Sparkplug replacement

Oh, man, I wouldn’t want to break a bolt on that configuration! The dictionary doesn’t have the creative words I’d growl!

Seriously, if I went through all that work I’d want to replace the gaskets. Seems to me like a much better approach. Valvecover gaskets are inexpensive. Might’s well do the job right.

For the record, if the seals at the bases of the sparkplug tubes are separate from the valvecover gasket, I’d change those too while I was there. In my car the tube seals are part of the valvecover gasket, but not all engines are like that.

This is standard procedure on many vehicles out there . . . has been for some time

Nothing Jeep-specific

Most manufactures began making engines in the 1990’s with inaccessible spark plugs, I think Jeep may have been the last with the current corporate 3.6L.

Yeah, I’m aware of that I was just surprised to see a manufacturer put it under the intake manifold for the first time. It’s bad enough my starter is under there.

One of the things I look for in buying a new vehicle is the accessibility of items for maintaining things and it’s just getting worse every year.

You should try to remove the rear spar plugs on a Silouette. First remove the engine mounts on the radiator bracket. Then rotate the engine forward. Next remove the coil pack. Then take the spark plugs out. You could also go in from behind, but without a lift, it is very difficult to get in position. Even with the lift, it is difficult.

It’s the V-Engines in a transverse orientation that creates the spark plug access problems, right? Transverse I4’s are usually no problem to get to the spark plugs, and long-ways V’s not much spark plug access problems with those either. What about transverse flat engines? Do they have the spark plug access problem too? Aren’t some Subaru engines like that?

There are no transverse flat engines.

Not necessarily. There are also V configuration engines mounted longitudinally known to require extraordinary measures to get at the rear plugs. GM used to be known for this on some of their vehicles, as they used to build the entire front subframe complete with motor and then drop the unibody over it, with seeming disregard for maintenance access.

But yeah, it’s usually the transverse V-style engines that have this problem with their rear bank.
Truth is, in many cases the I-4 engines in the same vehicle would sometimes outperform their V6 brethren. I read numerous times in magazine tests of Camrys of some years ago that the I-4 was the better performing version.

small cars with big engines have the same problem. The early Tbirds with big V8s required the engine be lowered to get to the rear plugs.

Today’s engines use long intake runners to boost low end torque. With the narrow angle V-6 engine (60 degrees), there isn’t much room for long runners, so they make them longer by running them out over the valve covers. Now add 4 valves per cylinder which puts the spark plugs in the center of the valve cover, that means the intake manifold goes over the top of the spark plugs, making them inaccessible.

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