Losing coolant

[Don Bradner]

The parts book that came with this coach calls for a 7 lb. I have no idea when
this one was changed to a 13 lb.

There is a thread back in March of 2007 starting with post 20947 where Curt
Sprenger said:

"Coolant Pressure Control Cap...the 92 series manual recommends all
series 92 on-highway vehicle engines use a minimum 9 psi control cap.
My radiator cap is a 7 psi. Is this a Bluebird change? What are others
using? Should I be concerned? The engine temperature runs at about 185
to 195."

That thread ended up being more about alarmstats, misters, etc. but besides you
(Leroy) mentioning that you had a 13, Pete posted in that thread that the shop
that did his radiator replaced with a 15.

I'm going to guess that a higher one gets used precisely because the 7 lb, as it
loses strength, tends to let more slop out.

If you think about it, a 7 lb with a boiling point somewhere above 230 degrees
is into temperatures where the engine would be in real trouble anyway.
Increasing the cap pressure to 13 takes boiling to 250, but does that really
matter?

I'm thinking I will go looking for a new cap tomorrow as an easy "maybe fix",
and I will look for one around the same 13 lbs.

On 10/23/2008 at 6:17 PM Leroy Eckert wrote:

>I have a 13lb cap also and it is old. Same year.
>Leroy Eckert
>1990 WB-40 Smoke N Mirrors
>Dahlonega, GA
>Royale Conversion
>
>--- On Thu, 10/23/08, Joyce and Richard Hayden wrote:
>From: Joyce and Richard Hayden
>Subject: Re: [WanderlodgeForum] Losing coolant
>To: WanderlodgeForum@yahoogroups.com
>Date: Thursday, October 23, 2008, 8:32 PM
>
>Don, I would wonder why someone has put a 13 # cap on your cooling
>system. The standard for these engines have been 7#. I haven't heard
>of very many with anything above that.
>
>Dick Hayden - '87 PT 38 - Lake Stevens, WA - still in Medford, OR but on
>the road again tomorrow after the tranny is fixed.