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Unable to start Bronco

Bill R

Newbie
Joined
Oct 5, 2017
Messages
41
I have not started my '76 Bronco in about a year and it did not start yesterday when I gave it about four good tries. I stopped at that point to ask if anyone has any suggestions (for someone that is not a mechanic). The fuel gauge was on empty and I put in about 3 gallons of fresh high octane gas and I have a good strong battery. It has been hard to start in the past and I think it may be the carburetor (or maybe the operator).

  • Are there any procedures that are helpful after the engine has not been started for a long time?
  • Should the gas pedal be used when starting?
  • Is using Starting Fluid in the carburetor a good idea?
Any suggestions will be appreciated. Thanks, Bill R
 
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BUCKWILD

Full Member
Joined
Jun 20, 2016
Messages
350
Loc.
Butte county
Dose the engine turn over? if so yes you need to pump the pedal a few times but it will take some tine to pump gas to the carborator. starting fluid is ok,brake clean works too.
 

NicksTrix

Bronco Guru
Joined
Aug 1, 2001
Messages
6,386
take some of your fuel and fill the fuel bowl through the vent. work the throttle and see it squirt into the intake. you now have fuel in the system. slight splash out of your bottle won't hurt you. don't overdue it. add some spark and it should light off.

don't be surprised if your fuel pump is toast. the fuel these days kills rubber based parts like pump diaphragms, accelerator pumps in the carb..
if you know you are going to park it for long periods of time, use your fuel selector and cut it off, let it run out of fuel...
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
I have not cranked my '76 Bronco in about a year and it did not crank yesterday when I gave it about four good tries. I stopped at that point to ask if anyone has any suggestions (for someone that is not a mechanic). The fuel gauge was on empty and I put in about 3 gallons of fresh high octane gas and I have a good strong battery. It has been hard to crank in the past and I think it may be the carburetor (or maybe the operator).

  • Are there any procedures that are helpful after the engine has not been cranked for a long time?
  • Should the gas pedal be used when cranking?
  • Is using Starting Fluid in the carburetor a good idea?
Any suggestions will be appreciated. Thanks, Bill R

Yes give up n sell it to me;D
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
Seriously. ..pump the pedal as the motor is spinning over. Like said could be several things but if it was empty it could take awhile to prime up. You have two tanks or one? I didn't notice if you said .

I don't recommend using starting fluid.
 
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Bill R

Newbie
Joined
Oct 5, 2017
Messages
41
Thanks for the replies. The battery and starter are doing a good job and the engine is turning over strongly but it is not firing. I only have one gas tank. Bill R

From NicksTrix: "if you know you are going to park it for long periods of time, use your fuel selector and cut it off, let it run out of fuel."

What/where is the fuel selector?
 

Slowleak

Bronco Guru
Joined
Sep 12, 2013
Messages
3,732
Loc.
Georgia
Unable to crank Bronco

What have you done so far besides cranking and pumping the pedal? Like Nick said, fill the carb bowl, check for fuel squirting in the carb, or dump a little gas into the carb and crank it..... then let us know what happens.
 

half cab

Contributor
Guru Bronco
Joined
Dec 8, 2010
Messages
16,306
Thanks for the replies. The battery and starter are doing a good job and the engine is turning over strongly but it is not firing. I only have one gas tank. Bill R

From NicksTrix: "if you know you are going to park it for long periods of time, use your fuel selector and cut it off, let it run out of fuel."

What/where is the fuel selector?

You wont have one if only one tank. Can you remove the breather and see if gas is squirting when you work the throttle? Can you confirm if it firing or not?
 
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Bill R

Newbie
Joined
Oct 5, 2017
Messages
41
When I said it is not firing, I should have said as I was trying to crank it there was no sound of the engine beginning to run. I will check for the gas squirting in the carburetor tomorrow. I will also try pouring some gas in the carburetor.
Thanks to all who replied, Bill R
 
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BajaBronco

Contributor
Bronco Guru
Joined
Apr 30, 2003
Messages
3,931
Bill, I 2nd the motion to check for fuel squirt from carb... I always check this almost first thing on any Bronco I'm trying to start that has sat for any length of time. Even a small amount of moisture in the carb will gather at the bottom of the jet pathway and keep it from squirting at the venturis. Good luck and report back to us.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,346
What they said. It could be as simple as a weak pump (from sitting) is just having a harder than normal time priming itself from the tank.
Usually when a pump gets weak it will struggle to initially prime, whereas it can pull pretty hard when the engine is already running. To that end I've succeeded in getting a few weak pumps to start sucking by putting some gas directly into the float bowls so that the engine can run on it's own for at least several seconds to get fuel back into the lines.
Just putting some gas down the through is not always enough. It might start that way, but runs out of gas too quickly.

Even new pumps (well, ESPECIALLY new pumps!) will have this problem if they sit too long.

Good luck.

Paul
 
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Bill R

Newbie
Joined
Oct 5, 2017
Messages
41
I removed the air cleaner this morning and saw the bowl with flapper and two openings (not sure of correct terminology). I worked the throttle linkage next to the carburetor and could not see any gas being squirted. I then had someone pump the accelerator pedal and still did not see gas being squirted.

I poured a small amount of gas into the bowl and the engine sounded like it was cranking for just an instant and then went to the sound of the battery turning the starter. I did that several times with the same result. I didn't know how much gas I could safely pour in the bowl so I just poured a small amount.

I appreciate the help of everyone. I am no mechanic but I do have time, basic tools and walking around sense so maybe we can make some progress together. Thanks, Bill R
 

Slowleak

Bronco Guru
Joined
Sep 12, 2013
Messages
3,732
Loc.
Georgia
Could be the fuel pump or it could be a carburetor issue. I pour about an ounce down in the carb. Just don’t stand over it when it’s cranking....never should.

There should be a rubber hose in the fuel line just before it connects to the carb. One thing you can do is disconnect the carburetor side of the hose and, using something to catch the fuel, have someone crank the engine while you verify fuel is coming out of the hose. If it is, then you know the fuel pump is working and should be filling the carburetor bowl.

Next step is to take the top off the carb to see if the bowl is full, check for a stuck float, clogged jets etc.
 

NicksTrix

Bronco Guru
Joined
Aug 1, 2001
Messages
6,386
you can prob put a 1/4 cup into the bowl through the vent. fill till you can't put any more into it. it won't hurt it. needs to get through the accelerator pump to squirt.
id fill the bowl, put a splash in it and start it. if pump is still good it should refill itself as it continues to run. if it runs out of the fuel in the bowl then the pump is bad.

a pump is only about 15 bucks so you might just want to pick one up to have on hand. you can always take it back f you don't need it.
 
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Bill R

Newbie
Joined
Oct 5, 2017
Messages
41
Pardon me for being so slow to understand but I want to make sure we are talking about the same thing. When I removed the air cleaner and saw the flapper(?) and two ports(?) or openings, is that the bowl? Is that where I should have been able to see the gas squirting when the gas pedal was pumped? Is that also where I should have poured the gas?

Thanks to all for your help and patience, Bill R
 

Slowleak

Bronco Guru
Joined
Sep 12, 2013
Messages
3,732
Loc.
Georgia
Unable to crank Bronco

The flapper on the top is the choke plate. If you hold it open and look down into the carb, you should see fuel squirting when pumping the gas pedal or moving the throttle lever. That’s also where you pour the gas.

The fuel bowl is inside the carb on the front. It has vents on the top. You may or may not have the valved bowl vent.
672b53abe2623fd3ce389dc03deb4383.jpg

http://grantorinosport.org/bubbaf250/carb/carb02.html
 
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