engine running hot and dieseling

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applewew
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Posts: 58
Joined: Sun Dec 11, 2011 1:38 pm
My tercel:: 1985
Location: No

Re: engine running hot and dieseling

Post by applewew »

Hello everyone, great to be back!

Update:

A few days later I had issues with the transmission, it was literally hard to shift and had to do stupid things to get home.

While checking the next morning, we found oil in the radiator cap. Long story short, the head gasket was shot, and the cylinder was in a very less than ideal state (see the pictures below). I'm glad the transmission issue happened, it was cheap fix by the mechanic, and got the perfect excuse to check most of the engine. Even with the awful state of the cylinder head (the machine shop added aluminum and then resurfaced), the cylinders (and compression) are in very good shape. Some rotten water outlets, but overall, good shape. I also got the carburetor rebuild kit here, but I still need a TVSV, if anyone has an extra one, I'd love to buy, so I can finally have all the vacuum system fixed.

And, the pics:
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Petros
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Posts: 11941
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: engine running hot and dieseling

Post by Petros »

wow, looks like a lot of corrosion, make sure your head ground strap is properly attached and the grounds are good. also recommend replacing the exhuast valves with new ones since the head is off anyway. They have a limited life and regrinding the face shortens their life, best to just replace them, they do not cost much.

I have several TVSV spares, where are you located? I would have to verify they work poroperly, but I would be happy to sell you one.
applewew
Advanced Member
Posts: 58
Joined: Sun Dec 11, 2011 1:38 pm
My tercel:: 1985
Location: No

Re: engine running hot and dieseling

Post by applewew »

Petros wrote:wow, looks like a lot of corrosion, make sure your head ground strap is properly attached and the grounds are good. also recommend replacing the exhuast valves with new ones since the head is off anyway. They have a limited life and regrinding the face shortens their life, best to just replace them, they do not cost much.

I have several TVSV spares, where are you located? I would have to verify they work poroperly, but I would be happy to sell you one.
Hey Petros,

The head is back on the engine now, but sure will replace the exhaust valves.
Last edited by applewew on Tue Aug 31, 2021 10:00 pm, edited 1 time in total.
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Petros
Highest Ranking Member
Posts: 11941
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: engine running hot and dieseling

Post by Petros »

I will have to check the many boxes and cans of spare parts, but I likely can locate two for you.

If the head is back on, how are you going to replace the exhaust valves, pull the head back off? If it is not all assembled it might not be too bad a job. When I rebuilt my engine, I burned first one, and than two exhuast valves within a year. A real problem, so I replaced all 4 when I pulled it off again to fix it. Also, set your spark timing at 10 deg BTDC rather than the 5 deg factory setting, it will cool the exhaust temp and make the valves last longer. Also improves economy and power a bit too.
applewew
Advanced Member
Posts: 58
Joined: Sun Dec 11, 2011 1:38 pm
My tercel:: 1985
Location: No

Re: engine running hot and dieseling

Post by applewew »

Yeah, I will pull it off again when the parts arrive. They usually take ~15 days from the U.S.

I'm waiting to have the TVSV to fix all the vaccum system (see: https://tercel4wd.com/forums/viewtopic.php? ... 723#p58723 ) and tune the timing as you recommend.

Please let me know if you find them!
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