when 1st started i needed to adjust lifters/rockers etc, no big deal... carb was rebuilt, new distributor, coli, plugs, wires, etc... all was/is new
so just the last few days i just had trouble starting the truck. prior i needed no choke, pedal play or anything and it would fire right up.
so a few days ago i dumped some gas into carb...fired right up but had a wrapping noise... drove for 10 minutes, noise was gone and sounded great. a few days later i tried to start the truck and again, wouldn't start unless i put fuel in carb. Today same thing, fired up after putting fuel in carb and when it starts, it has a significant wrapping noise,but doesn't sound like rocker play to me... after driving it goes away and sounds great, but again still difficult to start.
attached are two videos... 1 right after i start and the 2nd after it has been ran...it's a little windy so i apologize...
The "wrapping" sounds like a lifter tap. From the quiet running in the second video, it sounds like you have hydraulic lifters, and it sounds like the motor needs to run a bit before it pumps up. Try removing the valve cover, starting up the motor, and figuring out which rocker is tapping, and readjust that rocker. It may just be that rocker is adjusted just a bit on the loose side. Remember, hydraulic lifters get some preload on them, not clearance like a solid lifter.
Sometimes, adjusting hydraulic lifters as per the shop manual or other methods of adjusting on a non running motor just does not seem to get the job done. An alternative, is to get the motor running, turn the idle down until the motor is just barely running, and adjust the offending valve with the motor running. I know it sounds counter intuitive but it can be done. After the motor is running quiet again, turn the idle down, back the adjuster out of the offending rocker until it starts tapping. Then adjust back down until the tapping stops, then turn the adjuster in 1/2 to 3/4 of a turn more, a little bit at at time, and re tighten the jam nut. See if that solves the issue.
So are the lifters new manufacture or nos or rnos?
mike... yes, hydraulic lifters... my block is late '58 so it was drilled properly for them.... I'll try and see which one is the culprit and adjust according to what you laid out, thank you..
related to the carb, where should i start? should i adjust the mixture screw to more rich and see if that helps?
also, i'm not running any zinc in my oil? should i be or add an additive to my existing oil?
Sounds to me you may have a lazy fuel pump. Take a wooden dowel or even a long extension press it to your ear, put the other end on the fuel pump and listen. You can also move it around the engine to see where the noise is coming from. Poor mans listening device
I am nothing more then a backyard hacker so I like to eliminate the low hanging fruit. Start with the fuel pump like Harv suggested. If not making a discernible noise, take the valve cover off and locate the troublesome lifter and adjust it. Then, head to the carb again, adjust the idle screw so it’s idling at the correct specification, then adjust the idle mixture, turn in until it stumbles, then back it out a little bit at a time until it smooths out, then a little more. Readjust idle speed, then double check your timing. That should get you in the ball park.
Couple of other things to check. Fuel filter. Also fuel pressure. These carbs don’t like a lot of pressure. They need 3 1/2 pounds minimum, 4 1/2 max. A rebuilt or new pump could be putting out 6 or slightly more. Not really what you want. So I would check the running pressure with an external gauge. Also, double check the vacuum advance is working. If the diaphragm is split or broken, you have a vacuum leak that is just adding insult to injury.
What kind of air cleaner are you running? If one of those little chrome cleaners, your probably adding to your problems. They don’t flow enough air.
Oil, every one has there favorite. Mine has been Brad Penn for quite a few years. 10w30. It’s now called penn grade 1. It’s a semi synthetic. Uses Pennsylvania crude as a base stock (always known as a superior base stock), with a zinc package, and a synthetic additive package. made at the former Kendall refinery in Bradford pa, (home of the zippo lighter. My daughter went to college in Bradford so I know the area), Clings nicely to the rockers over the winter and I have not had any failures with any of the motors I have built using the stuff. I also use their break in oil.
Welcome to the world of aftermarket hydraulic lifters. I have a '53 full pressure 235 which has 10,000 miles on it and does exactly what yours does until it reaches operating temperature, then runs as quiet as a mouse. It has done that since it was rebuilt. I was hoping that it would go away, but it has not. I just let it run at idle until warmed up and live with it.
The issue with fuel delivery: Tell us about the fuel tank. New? Thoroughly cleaned? Don't know? Pull the fuel line from the carburetor and put a rubber hose on the end of it to go into a Diet Coke bottle and turn the engine over with the starter with the ignition off. You should get some pretty decent spurts of gas going into the bottle in just a few revolutions of the engine.
If you do not need to ever use the choke to start the engine, you are running too rich at idle. Adjusting the idle/mixture screw may address this. Pull all of your spark plugs to see what they will tell you. They generally speak volumes. Dry black soot will indicate too rich. Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Gents... so appreciate the input. harv, i'll listen to the fuel pump for any noise and other areas for that matter so thanks for the tip. Ironically today it started fine, so i drove to filler station and again stared just fine. Next to the gym where it sat for an hour and sure enough, needed starter fluid.
to answer a few of the other questions, i'm running the original oil bath air cleaner. also i have a new fuel tank so should be clean. again truck ran and started great but now starts intermittantly. i will replace the fuel filter and as '52 carl stated i'll run a hose into the bottle to look for fuel spurts. i don't even know where/how to begin to check for fuel pressure but i can read up on that. next oil change too i will go with a zinc additive package.
timing light was used and is right where it needs to be as the "BB" or arrow on the fly wheel is on point with the point on the bell housing casting. the tapping sound did is still gone as the lifter must be full and primed still/////
carl... here's a few pics i took today. truck has 323 miles on rebuilt engine and i replaced the plugs 100 miles ago or so....once again she wouldn't start today
The plugs look spotless. I would say that your problem is very likely a fuel delivery issue. Time for the fuel pump test. I recommend that you do the test the next time it refuses to start.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Like I noted to you earlier, you need to check fuel pressure, both cranking and running. Too little or to much pressure are detrimental to getting this motor of yours running right. You might also have to pull the top of the carb off just to check the float level and inspect the bowl for debris. If there is a sintered bronze filter in the carb inlet, you want to look at that also. Clean clean clean and the correct pressure is what you ideally want.
If the pressure is off, the carb adjustment is likely off. So once the pressure is confirmed or fixed, then you can make your choke adjustments, and running idle and mixture adjustments. Once that is done, and the motor is running, recheck the timing and all should be in good order..
carl and dragsix i will investigate further into the fuel issue this weekend.
i did however the last time i started the truck a few nights ago, i did hear a hissing/sucking type of noise while the engine was running and so i found a hose and moved it all through the engine compartment. The noise is coming from what must be a leak where the intake manifold mounts to the exhaust manifold. I don't recall when i did my restoration if i ever removed those two pieces from each other and replaced the gasket. could that be causing the starting issue all the sudden?
It might if the leak is between the manifold and the head. Not enough vacuum signal to pull idle fuel out of the well because it is all bleeding off at the gasket leak. Do you remember if you reinstalled the retaining rings? If not, you want to put them on and use a Rimflex intake/exhaust gasket. Best around, one piece, and seals better then any other gasket.
If the gasket is bad between the manifolds it will not cause a vacuum leak or hard starting. It will be an exhaust leak. Check the accelerator pump in the carb. Look down the throat of the carb with the engine off & open & close the throttle. Each time you open the throttle a squirt of gas should go in to the carb. throat. If that is working pump the gas pedal 3-5 times as you turn it with the starter when the engine is cold. These old carb engines don't work like the late fuel injection engines. George
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne Super In the Gallery Forum
so just an update... i haven't had time to perform any of the tests as suggested yet, but i did take off the oil bath air cleaner and pull the choke. i noticed the butterfly wasn't fully closing so i adjusted the cable. After doing so, the choke fully closes and it starts right up when cold. after driving the truck to engine operating temperature if i shut it off and try to restart, i still have to use the choke for her to start back up. possibly could this be a flooding issue?
If you have to choke a warm engine, it's lean, not rich (flooding is too rich). Use an unlit Propane torch around the carburetor base, intake manifold, vacuum hoses etc. to find your vacuum leak. Then fix it. That hissing noise is caused by air getting into the engine that's not going through the carburetor to get the proper amount of gasoline mixed with it. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I have a 59 Apache with a 235 engine. It runs well when it idles and I rev it up. However, when I put it in gear and start moving it loses power. I have it floored in 3rd gear and can only get up 45 mph. Anyone have any ideas why.
