390 miss
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390 miss
I have a 73 f-250 with a 390 pretty much stock exept rv cam and holly 650 dp.
the engin has about 10,000 miles on it every thing redone.
every time I pull my my boat up a real steep grade it will do fine up to a point then will start missing and will have to slow down alot and downshift. At first thought it might be jetting, had 62 in primary and 72 in secondary. Changed primarys to 65 no diffrence so bumped them up to 68 still no change. Any help out their????
the engin has about 10,000 miles on it every thing redone.
every time I pull my my boat up a real steep grade it will do fine up to a point then will start missing and will have to slow down alot and downshift. At first thought it might be jetting, had 62 in primary and 72 in secondary. Changed primarys to 65 no diffrence so bumped them up to 68 still no change. Any help out their????
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Stick around someone will be by shortly to answer your question.
We are happy you have chosen the best source for Fords!
Enjoy FTE....and
JOIN CLUB FTE -SUPPORT THE FORUMS!
…..See you on the boards.
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It sounds like a bad carburator. Check all setting on carb and verify to specs. or Try installing a rebuild kit or new carb.
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Isn't this obviously a fuel delivery problem?
Rule out vapor lock by checking the accelerator pump at the exact time this happens. If there is "air" coming out the shooters when you pump the throttle (or a mix of "air" and gas), you are vapor locked.
If that's not it, you just aren't getting enough fuel to carry the load for a long enough period of time.
Check filters, change pump, check strainer in tank (in order of increasing difficulty)...
Or, do the filter(s) before you try the trip again, and then check for vapor lock, and then if it's not fixed, change the pump and check the strainer in the tank.
Rule out vapor lock by checking the accelerator pump at the exact time this happens. If there is "air" coming out the shooters when you pump the throttle (or a mix of "air" and gas), you are vapor locked.
If that's not it, you just aren't getting enough fuel to carry the load for a long enough period of time.
Check filters, change pump, check strainer in tank (in order of increasing difficulty)...
Or, do the filter(s) before you try the trip again, and then check for vapor lock, and then if it's not fixed, change the pump and check the strainer in the tank.
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From: Long Island USA
Originally Posted by krewat
Rule out vapor lock by checking the accelerator pump at the exact time this happens. If there is "air" coming out the shooters when you pump the throttle (or a mix of "air" and gas), you are vapor locked.
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Originally Posted by frnk73f250
I have a 73 f-250 with a 390 pretty much stock exept rv cam and holly 650 dp.
the engin has about 10,000 miles on it every thing redone.
every time I pull my my boat up a real steep grade it will do fine up to a point then will start missing and will have to slow down alot and downshift. At first thought it might be jetting, had 62 in primary and 72 in secondary. Changed primarys to 65 no diffrence so bumped them up to 68 still no change. Any help out their????
the engin has about 10,000 miles on it every thing redone.
every time I pull my my boat up a real steep grade it will do fine up to a point then will start missing and will have to slow down alot and downshift. At first thought it might be jetting, had 62 in primary and 72 in secondary. Changed primarys to 65 no diffrence so bumped them up to 68 still no change. Any help out their????
