badtransam97

iTrader: (5)

Just finished a cam/vlavespring swap, got about 200miles on the car. Filled radiator with 50/50 Dexcool and water. Car will idle all day around 200, and usually will cruise between 200-210. First time headed to the track(20miles), I noticed it was creeping up to around 220-225, and when I got parked, it had blown it out the overflow. So I assumed air..jacked the car up, let it run with cap off, and could see good circulation,etc..Thought all was well, and drove back home, plus about 50 more miles with no problems. Well last night headed home from the track it runs up to about 220ish and I notice it seems to only do it when around 60mph and 6th gear,so low rpm's. Seems like higher RPM's possibly help. Got home, and it hadn't blown any out of the overflow this time??? I know the fans are working bc they ran for a few seconds after turning key off. Thinking possibly still trapped air? Maybe a new cap and thermostat?? What baffles me is it runs perfect at idle, and never gets past 220 or so, then returns gradually to 200-210. Any help or ideas are appreciated!!

wssix99

iTrader: (5)

When you say "blown it out of the overflow," do you mean like an Old Faithful geyser, or did it just leak out of the top?

Where do you live? What kind of ambient temperatures are we talking about here?

badtransam97

iTrader: (5)

Well, I never actually saw it in action, but when I popped the hood I could see where it had came out. It didn't cover the whole engine bay or anything, just basically the lid area ans down by the battery tray. Temps were 65-70 OAT, and car never got over 215-225

jsteele90

iTrader: (13)

sounds like you still have some air in the system. Your seal on your radiator cap could have dried out while it was removed from the car also.

wssix99

iTrader: (5)

I'd start with a new cap, particularly if the current one has some age on it.

If your current cap isn't holding proper pressure, then it might cause excess fluid to flow to the overflow (air or no air) and could also cause the higher temps. (The system needs to be pressurized to work optimally.)

You could have the cap tested to make sure... but its probably a whole lot easier just to change it out and go from there.

badtransam97

iTrader: (5)

Thanks guys. I was kind of thinking lid for a start. AFAIK, it's the original lid, which would be 14yrs old now! Lid would be a cheap part to start with anyway. I will try to report back once I am off work and have a chance to mess with it. Thanks!