2002 SL2 168K Not an owner, but fixing one and liking what I see.
 

Okay, so I've been turning my own wrenches for 20+ years and I'm working on a 2002 SL2 that's meant to go to my niece once she's old enough to drive next year. I've been a fan of the Sky since it came out. It looks better than the bucktoothed Pontiac Solstice. I still want a Sky Redline.

Anyway, I'm mostly an Electronics/Computers guy. I live in the very North of Utah, USA. I have a YouTube channel I haven't posted to in years, but where I have covered some of my car repair adventures. I'm starting that back up because there's finally no reason not to. I hope I can provide some in-depth Saturn knowledge while I explore the kind of stuff there's zero information about online.

I don't see a teardown of the S-series AC compressor, for example. The TXV (thermal expansion valve) also seems to be a mystery, in terms of available info. It's not like any design I've seen anywhere else. But I've only used search engines like Google and Bing on that front.

This Autistic Staring Contest I've been in for two weeks with this SL2 should be made worth it. I'll post a thread in the relevant section regarding that.

Stay Zesty, Twisted Transistors - --|>|-- Fryode

The main thing to do on any of the 1.9 DOHC cars is to keep an eye on the oil level. They're know oil burners. Other than that, they'll run for a couple of hundred thousand miles with regular maintenance. Enjoy the car and welcome to the forum.

Welcome!

Welcome,
This may be a help.
https://charm.li/Saturn/2002/SL2%20L...OHC%20VIN%207/

Thanks! I was surprised when I did a compression test and every cylinder was just fine, despite the car being parked for almost a decade. The original owner thought it threw a rod. Not at all. People tend to assume the worst with older cars, though.

For the record, this car has 168,000 miles on it. The spark plugs didn't match and were way out of .040 gap spec. The ignition system is lost-spark like the 3800 SII I'm used to, but the coils and spark gaps are smaller so I suspect misfire nightmares. The interior valve cover gasket had broken loose and bathed every spark plug in oil so I assumed that seeped up the boots and became carbonized. I borescoped the cylinders and the pistons had carbon build up, but the cylinder walls still have cross-hatching(!).

The cold-start tapping noise is probably the timing chain tensioner, but my stethoscope points to lifter/rocker/valve-lash noise on Cylinder 2 because it's loud. Nothing I've seen on YouTube sounds the same. I can probably sniff that out with microphone probes and my oscilloscope. This is actually a good excuse to upgrade from a 2 channel scope to 4 channel. That's a win. I'll still probably install a timing kit, regardless. While I'm in there, why not?

The only difference between Science and screwing around is writing it down. Adam Savage said that. I believe it because I live it.

I snapped this attached photo of the top end. Looks clean to me, but this is my first DOHC engine project. The roller-tipped rockers surprised me. That's race car stuff. But so are cross-bolted main bearing caps, and those can be a corner-cutter. Shiny cams are a good sign, right?
https://cimg3.ibsrv.net/gimg/www.sat...9b3df7b77b.jpg
Valve cover had no sludge. No kitty glitter in the oil anywhere. Photo was taken before removing the gasket remnants on the right. The orange RTV had me concerned.

I apologize if the photo is too big. Same if this is the wrong thread to mention this kind of thing. I'd rather get my newbie mistakes out of the way ASAP and I appreciate any and all advice.

The tapping is most most likely the lifter.
The RTV is a cluster. There are preformed gaskets for these valve covers on the dohc. They fit down into the groove on the head and into the groove of the cam cover outer edge. Gaskets around each of the spark plug well openings are also included.
The only place you need to add a dab of RTV is where the front of the engine casting meets the rest. Just the smallest amount at those two points where the two sections come together and you'll be fine.
Sounds like previous owner did not attend to all of the vehicle's needs. Oil leaking from the cam cover gasket is oil that's no longer in the engine, so you don't know how low on oil it has been. If you are lucky, they did normal interval oil changes. I'm thinking it's a five-speed because you didn't mention it was an automatic.

What were the compression test results wet and dry?
With a vehicle at this mileage with an unknown maintenance history, doing a full timing kit on it makes good sense.

Be very careful not to distort the timing chain cover. Two bolts go through both the oil pan and the timing chain cover. If you forget to remove them first, you will bend the cover and it will not seal properly.

Use stock NGK plugs for the dohc in this engine.
It's a waste spark ignition. Just do it.

Getting the RTV removed was a pain. I already replaced the gaskets with a Fel-Pro kit. The plugs and wires are already done, too. I forget what plugs I used, but they weren't cheap. One plug tried to leave the crush washer behind. Saw that when I went in with the camera.

It's an Automatic. The trans fluid looks good. Shifts are smooth.

I don't know the difference between wet and dry compression tests. I saw 175 to 185psi across all four cylinders, but I also didn't crank for the same number of cycles on each one, nor for as long as the tech manual says to do. I was mainly looking for obvious problems on that front. I once had an Isuzu Rodeo with the GM 3.1L V6 that had awful compression on two cylinders. It also had nearly 200,000 miles on it, though. That's a hell of a run for a 3.1.

The woman who owned this car changed the oil every 3000 miles religiously. Seems like overkill. It was parked with 2200 miles on the oil and close to full on the dipstick. Found a partial bottle in the trunk. Mobil 1 Synthetic. Same as what was noted on the windshield sticker. Oil color is good. I'll do a change after all this is done and autopsy the filter for peace of mind.

Good point about the timing chain cover bolts. I was reading through the tech manual and wondered how often that's been missed over the years.

At the moment, I'm recovering refrigerant from the AC system so I can crack it open again and adjust the spring on the expansion valve to slow the flow. Suction pressure is supposed to be around 30psi, but it's around 95. The air's blowing kind of cold, but that high of pressure is wrong, especially when the high side is only 160psi. Way too low for summer in Utah.