Vacuum Gauge for fuel line

[monst]

Hello,
 Can anyone point in a direction...
regarding a vacuum gauge for the
fuel line... I would like to put one in...
It is a great idea.... Can someone
make a recomendation... on which one to get..
 thanks, Monst

[veeman]

I was actually hunting for the same thing recently:

http://www.vwdiesel.net/phpBB/viewtopic.php?t=5092

Anyway, I did some looking in McMaster's catalog a they have some gauges that would work...

Check out http://www.mcmaster.com/, page 547

3935K21 ABS-Case Vacuum Gauge 2% Mid-Scale Accuracy 1-1/2" Dial, 1/8" NPT Male Center Back Conn, -30" Hg
In stock at $8.71 Each

I haven't ordered one, but I think I'd need to also get a tee and some 1/4 barb fittings to put it in line with the fuel line.  I may try it soon.

[monst]

Thanks veeman
It is a great idea....
now what about the fittings...
like is brass ok?
I had heard some things that
copper is not good to have in
contact with Biodiesel.........
That is my direction I am headed....
once I feel she is worthy(josephine)......
if she wasn't NA.. I would try calling her josafiend.....
She has a header on her now.... I just choked her
out a little tooo much........ with the resonators....
trial and error...... and error and error......... :oops:

[fatmobile]

Get a vacuum gauge with  a big space      between 0 and 5 in.
 That is about the only area you will use and some of these gauges have very little needle movement between these 2 values.
 I suggest ebay.
 Also make sure it is lighted. Many of the vacuum gauges aren't meant to be dash mounted and you won't be able to see them at night.

[macsdub]

look on the dash of some big trucks with cats in them,,they had a vacuum guage for the fuelline setup like ya want

[veeman]

Get a vacuum gauge with a big space between 0 and 5 in.
That is about the only area you will use and some of these gauges have very little needle movement between these 2 values.

Understood... makes sense.

Also make sure it is lighted. Many of the vacuum gauges aren't meant to be dash mounted and you won't be able to see them at night.

My original idea was to leave it in place in the engine bay (I've already got three gauges in my console) much like EFI guys do with a fuel pressure gauge, but now that I think about it, would the gauge register vacuum if the filter was clogged and it was at idle or rev'd out of gear?  Not sure the reading will show unless there's a load on the engine. Is that correct?

[monst]

All great info here......
Yeah, good point V about....
whether it will show resriction at idle....
I have to think of this vacuum gig on
the fuel as sucking on a straw........
Oil fired oil burners do the same trip...
You stick a tank outside in the ground
and you must run 2 lines..... This vac
gauge would even be a good idea
here.... after filter before pump......
Sorry about that..... Can drive my
burner down the street......
Can you think of any brands of
guages that do the big space between 0 and 5 inches hg :?:

[fatmobile]

Yeah, these vaccum gauges can be found on the dash of old school busses too.
 With the vacuum brakes.... sometimes those are too big for a VW dash.
 Nice to have it on the dash but the gasser CIS VWs have a vacuum switch on the line going to the distriibutor, that is adjustable and could be used with a light on the dash or a beeper.