Rear Spark Plugs on 3.4L

[cracker141]

I was wondering if anyone that has owned a '92 Lumina Z-34 longer than I have can give me some tips. Today I tried to change the spark plugs on my car. Had no problems on the front 3, but the rear 3??? How the heck do you get to them? I bought a service manual for the W body cars and it said to rock the motor forward in order to reach the back plugs easier. I took the one front strut brace off of the car like it said, put the car in neutral, and tried to pry the engine forward. It did not move. The manual made this sound like an easy thing to do. What am I doing wrong? If you have other tips to make this job easier please let me know.

-Thanks, AB

[ryan.hess]

Don't bother rocking the engine, PITA. what I did was notched out 3 slots under the weather stripping (you can't see it when it's on). Makes changing the rears a 5 min job. Don't cut more than 1/2" into the metal, any more isn't necessary. Just line 'em up with the spark plugs. So, cut maybe 1" wide x 1/2" deep, and you're good to go.

[blk92z34getrag]

Rocking the engine isn't that hard. Park on a hill with the front facing downhill, set the brake, and put it in neutral. Unbolt the mount, and it'll rock by itself.

I posted this already, but what I did was unbolted it, and stood (kneeled, whatever) on the front cam cover. That rocked it enough to get the plugs out.

Or you can back the car up onto ramps (i.e. Rhino Ramps), unbolt the mount... It isn't that hard, and the engine only moves a couple of degrees, just enough to get back there with a u-joint and long ass extension.

[cracker141]

Spark Plugs

Thanks Ryan for the tip about notching out the metal under the weather striping. I took a Saws-all and cut 3 flaps, one behind each plug. Then I bent them up and the extender things came up through the flap easily. When I got done I just bent the flaps back down and put the weather striping back. Your idea worked well, thanks for the tip, saved me time and money.

[SappySE107]

The "rock the engine" idea is only relevant on pushrods IMO. They have hydraulic lower mounts that suck balls, but allow the engine to rock easily. The DOHC has solid rubber and you aren't gonna have much give. If you do, your lower mounts are shot to hell.

[ryan.hess]

Re: Spark Plugs

Thanks Ryan for the tip about notching out the metal under the weather striping. I took a Saws-all and cut 3 flaps, one behind each plug. Then I bent them up and the extender things came up through the flap easily. When I got done I just bent the flaps back down and put the weather striping back. Your idea worked well, thanks for the tip, saved me time and money.

Good deal. Now you'll be changing the plugs in 5 minutes flat.

[Juglenaut]

Hah haa

Just watch the lower gaskets go bad and he could have replaced the plugs while replacing the lower gaskets.

[blk92z34getrag]

The "rock the engine" idea is only relevant on pushrods IMO. They have hydraulic lower mounts that suck balls, but allow the engine to rock easily. The DOHC has solid rubber and you aren't gonna have much give. If you do, your lower mounts are shot to hell.

Now that I think about it that was before I replaced the lower engine mounts... Perhaps notching the weather stripping isn't a bad idea now...

[Anonymous]

I have a pic of my rear set with the metal strip cut and a socket/extension in the spark cylinder on my website, under the "My 1992 Z34" page. Check it out if you'd like.

[Juglenaut]

I just used a 3 inch extension>'Snap-On' angle>3 inch+12 inch to clear lip from resting on the socket hub, on both my Z34 Auto and my GTP manual. No engine propping.

[Lyle's GTP]

HaHaHa, I got a '94 GTP no grinding, cutting, propping, rocking or intake removal required. It's still tight (like your sisters) but it slides right in. Oh Yah!

Lyle

[Anonymous]

[RednBlack]

Hey Ryan! Will this trick work on a 94 Cutlass too? I'm tired of spending 3 hours to change plugs. Wait a minute! I just checked! It works! My vote for the best tip of the year! Why didn't GM think of this when they built the car? Oh,... they are the same ones that forgot that this year was Leap Year, and all the clocks in Grand Prixs have the wrong date.

[Juglenaut]

I don't need to do squat to anything metal or anything that involves moving the engine. If you like cutting steel go ahead.

[RednBlack]

Hey, it's a couple of snips with a pair of shears. Not like cutting a fender off. It works, that's all I got to say about that. (Wonder why I never saw it in the first place.) TY Ryan.