Replacing rear sparkplugs...

[Sturmvogel]

What a freaking debacle... So far I rotated the engine forward, and removed the ICM, to get better access to the rear 3 spark plugs? No matter what I try, I seem not to be able to remove the rubber wire boots from the spark plugs; not to mention being able to get a wrench back there...

Anyone have any tips, or tricks?

[rockwood84]

the only easy way i have found to get at the rear sparkplugs and plugwires is to run the van up on a set of ramps or strattle a ditch .let it cool off and slide underneath it . go up beside the exhaust pipe and you can get at the plugs and wires.also this is the easiest way to get to the o2 sensor.use a short ratchet which also makes it a whole lot easier.

[merc81]

I was not able to even fit my arm between the engine and firewall on my Olds when trying from underneath, it was impossible.
If you already took off the coil pack, I think that's the way to go in there. Not sure how serious you were when you rotated the engine forward either. Unscrew the two bolts from the engine mount -- the mount that's underneath the engine -- and put a couple ratchet straps on the engine hoist points, one one either side.
Run the straps down in front of the radiator but behind the plastic bumper parts and back behind the lower part of the engine & frame. You can attach to the frame down there somewhere and then ratchet the straps up until the engine is about to damage the radiator. That should give you the room you need to reach back down there to grab the back spark plugs.

If you want more room than that, you can drop the front two bolts out from the subframe, but that's quite a bit more effort than rolling the engine forward. Don't try that without proper preparation or you & the van could be hurt.

[bigcoconut]

After you rotate the motor and strap it down, I had to remove the wiper linkage bars, coil paks, a bunch of electrical connections, the brake booster vacuum hose and the cannister purge sensor/solenoid (the small black thingy with two vacuum lines attached on its right side. BEWARE, make sure you put those two vacuum lines back on correctly. After that I was able to reach around with my whole arm and get a hold of the boots and plugs much better.

Be sure to use anit-sieze on the plugs (aluminum heads) and dielectric grease on the plug wires (plug and coil connections). Makes playing with them a lot easier in the future.

[rockwood84]

its a whole lot easier to pull it up on a set of ramps and go up beside the exhaust pipe.

[merc81]

Originally Posted by rockwood84

its a whole lot easier to pull it up on a set of ramps and go up beside the exhaust pipe.

I wish that worked for me rockwood84. I can't fit my arm between the firewall and the exhaust going up that way. I tried on 3 vans with no joy there.

[rockwood84]

Originally Posted by merc81

I wish that worked for me rockwood84. I can't fit my arm between the firewall and the exhaust going up that way. I tried on 3 vans with no joy there.

you don't go between the exhaust pipe and firewall .you reach up right beside the exhaust pipe .just follow the exhaust pipe up but you need a short handled ratchet as it is tight with a long handled one.but easier than doing all the rolling the motor.i changed my back 3 wires and plugs in less than an hour.the one reason these vans are so hard to work on anything around the motor is that the dealer pulls the motor and trans.puts them on a stand and works on them with plenty of room. then puts them back in.

[merc81]

Yea, that's me now too. I'd drop that frame out in a heartbeat rather then try to squeeze up in there to reach those plugs. I just can't fit in that space.

[kornjulio]

Easiest way is to do it when you do the LIM.....unfortunately....but at least you can count having to replace the gaskets before the plugs wear out....

[Cressidaadr]

Originally Posted by kornjulio

Easiest way is to do it when you do the LIM.....

I was thinking along that line. GM engineered the intake manifold gaskets to fail around every 50,000 miles and they just figured that would be the time to do the rear plugs too. Wasn't that one of the orginal selling features of these vans?

[rockwood84]

the spark plugs and plug wires are supposed to be changed 100,000 miles according to owners manual. you would think g.m. would have put more thought into the intake gaskets or at least when the intake gaskets started failing.but i guess they got used to going cheap back in the '80s when they had the crankshafts of the 305 motor made in mexico.but it came back to haunt them.