The other day I was comeing up I-85, in the fast lane, my speedo said I was doing about 83 but it is about 5 mph slow because I have taller tires on the back so I was probably doing more like 86 mph. I had been running between 75 and 85 for about 30 minutes and had this shiney new Yellow Corvette rideing my a$$. All a sudden I started smelling anti freeze and started seeing it come up and blow out between the driverside fender and the hood seam. After about 15 seconds of this anti freeze blowing out the shiney new Corvette turned on his windshield wipers ( ) and got into the next over lane and (finnally) blew my doors off. He had to be doing over 100. This has happend several times now and only happens when I'm running 75+ mph. Is there anyway to make it not do this? I have a 6 blade fan and shroud. Maybe I should just add a catch can? Nah, its kinda funny to see the people rideing your a$$ turn their windshield wipers on. Do I need a new radiator cap or what?
We'll need a little more info. What temp is your gauge reading when you first start to boil over? If operating temps are normal then you can have the cap tested to see if it's pressure rating is accurate. But first you have to know if you are over-heating or not.
That shouldn't be hot enough for a boil over. In that case, have the cap pressure tested. It might be opening at a much lower temp and pressure.
Does it cost anything to have it tested? When I go to buy a new cap, what should I get? It's a '74 250 I6. Thanks.
Shuck's and other parts joints might have a tester. Radiator shops do, but they might charge small fee. You'll have to call around first locally to see who has the tester. Go with the stock cap at first (probably btw 11-14 lbs). I'm running a 7 pounder for less stress on the system, but I have a puke can and am running some Water Wetter which seems to drop the temp another 6-8 degrees. If a person has the loot, they could try 40 Below made by Pro-Blend, but it takes 2 cans and is more pricey.
