Tune-up and general clean up of the engine

I decided it was time to do a tune-up of the engine after she has been driving the car for about a year now. I had wanted to change the plug wires out from early on. The engine ran great once I got it running so I wasn't in a huge hurry and I wanted to learn more about the LT1 before diving in.  
I knew the distributor had at least been off the engine once since the plug wires were marked with a paint pen. Also who ever was last in there nicely left off the spark plug wire holders! So the plug wires have been flopping around and rubbing on everything. I also noticed a bunch of RTV/silicone on the thermostat housing, but I got rid of all of that when I changed the thermostat, gasket and coolant.

The intake manifold has a bad oil leak, mostly in the rear but some in the front as well. I have a gasket set, not sure if I am going to do that now or wait a little while.

I have pulled most everything off the front of the engine, not a bad job just takes time. The water pump had a bunch of RTV/silicone gooped up around the gaskets and slightly in the ports, luckily only on the pump and not much on the block. The balancer came off fairly easily without the use of a puller. The distributor came off easy enough. The unit was coated in a nice layer of oil and gunk as was the timing cover. The timing cover and front of the engine cleaned up decently with brake cleaner and a rag. Didn't have to scrape too much around the water pump ports.

I had to buy some tools to work on the distributor.   I didn't have any E-torx sockets or a t-8 bit. I took the cap off and the inside was fairly clean, only a slight bit of oil in there. The cap and rotor show some wear but nothing too bad, certainly not 120K miles worth...

The o-rings on the water pump and drive as well as the distributor were hard as a rock and flattened out.

I pulled the two seals and installed the larger one without issue. The water pump drive one I managed to mangle and had to buy anther gasket set... Second time I got it on there pretty easily using the pump drive as the installation tool. I then reinstalled the distributor.

I still have to replace the spark plugs and wires, put the water pump back on and the rest of that stuff...

here are some pics, I was too dirty to get pics before cleaning
after cleanup
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distributor after removal
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new cap/rotor and cleaned up
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distributor reinstalled
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Did you verify that the distributor holds vacuum, and loctite the rotor screws?

sherlock9c1 wrote:

Did you verify that the distributor holds vacuum, and loctite the rotor screws?

I did not verify if it holds a vacuum, but I still can easy enough.
The new rotor screws came with blue locktite on them.

I disconnected the vacuum line at the filter/check valve thing by the valve cover and used my hand vacuum pump there. I put my finger over the blue elbow for the air filter pipe and was able to get good vacuum.

Had the wife help change the plugs and wires on the passenger side. She was under the car doing most of the work... Tomorrow we will tackle the drivers side.

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The old plugs were NGK TR55GP with a huge gap! about .060+ She did mention that the engine seemed to bog or break up under full throttle...

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I got AC Delco R44LTS plugs and AC Delco wires.

60 is the standard gap for these needle electrode plugs. Check your spec label on the radiator frame.

Do you have a photo of the INSIDE of your original distributor cap?

The spec on the label is .050"

I can take a couple pics of the old cap and rotor. It wasn't in too bad of condition, pretty sure it had been changed out at some point.

old cap:
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not brass terminals
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rotor
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not a huge amount of wear on them...

We replaced the drivers side plugs and wires this morning. Bit of an interesting job getting wire 7 into the holder behind the manifold down pipe... Otherwise I was able to reuse what was left of the clips to hold the wires from flopping around too much. Several of them are missing.

I also changed out the battery cables and installed the new starter and reinstalled the water pump. I did test start the engine before putting the water pump on. Still have to install the mechanical fan stuff and add coolant.

I got everything back together yesterday morning. Made a nice mess bleeding the cooling system... otherwise all seems to be good.

next project might be pulling the intake to reseal it.

That's a job I'm gonna have to do soon, thanks for all the photos!

That opti looked pretty good; honestly I'd probably just run it as-is. How many miles were on it?

On bleeding, make sure the bleed screw at the water pump is the ONLY thing open in the system, otherwise it will not force all the air out. Make sure the expansion tank cap is on and tight before opening the bleed screw.

sherlock9c1 wrote:

That opti looked pretty good; honestly I'd probably just run it as-is. How many miles were on it?

On bleeding, make sure the bleed screw at the water pump is the ONLY thing open in the system, otherwise it will not force all the air out.  Make sure the expansion tank cap is on and tight before opening the bleed screw.

I am not really sure on the mileage that was on the opti, plugs and wires. Unfortunately we did not get any maintenance records when she bought the car. I know the car had a bunch of work done on it not long before it was parked, which was about 14 years before we got it last year. This is based on the condition of the brake pads/rotors and shoes/drums. They showed very little wear, aside from the brake rotors being shot from rust do to sitting.
As a guess I would say it was brought in for a 100K mile service. The car had a 112K on it when we got it.

Thanks for the tip on bleeding the system. I do think I managed to get all the air out.

Never hurts to do maintenance, even more so on a 90s GM car that sat for a decade.

Never had an issue with coolant bleeding. I put a rag under the hose and crack the bleeder until I get a couple of drips. Drive car around again, repeat. Do that a couple of times and all the air is gone.