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Mechanic bubbys - F250 460 gas won't start


max power

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Ran great last night. 

Cranks and tries to fire every few revolutions but doesn't quite start. 

Tried ether (starting fluid) still wouldn't start leading me to think it is a spark issue  

Cleaned the contacts on the distributor and charged the battery. Had to leave for gut stuffing. Tried to change the fairly new fuel filter but couldn't figure out how to get the fuel lines loose. 

No pressure from shrader valve on fuel rail. 

All loaded up for the camper and dead in the water. 

Help a bubby out. 

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2 minutes ago, max power said:

Yes. It is spinning. It tried to fire every few revolutions. 

I think what he means is if you have a distributor (not coil packs) have you removed the distributor cap and have someone crank it over while you watch for your rotor button to spin.

What year and how many miles on this anyway?

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Yes. 

 

So went to my brothers for Thanksgiving and came home and tried it again. It cranked a few times and tried to fire. Crank fire crank Fire crank fire and eventually fired more often and finally started. So it's running now but I'm not sure how much I trust it.

Anybody ever have this experience or have any idea what to check? Both tanks work.

Edited by max power
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I'd stick a timing light on it, fire it up and watch the timing mark on the crank.  If it's dancing around erratically (more than 1 or 2 degrees) you're probably looking at doing a timing chain & gear set.

Just thought.  How's the fuel rail now?  Any difference in pressure?

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1 hour ago, Wandering Soul said:

I'd stick a timing light on it, fire it up and watch the timing mark on the crank.  If it's dancing around erratically (more than 1 or 2 degrees) you're probably looking at doing a timing chain & gear set.

Just thought.  How's the fuel rail now?  Any difference in pressure?

My timing light broke a while back and I haven't replaced it. Didn't check the fuel rail pressure. I'm on my way to the camper.

46 minutes ago, motocat12 said:

Were you giving it pedal when trying to start it. maybe flooded and why ether didn't catch?

Fuel injected

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After the pump primes you should be able to push down of the Schrader valve and it should shoot gas out if it has correct pressure. quick Google search says you should have 40-50 psi, and 20-30 running. If you prime the pump several times does it sputter longer?

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14 hours ago, JustinNck1 said:

After the pump primes you should be able to push down of the Schrader valve and it should shoot gas out if it has correct pressure. quick Google search says you should have 40-50 psi, and 20-30 running. If you prime the pump several times does it sputter longer?

 I read that too. Primed it and pushed down on the shrader and a little bit came out but it didn't shoot out. 

It ran good coming down here but kinda felt like the spark was weak, if that makes sense. Gonna get a cap and rotor and check the timing when I get home. 

 

Got it rawlins with me so if it won't start, we'll get a trailer and drag it home. 

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If I'm remembering correctly on that motor the fuel pressure regulator is on the fuel rail.  Both pumps can be working fine but the regulator can still bypass too much back to the tanks.  My dad had that model truck years ago and seem to remember he had an issue that the valve that switched between the two tanks on his got funky towards the end.  Sometimes had to switch back and forth a few times to get the rear tank to work.

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23 minutes ago, vf1000ride said:

If I'm remembering correctly on that motor the fuel pressure regulator is on the fuel rail.  Both pumps can be working fine but the regulator can still bypass too much back to the tanks.  My dad had that model truck years ago and seem to remember he had an issue that the valve that switched between the two tanks on his got funky towards the end.  Sometimes had to switch back and forth a few times to get the rear tank to work.

Very well could be. Know how to test it?

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You would need a pressure gauge to hook up to the Schrader valve on the motor.  Check fuel pressure individually with each tank selected.  Fuel pressure low with both tanks is most likely the regulator, low on either front or rear tank then you would need to check the valve and pumps.  The symptoms my dad saw was when switching to the back tank the engine would quit.  The pump could be heard running but fuel pressure dropped off.  If he ran the switch in the cab back and forth a few times the selector valve would finally switch enough to let the fuel past and the truck would run.

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