Engine Temp spike and very quick drop
Thread Starter
Intermediate
Joined: Oct 2013
Posts: 32
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Engine Temp spike and very quick drop
think thermastat but thought I should check with the brain set since I'm pretty new to C3's.
out driving last night, decided to really get on it in second taking it up to about 5000 rpm's. temperature spiked from about 160 to about 220 with in 60 seconds. then back again in another 120 seconds.
this is after it having sat for about 9 months waiting for me to get off my fat a$$ and put the rear end back in.
what thinks the brain trust?
thanks
out driving last night, decided to really get on it in second taking it up to about 5000 rpm's. temperature spiked from about 160 to about 220 with in 60 seconds. then back again in another 120 seconds.
this is after it having sat for about 9 months waiting for me to get off my fat a$$ and put the rear end back in.
what thinks the brain trust?
thanks
Thread Starter
Intermediate
Joined: Oct 2013
Posts: 32
Likes: 0
Thread Starter
Intermediate
Joined: Oct 2013
Posts: 32
Likes: 0
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Melting Slicks
Joined: May 2012
Posts: 2,192
Likes: 343
From: Allenton Wisconsin
My 69 was doing the same, not quite so severe. Changed the thermostadt and haven't noticed that symptom since. It was like when the engine was warming up the thermostadt stayed shut a little to long. T
Thread Starter
Intermediate
Joined: Oct 2013
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ok pretty inexpensive things.
1. replace thermostat
2. replace lower rad hose
3. fill cooling system with front off the ground
i can do those things.
about the lower radiator hose collapsing. seems the only way for that to happen is for a vacuum to be pulled at high rpm's as 63split63 said. the only way that happens is if the hose is really bad or the radiator itself is not flowing as it should. geez, i hope its the hose.
1. replace thermostat
2. replace lower rad hose
3. fill cooling system with front off the ground
i can do those things.
about the lower radiator hose collapsing. seems the only way for that to happen is for a vacuum to be pulled at high rpm's as 63split63 said. the only way that happens is if the hose is really bad or the radiator itself is not flowing as it should. geez, i hope its the hose.
Thread Starter
Intermediate
Joined: Oct 2013
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Drifting
Joined: Mar 2011
Posts: 1,347
Likes: 121
From: Kernersville NC
Slight rise in temp is normal. If I go through the gears hard I will get about 1-2 needle widths rise. It will return to normal in a minute. Normal for me is is 180 with an aluminum radiator. You didn't say what radiator you have so a bit higher rise might be normal for you. If it did not do this in the past and is a new issue, check, squeeze, the bottom hose to see if the spring is there. Replace hose and spring if it is missing and if you remove or change the thermostat, you can drill a small hole (1/16"-3/32") in the flange to help air purge during the initial start up.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Drill 3 1/8-3/16 holes in the skirt of the new stat, that allows a bit extra water on the flow, so engine runs more consistent on temps.....
new stats have smaller openings to restrict the water flow a bad, it's an EPA thing.....only choice is to drill some holes....
new stats have smaller openings to restrict the water flow a bad, it's an EPA thing.....only choice is to drill some holes....