Hello all, I am newly registered to the forum, but have been lurking since the beginning of the year. I don't have too much experience wrenching on my truck aside from doing some small maintenance, but I am interested in learning.
I recently had a blown head gasket on my '89 4 Runner, SR5, 5 speed manual EFI, and just got it back this morning. The problem I come to all of you with is one of the things that I noticed compared to how it ran before all of the repair work was done on it, was that it would run much cooler and the temp gauge in the dash being just a bit (3/8") above the bottom temperature line. After I got it back and drove it through town to my house, and then later to school and back (on the freeway @ 65mph), the temperature gauge has been sitting steady a little below halfway.

I am wondering if that is normal right after a head gasket change, or if it could be the valves/timing. the shop I took it too told me that I will need to bring it back in 300 miles to have the valves/timing adjusted. Could it be that, or from all of the other parts that they put on it (new head, my old one was cracked, used exhaust manifold, and timing chain cover) they also replaced the thermostat as well.

I can post pictures if that helps at all, but I'm not sure since everything is put together now.

If there is any other info I might need to put, let me know.

Thanks for the help!

 

They probibly used a different temp thermostat then what you had before. Mine sits just before halfway on the guage at running temp. But then again the factory temp guages are iffy at best.

 

Might be an aftermarket one, like the NAPA thermostat they installed in mine after the HG replacement. My 3.0 wouldn't get up to operating temperature. So we swapped the NAPA out for a Toyota, and the temp went right up.

 

Welcome.

You don't say what engine you have (you should put it in your sig) but I'm going to guess it's a 4cyl because you mention timing chain.

Normal operating temp according to the stock Toyota guage is a hair to the left of center.

 

I have the same problem, and now that it is cold here, the heat gets real hot until the thermostat opens then the temp guage drops to in between half and cold. Should I use another thermostat, because once the motor gets to temp the air the heater blows out it luke warm and not really effective.

I know this is a little off the original thread, but it is somewhat relevant.

 

Thats why you should always get a thermostat with a little valve to let fluid get by or drill a small hole in it to do just that. Allows things to warm up correctly