High idle on 340

Storming Brains are good.

You are probably right about it being a heat insulant (as well) but Volvo
told me it was there because of the bowing carb base issues. I do not
actually remember there being a paper thin gasket on each side of the thick
thingy, there may have been it is just that I can not remember.

I do remember putting a straight edge across the carb base and noticing it
bow upwards in the centre. The carb base has 4 fixing bolts (studs/nuts)
one on each corner and either the base of the carb needed to be thicker ot
it needed another 2 fixing studs in the middle to help stop the bowing.. It
seems that the more the 4 corner bolts are tightened the greater the chance
of the carb base bowing.

I like the idea of making and trying a thicker paper/thin card gasket and
fit this between the thick spacer and the carb base, it could just work.
WHAT DO YOU HAVE TO LOOSE.

I spoke at length with people about using some form of liquid gasket
including a techi who builds F1 racing engines and to a core they were NOT
in favour for bits being effected by the petrol vapour and getting stuck
somewhere inside the carb/jet etc.

We also discussed having the carb base skimmed but keeping swarf out of the
carb was close to an impossibility so would have needed a complete carm
strip and clean, and for what, at best a temporily flat but even weaker carb
base.

Andy



"Randy G." <(E-Mail Removed)> wrote in message
news(E-Mail Removed)...
> "Tim \(remove obvious\)" <(E-Mail Removed)> wrote:
>
>>> This is a very common issue with the Solex and Weber carbs, cost cutting
>>> by Renault is my guess. At the base of the carb is a 1/2 inch thick (or
>>> thereabouts) gasket that was supposedly designed to get around the carb
>>> base bowing, it was never particularly successful. This gasket costs
>>> something stupid like £80 and must be replaced each time the carb is
>>> removed.
>>>
>
> mind you, I have not worked on these specific carbs but do have some
> Solex experience.
>
> Is it actually a gasket, or is it a hard, lastic spacer. usually the
> "thick" gaskets are a heat speacer made to insulate the carbh from teh
> heat of the intake manifold when the car is turned off after a hot
> drive. If that is the case, I would find some gasket material to make
> gaskets for both sides.
>
> Another alternative- thoroughly clean the carb base and manifold. Wrap
> the bottom of the carb in some stretchy plastic or shrink wrap and do
> the same on the intake manifold. Use some JB Weld, put a thin coat on
> the gasket and assemble with the least amount of torque possible. Wait
> until it hardens, then disassemble, remove the plastic wrap, and
> reassemble.
>
> Are there no gas-resistant sealnts? I seem to rmember some epoxy made
> to seal gas tanks and such, or even use something like Kreem or other
> tank liner material to build up a gasket to form fit the warpage.
>
> Just brainstorming... maybe more the later than the former....
>
>
> __ __
> Randy & \ \/ /alerie's
> \__/olvos
> '90 245 Estate - '93 965 Estate
> "Shelby" & "Kate"

"Andy Coles" <(E-Mail Removed)> wrote:

>Storming Brains are good.
>
>I spoke at length with people about using some form of liquid gasket
>including a techi who builds F1 racing engines and to a core they were NOT
>in favour for bits being effected by the petrol vapour and getting stuck
>somewhere inside the carb/jet etc.
>
How about this: make a thin metal gasket to match the outside
perimeter of the carb. Run a thin bead of JB Weld along the base of
the carb- mostly near the center where it is bowed up, then place the
carb on the gasket on a sheet of glass so that the JB Weld fills the
gap between the metal gasket and the base of the carb. In essence, you
are making a new carb base a few tenths thick, but not making the carb
any taller than it has to be.

>We also discussed having the carb base skimmed but keeping swarf out of the
>carb was close to an impossibility so would have needed a complete carm
>strip and clean, and for what, at best a temporily flat but even weaker carb
>base.
>
I agree.



__ __
Randy & \ \/ /alerie's
\__/olvos
'90 245 Estate - '93 965 Estate
"Shelby" & "Kate"