New engine running hotter

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tercle
Top Notch Member
Posts: 193
Joined: Sat Aug 27, 2011 9:57 am
My tercel:: 1985 SR5
Location: Seattle

New engine running hotter

Post by tercle » Thu May 17, 2018 11:31 am

I just installed a newer 3A engine in my SR5, and the temperature gauge says it is running hotter than the old one.
I set the timing to 9 degrees BTDC.
I purged the cooling system and it has probably 60/40 distilled water/antifreeze.
I am using the temperature sender that came with the engine, but I am going to swap the old sender in and try that.
I haven't touched the thermostat yet...
I plan to add a manual switch for the radiator fan.

Anything else I should look at?

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Petros
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Posts: 10168
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: New engine running hotter

Post by Petros » Thu May 17, 2018 1:58 pm

Replace the Thermostat, Replace the Thermostat, Replace the Thermostat, right away. when an engine sits without being run for a long time I notice the thermostat performance seems to be affected. So I always change it out on any project car or engine I get, especially if I bought it out of someones back yard where it has not been run. it is a simple part that can cause a lot of problems when they malfunction, you have an unknown age and quality t-stat in there can can wreck your engine, change it before you do anything else.

change the thermostat, not worth the risk. almost certainty that is causing the higher temp running. buy a quality one, not one made in a communist factory. Not worth the risk.

BTW, did I mention? make sure you replace the Thermostat.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

tercle
Top Notch Member
Posts: 193
Joined: Sat Aug 27, 2011 9:57 am
My tercel:: 1985 SR5
Location: Seattle

Re: New engine running hotter

Post by tercle » Fri May 18, 2018 12:02 am

Good info, as usual. Thanks.

tercle
Top Notch Member
Posts: 193
Joined: Sat Aug 27, 2011 9:57 am
My tercel:: 1985 SR5
Location: Seattle

Re: New engine running hotter

Post by tercle » Sun May 20, 2018 6:41 pm

New thermostat fixed it.
The cooling system seemed to be working OK with the old one, but it ran just a fraction hotter when it was warmed up.

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Petros
Highest Ranking Member
Posts: 10168
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: New engine running hotter

Post by Petros » Sun May 20, 2018 10:04 pm

that is how it starts to fail, it does not track and maintain temperature. the other thing that can happen is it no longer holds a steady temperature, but the temp gauge seems to drift up and down a little, as it continues to fail these temp swings get larger.

if either happens change the T-stat right away, before it completely fails. Some authorities recommend replacing the t-stat ever two years, that seems a bit excessive, but certainly the t-stat should not be run more than 4 years.

One time I needed one in a hurry and the only t-state available locally was a made in china piece of junk for only $5.99. I bought it and installed it anyway because I needed one right away. It worked okay for about 9 months, than it stated the small temperature swings. Easy to ignore, but in another month the temperature fluctuations become worse and more worrysome. I would not figure even a cheap t-stat would give up in less than a year, but I replaced it with a quality one (about $17), and the temperature swings went away. I am glad I did not ignore it any longer.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

tercle
Top Notch Member
Posts: 193
Joined: Sat Aug 27, 2011 9:57 am
My tercel:: 1985 SR5
Location: Seattle

Re: New engine running hotter

Post by tercle » Sun May 27, 2018 9:16 am

The engine is running good now. Has 83K on it. Compression is 175 175 175 175.
I was all set to adjust the valves, but they were already 008 and 012.
There is a puff of white smoke in the morning, so I bought some valve stem seals at Rockauto.

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