The Stovebolt Site Forums The Shop Area Engine Shop W1 carb adjustments

Probably a stupid question

216 with W1 , Starts fine with choke,after warm up choke off
(manual choke)
cannot use accelerator without bogging and stalling.
a slow push gets some rpm,that's all
pulling the choke get a lot of rpm,without bogging

just excited it is running with temp and oil pressure gauge working
almost done

Vacuum leak? Take your unlit propane torch turn it on and pass it around the carb while the truck is running. If it revs up you have found your leak. If that's not it you may need to clean the carb and adjust the float level.

Sounds like the accelerator pump has quit working. While looking down the throat of the carb, open the throttle quickly and see if any fuel sprays. If yes, could just need a carb cleaning, if no, then carb cleaning with new accelerator pump. Different venders sell the W1 kits, just be sure to get one that fits your carburetor since there were different models made.
Joe

Not certain I totally understand the problem:

Will the engine not rev up to WOT period, even with choke; or will the engine rev with choke, but not without choke.

As Joe mentioned, POSSIBLE accelerator pump issue. EASY TEST FOR BAD ACCELERATOR PUMP:

http://www.thecarburetorshop.com/Troubleshooting.htm#Acceleratorpumps

Other possibilities:

Distributor advance not functioning (should be able to determine this with a timing light).

Insufficient fuel delivery to the carburetor.

IF YOU NEED TO REBUILD THE CARB, having the tag number of the carb to supply to the kit vendor is the best way to get the correct kit. If the tag is missing, this link may help you identify the carb:

http://www.thecarburetorshop.com/CarterChevroletW1.htm

Jon.

I will try those suggestions, carb was rebuilt , not sure about the distributor advance

engine revs with choke ,but not with pedal

darn
some of these checks are hard to do alone...

ok,
I believe it is the accelerator pump, now to rebuild or replace.
crap
now to find kit or carb

Kits are easy (unless it is a 1949, then they are expensive!). You just need to identify your carburetor. The link in my previous post should help.

Now. Your accelerator pump MAY be bad, but that is NOT keeping the engine from reving up.

During WWII, many farmers in this area DISCONNECTED the accelerator pump completely to save on fuel. Remember, fuel was rationed. The engines still ran fine.

Jon.

Jon,
Engine runs nicely at idle and will increase rpm's with choke after warming up.
only when using pedal does it bog and try to stall.
A slow push on pedal does allow some increase before it bogs.
thanks for the advice,I need the help.

( I know it says"shop shark",that just means I talk too much)

OK - as stated in previous post, accelerator pump MAY be bad, but not the issue preventing the engine from bogging after it starts to take fuel.

If everything else is normal, the engine WILL run at wide-open-throttle with the accelerator pump REMOVED from the carburetor!

(1) compression test
(2) ignition test (find a clip-on volt meter capable of 20k volts, and measure voltage at the plugs, both cold and hot).
(3) fuel delivery system test

If all of the above are NORMAL, and engine still will not run at WOT, time to go through the carb.

As stated in previous post, VERY COMMON during WWII for Missouri farmers to disconnect the accelerator pump completely. When fuel is rationed, no need to waste it with the pump.

Jon.

Have you played with/ checked the timing at all? My 235 with a Rochester displayed similar symptoms that improved a bunch once I advanced the timing a bit.

I have tried the timing at different points,what I reallly need is to get the wife to operate the throttle while I check things.

1) compression test, will do,rebuilt engine
2) not sure how to do this,have meter and timing lite
3)how should I do this ?
carburetor

so I tried something I could check by myself
hooked vacuum gauge to distributor advance line
when I started truck ,I got approx 20 reading
kicked idle down and got 15
when I increased throttle, vacuum increased to just over 20 ,then dropped off
( using Mighty Vac brake bleeder system)

I am getting like "Marvin" from Hitchiker's guide to the Galaxy.
" I talked to the computer ,it hates me"

Sounds like its functioning normally to me. The source of that vacuum is below the throttle plate. When you open the throttle plate, vacuum will increase. This is opposite to what happens with vacuum above the throttle plate (like the windshield wiper motor port).
Carl

so I readjusted timing and didn't get much results

Then I let some Marvel Mystery seep into accelerator pump rod and into carb

finally some throttle, rebuild kit coming tomorrow,and will recheck timing ,need to crawl under and get to flywheel to clean timing ball,want to make sure I am looking at the right thing

Update, it was the Carb accellerator pump, all better !!!