Brand New Radiator @Cap Leaking?

[andersonoverland]

Hey guys.

Just installed a brand new CSF radiator and its seeping out of the fill tube under the radiator cap. I’ve tried to tighten the cap flares so it seats better, but its still leaking. I tried to barely hammer down a high spot on the opening collar of the fill tube as well to ensure it was seating level. Any ideas? Should I try changing out the cap? Any way to make sure the fill tube surface is perfectly level for a good seal?

 

[mudgudgeon]

Is it a new cap already? If not try a new one

If the filler tube is smooth, no raised burrs, shouldn't need to do anything. No bending tabs or hammering, or flattening anything.

If it's not smooth and flat, it's defective IMO

 

[andersonoverland]

God I hope I don’t have to take it back out.

 

[RuggedOverland]

Swap the cap as a cheap easy first next step, if it still leaks rent a radiator pressure tester from one of the big 3, AutoZone, O'reilly, Advanced and make sure the radiator isn't cracked and go from there.

 

[Hornd]

I joke.....

Change it with OEM unless it is Different Style.

Frustrating when a Nickle Holds up $10.

 

[andersonoverland]

Swap the cap as a cheap easy first next step, if it still leaks rent a radiator pressure tester from one of the big 3, AutoZone, O'reilly, Advanced and make sure the radiator isn't cracked and go from there.

I know the radiator itself is not leaking, its just a super tiny bit around the bottom of the fill tube coming from up under the cap.

 

[JoeCova]

Does your cap actually have a rubber gasket inside of it?

 

[BILT4ME]

The OEM caps and CSF radiator tend to not like each other. Get a shytty aftermarket cap that fits better.

Not being sarcastic.

 

[RuggedOverland]

I know the radiator itself is not leaking, its just a super tiny bit around the bottom of the fill tube coming from up under the cap.

I would go with a Motorad ST13R lever vent cap, they're a great product and really prefer them

 

[CJF]

I know the radiator itself is not leaking, its just a super tiny bit around the bottom of the fill tube coming from up under the cap.

Show us some pics.

 

[andersonoverland]

Yeah its an actual CSF cap! Lol! I’ll get another one and test it out.

 

[thabruiser]

I have had several times where the overfill nipple hose was the actual source of the leak, due to a poorly fitting hose. You sound like you know what you're talking about, so if you are doubly sure it is the cap itself, then disregard me . That area has several failure/potential leak points that are so close, it can be hard to verify the source. Good luck!

 

[andersonoverland]

Got it fixed guys! Was the CSF cap! Got me a cheap duralast lever one and no leaks! Go figure!

 

[thabruiser]

Hooray! Thanks for updating us! Glad you solved the problem.

 

[ToyotaMatt]

Got it fixed guys! Was the CSF cap! Got me a cheap duralast lever one and no leaks! Go figure!

You made only 1 small error here ..

 

[andersonoverland]

Yeah now I’m chasing the headlight circuit that used to kinda work, but now I get nothing! Lol. Fun stuff. But hey at least she’s runnin!

 

[ToyotaMatt]

That Cap with the RED hand valve is a no-no bad thingy


i WILL assume its a Small Cap 4/86 - Later


the Double EPDM is what is required here


this is a Genuine NipponDenso Saudi Spec. region Commercial Grade HI-HEAT / Also Cols Spec ast the Correct 0.9 Pressure Rating

if Your Correct cap is working as it should ? why the hand Valve ? TOYOTA never used a hand valve


These work well with the CSF Brand Goose Neck , and also have the 1/2 turn De-Pressurize feature

.

 

[smritte]

When I was young (late 50's-60's) the lever caps were for the guy putting fuel in your vehicle. While your car was fueling, he would check your fluids, including your coolant. You needed the lever to vent the pressure from the hot engine. Vehicles were just starting to have reservoirs and most didn't. The advantage of that cap was it didn't let coolant in and out like the modern cap/reservoir does. They had their place, on old school vehicles with no reservoir.

 

[andersonoverland]

That Cap with the RED hand valve is a no-no bad thingy


i WILL assume its a Small Cap 4/86 - Later


the Double EPDM is what is required here


this is a Genuine NipponDenso Saudi Spec. region Commercial Grade HI-HEAT / Also Cols Spec ast the Correct 0.9 Pressure Rating

if Your Correct cap is working as it should ? why the hand Valve ? TOYOTA never used a hand valve


These work well with the CSF Brand Goose Neck , and also have the 1/2 turn De-Pressurize feature


View attachment 3797540

.
View attachment 3797548

Well shoot. Didn’t know that. This is what the guy had at autozone. I’ll buy one of these instead.

 

[ToyotaMatt]

Well shoot. Didn’t know that. This is what the guy had at autozone. I’ll buy one of these instead.

Made in Chairman MOE Spec. parts

&

Made in JAPAN Spec. parts


well ......... i am sure you understand now a bit more