommets dry out and leak and if you wait the interval it takes to drive 100k vs 30k you will be checking this part of your engine more often.

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A few pointers on teh job in general.

 

I use a somewhat rare 1" extension it seems on Subaru's.

 

On the drivers side I use a WAY long 3/8 extension to get the ratchet out of the engine bay.

 

ANti-seize the new plugs (I do di-electric grease too on the plugs/wires.

 

Don't be shocked if you find out and need to replace valve covers.

 

Some folks like ot do plugs on a warm engine, I prefer cold.

 

Old unknown plugs in an aluminum head is always a bit nerve racking.

 

Good luck

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I watched a mechanic once take out old difficult plugs on a v8. It was a rather slow process where he alternately turned the plug out slowly a turn or so, then sprayed lubricant into the plug hole. Then he'd tighten the plug back into the hole a little, repeating this process until the old spark plug came out with the threads undamaged. The lubricant that you choose will not damage anything and will be beneficial for installing the new plugs. Torque them to approx. 15lbs.

 

+2 on this method. I prefer PB Blaster myself...

Have removed many a stuck rusty bolt/nut with the same method (inclucing the little 10mm nuts that hold the fuel pump in place on a Legacy...). Time consuming, but if it works without breaking things, you take the time.

 

 

Yeah I already got the plugs from another older list on that topic.

I just wondered if anyone had ever sprayed into the plug areas...

I'm not even going to pull off the wires if I do it, I'm afraid they'll

break too if I try to remove them.

 

If you are so afraid of the wires, then perhaps they should also be changed? Old, brittle wires are not a good thing.

OEM or quality NGK wires - pull one at a time, match length and install - no problems, good to go.

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No harm in PB Blaster.  I buy it by the gallon and put it into a squirt bottle.

 

The back n forth things I always do on any stubborn bolt - with lube if possible.

 

Likely since this car is neglected you'll find oil in the holes due to VC leakage.  You may end up wanting or needing plug wires too.  If so I recommend OEM plug wires on the 2.5 engine.  SOme here say I believe NGK wores will work.  OEM's have never let me down and I believe close to the same price.

 

But you will need a nice collection of socket extensions.  I usually use a spark plug socket with a swivel built into it - S-K or K-D (I always forget).

 

Liek I said I always do thios on a cold engine with aluminum heads - I'm waiting for someone to say to do it on a warm engine - I believe some folks think this helps.

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Yes, make sure its cold first.

I've pulled plugs on plenty of warm engines and my 2.2 is the only one I've ever been afraid was going to pull the threads out with the plug, even with antiseize on them. I certainly won't be doing it again.

 

I agree with Heartless, if the plug wires are so brittle you're afraid to touch them, they should be replaced with the plugs.

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