I have a 1953 Merc Flathead V8 and am having trouble getting it to start. I need to put a little gas down the carb to get it started. Once it is running it runs fine and idle good.
I just have trouble getting it to start. I have put a new gas tank, gas line, fuel pump and have rebuilt the card. It seems like it does not get gas to the motor until it is running.

I would appreciate any tips or direction of things to check. Thanks

 

Did you rebuild the carb or have someone else to it? Sounds like there could be a passage way in the carb that might have been overlooked. I just recently got a '53 Ford flattie running. I could tell it wasn't getting much gas so I pulled the jet out and ran a welding tip cleaner through them. After that I could see gas coming out of them. The fuel bowl in the carb was filled with crud. I did a quicky carb rebuild just to get the engine running.

 

I rebuilt it myself and cleaned it out real good but that does not mean I did not miss something. I did not run any thing through the fuel passages in the carb when I rebuilt it. Would the idle mixture screw position affect this? I have them both set at 1 turn out. This is where the manual says to start them off at.

 

Could be as easy as adjusting the mixture screws. I'm not an expert, all I do is read the manual and try to figure out what could be wrong. If, as with the engine I have, there was crud in the bowl and your engine sat a while the crud could have migrated through the jets and plugged them up, only allowing a small portion on fuel to get past. Once the engine is running there could be enough vacuum created through the carburetor to such gas through. That's my thought but I'd check the mixture screws first, that's the easiest thing to do. Always, start at the easiest thing.

 

If you disconnect the fuel line at the carb, stick it in a bottle, and crank it over, would the pump push enough fuel through? If the answer is yes, then it could very well be a carb setting. (cam lobe is not it since it runs fine when it gets going) If the answer is yes, and the carb is not the problem, then I'd suspect a firing issue (simple to check if you have a sparkplug tester), or lack of enough vacuum.

My '53 tractor has the same issues. I believe it vapor locks since the fuel line runs up and over the (bigger than stock) battery, going against gravity, like it should. But at the same time, I get an occasional non-fire, due to old wires being cracked.

 

Hi and welcome to the site,
I am no expert and it has been a lot of years since I've had anything to do with flat head V8s. I remember that some times the push rod between the cam and the fuel pump will wear and make it appear to have a weak fuel pump. As a temporary repair I have simply packed a small amount of tinfoil in the cup on the fuel pump arm (about an 1/8") to lengthen the push rod. I have also seen push rods that some one brazed the rod and ground it back to proper length. Of coarse this would only be temporary and a new push rod would be the way to go if this is your problem. Like some one else suggested take the gas line off and see if the pump is putting out enough gas or use a pressure gauge. If the pump seems weak look into the push rod thing.
Again I am no expert so hopefully some one with more expertise will come along with better advise. Good luck.

 

How long does it need to sit before it becomes hard to start? If it re-starts after sitting for 1/2 hour with no problem, but cranks a long time after 4 - 6 hours, I'd expect the power valve is leaking the fuel out of the bowl. The PV's in rebuild kits nowadays are really for a Holley 2110 series which uses a slightly different PV. It can be hard or impossible to get the 2110 type PV to seat in the Holley 94 base, so the gas leaks out of the bowl after a while.

There are a couple of ways to check for this. One is to just pull the top off the carb after it has set for a day. If the bowl is empty, that's likely the issue. You could also take the fuel line off the carb after it has sat overnight and try to fill the carb with gas from a squeeze bottle. If it starts right up, there you go...

 

Guys
I appreciate the input and I will check these this weekend. I am leaning towards the power valve suggestions as I did use a new rebuild kit and it says that it is for a Holley 2100 or 94. I will give this a try. Does anyone know if you can get the power valve that is correct for a Holley 94?

 

Charlie Price's Vintage Speed | World's largest supplier of 50's – 60's Style Hot Rod fuel systems has the correct ones.

 

If it runs just fine with know issues like hesitating under hard acceleration or dieing out around a corner than I would not think there is anything wrong with the pump. If my Y Block sits over night or longer I use a squeeze bottle to fill the float bowl through the big air horn sticking out the carb intake. Pump her twice pull the choke and she starts right now. Just let her sit over night. Than while looking down in the carb jack the throttle open and shut a few times. If she don't squirt enough gas to look like it's flooding than the power valve (pv) is nonoperational.

 

Hi Mlis, welcome to the forum.

If you go with replacing the fuel pump push rod as suggested by Old Ugly, you might find the following info of interest.

I recently got a fuel pump push rod from Dennis Carpenter on eBay. Mine had just over 3/32" wear after 30k miles, so I decided to replace it. It was for my late '49 239cu.

When it arrived I noticed the bag it came in said "Made in China". I've had some bad experience from "Made in China" before, but figured Dennis Carpenter would not risk their good name if it were not a quality part tested by them to protect not just their good name, but their loyal customers.

I installed it, fired up the engine and could tell immediately that something was wrong. After 4 or 5 minutes of rough idling, it died. I could tell something grabbed the cam, it actually froze the cam on the rise of the eccentric when it died. I pulled the pump, popped out the rod, and it was obviously not to spec. Just a few minutes of low idle showed wear from the cam, and I could see how it grabbed the cam when it died.

I contacted them with my complaint, and was told that they had sold 587 from this lot (Sept 2011 to the present) with no complaints yet. The fellow that knew the specs, Ron Harkey, was out of town till the following week, so I started calling around to other top name suppliers to get the spec on the push rod that they offer. Nobody I contacted could provide the specs. I even tried Little Dearborn and was told that they didn't have the specs, and even if they did they would not supply them, it was 'privy' info. This it ridicules, Henry Ford didn't hide specifications, he was proud of the quality. Now we have people promising the same (if not better) quality parts that are either hiding the numbers or just don't know them.

I was able to easily scratch the surface of the supposedly carbon-hardened cam end portion with a file. I then easily stamped the word CHEAP into it. As for appearance, they didn't even try to fake it, the whole rod looked like aluminum. Carbon hardened steel has a look to it, a slightly darker bluish tint that depends on the depth and quality of the hardening.

We ran it on the Rockwell hardness tester. You won't believe this. The cam end was tested in 2 places for accuracy. Rc-18 in one, and Rc-19 in the other. Should have been minimum 40 on the Rc.

I felt like I'd lost a friend in Dennis Carpenter, a good and trusted name, thinking they sold out to China along with so many other good names. They immediately refunded my money, no questions asked. I told them that they should notify all customers with push rods from that lot.

They just now got back to me with their findings on the investigation. Most of the rods they tested were way below spec, falling in the low to mid 20 range on the Rc, meaning their supplier in China was pulling a fast one. He said they should be about 50 Rc. He also said that the past two days were spent notifying their customers about it. I asked him about the other push rods, he said only the fuel pump push rod was made in China, and that they are thinking of making them locally now. Though I'm sorry this happened, I was happy to see how Dennis Carpenter responded, stepped up to the plate in (1.) acknowledging the problem, and (2.) taking steps to rectify it. This might have been a lesson to them as well.

I might put a webpage together with some images. If I do, I'll post back when it's ready. Take care, keep your eyes open out there.


Moosemunch

 

I realize we have an old thread here. I've seen the cup fitted with a piece of leather and it ran for years.

 

I hate it when the OP don't come back and let us know if they solved the problem. It helps to know so the next guy has a chance of reading the thread and solving there's.

 

That is similar to my experiences with DC, as far as follow-up on problems. Unfortunately, it is also similar to many problems with Chinese-made stuff, no QA/QC. Thanks for sharing!

 

Not to preach but only to add something to consider. I realize you received a defective push rod but the slow idle may have contributed to the early failure. I believe current break in procedure for a flat lifter cam engine is to start and immediately bring the engine to a very high idle so as to flood the cam and lifters with oil and to keep it at very high idle for thirty minutes. More important with the oils we get today that lack the ZDDP in sufficient amounts for these old engines. I would consider the fuel pump drive cam and the push rod would be flat lifter.