Scorp. Fuel Pump

[davidb]

After FINALLY completing my 42 DCNF install I turned
on the electric 1/2 hour ago. New fuel pump, new hoses,
new filter. It goes: "RATEY-RAT-DAT". Sometimes the tone
of same changes. I suspect some of the hoses from the
gas tank I've either plugged or abandonded may require
some nature of normal atmospheric relief creating a
vacumn. Never intended to start the thing up today. A
mere whirring sound from the fuel pump would have sa-
tisfied me. Thanks all.

[DJ]

Sounds like you have one of those square block interrupter-type (http://www.pegasusautoracing.com/productdetails.asp?RecId=83) pumps. If that's the case, that's just the way they sound. More of a "clacking" or "tapping" sound. Never a "whirr". They work fine but the noise is annoying.

You may find that you also need an adjustable pressure regulator if you don't have one. Webers don't need (nor do they like) much pressure. I should still have a regulator somewhere in my stash that you can have if you need it.

[Paul Dempsey]

Hi, I hope you sort your pump out one way or another. I used to live in St Loius . N Grand Avenue. I loved it there and sometimes wished I'd never come back to England.
I have a S2 Montecarlo Spider, black.
I wondered what the flags mean next to the US flag by your name, cheers Paul.:)

[davidb]

That looks like my pump D.J., got it from Csaba. Same one Pierce
Manifold, others sell. I wondered about a FPR [fuel pressure regu-
lator] as TMH sells them yet Csaba said I didn't need one, hmmm ?
Either I have a bad pump or my connections are wrong [vacumn].
It's sound level is not merely annoying but alarming. A click, click,
click I can feature but not the RATTY-TAT-RATTY-TAT this one makes.
Country & state are the flags Paul.

[Paul Dempsey]

Ah , I never realised that the states Had their own flags, cheers Paul.:eek:

[Will]

Did you set up a return line, David? If not, that's likely your problem. IMO the correct way to set these up is tank, pump, carb, bypass regulator, return line back to the tank. even without the regulator, IMO you need a return line with a small restrictor so that the pump is not cycling against a completely closed hydraulic system (gasoline doesn't compress). This can result in excess noise, etc.

[davidb]

Thanks Will. My pet theory on this issue is hose mis-connects or
no connect @ all creating a vacumn: i.e the pump is trying but
saying I'm making this godawful noise because I don't work under
a vacumn you Moron. Yes I have tank to filter [you left out filter],
filter to pump, pump to carb. I've boobed up/left out a hose some-
where. I hope I figure it out before some well meaning soul asks
me if I have gas in the tank. I'm not the sharpest knife in the drawer
sometimes but please. Thanks. And yes Paul it's the United STATES
of America, a confederation if you will. Every individual state is
somewhat sovereign [sp?], independent of the dreaded "Feds". To
paraphrase Toqueville or Churchill it's a democratic mess that barely
works but if you want efficiency hire a dictator. Gez, sorry. I thought
this was Lancia tech forum.

[DJ]

Did you set up a return line, David? If not, that's likely your problem. IMO the correct way to set these up is tank, pump, carb, bypass regulator, return line back to the tank. even without the regulator, IMO you need a return line with a small restrictor so that the pump is not cycling against a completely closed hydraulic system (gasoline doesn't compress). This can result in excess noise, etc.

Will, most people with dual DCNFs don't bother with a return line as it's not needed. The DCNFs don't have a fitting for this anyway.

Besides, if everything is correct the pump should stop once it reaches full pressure.

[DJ]

Thanks Will. My pet theory on this issue is hose mis-connects or
no connect @ all creating a vacumn: i.e the pump is trying but
saying I'm making this godawful noise because I don't work under
a vacumn you Moron. Yes I have tank to filter [you left out filter],
filter to pump, pump to carb. I've boobed up/left out a hose some-
where. I hope I figure it out before some well meaning soul asks
me if I have gas in the tank.

First thing, David, it doesn't sound like you've left anything out but it should be:


Tank to pump
Pump to filter
Filter to carbs


That change in itself may fix it for you.

Also, I've accidentally crossed the tank connections in the past but I assume you've made sure that's correct.

Have you check the in-tank pickup to make sure it's not clogged? Those screens on the bottom get really crapped up over time.

Do you have fuel in the tank? :rolleyes: Sorry. Couldn't resist.

[davidb]

That was gonna be my next step D.J.: tank to pump as opposed
to tank to filter. I'm not the brightest lightbulb in the room but
it never makes sense to me to have the pump 1ST & the filter
2ND. YES I know the tank should be dousched. But w/o doing
that, the pump being 1ST, has to deal w/30 yr. old crud in the
fuel flying thru it. The car ran 20+ months ago before the re-
store began so I'm assuming the pick-up is okay. I'll try the
order switch 1ST & deal w/hoses next. Gives me something to
do this Holiday weekend. We've had wave after wave of thunder-
storms yesterday, today, more tomorrow. No bar-be-ques in St.
Louis this weekend. Thanks. Back later . . .

[Darren]

Hi David,

This is the sort of thing I'd do - but maybe worth checking - you have mounted the pump the right way round? Ie got your inputs and outputs the right way round?

Hope you get it sorted mate

Cheers

[davidb]

Okay, after yet another trip to NAPA for MORE fuel hose I did
the swap: tank to pump, pump to filter, filter to carbs. Still
did the RATTY-TAT-TAT then began to become more quiet,
shut it down. Energized it after a bit, all quiet. Maybe you
are correct D.J.: once pressurized it'll shut-up. Darren I had
the pump & hoses oriented from the get-go. Now that fitting
on the Alquati manifold? The big pipe goes to the brake bo-
oster for vacumn assist right? Where the hell does that smal-
ler pipe go? Back to the smaller fitting on the gas tank or to
the charcoal canister. If it's not one thing then it's another.

[DJ]

Okay, after yet another trip to NAPA for MORE fuel hose I did
the swap: tank to pump, pump to filter, filter to carbs. Still
did the RATTY-TAT-TAT then began to become more quiet,
shut it down. Energized it after a bit, all quiet. Maybe you
are correct D.J.: once pressurized it'll shut-up.

Cool. Glad that part worked out.


The big pipe goes to the brake booster for vacumn assist right?

Correct!


Where the hell does that smaller pipe go? Back to the smaller fitting on the gas tank or to the charcoal canister. If it's not one thing then it's another.

If you're talking about the small nipple on the bottom side of the manifold near #4 cylinder, that connects to the nipple on the top of your coolant tee on the front of the engine. Not something you want to connect to your fuel tank or charcoal canister. If that's not the connection you're talking about, I don't know what you mean.

[davidb]

D.J. thank you as always. I'd take a pic but it's totally buried
under the carbs. The Alquati manifold Andrew S. sold me
came w/this fitting. It screws into the manifold. The larger
pipe which comes straight out is approx. 1/2" which I ran
to the brake booster. The other smaller pipe outlet, on that
fitting, is like 1/4" O.D.. I do not know if that is superflous
or need be connected somewhere. The other fuel tank outlet,
the charcoal canister? Dunno. Basic thanks here again.

[DJ]

D.J. thank you as always. I'd take a pic but it's totally buried
under the carbs. The Alquati manifold Andrew S. sold me
came w/this fitting. It screws into the manifold. The larger
pipe which comes straight out is approx. 1/2" which I ran
to the brake booster. The other smaller pipe outlet, on that
fitting, is like 1/4" O.D.. I do not know if that is superflous
or need be connected somewhere.

Sorry. Got it now. I forgot about that mis-matched tee fitting. It comes from the original Scorpion manifold and I forget where it connects on the stock setup. I believe I just put a vac cap on it.


The other fuel tank outlet,
the charcoal canister? Dunno. Basic thanks here again.

That's the return line from the stock carb setup. I use it for my FI setup too but you can just cap it with the DCNFs.

The vents off the top of the tank should be tied together with a small "Y" pipe and be piped over to the bottom inlet of the charcoal canister.

[Darren]

Hi again David,

Glad you got it sorted! The small pipe T'ed off the brake booster pipe is for the little black vacuum collector on a Monte, which changes the direction of airflow in the heater matrix. I think the Scopion would be the same, unless you have aircon maybe?

If you don't have the black box, just plug it.

Cheers

[davidb]

That was the hose Darren, was right there, pushed right on.
Looking forward from the coolant tank comes the charcoal
canister right? Don't have anything to connect there now.
Then comes the shock tower top then some kind of elec.
gizmo w/a hose fitting on the back end. What's that? Still
don't know what to do pipe w/that 2ND smaller tank pipe
on the sender. I'm concerned about making a vacumn in
the tank now. This is becoming one puzzle solved, two
more created. AHHHHH !!!!

[DJ]

Hi again David,

Glad you got it sorted! The small pipe T'ed off the brake booster pipe is for the little black vacuum collector on a Monte, which changes the direction of airflow in the heater matrix. I think the Scopion would be the same, unless you have aircon maybe?

If you don't have the black box, just plug it.

Cheers

Thanks for the reality check, Darren. I thought there was something I was forgetting.

AC cars all use the vaccuum reservoir I thought the non-AC cars didn't have it.

[DJ]

Looking forward from the coolant tank comes the charcoal canister right?

Sounds like your talking about the little round vacuum reservoir there, David. One larger hose to the manifold, one very small vac hose that runs all the way up to the heater vac switch in the center console. I highly recommend replacing the small hose to the console. Mine was all chewed up by mice. :mad:

The charcoal canister is on the crossmember down near the bottom of the fuel tank on the driver side.


Then comes the shock tower top then some kind of elec.
gizmo w/a hose fitting on the back end. What's that?

A picture would help with this one David. It sounds like part of the emissions systems and can likely be eliminated.


Still don't know what to do pipe w/that 2ND smaller tank pipe
on the sender. I'm concerned about making a vacumn in
the tank now. This is becoming one puzzle solved, two
more created. AHHHHH !!!!

You must have missed that part of my previous post, David. You DON'T want to run a vac line to the tank. Here's the text of what I posted.


That's the return line from the stock carb setup. I use it for my FI setup too but you can just cap it with the DCNFs.

The vents off the top of the tank should be tied together with a small "Y" pipe and be piped over to the bottom inlet of the charcoal canister.

[davidb]

Looks like the PO took out the charcoal canister. I see where it
might have been,mounting point on the X-member, studs, no
canister. As my passenger side is still gutted I can follow the
vacumn hose all the way. It looks okay. I think I know how to
attatch that 2nd smaller sender pipe. Back to the cross-over
side-to-side hose on top of the gas tank w/a tee. I'm hoping
to get Dan C. over here w/i the next several weeks. He can
peruse the mess I've made. Thanks Gents.

[DJ]

Looks like the PO took out the charcoal canister. I see where it
might have been,mounting point on the X-member, studs, no
canister. As my passenger side is still gutted I can follow the
vacumn hose all the way. It looks okay. I think I know how to
attatch that 2nd smaller sender pipe. Back to the cross-over
side-to-side hose on top of the gas tank w/a tee. I'm hoping
to get Dan C. over here w/i the next several weeks. He can
peruse the mess I've made. Thanks Gents.

Am I not being clear enough or are you just not paying attention? :)

The extra connection on the fuel tank pickup/sender should just be capped. It is nothing more that the fuel return line from the stock carb. The DCNFs don't have (nor do they require) a return line.

The vent lines off the top of the tank should be connected to a charcoal canister. You can use a canister fro most anything. You DO want the canister because without it you'll get a LOT of fuel smell.

You can have my old canister if you want it. I have a new one that mounts differently. I don't have the metal bracket that mounts it to the crossmember but I'd imagine you could rustle one up.

[davidb]

I see no vent lines, this is nuts. Here's another question.
My fuel pump is hot straight from the battery. Likely the
POs re-wire. I've put in a Hella kill switch as an anti-theft
device which I used to test the pump. Surely one need have
the ignition key in some position before the pump gets elec.?
If I develop a gas leak I have to take out the kill switch key
to stop fuel flow? Makes ZERO sense to me. Jesus . . .

[DJ]

I see no vent lines, this is nuts.

Here's a couple old pictures I found for you. One shows they way I tied together the vents off the top of the tanks and hooked them to the bottom of the charcoal canister. The "Y" fitting was taken from somewhere else in the old emissions system.

The other pictures shows the charcoal canister in place. The line off the top should go into the intake system before the carb.


My fuel pump is hot straight from the battery. Likely the
POs re-wire. I've put in a Hella kill switch as an anti-theft
device which I used to test the pump. Surely one need have
the ignition key in some position before the pump gets elec.?
If I develop a gas leak I have to take out the kill switch key
to stop fuel flow? Makes ZERO sense to me. Jesus . . .

The pump should be wired to power via a relay that is energized only when the engine has oil pressure. You should have to crank the engine over a few seconds before the pump will energize. This is, IMHO, a very important safety feature and should be re-installed.

[Will]

Ha ha, I missed this thread, DAVID IS CORRECT I did "leave out" FILTER!

Ok, now I have a question (listening, DJ?) On the setups with dual carbs (which I have never done, one carb is enough PITA for me!) if you do NOT fit a return line, what happens when the fuel pump jacks up the pressure against closed seats? Do DUAL carbs not dribble, for some reason that I am not seeing? Is the carb seat/needle design iself different? I like to put things in neat boxes, and I don't understand why DUAL carbs don't leak and SINGLE carbs do if there's too much pressure.

It takes TWO SPST relays or a SPDT relay for the fuel pump because it needs power when CRANKING and no oil pressure, in addition to oil pressure and running. Otherwise, the thing will not prime. Better yet, install the Holley "oil pressure safety switch" which is designed for this purpose and has three terminals, it's a SPDT pressure switch. :)

[davidb]

I couldn't resist referencing your filter omission Will. I've put
every flavor of relay I have in the receptacle the PO jumped
[after removing it] & I'm still getting juice straight from the
battery. All the bottom feed wires in the relay block look "proper"
according to the schematic. I walked away from it for a few days
to clear the cache between my ears. Might try again this weekend.