Pull spark plugs with hot motor?


#1

Are the plugs going to come out easier with a hot or cold motor


#2

if they’re in so tight that it’s a problem either way, you overtorqued them last time.


#3

Cold. If the head is aluminum the threads could be damaged when pulling when hot. Also it is easier on your fingers and arms to work on a cold engine, flesh burns are very painful.


#4

i have never looked at them since i bought the vehicle. Seeing as how im to lazy to get up im going to ask if anybody knows if 95 jeep has aluminum head?


#5

The aluminum thing is not all that relevant, only b/c if I had a choice I’d do them cold no matter what.

I’d say the aluminum question is relevant only if there is some reason that you must pull them while hot.


#6

If it is an aluminum head, the aluminum will expand more than the cast iron used in the plug body so the plug will come out easier if the engine is hot. However, due to burn danger, I would pull them cold, only do hot as a last resort. I wonder if the OvGlove would help prevent burns.


#7

Im a big boy i can handle a hot engine but i b doin em cold. Thanks


#8

Spark plug threads are steel. The female threads in an aluminum head are almost always–you guessed it–aluminum. Softer than steel. Hot aluminum threads can “smear” when the spark plug is unscrewed.


#9

Copy that


#10

if plug are tight spray a little (P.B BLASTER) in well let sit overnight.it help me out.


#11

Perhaps you could compromise and go with warm.


#12

I’d pull them cold. Just be careful and if one doesn’t want to come out, don’t force it. Instead, loosen it a little, tighten it a little, repeat until you can ease it out of the head, even it it takes a while. Don’t overtighten the new plugs, and use some anti-seize compound to make it easier the next time.


#13

Anti-seize on the plugs…I use anti-seize on everything including wheel lugs as it helps to tighten.

Engine heat wont void anti-seize properties? (wasnt sure how else to say that)


#14

spark plugs should not be removed with engine hot, especially on aluminum engines.
risk of damaging the threads on the cylinder head can occur.


#15

Your Jeep has cast iron head/s, whether it’s the 4.0 liter or the 5.2. I’m assuming you have the Grand Cherokee. As a side note them plugs are due for replacement every 30k.


#16

4.0