Coolant overflow puking-89A4
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From: altered state
St. Jude Donor '05
Well, took CFI's advice and ran the motor to 2000 rpm this morning w/thermostat open, topped off coolant til it was full and stuck the cap on. I took the overflow cap off, and at about 170 shut the motor off, no overflow at all. No drops (visible anyway) lost today. Ill have to pressurize the system sometime this weekend if I get a minute. Sure would like to know what the root of the problem is.
Safety Car
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From: The Pines South Jersey
Originally Posted by MrNuke
On an LT1, yes, on an L98 I dunno.. My '85 had the original cap for 21years.. Never any problems.
I run a 13lb cap with a 180 stat and havent had a problem for the last year - and I drove it about 400 miles the weekend of the OC Boardwalk Bash.
Le Mans Master
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Originally Posted by CFI-EFI
ABSOLUTELY not!
If that's what you mean I say, and you can quote me, "ABSOULTELY NOT."
Here is MY suggestion, do a exhaust gas test of the coolant. If your overfull keeps overfilling I doubt your problem is as simple as a bad radiator cap.
Burning Brakes
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From: Where's Lunch?
Originally Posted by CentralCoaster
Why?
7 lb cap will lower your boiling point.
7 lb cap will lower your boiling point.
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From: altered state
St. Jude Donor '05
Wwll, 2 days later and appears to be leaking from same place, due to car movement?
I took the reservoir cap off when I got in tonight, was wet around it....COolant inside was cold, turned car off and let it sit, nothing pusing out. No coolant in oil, wtf? Radiator itself still dropping level, where the heck is it going? Bad cap?
I took the reservoir cap off when I got in tonight, was wet around it....COolant inside was cold, turned car off and let it sit, nothing pusing out. No coolant in oil, wtf? Radiator itself still dropping level, where the heck is it going? Bad cap?
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From: San Pedro CA
Originally Posted by hippy
Absoultely not what? That's kinda vague as a few things have been thrown out there. Is it absolutely not that a 16 lb cap would make a difference to a 15 lb cap?
If that's what you mean I say, and you can quote me, "ABSOULTELY NOT."
If that's what you mean I say, and you can quote me, "ABSOULTELY NOT."
Here is MY suggestion, do a exhaust gas test of the coolant. If your overfull keeps overfilling I doubt your problem is as simple as a bad radiator cap.
Also, pull the plugs. They are the one thing that will give you an inside view of the combustion chamber.
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From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
Originally Posted by cuisinartvette
I just bought a 16 lb cap from Vatozone awhile back now that I think about it and thats when the "losing thing started".
In fact, later that same day after pulling in the DMV parking lot the lower radiator hose blew off-Came out from my appointment to find the entire ground area around the car doused in coolant ....COuld a defective cap cause that kind of pressure?
In fact, later that same day after pulling in the DMV parking lot the lower radiator hose blew off-Came out from my appointment to find the entire ground area around the car doused in coolant ....COuld a defective cap cause that kind of pressure?
So, what you're saying is that if you go from stone cold in the morning and take a look at the plastic overflow tank, the level stays the same after the car's been driven and you stop somewhere. Come back out, still same level. Go home, level never changes but coolant comes out new cap.
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Melting Slicks
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From: St. Charles, MO Route 66 Corvette Club
Do you know anyone with a radiator pressurizer tool? I used to lose hair trying to find leaks (and I cannot afford to lose any hair) and finally bought one of the devices from NAPA. Not cheap, but sure finds leaks! 
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From: altered state
St. Jude Donor '05
Originally Posted by LT4CompYell
Well if it was a new 16lb cap and it was defective, hmmm, could be. What if it wasn't opening until say, 25lb? That might account for the hoses blowing off, and it might even for the push back through the cap.
So, what you're saying is that if you go from stone cold in the morning and take a look at the plastic overflow tank, the level stays the same after the car's been driven and you stop somewhere. Come back out, still same level. Go home, level never changes but coolant comes out new cap.
So, what you're saying is that if you go from stone cold in the morning and take a look at the plastic overflow tank, the level stays the same after the car's been driven and you stop somewhere. Come back out, still same level. Go home, level never changes but coolant comes out new cap.
The bit about the rad. cap not opening til 25 lbs (+-)makes sense. Lots of pressure in that rad.
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From: San Pedro CA
Originally Posted by hippy
WTF is the oil heater? AND, who was yelling?
I wasn't picking on you... it was the phrase "absolutely not" in bold caps that I was picking on.
Le Mans Master
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Originally Posted by bogus
the oil filter housing on the L98 has this thing that coolant passes through... I guess it keeps the oil closer to engine temps... all I know is that it could be a leak cause.
I wasn't picking on you... it was the phrase "absolutely not" in bold caps that I was picking on.
I wasn't picking on you... it was the phrase "absolutely not" in bold caps that I was picking on.
I was trying to convey my opinion that "absolutely not" was how I felt.
That little housing by the filter with coolant running thru it is called an earl cooler. It isn't there to heat the earl up but to cool the earl down.
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
My earl cooler helps heat my engine oil during warmup.
I should be more clear. A 7 lb cap will reduce your boiling point, compared to the stock 17 lb cap. I wouldn't feel comfortable with a 235 boiling point, when the fan comes on at 228. And I guarantee that 228 at the temp sender doesn't mean it's not hotter somewhere else in the system.
I should be more clear. A 7 lb cap will reduce your boiling point, compared to the stock 17 lb cap. I wouldn't feel comfortable with a 235 boiling point, when the fan comes on at 228. And I guarantee that 228 at the temp sender doesn't mean it's not hotter somewhere else in the system.
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From: altered state
St. Jude Donor '05
Racer
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From: Buffalo Grove IL
Originally Posted by Jerris
...or the hose to the overflow has a hole. If this happens the radiator pulls air in as it cools not the coolant from the overflow.
The recovery tank setup on the 'Vette is different from the Trans Am, so I'm not sure where the most likely place for an air leak would be. Still, I'd check it out as best as you can as your symptoms were exactly what I was experiencing.
Good luck!
Ben
Burning Brakes
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From: Where's Lunch?
Originally Posted by CentralCoaster
My earl cooler helps heat my engine oil during warmup.
I should be more clear. A 7 lb cap will reduce your boiling point, compared to the stock 17 lb cap. I wouldn't feel comfortable with a 235 boiling point, when the fan comes on at 228. And I guarantee that 228 at the temp sender doesn't mean it's not hotter somewhere else in the system.
I should be more clear. A 7 lb cap will reduce your boiling point, compared to the stock 17 lb cap. I wouldn't feel comfortable with a 235 boiling point, when the fan comes on at 228. And I guarantee that 228 at the temp sender doesn't mean it's not hotter somewhere else in the system.
I would suppose if I lived in Arizona, the 7lb. cap may be marginal, but as I said in an earlier post, even in 90+ degree weather here in MI, I have no boil out problems with a 7 lb. rad cap.
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From: altered state
St. Jude Donor '05
Well, I exchanged the new cap for another and changed the hose on the overflow, had a slight kink to it, not bad though.
Pressurized the system to a little over 20 lbs, lost maybe 1 lb in a 10-15 min span and held.
See how it goes from here.
Getting the oil changed tonight, Ill check for water in the oil . PCV, oil fill, dipstick, etc shows no signs of moisture at all.
Ill start pulling plugs, etc soon as I get my DD back-Hopefully next week.
Pressurized the system to a little over 20 lbs, lost maybe 1 lb in a 10-15 min span and held.
See how it goes from here.
Getting the oil changed tonight, Ill check for water in the oil . PCV, oil fill, dipstick, etc shows no signs of moisture at all.
Ill start pulling plugs, etc soon as I get my DD back-Hopefully next week.
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From: joplin mo
if you still have the cooling system pressure tester you may be able to spot a bad head gasket by installing the pressure tester and warming the car up until the tstat opens then pressurizing your radiator to around 15lbs and watch the needle on the tester while the engine idles if you have a blown head gasket you should see the needle spikeing when the adjacent cylinder fires.not a final test but a quick indicator
john
john
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From: altered state
St. Jude Donor '05
Originally Posted by redazz
if you still have the cooling system pressure tester you may be able to spot a bad head gasket by installing the pressure tester and warming the car up until the tstat opens then pressurizing your radiator to around 15lbs and watch the needle on the tester while the engine idles if you have a blown head gasket you should see the needle spikeing when the adjacent cylinder fires.not a final test but a quick indicator
john
john