waltermitty

I need to change the coolant and plugs. The boots are seized to the plugs and are in a heat shield tube. Will it require a "special" socket to R&R the plugs?

Where is the radiator cap??????

I called the dealer to get a service manual. The parts guy said GM doesn't sell a manual. He did say Helms sells one but they are worthless because in order to use it you have to be hooked up to the GM website. Is this total bs?????

jnicewan

Those OEM plug wires can be a PITA. Dont know if it all helps but try these out. Spray penetrate oil (wd40) down low at the base of the spark plug, some of the oil might creep up between the plug and wire/boot. Twist/turn the plug wire to verifiy its not totally stuck to the plug. Get pliers or long needle nose and grip the the metal heat shield and pul straight out, even try to twist and pull at the same time. Be easy and try not to crush the metal heat shield but it can be reshaped after removal. It might help to disconnect the other end of the plug wires at the coils too. No special socket is needed for the plugs but you may want misc sizes of extensions and a universal joint or universal joint/plug socket.

I have simply had to replace plug wires before because some would just come apart. There is not a distributor or cap for that matter. Its not a coil on plug motor but close. The 8 individual coils are mounted on the valve covers with 3-4" long plug wires for each cylinder.
The radiator cap is on the overflow coolant reservoir. It is a pressure cap though, just on the bottle instead of the radiator.

waltermitty

Thanks for the info. I pulled the plug wire off the coils first then turned the boot on the plug until I felt it break loose. It was at least a half turn and maybe a bit more until it broke free. The metal heat shield comes off with the boot. I actually had to grab the metal to get a few of the boots off until I discovered the "boot twist" technique.

The plugs were relatively easy to R&R. I put some high temp anti-seize on the thread and silicone grease up in the new spark plug boots. Tried Auto Zone for the new plug wires but they were too long. The GMC Dealer had AC Delco wires @$120.00 so I went with them. The price bites but at least they are he correct length.

On to the coolant change. Still not certain how to go about it though. There isn't a tank drain on the rad. It looks like if I pull the bottom hose the block may partially drain. I think there are a few block drains but they could be oil galley plugs as well I guess.

Still open to suggestions on procedures.

waltermitty

Has anyone tried the Helms manuals for GMC? Got an opinion on quality?