Funny you should mention it. As of TODAY, I think I have finally, for
the first time in 4.5 years, eliminated the vaporlock problem(s) in
mine! I've been really digging into it as: 1) it's annoying as @#!@$!,
and 2) replies to my posts about a month ago suggested roadsters
shouldn't have ANY vaporlock problems -- on a stock setup!
Tue, 28 May 2002 15:37 Napolean Dynamite wrote:
>get a vented gas cap
> (Aren't all gas caps vented, how would I know if mine is or isn't)
It should have an extra hole on top near the key lock on the cap. I was
told that if your tank goes PPFFFFFTT when you remove the cap, it's not
venting properly.
>use a less volatile gasoline
> (This one is out of my control I believe, but is there an additive
>that will make the gas less volatile)
I don't know about an additive, but I did read that volatility IS an
issue, refiners vary it between summer and winter, AND it varies between
states!! Nor do they have to report WHAT volatility you're pumping! From
what I read, volatility and altitude are big contributors problems to
vaporlocking.
>use newer hoses that have fewer nucleation sites where vapor bubbles can
>form
? if you say so :) . I'm not having any trouble with Pep Boyz fuel
lines, however if yours are old, I'd replace 'em all just to be sure.
>insulate the fuel lines
> (What is a good insulation and which sections should be insulated)
From the fuel pump to the carb -- especially as it passes over the
exhaust manifold. HOWEVER, I thought that *must* be a big issue,
but I pulled my vent/return fuel line (from the firewall) while
running (hot), and the gas coming out was COOL to the touch! So I
suspect additional insulation on the fuel line wouldn't be solving
the problem.
>re-route the fuel lines
Another 2L WyCROCer tried routing in front of the radiator, and had NO
noticeable improvement. Seems like somebody else on this list said it
DID help. So, YMMV!
>be sure the heat shield is in place
> (What does the heat shield look like and where is it located)
Looks like a piece of cheap 3"x14" (or so) sheet metal hanging off the
intake manifold under the carbs. It provides a shield between carbs and
exh manifold. The throttle return springs attach to it. If you don't
have it, your throttle springs are rigged. Extremely high odds your
throttle bushings are going to die a premature death rigged like that
(ask me how I know).
>check the vapor return valve on the carb inlet
? I assume you mean the vent/return valve in the fuel line from the
back carb to the firewall (returning to the gas tank)? (I think of that
more as an 'outlet' :) ).
> (Is this standard equipment on a 2000)
Yes. And do check it. When I was fighting my vaporlock, all I had to
do was pinch that return fuel line (when the car was hot and grouchy) and
it would start idling rough(er). The vent/valve is *really* simple; I
took it apart and cleaned it no problem. However if you don't have the
extra support bracket (I've only seen it on about 1/2 the cars I've looked
at), be careful handling it; the aluminum warps easily and it's a PITA to
get sealed again!
>install an electric fan
> (Who makes a good electric fan and where can it be installed on a
>Roadster)
I wouldn't -- solve the problem, don't circumvent. YMMV. I've seen them
installed in front of the radiator.
>install an electric fuel pump
> (Who makes a good electric fuel pump, and where should it be
>installed on a Roadster.
I wouldn't -- solve the problem, don't circumvent. YMMV. I've seen
several roadsters w/ pep boyz generic pumps mounted on the fender by
the battery.
>Also, what is the importance of an oil pressure safety switch if
>installing an electric fuel pump.)
I give up. What?
Anyway, I DID want to report that I seemed to have finally resolved
my vaporlock problem(s)! It appears that my (1.5 yr old Ztherapy!)
carbs had a number of problems with them, AND my vac advance wasn't
working (and losing vacuum out of the carb).
So I would have to agree with what everyone else told me - you
shouldn't have vaporlock problems on a stock set up, even at 7000'
altitude!
Dan Neff '69 2000
Colorado Springs, CO
http://www.wycroc.org
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