Fuel Pump Prime?

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Topic author
MReno
Posts: 158
Joined: Sun Mar 03, 2019 6:39 pm

Fuel Pump Prime?

Post by MReno »

All,
I have a question regarding my '89 Waggy (AMC 360). This past weekend, I was able to fire it up in my barn. It typically takes a bit of starting fluid at first to turn over, but the will turn over on its own for the next few days. Please understand, this vehicle in new to me, bought last December for $800 as a project vehicle (to be a weekend "fun to drive" kick-around vehicle). It needs some work....but it would run when started (until now).

It is likely that the vehicle is out of fuel, or ran out of fuel while attempting to turn it over this past weekend, but I also had to disconnect the spark plug wires on the passenger side of the block to lift them off the cylinder head, so I thought that this could also be the issue...

The scenario was I was able to get the engine to turn over and idle for a pit (FYI- fuel gauge on empty), but then after a minute of so it dies. It would crank but no longer turn over, even when adding a bit of starting fluid to the carb. I then thought could the issue be that I disconnected the spark plug wires and maybe they were not put back on tightly. I checked them and they seem tight. Tried again, cranks hard, but would not turn over ( almost like carb is not getting fuel). There is an aftermarket clear glass fuel filter leading to the carb, and there is fuel in it, so I assume that would be sufficient to get the engine tor turn over. Tried again, no go, so I added about 1.5 gallons of fuel to the tank. Tried it again, cranks hard, but would not fire up.

My question is could the fuel pump have lost a prime, even though I see fuel in the filter, but the fuel is not being pumped to the carb? If this is not the case, I will check that each spark plug is firing (confirming distributor is properly functioning)?

Any other suggestions?
1989 Jeep Grand Wagoneer
Newbee to owing an old classic that needs some work, but she runs!

GrandW
Posts: 224
Joined: Mon Aug 20, 2018 6:19 pm

Re: Fuel Pump Prime?

Post by GrandW »

To check if fuel is getting to the engine, disconnect your fuel line, then turn the ignition on. If it's pumping, fuel should come out. Good luck.

Sent from my SAMSUNG-SM-G920A using Tapatalk
1987 Jeep Grand Wagoneer

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Fuel Pump Prime?

Post by candymancan »

Fuel pump is mechanical so there is no priming like an electric fuel pump.. itll pump only when you crank the engine.. Pumping the gas pedsl is what (primes) the carb by forcing gasoline into the carb.


Id replace all the wires ditributor rotor and plugs regardless. They are cheap enough. Get some chsmpion copper plugs. Some 7mm wires. And a brass distributor and rotor.

Id also do what he said... diconnect the fuel line at the carb and see if its squirting gasoline out.

You are pumping the gas pedal before cranking right ? 8f so how many times are you pumping it ? Have you tried pump the pedal many times then smelling the carb to see if fuel is getting to the carb that way ?
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
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tgreese
Posts: 7118
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Location: Medford MA USA

Re: Fuel Pump Prime?

Post by tgreese »

Typically if the engine requires a lot of cranking to start, it's because the fuel bowl in the carburetor has dried out. The float bowl will dry very fast if you leave the air cleaner off, or if there is a problem with the carburetor (leaky power valve or accelerator pump). Any new-old car with a carburetor typically needs a carburetor rebuild. These carburetors are notorious for "dry bowl syndrome" - going dry after sitting a short time, and needing lots of cranking, or better, a little gas or a shot of starter fluid in the carburetor. Does not take much running to refill the float bowl.

The TSM has a spec for fuel delivery using a pressure/vacuum gauge. These are cheap at Amazon - pick one. The carburetor needs very little pressure to function - you can run the engine from a gas can on the cowl feeding only by siphon to the carburetor. I expect the 3-nipple fuel filter will drain your fuel can rather quickly via the fuel return line, if you connect your siphon to the inlet side.
Tim Reese
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Topic author
MReno
Posts: 158
Joined: Sun Mar 03, 2019 6:39 pm

Re: Fuel Pump Prime?

Post by MReno »

So minutes before this issue came about, I could crank the engine right over. And before that, it would use squirt of starting fluid, and after two attempts would fire right up.

It was after I pulled the plug wires off the plugs on the passenger side and reinstalled to route the wires so they were not laying on the valve cover that the issue came about. I also had to disconnect and reinstall the two wires that connect to the top of the Accel Super Coil so they were better routed.

It was after all that when I ran into the issue with not getting it to start.

I added 5 gallons of fresh fuel and have tried pumping the accelerator a few times before attempting to start (and smelling fuel at Carb), but no go. I just bought new plugs and plan to replace them and reconnect the plug wires properly and see if that works. I have disconnected the fuel line from the carb and do have fuel to the carb, so I am wondering if it is an electrical issue, which does not seem possible since the starter engages, but the engine will not turn over.
1989 Jeep Grand Wagoneer
Newbee to owing an old classic that needs some work, but she runs!

will e
Posts: 5097
Joined: Sat Aug 18, 2012 8:21 am

Re: Fuel Pump Prime?

Post by will e »

okay, so if you squirt starting fluid or put a little bit of fuel down the carb it won't run for even a couple of seconds?
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Fuel Pump Prime?

Post by candymancan »

You sure you routed the wires right ?
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

SJTD
Posts: 1924
Joined: Tue May 21, 2013 12:02 pm
Location: Lompoc, Sunland or somewhere between

Re: Fuel Pump Prime?

Post by SJTD »

Lemme see. Engine ran. You messed with half the plug wires and the coil wires and the engine no longer runs?

I also suspect a wiring problem. Assuming it was reconnected correctly one might have an internal break.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Fuel Pump Prime?

Post by candymancan »

That or a bad coil.

Check the wire routing.. replace the wires like i said and thrn replace the coil. Its not that expensive for wires and a coil
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Topic author
MReno
Posts: 158
Joined: Sun Mar 03, 2019 6:39 pm

Re: Fuel Pump Prime?

Post by MReno »

Sorry guys,

Still not start after checking plug wires and having now installed new plugs. I tried switching the + & - on the Super Coil to see if maybe I connected them back opposite. That still did not produce a start. I again sprayed some starting fluid into the carb (non choke side), choked engine, and attempted to start. Engine still would not turn over. I confirmed fuel is being delivered to carb (by disconnecting hose at Carb and seeing fuel pump out). I guess my next step is to test my coil before throwing money at a new one. If still no turnover, then consider replacing coil, plug wires, and distributor.

Is there a way to fill carb fuel bowl, prior to me trying to start it again?
1989 Jeep Grand Wagoneer
Newbee to owing an old classic that needs some work, but she runs!

weeegoneeer
Posts: 230
Joined: Wed Apr 26, 2017 10:34 am

Re: Fuel Pump Prime?

Post by weeegoneeer »

I use a funnel with a narrow tip and a spraycan cap full of gasoline - you can pour some into the vent tube (at least on my holley).
1984 GW

letank
Posts: 4010
Joined: Wed Oct 03, 2012 9:16 pm
Location: SF bay area

Re: Fuel Pump Prime?

Post by letank »

for the 2150, if needed, I dump a good swig of gas , best guess an ounce or 2, down the throttle bore, choke kept open with a large screwdriver.

on some 2150 depending on the gasket, the bowl vent on the driver side is the good vent to dump gas using the small funnel method
Michel
74 wag (349 Kmiles... parked, next step is a rust free body)
85 Gwag (229 Kmiles... the running test lab)

PossumJr
Posts: 103
Joined: Fri May 10, 2019 8:04 am
Location: Eastern NC

Re: Fuel Pump Prime?

Post by PossumJr »

MReno wrote:Sorry guys,

Still not start after checking plug wires and having now installed new plugs. I tried switching the + & - on the Super Coil to see if maybe I connected them back opposite. That still did not produce a start. I again sprayed some starting fluid into the carb (non choke side), choked engine, and attempted to start. Engine still would not turn over. I confirmed fuel is being delivered to carb (by disconnecting hose at Carb and seeing fuel pump out). I guess my next step is to test my coil before throwing money at a new one. If still no turnover, then consider replacing coil, plug wires, and distributor.

Is there a way to fill carb fuel bowl, prior to me trying to start it again?
Assuming your engine still has the Motorcraft 2bbl on it, there will be two bowl vents sticking up right inside of where the air cleaner sits on top, closest to the front of the carb, you can put gas straight into the bowl that way.

Have you positively checked to confirm spark other than trying to crank the engine? There's a few ways to do it and will at least rule that out if you do.
1979 J10, 360/QT

Topic author
MReno
Posts: 158
Joined: Sun Mar 03, 2019 6:39 pm

Re: Fuel Pump Prime?

Post by MReno »

Thanks for the reply. I got it running. So my '89 has a 4bbl Edlebrock on it, which I rebuilt anyways, however I believe it was my ignition control module that failed. I had it tested and test indicated it was bad. Once replaced and after a bit of starting fluid, she turned right over! Like a dummy, I also saw a negative wire from the coil that had come disconnected from the negative battery terminal, so this could have also been part of the issue.

Either way, she runs strong now, just need to properly tune the carb!

Thanks for your reply.
1989 Jeep Grand Wagoneer
Newbee to owing an old classic that needs some work, but she runs!
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