Tried to help my boss with his LT5 ZR-1, minor fail.

That number eight plug. I thought I had all the sockets and extensions I would need to help him get that thing out, but turns out I couldn't get it either. The plug holes on the block are not much bigger than the plugs themselves and the angle is just so that you must need some really small plug socket with a swivel on the end to get in there. We found a socket online that someone recommended on corvetteforum and ordered that up. What a pain.

Whenever I find I don't have all the right tools available for simple jobs I get annoyed.

I have not done it on that car, but I have used a crescent wrench on the squared off outer end of a spark plug socket in tight clearances like that. Gotta be careful not to twist on the plug itself and break the ceramic though.

I agree about the annoyed thing. and I go from mildly annoyed by not having the right tool to majorly annoyed when I break something because I don't have the right tool quickly and on a far-too-frequent basis.

Yeah, he has 7 of 8 plugs swapped and I was not about to go at his low mileage ZR-1 with any makeshift efforts so we left the old plug in there. It's fine for now until we get the right tool.

I used to have an L98 C4, which of course is different but the plugs are a pain to get to on those too. I found that if you think of it as a plastic-bodied car with a metal frame, you realize that you can take off a lot of the stuff that gets in your way, such as the inner fenders. This won't help if the obstruction is the firewall itself, but short of that pretty much everything else can be unscrewed.

In reply to SEADave:

That's pretty much true of everything, really. And why I get a kick out of people who whinge about Audis being soooo hard to work on because you have to "take the front end off". I say, in less than ten minutes i can slide the "lock carrier" forward six inches and the world opens up. How long will it take to get the inner fender/frame rail off of a transverse engined car for the same ease of access?

Looking at pictures I'd think one of these would do the trick.

Kenny_McCormic wrote: Looking at pictures I'd think one of these would do the trick.

Yep, or perhaps a bmw plug tool would work perfectly.

I don't think there is anything that is easily removable on the LT5 equipped C4 to get to the plugs. I looked what is blocking it and...

A. It doesn't look like it has ever been removed. B. It seems to be the temp controller on the heater/ac housing that is doing the blocking.

Kenny_McCormic wrote: Looking at pictures I'd think one of these would do the trick.

Wat is dat?

Nobody can seem to settle on a name, but Hazard Fraught calls them square drive socket caps. Probably make your own out of a grade 8 bolt and a few minutes with a cutoff wheel and bench grinder.

The old F-body guys would take a spark plug socket and cut a window out of one side, similar to an O2 sensor socket, so they could slip the socket over the plug where there wasn't enough clearance to slide it over and put a ratchet in place. Something like this

With regard to the cap thing, I see, you put that into the socket or extension on the socket then crank on it with a wrench?

In reply to 06HHR:

This is the engine in question, the LT5 quad cam motor, I think we're even looking at the offending cylinder bank in this shot.

Harvey wrote: With regard to the cap thing, I see, you put that into the socket or extension on the socket then crank on it with a wrench?

Precisely.

In reply to Kenny_McCormic: Ugh.. Completely different than the F-body problem for sure..

Kenny_McCormic wrote: In reply to 06HHR: This is the engine in question, the LT5 quad cam motor, I think we're even looking at the offending cylinder bank in this shot.

Lower left is where the offending plug is located. It is kind of under those hoses running there and opposite that plastic housing in the corner, which is what blocks you from getting the wrench in there. Not to mention the plug holes are tiny, barely larger than the plug itself it seems, so you have no wiggle room with the socket, you have to get it straight in there.

Also, I had a short plug socket and I could get it to go into the hole, but then I couldn't get an extension on it, because of the angle. Those cap things might work in this case with a short extension, but it is difficult to get any extension on the thing once it is in. I think the short plug socket with the flex joint on the end is maybe the best bet.

I used to do a lot of work on twin engined yachts. For obvious reasons, it's a lot easier to get at the inboard plugs, rather than the outboard ones. At least half the time that I did a plug change, I'd find different brands of plugs on the two sides of each engine, The outboard plugs were probably the originals in most cases.

On a boat with a tight engine bay and raw water cooling, a sixteen plug change could take three or four hours.

I guess I was trying to say that you don't even need a plug socket or whatever if your spark plug socket looks like this (mine does, and I have put a wrench right on the end of it, works if you are careful about your angles). Then you don't have to worry about needing room for anything to clip into the back of the socket.

How does that work if the plug socket has to go all the way into the hole to get to the plug?

In this thread, nobody realizes that this is a DOHC motor.

Swank Force One wrote: In this thread, nobody realizes that this is a DOHC motor.

I'm pretty sure that I knew ZR1's had Lotus-designed, Mercury Marine-built DOHC engines before you were in kindergarten. Literally.

SEADave wrote:

Swank Force One wrote: In this thread, nobody realizes that this is a DOHC motor.

I'm pretty sure that I knew ZR1's had Lotus-designed, Mercury Marine-built DOHC engines before you were in kindergarten. Literally.

Wasn't really speaking to you, specifically, just more-so that i really don't understand some of these suggestions.

And for that matter, the car wasn't out yet when i was in kindergarten, so there, poopy-face!

I'm just joking around, but the issue still stands how to get that #8 plug out with the A/C in the way. I think the picture was a big help in picturing what the issue is. What would happen if you took off the valve cover? Would that get you better access to the plugs?

I'm wondering if it would even be efficient to do valve cover gaskets on this thing with the motor IN the car.

I found an article about removing cylinder heads on these guys. When it comes to the passenger head it says:

"Next, remove the A/C box on the passenger side of the motor. That is the triangle box with the heat sink inside it. To do this you have to disconnect the fuel lines and the upper bracket. Then there are 4 small 8mm bolts holding the a/c box on. The lower one is a real tough one to find. Now there is a good shot at everything for the time being."

So you may be back to just removing what is in the way, kinda like that smart guy in post #4 said earlier.

Again, I thought about it smart guy, but like I said, not my car and it doesn't look like anyone removed it before.

Also it's a ZR-1, the ZR1 is the new one.