13 psi Radiator Cap Question

[ToddIL9]

First post here! Been a long time lurker thinking about building an Astro camper conversion. Finally pulled the trigger on a 1999 in pretty good shape except for a leaky intake manifold. Got that job done along with a new water pump, hoses, and whatever little things I could think of replacing while I was in there.

I ended up replacing the radiator cap with a 16 psi cap but after reading a bit here I decided to go down to a 13 psi instead just to keep the pressure down a bit. Only problem is if you search for a 13 psi cap for a Chevy Astro you're not going to find one at a parts store.

I ended up buying a Stant 10329

https://www.amazon.com/Stant-10329-Lev-R-Vent-Radiator-Cap/dp/B000B8N3IM

Seems to fit just fine but I haven't tried using it yet. I'm curious if this is the same cap others on here are using.

Thanks for any help!

[CopperFiremist]

15982188

[ToddIL9]

15982188

Looks like that's the OEM GM 15 psi cap. I'm looking for 13 psi.

[CopperFiremist]

Correct. Replace lower intake manifold gaskets.

[ToddIL9]

Correct. Replace lower intake manifold gaskets.

What? Ok, I'm confused now. The lower intake manifold gaskets are brand new. I was running a 16 psi stant cap (everything is working fine btw). Just thinking about switching to a 13 psi cap to lower overall pressure. From what I've read on here a lot of people have done the same thing.

I'm not switching to stop a leak if that's your point.

[CopperFiremist]

My bad. Just run the OEM cap.

"Finally pulled the trigger on a 1999 in pretty good shape except for a leaky intake manifold.

[ToddIL9]

My bad. Just run the OEM cap.

Again, is there anyone here running a 13 psi cap that can tell me the stant part number they used?

[CopperFiremist]

Keep it OEM 15982188 Stant caps are junk anyways. They leak!

[ToddIL9]

My bad. Just run the OEM cap.

"Finally pulled the trigger on a 1999 in pretty good shape except for a leaky intake manifold.

Ummm, you left the next line of my quote out. Here's what I said:

Finally pulled the trigger on a 1999 in pretty good shape except for a leaky intake manifold. Got that job done along with a new water pump, hoses, and whatever little things I could think of replacing while I was in there.

Crap. Are you the welcoming committee here? Friendly place.

[WoodButcher]

LOL, "welcoming committee"
Copper is probably browsing the web on his phone. For warm fuzzies post a thread in the introduction section or put female for gender,,,
No, don't do that, we had that dance a few months ago
voltsmith was confused.

Welcome.
Most folk here would say run stock w/ a 195 thermostat as it just dumps in the expansion tank and returns when it cools. I can't see 2 or 3 lbs. making a difference when it comes to leaks but with a lower temp as a result of reduced pressure the heat / defrost would not work as well.
What made you think of the lower pressure cap? I haven't heard of that here.

[Mmusicman]

Not sure what the BIG deal is here?

Higher pressure cap is better for reducing boiling and overheating. If you feel it might cause leaks on an older engine.. then reduce pressure. No big deal. 13psi will still give more than adequate results. I run 16.

Oh, I also run Stant caps and have never had an issue. My system and recovery work fine.

Oh... and welcome to the group.

[RECox286]

1) 13 psi won't make a crooked rat's tail's difference to the cooing system.

2) I have done it when my truck's original radiator turned old enough to vote.

3) WELCOME to our insanity C'mon in, the water aint all that cold !

Uncle Bob