2 Problems: Rough idle at cold start. Radiator fan not working when hot.

You've identified at least one fail, no doubt. I've got a used gasket that looks just like it ;)

What cylinder is that? Passenger side rear?

I think it is the passenger side rear. Is that one particularly prone to failing?

(I'm not at the unit now, so I rotated the photo to make it upright and I flipped the image horizontally so that the orientation of the channels that coolant flows through matched the ones of the engine).
 

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Yes, pass. side rear is a very common location. Same thing I found on my '90.

No coolant in the oil, but bubbles/gases in the expansion tank, and plugged cats.
 
The two rusty bolts that were snapped off in the passenger-side head have been removed. One of them had to be drilled out, so we will replace it with a stud (that is slightly larger than the old bolt) and secure it that way.

I've removed as much of the old headgasket material off of the engine block as I could with a razor blade, brake cleaner, and a cloth rag. I've included a close-up of what it looks like (I left a little PB blaster in the cylinders to prevent rust). I saw a video where someone used a bristle disc and a fine Scotchbrite pad to clean off the engine surface, I was wondering if this would be ok as long as I follow-up with a straight edge and feeler gauge to make sure I didn't remove too much material.

https://www.youtube.com/watch?v=Uy5p-cUge5s
(skip to about 6 minutes in)

I got FEL-PRO PermaTorqueMLS 9263 PT and 9262 PT Headgaskets. I know they have a specialized coating that is a little more accommodating than regular MLS gaskets, but I want to get the best flatness and finish I can (preferably without pulling the engine).
 

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Discussion here on using MLS without finishing the block surface: http://www.sccoa.com/forums/showthr...ets&highlight=mls+without+finishing+the+block

About using scotchpads...they contain microscopic aluminum shards and I don't recommend getting them near any engine parts, trans internals etc. You might not see them, but they can remain behind and act like little hacksaw blades. I would also avoid power discs, etc, too each to create small gouges/imperfections, etc. Block sanding w/fine grit is what the dealers used to do, I hear.

The photos don't show any drama I can see right off...looks good from here - use your finger tips to feel for anything still attached, and clean up with alcohol when done.

About replacing bolts w/studs, be sure they cooperate with items that might rely on them when reattached, such as the dipstick and heater hose retainers, also confirm the manifold can be reinstalled without needing to pull them back out.
 
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Good evening


With the heads off the car and on jack stands here are some suggestions to inspect and or replace I regretted not doing and or was instructed by a engine machine shop to be aware of.

Upper Control Arms.

TEVES reservoir hose to pump.

Battery ground cable to driver side engine mount for corrosion.

Clean and treat underneath battery tray areas for corrosion.

Starter relay for cracks.

Ignition switch.

Heat sink compound underneath the DIS.

Spark plugs and wires.

Exhaust manifolds for evidence of leaking at the flange.

If manual check condition of the clutch master cylinder reservoir fluid.

Engine and transmission mounts.

Power steering hoses, pump and rack.

Radiator, oil cooler and heater hoses.

Condenser cleaned and combed. Replace both sides of the foam weather seal facing the radiator.

Repair or replace air dam.

Clean the intercooler.

Radiator professionally cleaned and pressure tested.

Change the thermostat and water pump.

Chase the thread holes on the cylinder head. Pay special attention to the threads for the valve covers, intake and exhaust manifold. Chase the thread holds on the intake manifold thermostat housing.

Chase the engine block cylinder head bolts threaded holes.

Inspect lifters, rocker arms and push rods for excessive wear. Replace if necessary.

If needed change the tension pulleys from plastic to steel.

If needed change the Supercharger, Jackshaft and Accessory belts.

Check service of supercharger oil. Inspect supercharger snout for evidence of oil leakage.

Change fuel filter.

Change oxygen sensors.

Inspect PCV system hoses and valve.

If needed adjust oil pressure sender fitting (driver side of the engine block) to gain better access to sender when the power steering bracket is installed.
 
Sorry for the long wait.

The engine is back together and it has been started several times. We’ve test-driven the car around the parking lot a few times and keep checking the fluids (especially coolant). Just as a precaution, I’m not going to let the coolant get much hotter than 180 degrees Fahrenheit until we’re completely sure all air bubbles are gone. After every time I run the car, I slightly loosen the vent bolt until a little coolant starts to come out between the threads. When the car is completely cool, I check the radiator cap and vent plug; always adding a tiny bit more to keep it as full as possible. We think virtually all the air is out by now, but we don’t want to risk it.

I’ll send pics next time ;)
 
About removing the bleed bolt now...at this point, I'd leave it, and the cap, alone and instead concentrate on the level in the expansion tank.

Minor air after filling is passed out via the expansion tank. That where you top off/adjust coolant later. If you keep opening the system, you'll just end up chasing the level.

When the cooling system is kept closed, coolant temp dictates the level in the system, and the expansion tank, via expansion/contraction, setting up a pressure/vacuum cycle, and every time you crack that bolt, or check the level in the radiator by pulling the cap, that dynamic is disturbed and has to be re-established by at least one more drive cycle/cooldown.

By the way, the factory manual says to set coolant level in the expansion tank when the engine is hot/fully warmed, up to the --HOT-- line. When it cools down, say by the next morning, note the level in the expansion tank just for reference. In my experience, when the cooling system is working properly and completely cooled down, the lower level will vary based on ambient air temp, but won't fall all the way to --COLD--. Don't adjust that level unless it falls below --COLD--.

Be sure the tube from the filler neck to the expansion tank is clear. Don't pull it off the filler neck just for fun, either, you'll disturb the pressure/vacuum that exists between the coolant in the tank and the cap and require another run/cooldown cycle to re-establish. If that tube is blocked, the upper hose will get rock hard when the engine heats up and collapse on itself when the engine cools down. Keep an eye on the level in the tank, and on the upper hose, every time you open the hood. Pretend the cap has a 'do not open' sign on it unless there is drama under the hood that demands you do so ;)

Again, set the level in the expansion tank when hot, at --HOT--, only. Don't open the closed up cooling system just to top off. Once repairs are done and you're confident it's working properly, leave it all alone and just watch the expansion tank.
 
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Hello everyone,

Im reviving my old thread when I replaced the headgaskets on my 1991 SC 5-speed (with moonroof) last summer. That car has not yet driven on a road since then, but Ive started it many times and driven it up and down my little street and havent had an issue yet.

However, in my new-to-me 1993 SC 5-speed (no moonroof) I found coolant/water in my oil. So I drained all the oil out and released the petcock on the radiator, letting out whatever I could ASAP. I guess its time to get MLS headgaskets again and maybe other things. Motor mounts, power steering pump, starter (looks old and dinged up), etc. Im glad I checked my oil level before starting because it was like 3/4 of an inch above the hashmarks (higher than I ever filled it). So I decided to drain some into a bowl and it came out watery.

Im kind of bummed out because I was about to work on that July video I kept teasing.
 
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