Tips before changing the spark plugs...

[JeanGoulet]

Many thanks to BrilliantBlackHemi and his photo-article on changing spark plugs. When the dealer asked me $230 dollars to do it once, I decided to evaluate my cost to purchase new tools and replacement parts over 4 spark plug service intervals. That's $220 for the next 200,000 km for me. Versus them at $920. $700 anticipated savings.

I completed the 16 plug job last night with success, including setting each one to the right torque.

However there are some important prerequisites I needed to assess before deciding to go ahead with that job, but they aren't mentionned in that article, so I thought I would write this.

It's because taking out spark plugs is the same as open-heart surgery, in the sense that you are exposing the innards that are not designed to be exposed to the elements.

And you have to be confident that you can sew up the patient completely, otherwise you may kill it. That means preventing disasters like cross-threading, introducing contaminated particles that may have wound up on your plugs, cracking the old plug, etc.). So even if you are under warranty, you are assuming these risks.

Before starting, as stated in the service manual, you need to prevent ANY particles from entering into the engine!

Here are the precautions I took, being outdoors initially:
- blast the engine with a vaccuum cleaner hooked up backwards and let the dust settle.
- keep the combustion chamber exposed to a minimum by preparing the new spark plug before taking an old one out.
- wait for a calm day (because there's no way I'm letting a windy day push around dust/dirt/leaves/bugs that could wind up in the compression chamber)
- keep the tools clean (imagine rust particles from old tools winding up you know where)
- work on a thermally static (cold) engine

One other helpful hint regarding the removal of the spark plug boot/coil pack is this: when they say "Remove coil pack by pulling upwards", they really mean "away from the engine along the axis that is perpendicular to the engine", or if you prefer "about 45 degrees relative to the ground". Not 90 degrees to the ground, which is what "upward" usually means...

[quarky42]

Good point. I'm going to go change mine right now ;?) (been meaning to for a few weeks now.)

[da BoMM]

Good point. I'm going to go change mine right now ;?) (been meaning to for a few weeks now.)

I want someone to change them for me -- but, $200 is a lot of coin for a 2 hour job. (It is a two hour job, right?)

[MikeEast]

I want someone to change them for me -- but, $200 is a lot of coin for a 2 hour job. (It is a two hour job, right?)

I'll change 'em for a hundred, hows that sound?

Mike

[da BoMM]

I'll change 'em for a hundred, hows that sound?

Mike

You got a deal! When can you do 'em? lol

[sizzortomgue]

I too don't want to pay $200.00 bucks for what is a a relatively easy job. My mechanic says the cost is due to the Upper Intake Manifold Cover. Is that the 'boot'?

I'm driving the Magnum for its aesthetics, not performance, so I have the 2.7 SE

Thanks anyone!

[NAS T MAG]

I too don't want to pay $200.00 bucks for what is a a relatively easy job. My mechanic says the cost is due to the Upper Intake Manifold Cover. Is that the 'boot'?

I'm driving the Magnum for its aesthetics, not performance, so I have the 2.7 SE

Thanks anyone!

The Hemi's have 16 plugs (2 per cylinder). I'm at 60,000 miles and having the dealer do them tomorrow!

[fnkychkn]

I too don't want to pay $200.00 bucks for what is a a relatively easy job. My mechanic says the cost is due to the Upper Intake Manifold Cover. Is that the 'boot'?

I'm driving the Magnum for its aesthetics, not performance, so I have the 2.7 SE

Thanks anyone!

the upper intake manifold has to be removed to access the spark plugs on 2.7L and 3.5L. it is not nearly as easy as 5.7L or 6.1L.

[gn300]

Is the 3.5 different than an LH car?

I don't have to take the upper plenum off my LHS to change plugs!

A vacume hose helps with the plugs as well ,but thats redneck enginering!

How? put the plug in the hose lower it down the tube and thread it in by hand less chance of cross threading when you can feel it by hand,then pull the hose off and use the wrench!

I'd bet it's more than 2 hours if you replace the plug wires too!

[fnkychkn]

Is the 3.5 different than an LH car?

I don't have to take the upper plenum off my LHS to change plugs!

A vacume hose helps with the plugs as well ,but thats redneck enginering!

How? put the plug in the hose lower it down the tube and thread it in by hand less chance of cross threading when you can feel it by hand,then pull the hose off and use the wrench!

I'd bet it's more than 2 hours if you replace the plug wires too!

intake manifold is completely different than LH.

[gn300]

Can't be a better design if you have to break the seal to change the plugs!

[Bsskng001]

plug wires...there are no plug wires on the 5.7s...just coil packs directly connected by boots to the plugs. Changing plugs is one of the easiest jobs...yes sometime manifolds can be in the way...but if you have the right tools, the job is much simpler,i did all my plugs (16 of them)..and gapped them all in about 1 to 1.5 hrs. 1/2" socket drive,6" extension and 5/8" deep plug socket,and a universal joint, i believe a 10mm socket for the coil packs,and a gapping tool. i used the 6" extention with the 5/8" socket(which has a rubber boot inside to hold the plug) and started threding it by hand then used the wrench to finish.

[JTSBLACKEXPRESS]

Just changed plugs on my 300/3.5.l The top section (plenum) was difficult to maneuver to get access to the back plugs, but I disengaged a metal pipe off the plenum. When I put the whole rig back together, it ran extremely rough. Turns out the pipe came loose and this was resolved when I maneuvered the pipe back into the plenum. Does anyone know what this pipe does and any suggestions on how to seal it. It appears to be fine, but I'm showing an "check engine" light.

[fogey]

I have plenty of plug wires on my 5.7 . They run across my intake manifold. Sept. 04 build date.

[srg]

Just changed plugs on my 300/3.5.l The top section (plenum) was difficult to maneuver to get access to the back plugs, but I disengaged a metal pipe off the plenum. When I put the whole rig back together, it ran extremely rough. Turns out the pipe came loose and this was resolved when I maneuvered the pipe back into the plenum. Does anyone know what this pipe does and any suggestions on how to seal it. It appears to be fine, but I'm showing an "check engine" light.

I haven't done the plugs in my 3.5L yet, but from what I've read you're talking about the EGR pipe. From what I remember, you're supposed to change the O-rings that seal the EGR tube at the lower end, every time the upper intake manifold is taken off.

The "check engine" light was turned on by the vacuum leak created when you left the tube off. If you managed to seal it back up, you probably can clear the code by pulling the neg battery terminal off for 15? minutes, or it might shut itself off after a certain number of start/stops. (As long as the tube is really sealed.)


srg