Re: [alfa] Re: 115 spider cooling system saga bypass valves

["Dean W. Cains" <dwc@xxxxxx>]

Hi Group:

I've had a more than a few Spica cars in the last 25 years, and since 1 
year ago, my first L-Jet Spider.  All of their bypass hoses have had an 
appropriate bulge for the bypass restrictor.  I usually cut the old hose to 
extract the restrictor, then always use some lube, or another, to get the 
restrictor into the new hose.  I've used silicone spark plug boot grease, 
Crisco, and Vaseline on various past attempts.  Lately, I've taken to using 
K-Y jelly, as it's quite slippery, and water soluble, so the cleanup is easy.

Both my Spider's now have the restrictor, but I'm still not convinced of 
its value.  I've had cars with no restrictor, or the restrictor installed 
backwards, or installed properly, but I've never been able to tell the 
difference.  I think this is because a 105/115 cooling system in good, 
original condition has a large reserve capacity.  Details like the 
restrictor, or even a thermostat without the reverse poppet valve, can 
seemingly be omitted without much consequence.  Even so, once I learned 
which parts were correct, I've always made sure they were in place.  If the 
restrictors are scarce, the proper thermostats aren't, and a Stant 
equivalent can be had for ~$7 almost anywhere (at least for the pre-L-Jet 
Spider's).

I wonder if guys having cooling system troubles are using too high a ratio 
of anti-freeze to water, which is a mistake I've made.  25% Dex-Cool to 75% 
distilled water works best for me here in south Florida, and I can easily 
see an increase in the stabilized coolant temp with a 50/50 mixture, 
although still never above ~195F.  And, that's not to say 195F isn't a 
proper temp, as too cool is just as bad as too warm.  Hopefully none of us 
will try the ever-popular rice-boy trick of running with no thermostat, in 
the hopes of fooling the FI into providing a richer mixture.

Regards,

Dean
Lutz, FL
'74 & '87 Spider Veloce's

At 01:38 AM 11/15/2003, you wrote:

> Date: Fri, 14 Nov 2003 16:26:30 -0800
> From: Jon Pike <jhpike@domain.elided>
> Subject: [alfa] Re: 115 spider cooling system saga  bypass valves
>
> Hmmm...  I read the article,  and as it looks to me,  the flow
> restrictor still has some use.
>
> It isn't just a basic restrictor of a single hole.  It is an aprox 1/8"
> orifice, in a spring loaded plate of maybe 1/2" dia.  So, when the
> thermostat is fully closed,  the pressure overwhelms the spring pressure
> and you get a big bypass flow thru the engine as it warms.  Then,  when
> the thermo starts opening,  the pressure goes down,  the bypass valve
> closes,  leaving the smaller hole for less bypass flow,  eventually the
> thermo opens fully and at the same time blocks the bypass for full
> radiator flow.
>
> Possibly the limited bypass flow helps the thermostat block plate close
> off..
>
> Anyway,  this I figured out by looking at the old one I have laying
> around in a hose from my basket case motor.  So, I'm sold...  and want
> to put it in a new hose for my rebuilt motor.
>
> $100,000 question... how the heck do you get this thing into a new
> hose,  when it looks to be 20% larger in diameter than the hose?  Boil
> the hose and use a speculum??   Or can you still buy bypass hoses with
> them embedded inside?
>
> Jon
--
to be removed from alfa, see /bin/digest-subs.cgi
or email "unsubscribe alfa" to majordomo@domain.elided