Radiator cap problems?

[Beave]

My radiator cap was leaking and getting coolant on my engine so i got a new one to replace it (small cap on the radiator not the overflow tank). WEll i changed it and all was fine until today i notice the truck getting hot, popped the hood and the overflow tank was to the top with coolant, cracked the cap open and it went down to the normal level. So i started the truck up with the caps off and added water to it, not much just a little until it quit bubbling, i figured it had air in the system. I drove it around for about 20 mins and it didnt overheat. Has anyone else had this problem or think i just had air pockets causing this?

[TitanBlue]

What cap did you get? OEM or a Stant with a spring in it?

It needs to be a plain cover, not spring type cap. Caps have been a problem due to bottom edge clips not holding them on tight, or some think their hood actually touches the cap a bit and puts pressure on it that causes a leak. Search for more experiences. See bottom of screen.

[HudsonValleyTitan]

Originally Posted by Beave

My radiator cap was leaking and getting coolant on my engine so i got a new one to replace it (small cap on the radiator not the overflow tank). WEll i changed it and all was fine until today i notice the truck getting hot, popped the hood and the overflow tank was to the top with coolant, cracked the cap open and it went down to the normal level. So i started the truck up with the caps off and added water to it, not much just a little until it quit bubbling, i figured it had air in the system. I drove it around for about 20 mins and it didnt overheat. Has anyone else had this problem or think i just had air pockets causing this?

Go to the dealer. There's a TSB on the caps. They'll replace it with a newer design for free.

[Titan06RX1]

Originally Posted by HudsonValleyTitan

Go to the dealer. There's a TSB on the caps. They'll replace it with a newer design for free.

My dealer "Simmons-Rockwell" told me today that there wasnt a TSB on my radiator cap (06 SE KC 4x4). They still ordered me a new cap but they were not sure if it was any different from the one i already had. Anyway i can prove them wrong?

[37L1]

Here's the TSB HVT was referring to:

http://www.nissanhelp.com/Ownership/.../NTB04-018.htm

[Titan06RX1]

Originally Posted by 37L1

Here's the TSB HVT was referring to:

http://www.nissanhelp.com/Ownership/.../NTB04-018.htm

Thanks 37L1.

They put a new radiator cap on the truck today, the only difference I noticed is the sticker on top of the radiator cap was yellow and the new one is orange. Other wise they look identical.

[Beave]

i had to buy my cap, they told me there is no tsb on them, i argued for a second then before i got too pissed i just paid the $13 and got a new one, problem fixed.

[Juday]

I had the same problem with the radiator cap Beave. It sprayed all over my engine compartment leaving coolant stains all over the place. It seemed to happen under high acceleration more than anything else. I took it to the Nissan dealership to see what the problem was and he said it was a bad cap and replaced it at no cost to me. Since the new cap, I have had zero problems. So my advise, go to your dealer and get a new one.

[zcajun68]

my 06 titan was also leaking from the cap. i had this problem since it was new, dealer changed radiator thermo housing cap a couple of times. well finally yesterday i took it back in for the same prob. at 49,000 miles and the tech put a glass tube with purple liquid in it on top of the radiator and mashed the accel bubbles came up and it turned green, he looked at me and said a head is cracked. i only had spray from the cap at high rpms like 5200

[HudsonValleyTitan]

Originally Posted by zcajun68

my 06 titan was also leaking from the cap. i had this problem since it was new, dealer changed radiator thermo housing cap a couple of times. well finally yesterday i took it back in for the same prob. at 49,000 miles and the tech put a glass tube with purple liquid in it on top of the radiator and mashed the accel bubbles came up and it turned green, he looked at me and said a head is cracked. i only had spray from the cap at high rpms like 5200

I think he's FOS. If the head was cracked, you'd be blowing white smoke out of the tailpipe. You'd certainly know about it by now. What he saw in the radiator will happen anytime you hit the gas with the cap off.

[zcajun68]

my cap was leaking so i took it in and they did a test on the radiator with some puple fluid in a glass tube and when they gas the gas the glass bubbled and turned green the guy said i have a cracked head. a new head is on the way. 53000 miles

[Yahooligan]

Originally Posted by HudsonValleyTitan

I think he's FOS. If the head was cracked, you'd be blowing white smoke out of the tailpipe. You'd certainly know about it by now. What he saw in the radiator will happen anytime you hit the gas with the cap off.

It's hard to fake a failed head gasket with the purple stuff, it turns green not because of the bubbles (Coolant shouldn't bubble) but because of the exhaust gas, it's a chemical reaction. Air in the system won't turn it green.

It's on Nissan's dime anyway, so if they want to replace the head then I don't see what that problem is.

A failed head gasket doesn't always result in coolant entering the exhaust and steam coming out, it depends on where the gasket failed. If it's between two cylinders then often times you'll get the steamy exhaust and coolant smell out the exhaust pipe as the compression and ignition strokes force coolant into the neighboring cylinder , but if it fails on the side of a cylinder then there's not really any suction or enough pressure for the coolant to enter the combustion chamber in any large volume, but you will get exhaust gasses in your cooling system as it is forced out during both compression and ignition cycles.

The purple stuff is a good way to find out if this is happening and you can also use an exhaust gas analyzer to "sniff" the coolant with the radiator cap off. Not by submerging it, but keeping it right above the neck you can often get a reading.

[TitanBlue]

Now that is some good info to know. I wish we had more info with that depth. Thx yahooligan.

[HudsonValleyTitan]

Originally Posted by Yahooligan

It's hard to fake a failed head gasket with the purple stuff, it turns green not because of the bubbles (Coolant shouldn't bubble) but because of the exhaust gas, it's a chemical reaction. Air in the system won't turn it green.

It's on Nissan's dime anyway, so if they want to replace the head then I don't see what that problem is.

A failed head gasket doesn't always result in coolant entering the exhaust and steam coming out, it depends on where the gasket failed. If it's between two cylinders then often times you'll get the steamy exhaust and coolant smell out the exhaust pipe as the compression and ignition strokes force coolant into the neighboring cylinder , but if it fails on the side of a cylinder then there's not really any suction or enough pressure for the coolant to enter the combustion chamber in any large volume, but you will get exhaust gasses in your cooling system as it is forced out during both compression and ignition cycles.

The purple stuff is a good way to find out if this is happening and you can also use an exhaust gas analyzer to "sniff" the coolant with the radiator cap off. Not by submerging it, but keeping it right above the neck you can often get a reading.

Good to know. Thanks

[sterlinator]

i had the same problem with my '04. i took it to the dealer (twice) and they told me that they did a pressure test and the cap was good. the advisor then told me that i shouldnt take the cap off while the engine was hot. why would i take the cap off, fluid go everywhere, and then take it the dealer for a leak? ive since traded it in, but its good to know that there was something actually wrong with it and i wasnt going insane.