Radiator cap

Topic: Radiator cap (Read 1272 times) previous topic - next topic

Radiator cap

December 29, 2020, 10:53:25 am

My radiator cap needs to be replaced. MOT recently replaced my original? with one that I am unhappy with. It leaked. Long story short..... please help me as to size/ pressure rating and brand, or where I should look to buy a good one.
Remember..... I'm in Mexico, but there are Autozones, truck supply etc here.
Thanks for the help

Re: Radiator cap

Reply #1 – December 29, 2020, 11:24:15 am

Any radiator shop, truck shop, NAPA or Autozone in Mexico should be able to supply a good cap. Make sure the overflow tube right at the cap has not come unsoldered. The hose to the plastic reservoir comes off the tube. Ours did and leaked coolant. Easy to DIY or a Mexican radiator shop will fix it.

Probably a 14 psi cap. The rating should be on the cap or xref the part number.

Pierce

Re: Radiator cap

Reply #2 – December 29, 2020, 11:48:42 am

So... standard size?
Nothing "special?"

Re: Radiator cap

Reply #3 – December 29, 2020, 12:00:04 pm

Look at the tank where the cap seals and make sure the "leak" is not coming from a problem there.Did it leak one time or does it
always leak?

Re: Radiator cap

Reply #4 – December 29, 2020, 12:28:47 pm

Quote from: GleamB – December 29, 2020, 11:48:42 am

So... standard size?
Nothing "special?"

I replaced ours with a generic cap, nothing special.

Pierce

Re: Radiator cap

Reply #5 – January 02, 2021, 08:45:46 am

You need a truck radiator cap, not a generic one. I found one at a truck NAPA.

Re: Radiator cap

Reply #6 – January 02, 2021, 10:52:44 am

Quote from: amos.harrison – January 02, 2021, 08:45:46 am

You need a truck radiator cap, not a generic one. I found one at a truck NAPA.

I just used the number off the OEM cap and went to a car parts store. How would a truck vs car cap be different with the same part number?

Pierce

Re: Radiator cap

Reply #7 – January 02, 2021, 11:11:54 am

Pierce, the later years went to a larger diameter cap.

Re: Radiator cap

Reply #8 – January 02, 2021, 11:19:17 am

Quote from: craneman – January 02, 2021, 11:11:54 am

Pierce, the later years went to a larger diameter cap.

I can understand that but if you take the existing OEM cap you have installed, take the part number off of it, the replacement has to be an exact fit. When I said generic, I went into the part store and didn't care if it was a Stant, Gates, Sinopharm, etc, just as long as the xref indicated it had the same specs. In other words, no brand preferred.

The fact that the later radiator tanks have a larger diameter neck has no bearing on the cap your coach has.

Is there anyone here that would not take their old cap into the parts store or at least copy the number (smart phone photo) and take that with them?

Pierce

Re: Radiator cap

Reply #9 – January 02, 2021, 11:33:44 am

I was only pointing out it is a truck, not auto cap. They won't be available at Autozone etc. Napa can get it.

Re: Radiator cap

Reply #10 – January 02, 2021, 11:53:23 am

Quote from: craneman – January 02, 2021, 11:33:44 am

I was only pointing out it is a truck, not auto cap. They won't be available at Autozone etc. Napa can get it.

Think I got our new U300 cap at O'Rielly's from their stock. Didn't have to order.

Pierce

Re: Radiator cap

Reply #11 – January 02, 2021, 12:04:08 pm

Seems like Foretravel did the expansion tanks like the air filter enclosures,every 99 320 may not have the same tank and /or cap,so makes sense to take the old one in,still trying to figure out Gleams post about the one he got from MOT,it would either be "leaking"
by defect or some other problem,when the cap releases the coolant is supposed to go to the plastic tank,does that happen?

Re: Radiator cap

Reply #12 – January 02, 2021, 12:20:53 pm

1) I don't have original cap....MOT took it
2) the cap they replaced it with leaked.I took a picture of the leak to send to Eric, service manager. My local mechanic took it, to help me get a new one. I now have NOTHING to bring to a supplier.
3) Local Auto Zone didn't have one
4) I had asked Keith why, when I removed the cap, antifreeze spilled out. My expansion tank was dry??!!!??? He did not know.
5) I blew out the hose from cap to expansion tank, " just in case"
6) I will measure the opening and, maybe, trace it to bring with me, Monday, on my quest to replace 5e cap
Whole lotta trouble for a simple item.....eh?

Re: Radiator cap

Reply #13 – January 02, 2021, 12:25:18 pm

Quote from: John44 – January 02, 2021, 12:04:08 pm

Seems like Foretravel did the expansion tanks like the air filter enclosures,every 99 320 may not have the same tank and /or cap,so makes sense to take the old one in,still trying to figure out Gleams post about the one he got from MOT,it would either be "leaking"
by defect or some other problem,when the cap releases the coolant is supposed to go to the plastic tank,does that happen?

John,

The fitting soldered into the neck at right at where the radiator cap fits leaked on ours and we lost coolant that should have been going to the plastic tank. That's when I went to the part store and got a new radiator cap. It didn't help but when I looked at the little fitting, I could see that it needed re-soldering. That fixed it.

Plus, Foretravel installed vertical side radiators that had radiator caps and then the next year, went to horizontal side radiators with no cap. The only cap is on our black metal coolant tank with the sight glass and low level sensor.

Pierce

Re: Radiator cap

Reply #14 – January 02, 2021, 01:05:41 pm

Glenn, read reply #6

Radiator Cap

Re: Radiator cap

Reply #15 – January 02, 2021, 07:23:10 pm

I, too, tried to upload picture this morning. Tried about six times. I don't have NAPA here, so hope I can find the right one on Monday.
Note the cap MOT installed. Mechanic said it was "junk"

Re: Radiator cap

Reply #16 – January 02, 2021, 07:34:24 pm

This shows on your photo where our tube came partially unsoldered and leaked.

Pierce

Re: Radiator cap

Reply #17 – January 02, 2021, 08:27:16 pm

Glenn,

I thought this was a good site on how to measure and select the proper radiator cap for your coach. It has a clickable link to the correct cap once you do the measurements.

https://knowledge.northernfactory.com/en/articles/24-how-to-choose-the-correct-radiator-cap

Pierce

Re: Radiator cap

Reply #18 – January 02, 2021, 08:44:12 pm

Here's another option found in a forum search.

https://www.oreillyauto.com/detail/b/stant-5674/cooling---heating-16773/radiator-coolant-recovery-cap-16928/radiator-coolant-recovery-cap-12848/aa30a11e4d6e/stant-15-psi-radiator-cap/10294/5699256

Re: Radiator cap

Reply #19 – January 02, 2021, 10:24:19 pm

Chuck,

While I don't see a part number on ours, it does say 15 psi so this may be the ticket. I threw out the box long ago.

Pierce

Re: Radiator cap

Reply #20 – January 03, 2021, 07:49:22 am

Quote from: Pierce & Gaylie Stewart – January 02, 2021, 11:53:23 am

Think I got our new U300 cap at O'Rielly's from their stock. Didn't have to order.

would you have the brand and part number would like to replace my cap I just did the radiator and it would be a good idea to install a new Cape

Re: Radiator cap

Reply #21 – January 03, 2021, 10:26:38 am

Rick,

I think Craneman dialed it in for mine as well as others with the same tank with the https://www.oreillyauto.com/detail/b/stant-5674/cooling---heating-16773/radiator-coolant-recovery-cap-16928/radiator-coolant-recovery-cap-12848/aa30a11e4d6e/stant-15-psi-radiator-cap/10294/5699256 cap. Looks like mine but like I said, it came with only the 15 psi rating on the top.

When you install the new cap, you can quickly tell if it's the correct model from the pressure needed to compress the spring and if it turns and locks. Plus, it's really inexpensive. Bet Eastern Texas would charge a lot more.

Pierce

Re: Radiator cap

Reply #22 – January 03, 2021, 12:16:43 pm

I needed a new radiator cap a couple of months ago my original was round.
I went to Napa and got one but it had six sides and seem to cut into the overflow hose every time you turned it.
I kept on looking and ended up with a Stant 10294 radiator cap Which is mostly round with four dog ears.
It's actually made in Mexico where you are located

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