74 NovaMan’s … Novas

[74NovaMan]

The swings, especially on the way down (from 220 - 180), took only seconds. Seems to scream air bubble doesn't it?

Ever drilled a hole in the thermostat to eliminate trapped air?

[TheSilverBuick]

I do typically drill ~1/8th inch hole in the thermostat, however I find the results mediocre. I think because it bleeds air too slowly, hence why I switched to pulling the heater hose. I still do the ~1/8th inch hole anyways out of habit and I don't believe it hurts anything.

[Scott Liggett]

Sounds a lot like an air bubble in the block. I drill two or three 1/8 or 3/16 holes in the thermostat. It allows air to escape pretty quickly.

Also, if you are still using the old radiator cap, get a new one.

[silver_bullet]

agreed

[74NovaMan]

Thanks again guys. I drove 33 miles home last night and as it warmed up on the freeway it hit about 220. It was there for maybe a minute and then started dropping and wound up around 190. It stayed around there pretty steady for the rest of the drive home. I agree with the air bubble theory for the eariler behavior but the above looks like thermostat to me.

I picked up a new radiator and another new thermostat yesterday. When I swap those out I'll drill holes and try the heater hose trick as well. I'll make sure to pick up a new cap too. Hopefully that will solve the cooling issues.

I believe that I have figured out the temp switch/light issue. When I called NAPA for a replacement sender (first one was from O'riely) the guy asks "light or gauge?" Don't remember that question from O'riely. I'm betting I have a guage sender.

I also picked up the rebuilt transmission and new converter last night. The next couple of days should be busy.

[Deaf Bob]

I read your problems with interest..
I also have that same "problem" with my flatbed... Not sure what I did to make that happen.. Might be hose replacement..Or thermostat..
It will heat up to 220/240 for a half mile or so then drop to 160/180. With a 180 thermostat..
Never lost water/coolant. Always have some in overflow and radiator.. Heater doesn't warm worth a wee! So sounds like I will try a new cap and filling with the heater hose.. Be some time before I do it as there is a cord of slabs on it right now

[STINEY]

I once cured that problem by tossing the new generic parts store thermostat (actually 3 of them) and stepping up to a STANT SUPERSTAT.

Hold one of each in your hands, there is no comparison. Cheap thermostats suck.

The STANT was about $15 at the time.

[74NovaMan]

New radiator is in. Time to get the old Trans out.

Here is a pic of the new parts:

[74NovaMan]

Trans is out!

[74NovaMan]

For the "pictures or it didn't happen" crowd:

[74NovaMan]

New stuff ready to go. Old radiator. Had to quit at 12:30 am so I could get some sleep before work. Hope to be back on the road Saturday.

[TheSilverBuick]

I'm still not convinced. You know with photoshop and all =P

[74NovaMan]

Got the transmission in today. Here are a couple of things I discovered to ease installation.

• Install the top 2 trans to block bolts with the crossmember out and the engine tilted back. The install happens from under the car this way. A 3 foot extension with a u-joint socket are helpful/necessary.
• Start the trans lines in the transmission before it is lifted into place.
• Get a 1/2" crows foot wrench for the final tightening of the lines on the trans. See pics. This worked so well I can't tell you how happy I was about it.

I checked the trans pressure and had a little panic attack when they were not quite what I had expected. I texted my trans guy and he called back and said we were good to go.

Tomorrow I need to get the engine temp under control as I appear to have air bubble issues still.

[pintoboy77]

I don't know if you have a plug or a vaccum tree on your thermostat housing or not,but on the Pinto I have a plug on mine and I remove that and take a screwdriver and push the thermostat open and fill the radiator and that does it for me. How new is the waterpump and in the past I have always had problems with flex fans and overheating on the Pinto last year I went with an electric fan and no more overheating.

[74NovaMan]

Greg - The water pump is new and unfortunately I do not have any access to the thermostat when installed. The flex fan worked fine in the past and given the temps here lately (low 70s) that is definetly not the issue at this point. Thanks for the ideas.