[MESOGLEA]

Our VQ40 has 2 radiator looking caps.
The one on the radiator is just a cap with a rubber seal.
The overflow has the internal spring/relief valve.
I've never seen that before. I didnt think the overflow would be part of the pressurised system.
Are my caps on correctly?

 

[ffips]

yes

 

[chaz]

if they leak they are not on tight enough,yes there are 2

 

[Clint]

Yes the cap on the radiator is only a seal. The spring loaded cap goes on the reserve bottle to pressurize.
A spring cap on the radiator will cause the truck to overheat.

Clint

 

[Zero Six LE]

The cap on the radiator is mainly there for filling the cooling system. Some full size trucks don't have the radiator cap on the radiators. They only have the pressure cap on top of the recovery tank.

 

[paris1]

Are my caps on correctly?

They only go on one way; cannot be reversed.

 

[Clint]

They only go on one way; cannot be reversed.

Not correct. There was a member who put a spring loaded pressure cap on the radiator and overheated.
The cap with the rubber seal on the radiator and the traditional cap with the spring goes on the bottle on the fender.

Clint

 

[OkieScot]

I put the chrome NISMO caps on both places and I overheated. Strangely when I first did it I didn't have a problem. Several months later I removed them and right after I replaced them I had the overheating problem.

 

[paris1]

Not correct. There was a member who put a spring loaded pressure cap on the radiator and overheated.
The cap with the rubber seal on the radiator and the traditional cap with the spring goes on the bottle on the fender.
Clint

Well I was half right. The spring-loaded cap will fit either the radiator or the expansion bottle, but the radiator cap (with rubber seal only) will not fit the expansion bottle because the tabs are too large for the slots on the bottle.