3A-U motor.

General discussion about our beloved Tercel 4WD cars
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Idago
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Joined: Mon Aug 01, 2022 4:51 pm
My tercel:: 84, lifted, Weber, low miles 475,000...

3A-U motor.

Post by Idago »

I bought tercel parts car that has a 3A-U motor. It spins over and probably is serviceable. Apparently a Japanese version. Probably a replacement motor. Online research says it's 83 HP but still a 1.5 liter. Does anyone know more about this motor? I plan to swap it in to a tercel soon and get it running again. I will just use the long block and my own peripherals.
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dlb
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My tercel:: '87 sr5, '83 dlx parts car
Location: bc, canada

Re: 3A-U motor.

Post by dlb »

I am very confident it is not 83 hp. That is likely a typo, or maybe someone trolling. It's possible the 'swirl' engine was 1 or 2 hp higher than the regular 62 hp 3a but by and large, 3a's are only 62 hp.
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Mark
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My tercel:: 1984 Automatic, 1981 sedan
Location: Victoria, B.C.

Re: 3A-U motor.

Post by Mark »

According to Wikipedia, there are several versions of the 3A engine, all with different horsepower at different rpms and different torques. I always assumed that the higher horsepower ones lacked the horsepower-killing emissions requirements of the North American ones, but maybe they have different camshafts for different torque profiles or something. https://en.wikipedia.org/wiki/Toyota_A_engine
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Nordical25
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Joined: Tue Feb 08, 2022 11:49 pm
My tercel:: 2 4wd 1987's. One with 4a, other with 3a
Location: Finland

Re: 3A-U motor.

Post by Nordical25 »

3A-U motors can have also different carbs & intake manifolds, which affect also engine power.

I have also discovered that European and American Tercels have different weights and springs in distributor. I wonder if distributor internals can affect also power.
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: 3A-U motor.

Post by Petros »

most of the JDM 3a engines had a duel SU carb set up, and I suspect a different cam profile as well as totally different emissions system (not as restrictive). I would love to get my hands on the JDM duel carb and manifold set up.

I am just about done chasing my tail with the USDM emissions/fuel systems. as mine age, more and more parts stop working correctly. some I can remove or by pass, but some must be working properly for the stock USDM carbs to run properly. Although when working properly I like the factory set up, it is economical and fairly reliable, but my whole fuel/emission system parts are coming up on about 400k miles, and 40 years old. I keep replacing the parts I can get or have spares for, but many of the parts are NLA, and these cars are getting rare at the wrecking yard these days. I likely will be doing a full EGR delete this weekend, and I will have to get the choke working properly before this winter, I have it rigged to stay open all the time now (cold starts are a bit annoying, but runs after warmed up).

I keep thinking there must be a better fuel system to switch to that is not too costly, has good drivablty and gets good economy. the after market EFI kits are just too costly, and none I have seen can are plug and play. all take a lot of fine tuning.
'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)
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