Bogging on acceleration

[Anonymous]

Hmm...I'm going to try and explain this a best as possible, so hang on everyone.

I've notice after my engine has warmed up the engine bogs and dies, sometimes, after I depress the accelerator pedal. I have to adjust the climatic choke in order to correct this problem. But heres my question...why does this happen only after the engine is completely warmed up? It does not do this when the engine is cold.

Oh, I have a rebuilt Carter YF.



-Chris

 

[Anonymous]

Sounds like you have a rich condition possibly the mixture screws. You wouldn't notice it when the engine is cold because it runs rich cold anyway but once it's hot and the choke is off if the mixture screws are to rich you will experience the engine stumbling or dying as you take your foot off the pedal.

 

[CZLN6]

Howdy Charis;

Bogs can be caused by too much gas or not enough. Given your scenario, I'm inclined to think that it is time for a carb rebuild. As hindle said, the choke is covering the condition when cold by creating a rich/choking situation, but when the engine warms and leans out the accelerator pump in the carb has to cover the lean/acceleration condition.

The low speed air screw can be used to help cover this transition whether it be due to lack of or too much fuel. Check you plugs. If they are dark and sooty- too rich. If they are white and chaulky- too lean. To help cover a poor accelerator pump by enrichening the low speed air screw is not going to help your economy.

With the engine warmed up, but off, remove the air cleaner and look down the carb using a flash light, to see if gas is being squirted into the venturi when you work the throttle. If you see some it indicates that the accelerator pump is working. If you don't it is not and nothing short of a carb rebuild will fix it.

How old is the rebuild? What quality? Is there an accelerator pump adjustment on a YF?

Late initial advance setting will add to this problem.

Adios, David

 

[Anonymous]

yeah, after putting in a new (used) carb...it was EVIDENT that my accelrator pump wasnt work properly...

worth a look at

lot of carb questions today, huh?

 

[Anonymous]

Well, the YF was rebuilt my me earlier this spring. The engine seemed to be running alittle rough. After rebuilding the engine and transmission, my thoughts were the induction. Worked out well but it just seems odd that I have yet to be able to fine tune the choke.

All of the other adjustments do effect the engine (idle adjustment screw, a/f mixture screw and choke). Don't know about any adjustments for the accelerator pump. Maybe these YF's are a little fussy to mess with...just my thoughts or maybe I'm just expecting too much. A nice diesel idle would be good. Ya know, little or no vibration.



-Chris

 

[Anonymous]

when i bored out my carb and made the jet bigger i needed to tighten the accelerator pump screw about 3 or 4 turns...it bogged before as well, but now it is absolutely perfect... your YF should have this screw..its a small hex by the top of the accelerator pump...u just gotta pull off the top of the carb a few times to make sure u get it right...my engine purrrrrs..i dont have a single miss or hiccup in idle or drive, and it sounds sweet when climbing a hill at low speeds....cause when i drove my car to work at some peoples place today, they thought it was a vee-eight 8) ....i think the stock setup for the idle mixture screw is - tighten it all the way, then back out 2-3 turns. i have mine out about 5 turns...different carb setup though too...choke shouldnt be a big deal though, my choke isnt setup right now and doesnt engage (easily remedied when i need to though) but i can turn on the car right in the morning and drive away..no choke and no warmup.

 

[Anonymous]

Well, I pulled my spark plugs tonight - black! This may explain my "not to smooth" idle and possibly my bogging, maybe?

Anyway, I looked for a hex shaped screw near the accelerator pump inside the carburetor and I couldn't find one. So, what's next? How can I lean out my air/fuel mixture ratio on this carburetor?

I'm timed at 12 degrees and I bought a 180 degree thermostat just last week. The only vacuum lines (new) I have are to the C4 and the advance port canister on my DS II dizzy.

I'm starting to lean again towards a 2bbl setup. Maybe a 5200.

Help.


-Chris

 

[Anonymous]

this is the YFA...it was in the same category as the YF for the diagrams...how much different is the YF then?

 

[Anonymous]

Well, here is my YF...

and the inside...

Now, are you refering to the small Philips screw next to the accelerator pump as its adjustment?


-Chris

 

[Anonymous]

Yes i am...sorry, mine is hex. but thats the one that i adjusted.