i have a 87 ford f250 with a 351 Windsor and a holly 4 barrel i was driving 45mph and all of a sudden it wont go over 25 to 30 i pulled over and checked the carb plenty of gas in the filter but the choke plate is stuck wide open do you guys think that could be the problem that i need a new choke? O by the way no water in the oil cap or no water on the dip stick help please reply to my email at sbreide471@msn.com

 

Is the stock cat still on the truck by chance?

 

hmm i dont understand what cat is

 

The choke being wide open won't cause a loss of power when the engine is warm.
The "cat" is the catalytic converter in the exhaust. A plugged cat will restrict exhaust flow and limit engine RPM.
regards
rikard

 

It happened all of a sudden so i think something came loose i need to look at it Saturday when the engine has had a chance to cool love the advice thanks guys and gals

 

did you hear any popping sounds or other noise right before you started having the issue? (i have had a cat on a Saturn blow apart and plug the exhaust up, no power) and is it an issue associated with speed or RPM?

 

my 87 ford f250 with a 351 w doesn't have a catalytic converter

 

hmm. are there any other symptoms? is it the motor wont get up to speed (RPMs) or its winding up like it needs to shift but wont?

 

No water on the dip stick ... was the old level " high" or about normal? If mechanical fuel pump and it failed the gas ends up going in the crank case.

Does the motor sound like its working hard at the 25 - 30 MPH mark or is it kind of limping along? High rpm or no?

 

no gas in the crank but when i step on the gas pedal the rpm will spike and it sounds like it's sucking air big time the when it idols it sounds normal i did Chang the throttle cable recently do you think it could be sticking that would almost be silly

 

ok i went to check the crank out and no gas in the crank could be a piece of grit in the carb because it fixed itself once ran good for a couple of days then it started again and i replaced the fuel filter sprayed carb cleaner in the choke and the idle gos up and it sounds like its sucking air

 

Sounds like you have a fuel jet plugged up. You can hear the motor pull in the air as the butterfly opens but there is just no fuel to burn........ Check for a weak spark. Maybe once the mix gets to strong you cant make the fire to burn it all.

Take off your air cleaner, with engine running, use some eye protection or a mirror look down the carb and open the throttle about half way. ( if stick shift be sure to block the wheels so it don't roll away on ya.! ) Look and see if your getting fuel down both barrels of the carb. If 4 BBL just look at the main barrels and jets. They should be pushing the same amount of fuel on both sides. If one is weak or no fuel then you have a plugged jet or some other carb problem.

 

Changed the fuel filter lately? May be a good time to change it if not.

 

i changed the filter thanks

 

in the old day's you could take out the old jets clean them up screew them all the way in and then back them out 2 1/2 turns but it turns out the jets are hidden behind the Fuel Bowl Assembly Primary there are a 2 dary and primary jets located in the Metering Body Assembly Primary is it hard to change or pull them out clean them up and put them back.

thanks scott