[Unner]

Hey everyone. I plan to flush the coolant (no problems, just want to change it) in my 2001 4Runner 4WD Automatic and was going to replace the radiator cap at the same time, just because it's cheap and easy. I know in my other car I flushed the coolant and then a few days later the radiator cap went and I had to replace it too. I guess the constant taking off and putting on was enough to mess up the seal.

Anyway, I went to the Toyota Dealer and picked up an OEM radiator cap. The one on my truck is rated for 1.1 bar and the one that the dealer gave me is rated for 0.9 bar. I asked the parts guy about it and he said that the 1.1 bar part number had been superseded and the 0.9 bar was correct.

Anyone think or know if I will have any issues running the 0.9 bar cap on my 01 even though the original one was 1.1 bar or is this unadvised?

Should I just keep running the 1.1 bar one on and keep the 0.9 in the truck just in-case, or just throw the 0.9 bar cap on and not worry about it?

Thanks in advance for any help!

[Darwinian_Crusader]

I'd just take the dealers word for it. Keep the old one just in case you do happen to run into issues though. If you are that worried about it, just keep a close eye on your temp gauge for the first few drives.

[TheDurk]

The 0.9 is p/n 16401-72090 and is listed for v6 ´99 and earlier 3G 4Runners. The 1.1 is p/n 16401-62100 and is listed for v6 ´00-´02. As far as I can tell, neither has been superseded and both are available.

That said, I doubt it makes any difference. But if one WERE superseded, you would think it would be the 0.9 which was used on older models. I would not trust anything a dealer counter guy tells me, unless he shows me the screen or I can confirm it myself.



You can see the bar number stamped on the right hand tab.

[Drcoffee]

If you look it up on rockauto.com, all the caps are rated at 13#. I would defer to the lower pressure cap. You dont want to over pressurize the system.

* Which ever cap you choose, make sure it has a brass rivet holding it altogether. I have had two different rad caps break because the spring was secured with a plastic rivet. Pisses me off that these auto patrs companies will sell a $5 part that puts your $5,000 engine at risk of failure.

[Unner]

Thanks for the input. I may just run the 0.9 one and keep the 1.1 one in the truck just in case. The invoice he printed off for me did say something about the part number being superseded, but I think it may be more like if they don't have the 1.1 bar one in stock, then it is OK for them to use the 0.9 bar one instead. Not really superseded, but interchangeable. From what I can tell the 1.1 one is still available so I think that must be it.

[TheDurk]

Originally Posted by Drcoffee

If you look it up on rockauto.com, all the caps are rated at 13#. I would defer to the lower pressure cap. You dont want to over pressurize the system.

* Which ever cap you choose, make sure it has a brass rivet holding it altogether. I have had two different rad caps break because the spring was secured with a plastic rivet. Pisses me off that these auto patrs companies will sell a $5 part that puts your $5,000 engine at risk of failure.

If he has a 2001, and the factory spec was and is 1.1 bar, why would you go to a lower pressure cap? It´s only a 20% difference; it´s not going to explode something.

[nevada]

Originally Posted by Drcoffee

If you look it up on rockauto.com, all the caps are rated at 13#. I would defer to the lower pressure cap. You dont want to over pressurize the system.

* Which ever cap you choose, make sure it has a brass rivet holding it altogether. I have had two different rad caps break because the spring was secured with a plastic rivet. Pisses me off that these auto patrs companies will sell a $5 part that puts your $5,000 engine at risk of failure.

there is a pretty big difference between .9 and 1.1 bar.

.9 is closer to 13lbs, and seems very low to me. 1.1 is closer to 16lbs, and is what I see more often.

if the system was previously working with the 1.1 cap, I would want to replace it with the same rating.

[Drcoffee]

Well, call around to other toyota dealerships to confirm the correct pressure rated cap. Thats what I would do. There would be no harm going to .9 bar. The flip side, the 1.1 bar cap is rated to max out at 18 psi. Which on an old vehicle might stress out hoses and old radiators.

Its not unusual for toyota to change specs internally and not share it with the aftermarket parts makers.

[Drcoffee]

Originally Posted by Unner

Thanks for the input. I may just run the 0.9 one and keep the 1.1 one in the truck just in case. The invoice he printed off for me did say something about the part number being superseded, but I think it may be more like if they don't have the 1.1 bar one in stock, then it is OK for them to use the 0.9 bar one instead. Not really superseded, but interchangeable. From what I can tell the 1.1 one is still available so I think that must be it.

Just check the resevoir peridically after running a while and see if you are moving too much fluid into the res. i seriously doubt it will, but that would be the only result of a .9 bar cap.

[19963.4lsr5]

That metal disk is not a rivet to hold it together it's the vent portion of the cap. It's loose cold to allow any air trapped to be pushed to the expansion tank. As the water expands from being heated the water will push into the plastic tank. When hot coolant starts going by the disk it tightens up and seals off the cap.

[SURF RUNNER]

I was thinking about getting the TRD radiator cap. Other than the obvious issue (price) is there any reason not to do this?

TRD Radiator Cap Type N 1.3 kg/cm 18.5 psi PTR04-00000-03

[Drcoffee]

So I bought a new radiator cap for our sienna 2008 today. Here is what the OEM cap looks like diassembled. The plastic valve is crimped into the cap. Once the plastic fatigues, it fails.



The back side of the secondary valve (return valve) is a plastic post with a push nut holding it place.


The new radiator cap is all metal where its needed. The only thing not metal is the gaskets. The secondary valve in the center is brass and the primary valve is stainless steel, crimped in place by a stainless steel cup.


Again, I have had two OEM style caps fail entirely dumping the valve and spring right into the radiator. For $6 at Advance Auto parts, its cheap insurance.

BTW if you dont know this, you can buy parts on their website, save 20% by using code P20 and then drive to the local store to pick it up.

[coues7]

I need to resurrect this thread as it has everything in it to answer my question. My OEM (Toyota) radiator cap broke this weekend. The only thing I can find is the spring. The spring was in the neck, but all the other parts are missing. Do I need to locate them all? What exactly is missing? Based on the pics, a bunch of rubber pieces as well as the rivet are MIA.

Thoughts?

[cashmoney]

Flush the system and buy a new cap.

[coues7]

Originally Posted by cashmoney

Flush the system and buy a new cap.

The missing pieces should be in the top of the radiator correct? The only thing I can think to do is to remove the thermostat and see if any of hte parts made it that far. I also have a tiny camera for boiler tube inspections that I can feed in from the top to see if the parts are up there.