need to try a different carb again.. i here the YF carbs are good.. i am running 216 ci engine. what model number is best? i have run several roch b's with bad results (boils over leaks, hard starting) ran 1 yf with poor results boiles over.(maybe just that carb) currently running a w1.. works great but man have to crank forever to get it started cold.. any other suggestins?
How is the technicall qualety of the ignition setup (rotor and points? Did you checked the sparkplugs and cleaned the airfilter ?Maybe your old Carter YF should have been overhauled or adjusted some. Look after leaks or failures working.Gasket leaks can give problems to. Carter YF W1 is recommended for the Chevy truck and a carb in good condition normally works great.There is a good thread (carter carb) about the issue this week, you`ll find the answers you need there. Martinius. http://www.thecarburetorshop.com/History.htm https://talk.classicparts.com/showpost.php?p=35554&postcount=44 http://www.carburetor.ca/carbs/tech/Carter/Y-index.html
Try this before going on another carb hunt, especially since your present one is good except for cold starting. Take the air filter off and set it to the side for several cold start sessions and then prime it. If it fires right up when primed it is a fuel drain back problem not the carb. An empty plastic quart oil can with a small hole drilled/punched in the screw on lid makes a great squeeze bottle for priming. My 37 Buick has been this way for 20+ years until I gave up and finally put an electric pump back by the gas tank. I only use the electric pump for maybe 30 seconds to push the gas to the carb for starting and then the regular pump works fine. It would fill a page to list everything I tried to stop the drain back, all to no avail.
I think the float level has something to do with the drain back problem. You might find out what the specs are and try that. http://www.carburetor.ca/carbs/tech/index.html here's a link that might help. good luck!!
thanks all.. I agree the cold start could be a fuel drain back problem.. the fuel filter glass bowl goes empty after sitting.. I replaced the fuel pump because i thought that may stop the drain back problem.. does any one know how to correct this? is there some kind of check valve i can buy or something? I dont know why i was having the boil over problems with the YF and several Bs.. I checked everthing, replaced the heat isolator.. checked an replaced the heat riser.. all been timed and valves adjusted .. floot levels checked, and adjusted to spec,, and below spec to make it stop.. no holes in floats etc.. carbs rebuilt by me.. even bought one rebuilt by others just to be sure.. LOL Anyway the w1 on it now works great.. and truck runs great.. except.. cold start... man you think your batterys goin to die before it starts crank crank crank.. I heard the YF's start right up
it is all stock, 216 ci., new points, rotor, spark plugs etcc.. all timed and valves adjusted.. runs great with the w1 once i get it started.. with the rochestor b's and the YF it would strt up much sooner.. but within 15 min of driving it would they would boil over and leave me on the side of the road waiting for it to dry out enough to start again and get back to the garage .LOL
Downdraft YF carb float settings ect. Mot 1982 Hi again What production number (tag) does the carb have? Does it have an autmatic choke (dashpot) or is there a manual choke ? Incase it has the aut.choke , be kind to look if it has the stovepipe that must be installed on the backside of the aut. carb. going towards the exhaust. Is this the right pump for 216 engine or do you have installed an other model pump maybe for 235CI , check pump function when at cold start and when the gasolin is under pressure after the engine has started . Let it run until it becomes hot (10 min). Look if the gasolin floats normally through the glassbowl if you have one? If it does there is nothing wrong is with the pump. Normally the right float level setting should keep the gasolin in the carb. Are you shore this is correct , check this out ? YF carb. standard Settings; Float setting 9/32 inch (Gauge T109-126), use mesuare and check out. Idle adjustment Screw setting 1 to 2 turns open , check out. Martinius.
Thanks, Big Tim, but he float level has been multi-checked and also raised/lowered in 1/32 inch increments---all to no avail. The rubber and steel lines have been replaced, the end of the line that screws into the carb capped, the (empty) tank pressurized, and the entire length sprayed with soap solution for leak checking which yielded nothing. A capped non leaking line should hold a column of fuel indefinitely. I couldn't find a Viton tipped needle, just brass or steel, so I made my own. It will hold eight PSI when closed by just the float pressure. To completely take the needle/seat out of the equation I screwed one end of a very good ball valve into the float bowl fitting and the line from the tank onto the other side of the valve. When it was not going to be run for a week or so I would close the ball valve (rated at 125 psi) and then open it just before cranking. Still drained back, hence the electric pump. A problem will make me take the bit in my teeth and go to any length to solve it but this one got me. For the last number of years the electric pump has worked fine for priming so I shouldn't gripe but every time I flip it on it gets my brain to churning as to what is causing the drain back.
I feel your pain Evan, I have 2 AFB's on my "61" and when it sits for a few days it does the same thing. The rebuild instructions say it has to do with the float level but I have yet to figure out how to cure the problem.
Mot1982 : Just for grins , try holding the foot feed to the floor and the choke fully closed when you cold start it ~ this increases the intake vacuum signal into the float bowl and helps the fuel pump prime it faster... You say it's boiling the fuel out after you drive it a little bit but you didn't mention the engine overheating.... I wonder if the fuel pump needs attention due to leaky pump valves and low volume/pressure ? . I drive my '49 with 235 into and across Death Valley , the Rochester 'B' series junk box carby has NO heat insulator installed (long stupid DPO story there) and it never , ever boiled the fuel out once it's running , not even in 125* F heat fully loaded . Yes , it boils dry in about 2 minutes once I shut it off and the engine heat soaks but full choke gets it running again quickly . I'm just trying to help you think outside the box here...
nate, no engine does not over heat at all.. the Bs just boiled over.. only when driving.. it could idle for ever with out problem... i had 1 yf on it and it did the same.. now i have a w1 on it and no problem at all runs great.. but man oh man does not like to start cold.. the gas does drain back i know cause the fuel filter goes dry over a few days. yep i thought it all could have been the fuel pump.. so i replaced it.. no change... arrg..
Try and bend a pee trap in the line as is on sink and tubs to stop sewer gases from entering the home in front of a glass bowl filter or a back flow behind a glass bowl filter, or just a glass bowl filter in line but some what higher than the carb inlet. I have used putting a full circle in the line just before the carb. These may not work for you but have worked in the past for others
Glassbowl filter mount. I like the idea very much and the solution could give a better outcome using nature laws with contineously fluid float (the siphon effect) . Maybe you could use flexible copper tube instead of steanless steel ? Martinius.
Warning ! Fire danger ! Never , EVER use copper tubing in the fuel system ~ over time it work hardens from normal vibrations then it cracks and leaks...... A Fuel fire will burn your ship of the highway to the waterline before you can call 911 .
