Jfrahm

Er, also if you haven't already, make sure the cooling system has been properly bled as a big air bubble can cause weird problems. There are plenty of threads on how to do this properly so I won't get into that.

BoulderGeek

Thanks, all, for the constuctive help.

Joel, that Advance Auto is right in back of my house, so I am very familiar with it. I will try the pressure tester.

I checked it, yesterday. I had a spirited drive back from Boulder to Lafayette via Valmont, and hit 75 on 287 (whoops). As I pulled in to the driveway, temperature went from first 1/4 tick mark to 3/4. I pulled in, shut it down and popped the hood. Fans were on high, no steam, no drips, coolant at MAX line. Fans went off after a minute or two.

I am also trying to debug my power steering drip and occasional loss of power. i got the PS pump rebuild kit and new banjo bolt + crush washers. I guess I will get in there sometime and so the PS lines and pump. With that, I may try to swap coolant lines, as possible.

Also slated to install new distributor cap, rotor, plug wires and plugs. So, that should tell me something about the plug conditions.

Jfrahm

I was actually trying to suggest getting a tester from somewhere other than Advance as I know the one at advance is not easy to use on our cars. None of the caps fit so I had to use the expanding plug-thing which popped out a few times.

If your system has not been bled it's worth trying to bleed it first, a pressure tester makes this easier but is not necessary.

BoulderGeek

Gotcha. OK, thanks for that. I thought you said what they had would work, though not optimal. They are my closest shop, so small world.

I have read a bunch of articles today on the bleed process. I will do that this weekend. I bet I can feed 10PSI into the reservoir from my cheap compressor, which has a very controllable feed valve.

The car hasn't been using coolant this week, but temps do occasionally do go up to the 3/4 mark, then back down.

Doing the bleed and resealing the tail lights are on the task list for Saturday. I also have a big set of LEDs that I want to try in the gauge cluster and interior lights. Steering wheel is coming off. I have new driver's door trim to go on. Plugs, wires and distributor cap going on. Drain tubes to clear or replace. Rust to repair and front air dam paint to resurface. Oh, power steering pump remove and reseal! Then we will look at the hoses and fuel lines.

dmjames

Any luck in tracking down this issue with coolant loss? I'm seeing very similar issues with my 84- no signs of a head gasket leak yet, oil and coolant look clean (no contamination), no puddles...

Turns out that the coolant system pressure tester that O'Reilly carries as a rental tool works great and seals with no issues. System held about 8psi of pressure overnight, cap tests good, and the car is keeping itself in the normal range temp-wise... If I had't been looking at the coolant level anyhow, I'd never have suspected an issue!

Guess my next step is to check for a steamed spark plug. I saw a recommendation of doing the pressure test again with the plugs out, since that could let a head gasket leak show up as a bigger pressure drop- fingers crossed that it's something stupid somewhere else, as I've got plenty of deferred maintenance from the PO to work my way through otherwise.

dmjames

LMK if you like the ones you picked up, and where you found them- I've seen a lot of options, and most of the info isn't the most recent...

BoulderGeek

I bled the air from the top of the block, and topped up the coolant level. Surprisingly, I haven't had more coolant loss in two months.

I have no idea what the issue was. I got up to about 12 lbs of pressure with the pressure tester, and had no bubbles.

I am going to be replacing my heater control valve and lines, this weekend. So, that will introduce air into the system again. Hopefully I can bleed and fill and be back to a working system without super high heat all the time.

The LED lights worked OK in the gauge cluster. Just the little bayonet bulbs (can't recall the numbers) that fit into the holders. I cleaned the old silvering compound off of the reflector guides, usung nail polish remover and paper towels. Once i had clear plastic, I used a few drops of superglue to glue down heavy duty aluminum foil over the guides. Then I covered in duct tape to protect. I got the lights from SuperBrightLEDs.com. You can usually find a 10-15% off coupon somewhere.

I can see the gauges fine at night. The far right side Fuel Pressure and Gas gauges are darker, but the other main dials are fine. I consider putting in a small LED strip light at the bottom, whenever I need to take the cluster out again.

dmjames

Funny, turns out I had the exact same experience! I guess I wasn't anticipating that much of a drop after running a bit, but I'm happy to not be tracking down random coolant leaks or, worse, a dying headgasket!

BoulderGeek

It was fun to run into you, picking over all of those old parts.

My next project, speaking of coolant, is the heater control valve (still) and the upper radiator to block hose, which is really soft. Not excited about having to protect the belts and clutch, and to have to bleed the coolant system again. But, those lines have to go.