89 temp gauge reading high
Melting Slicks
Joined: Dec 2009
Posts: 2,236
Likes: 286
OP, did you have to use any adaptors to get the sensor threaded into the head? I'm saying this because my trick flow heads have 1/2 npt holes where the originals had 3/8 npt. I used an adaptor for my cooling fan switch but it wouldn't work, even with an extra ground wire (thinking the anodized adaptor wasn't allowing a good ground). I believe my problem was the adaptor pulled the tip of the switch out of the coolant enough that it just wouldn't hot enough. I used another switch that was 1/2 threads & it worked just fine.
Thread Starter
Racer
Joined: May 2009
Posts: 364
Likes: 3
From: merced ca
OP, did you have to use any adaptors to get the sensor threaded into the head? I'm saying this because my trick flow heads have 1/2 npt holes where the originals had 3/8 npt. I used an adaptor for my cooling fan switch but it wouldn't work, even with an extra ground wire (thinking the anodized adaptor wasn't allowing a good ground). I believe my problem was the adaptor pulled the tip of the switch out of the coolant enough that it just wouldn't hot enough. I used another switch that was 1/2 threads & it worked just fine.
Thread Starter
Racer
Joined: May 2009
Posts: 364
Likes: 3
From: merced ca
So I think I'm going to sum my problem down to one hell of an air pocket that just won't come out. I tried burping the system and a few bubbles came out and my gauge went down to 208 compared to 217. But it went back to the way it was and now won't go lower than 217 again. I tried really hard to get the air out but ain't happening. Maybe it's the design of the heads? I never had this problem with the original l98 aluminums. So I think I'm going to get that vacuum set for the cooling system. Flush and refill with the vacuum deal and call it done.
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
So I think I'm going to sum my problem down to one hell of an air pocket that just won't come out. I tried burping the system and a few bubbles came out and my gauge went down to 208 compared to 217. But it went back to the way it was and now won't go lower than 217 again. I tried really hard to get the air out but ain't happening. Maybe it's the design of the heads? I never had this problem with the original l98 aluminums. So I think I'm going to get that vacuum set for the cooling system. Flush and refill with the vacuum deal and call it done.
Still gotta ask if you really think an air pocket would cause such an internal difference? If there was air AT the dash sensor, I think it would be more "whacked". If there's an air pocket, why do you think the coolant is "normal" at the stat?
Tomorrow, the incredible Hulk is coming over. I asked him to hold the car with the nose WAAAAY up in the air while I refill it!
Seriously, if you think of it, please let me know how your vacuum fill turns out!!!!
Last edited by GREGGPENN; Aug 27, 2016 at 02:06 AM.
Thread Starter
Racer
Joined: May 2009
Posts: 364
Likes: 3
From: merced ca
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
I got the unit below and can now refill the cooling system without any air in the system at all....
....WW
https://www.corvetteforum.com/forums...ere-it-is.html
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....WWhttps://www.corvetteforum.com/forums...ere-it-is.html
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..
Last edited by WW7; Aug 28, 2016 at 06:30 AM.
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Thread Starter
Racer
Joined: May 2009
Posts: 364
Likes: 3
From: merced ca
Well I got my vacuum deal in. But I also decided to do a coolant flush because I saw brown flakes in the coolant. I bought evaporust thermocure from summit. Got very good reviews on this stuff even seen before and after pics on the review page. I'm gonna run this stuff in my motor for a week. I'm pretty sure I have rust build up in my block. I do recall taking out my knock sensor and the hole is plugged up. After that 50/50 mix and water wetter going in.
Race Director
Joined: Mar 2015
Posts: 15,926
Likes: 579
Well I got my vacuum deal in. But I also decided to do a coolant flush because I saw brown flakes in the coolant. I bought evaporust thermocure from summit. Got very good reviews on this stuff even seen before and after pics on the review page. I'm gonna run this stuff in my motor for a week. I'm pretty sure I have rust build up in my block. I do recall taking out my knock sensor and the hole is plugged up. After that 50/50 mix and water wetter going in.
if you don't pull them you will leave over a gallon of crap water in it.
Last edited by antfarmer2; Sep 1, 2016 at 07:44 PM.
Le Mans Master
Joined: Aug 2007
Posts: 8,735
Likes: 412
From: WV
Thread Starter
Racer
Joined: May 2009
Posts: 364
Likes: 3
From: merced ca
Well it's been a few days since I put that thermocure flush in my cooling system. I'm waiting for my next day off before I flush it all out. I have to say it must be doing something I took my cap off and have some crud floating in my radiator. And I'm sure it's from the block. My radiator isn't that old. And I also noticed my temps are going down a bit lower. Down to about 206 when driving on the highway. Versus 215.
Last edited by kitttransam; Sep 4, 2016 at 01:29 PM.
