Jump to content

What is the correct starting procedure for the 401 Nailhead?


bepnewt
 Share

Recommended Posts

What is the correct way to start my (non-original) 425 Nailhead on my '64? When the engine is cold, it takes about 30 - 45 seconds to start it. Once it's warm, it fires up immediately.

I just read this thread that was recently updated:

http://forums.aaca.org/f177/troubleshooting-hard-starting-64-a-292435.html

At first, I thought I just didn't know how to set the choke or whatever I need to do for a cold start. After reading that thread, maybe there's more going on than that.

So... assume I don't know anything about chokes, how much gas to pump while cranking, etc. and please describe the proper way to crank over my cold 425. I've been in fuel-injected cars waaaay too long.

Thanks,

-BEPNewt

Edited by bepnewt (see edit history)
Link to comment
Share on other sites

Thats consistent with starting my 65 401, particularly if you leave the car for longish periods without use, as I do, 2 - 3 weeks or so. Its fine when used regularly or when warm.

The fuel evaporates and its a large carb and large engine.

Hope this helps.

Link to comment
Share on other sites

I'm with John. My '60 takes maybe 10 seconds cranking if it hasn't been started for a few days or more. This is due to modern fuels evaporating and losing their octane "flash". If it has been driven in the last day or so, it starts instantly hot or cold - especially after the carb was rebuilt.

Link to comment
Share on other sites

Wouldn't an added electric fuel pump solve this issue by priming the carby prior to cranking then switch off and leave it to the manual/factory pump to do it's thing?

Not original I know but it would save the starter and battery from being overworked as 30 - 45 seconds would put a lot of strain on a 47 year old starter.

Link to comment
Share on other sites

If you're completely unfamiliar with carbureted motors it could take 30-45 seconds to start but in my experience no engine should ever take that long to start. You may have something else wrong with your car possibly needing a carb rebuild or timing adjustment. Some extra info could clear the water like how long does it sit between starts and how old is the engine?

If you're confident you have everything lined up and adjusted correctly i will usually pump the gas about three times and hold down the accelerator just slightly then fire her up letting it idle a little high for no more than ten seconds then she's ready to fully warm up on her own.

-Mario

Link to comment
Share on other sites

  • 6 months later...

Like a bad forum member, I never came back and posted the results.

The method Mario mentioned didn't work for me. It still took a long time to start the first time and then after that, it starts easily. It's still exhibiting the same behavior now, 6+ months later.

I'm interested in the Electric Push Pump solution and I have a couple questions about it.

1) Does anyone have link to the correct item I'd need to purchase?

2) How hard of an install is this?

-BEP

Link to comment
Share on other sites

Brian-

I have a small electric fuel pump on my '63 Riv, expressly for the priming purpose that you describe. It is on a push-button switch that I depress for about 30 seconds before cranking. You really can't over do it. Once the carb is full, the float valve will stop more fuel from going in.

I placed the pump under the car, up front on the passenger side, right where the steel line ends and the rubber fuel line attaches. It is easy to run a rubber line from the steel line to the pump inlet and then from the pump outlet forward to the mechanical pump.

The mechanical pump will pull fuel through the electric pump. The electric pump will push fuel through the mechanical pump. They can peacefully co-exist.

I am not sure of all the reasons we need to refill the carb bowl before starting. I suspect that some of it is fuel evaporation. The engine is hot and the carb is sitting right on top of it, cooking. This can be especially true if you have any difference in restriction down the exhaust system between your dual exhaust. Any imbalance at all causes hot exhaust gases to cross over through the intake manifold warming passages. (See shop manual.)

I suspect that today's fuel, with alcohol in it, will have a lower boiling point than fuel did in the 60s. So the engine heat will boil more of it off.

There are some very small passages in these carbs that are designed to stop fuel percolation (see shop manual). If these little openings get plugged up by fuel gum, the hot carb will percolate liquid fuel out of the bowl and into the throat. A quick spray with carb cleaner opens them right back up.

I have also observed on my car that gas slowly drains back from the carb down the fuel line to the mechanical pump when the car sits a long time. I put on a new mechanical pump and it still did it. It takes some cranking to push fuel back up and into the carb.

There are some small plugs on the base of the AFB that have been known to leak fuel slowly out the bottom. I checked mine and they have no staining, so I think they are sealing.

As to cold starting procedure, if your carb is adjusted to the specs in the shop manual, the best way to start it is using the procedure in the Owner's Manual. I do not use their instructions for a hot start, though. They say "depress gas pedal about 1/3rd and crank" or something like that. This will easily flood a hot engine. Just turn the key on a hot engine and it should restart. If it does not start after a few seconds of cranking, stop, count to 10, and crank again. Stepping on the gas a tiny bit while cranking usually helps if you crank twice without touching the gas and it still won't start.

Hope this helps. Sorry it's so long.

Link to comment
Share on other sites

Great information, Jim. Thanks for taking the time to spell it out.

I'll do a search on the web for "electric fuel pump" to see what I can come up with. If anyone has a suggestion as to what one to buy, I'm all ears! Well, and some belly, and an extra chin and...

-BEPNewt

Link to comment
Share on other sites

Brian,

Let us know if you find or install an electric push pump, and what kind it is. I am also interested in doing one. The little reading I've done suggests that you need to be careful not to put a high pressure pump on that was designed for fuel injection, but one that is in the same pressure range as the mechanical one.

I would like to do what Jim does and just use it to prime the well, and then let the mechanical one take the load after. I saw a uTube video showing a '40s Buick with such an electric pump on it and it started about the same as a modern fuel injected car, from cold. I think that we be awesome to have.

Link to comment
Share on other sites

As has been stated this is a common problem with any car that sits idle for a prolonged period of time. Jim`s advice is great and will no doubt cure the prolonged cranking issue but try the following first and see if it works for you..

It is true prolonged cranking can overheat the starter and add unnecessary wear and tear but a little cranking after an idle period is not all bad. I dont mind a few extra seconds of cranking as it gets the oil pressure building for initial startup.

First item to check is the accelerator pump in the carb. If the pump is not providing a good sustained shot of fuel this will not only cause excessive cranking on cold startup but a definite bog when accelerating hard even after the engine is warmed up.

After the engine is up to temp and the carb bowl is up to level take off the air cleaner and look down into the primary(front) side of the carb-engine off !!! Quickly open the throttle as if jamming the accel pedal to the floor and look for a healthy and sustained shot of fuel from the primary nozzles located in the upper air horn in the center. The nozzles project into each barrel from a central point which looks much like a battleship gun turret.

If there is no accel pump shot the carb needs work.

If the accel pump checks OK there is a method I use which can reduce cranking time.

Crank the engine for about 5 to 10 seconds. At this point most folks depress the pedal to the floor once or twice to set the choke but because there is a less than an ideal level of fuel in the bowl this does not provide enough raw gas in the manifold to initiate starting. Instead, try depressing the pedal 5 times or more. Although there is little fuel in the bowl and the accel pump shot volume is diminished, pumping the pedal excessively will usually result in enough fuel in the manifold to get started, or at least get the engine to turn over a few times and help fill the carb bowl. If the car tries to start and run but dies, pump the pedal 5 times again, remove your foot from the pedal so the choke is completely closed, and the engine will usually spring to life with enough fuel in the manifold to stay running.

Works for me. Also a good idea to keep a trickle charger on the car if sitting for a few weeks or longer to provide a healthy spark. Have fun,

Tom Mooney

  • Like 1
Link to comment
Share on other sites

Thanks for the added info, folks. I appreciate the Pic.

If I end up adding a push pump, it will be next year at the earliest. There are other things that are higher on the Prio-List at the moment.

The Riv will probably sit for 4-5 days now, so I'll test what you suggest, Tom.

-BEPNewt

Link to comment
Share on other sites

The thread you referenced was mine, I went back and updated it.

http://forums.aaca.org/f177/troubleshooting-hard-starting-64-a-292435.html

Turned out that I had to add a ground from the negative battery to the fender. Even though my spark tester (in open air) would spark, it must not have been enough current to spark in the cylinder. Its been several months and the car fires right up - even after sitting a few days. I also added some tests you can do to determine if its electrical or fuel related.

Be sure to do a compression and spark check, if the compression is low - you will be chasing your tail looking at other things....

To see if the pusher pump will help, dump a few ounces of fuel down the throat of your cold engine. If it fires right up - then the carbs may be drying/leaking. If its still hard to start, the pusher pump will be a waste of money.

Good luck!

Link to comment
Share on other sites

I tried your technique and it worked very well. I've always had trouble starting after it sat several days. Using this process it fires up and stays running the first time. I think it sat for 1 week before this, so it was a good test.

This worked for me, too. I need to let it sit a little longer, though, to test it "for real". Thanks for the info.

I still plan on doing the other tests Tom mentioned at the beginning of his post and deciding from there where to go with this.

-BEPNewt

Link to comment
Share on other sites

  • 3 weeks later...
This worked for me, too. I need to let it sit a little longer, though, to test it "for real". Thanks for the info.

I still plan on doing the other tests Tom mentioned at the beginning of his post and deciding from there where to go with this.

-BEPNewt

I've let it sit longer now twice, about 5 days each time, and it didn't work.

Next will be doing the test Tom suggested where I shut the car off after it's warm and watch the fuel coming in when the pedal is jammed to the floor.

-BEPNewt

Link to comment
Share on other sites

Brian,

Each pot in these engines at over 820 CCs is larger than a mid size motor cycle engine. This and the rapid evaporation of modern fuels and lack of regular use ensures that even when your accelerator pump is working properly getting enough fuel into the carb/s and then to the cylinders means a lot of cranking before you have enough to light the fire.

There really is no way to avoid this issue if your car sits for long periods, as mine does. You just have to keep pumping until you get enough fuel up. I give my starter motor a break so I dont overheat it and you do need a strong battery.

Unfortunately, the only bulletproof solution is an inline push pump. I intend to add one to my car, but manually operated so that I just use it for priming, a second benefit is that if it suffers from vapour lock as they sometimes do after stopping on a very hot day, the electric pump will deal with this as well.

My 48 Caddy, which is 6 volt, has an electric pump and an optima battery and that big old side valve is easy to start anytime. I just turn it on and let it run until its primed then crank it with a couple of pumps and it starts easily.

Good luck.

Link to comment
Share on other sites

Unfortunately, the only bulletproof solution is an inline push pump. I intend to add one to my car, but manually operated so that I just use it for priming, a second benefit is that if it suffers from vapour lock as they sometimes do after stopping on a very hot day, the electric pump will deal with this as well.

Appreciate the input, John.

I imagine I will end with a push pump. After I do the different tests people suggest and collect data, that will probably be the solution.

At that time, I'll collect as much info on the pumps as possible and buy one that makes sense. I just hope they are easy to install. I wasn't raised working on cars, so anything I can do myself is fun for me because I learn something in the process.

I got my driver door slightly adjusted today and it helped. The door skin is a little loose and needs some adjusting and that will help even more. Even the little things like that get me smiling when I do something myself that improves the car in some way!

-BEPNewt

Link to comment
Share on other sites

  • 1 month later...

Posting again. The one I just posted got lost in the ether.

I'm pretty sure my problem is the choke. Twice in a row now after the car has been sitting for an extended period, I was able to get it firing in under 2 seconds.

I'm attaching a pic of the carb with a red arrow pointing at what I assume is the choke. The last 2 times I started it after resting a while, I first moved the throttle a little with my hand and pushed the choke so that it was held open by the throttle mechanism. I got in the car and started cranking and it pretty much immediately fired.

I don't think the choke is getting set the way it's supposed to, but I'd like a quick explanation of how to correctly set the choke before starting the car. I though you depress the accelerator pedal to the floor and let it up and that should set it. Is this correct? If not, what is the correct way?

Thanks. Almost there...

-BEPNewt

post-72864-143138758506_thumb.jpg

Link to comment
Share on other sites

Yes, your "press the pedal" to set the choke procedure is correct.

I suspect your choke mechanism needs a bit of adjusting, or the linkage and little piston inside the choke housing needs to be cleaned for smooth operation. Do not oil any of that stuff.

Link to comment
Share on other sites

Thanks, Jim.

I had my wife sit in the car and depress the pedal and let off of it once. The choke never moved. If I move it with my finger, it goes back to its resting position.

I recorded me moving it with my finger and letting it go a couple times. Then I opened the throttle and let it go. There is a little resistance on the choke when I move it with my finger, but not a lot.

The engine hasn't been started in about a day and it's about 45* in my garage.

Please let me know what you notice isn't working properly.

Carb Choke - YouTube

Thanks, as always...

-BEPNewt

Link to comment
Share on other sites

From the video I can confirm your choke and fast idle linkage is not working properly. It might be because the choke is not adjusted correctly, or it might be that your choke linkage is all gunked up.

Next time, take video of the "choke butterfly" on the the top of the carb while you operate the throttle.

Link to comment
Share on other sites

  • 9 years later...
On 10/8/2011 at 10:35 PM, 1965rivgs said:

As has been stated this is a common problem with any car that sits idle for a prolonged period of time. Jim`s advice is great and will no doubt cure the prolonged cranking issue but try the following first and see if it works for you..

It is true prolonged cranking can overheat the starter and add unnecessary wear and tear but a little cranking after an idle period is not all bad. I dont mind a few extra seconds of cranking as it gets the oil pressure building for initial startup.

First item to check is the accelerator pump in the carb. If the pump is not providing a good sustained shot of fuel this will not only cause excessive cranking on cold startup but a definite bog when accelerating hard even after the engine is warmed up.

After the engine is up to temp and the carb bowl is up to level take off the air cleaner and look down into the primary(front) side of the carb-engine off !!! Quickly open the throttle as if jamming the accel pedal to the floor and look for a healthy and sustained shot of fuel from the primary nozzles located in the upper air horn in the center. The nozzles project into each barrel from a central point which looks much like a battleship gun turret.

If there is no accel pump shot the carb needs work.

If the accel pump checks OK there is a method I use which can reduce cranking time.

Crank the engine for about 5 to 10 seconds. At this point most folks depress the pedal to the floor once or twice to set the choke but because there is a less than an ideal level of fuel in the bowl this does not provide enough raw gas in the manifold to initiate starting. Instead, try depressing the pedal 5 times or more. Although there is little fuel in the bowl and the accel pump shot volume is diminished, pumping the pedal excessively will usually result in enough fuel in the manifold to get started, or at least get the engine to turn over a few times and help fill the carb bowl. If the car tries to start and run but dies, pump the pedal 5 times again, remove your foot from the pedal so the choke is completely closed, and the engine will usually spring to life with enough fuel in the manifold to stay running.

Works for me. Also a good idea to keep a trickle charger on the car if sitting for a few weeks or longer to provide a healthy spark. Have fun,

Tom Mooney

Not to revive an old thread, but my 65 has recently developed this issue, and I tried your method just now, and it seemed to work. Good advice!

Link to comment
Share on other sites

I tried to open/down load the document referenced in this posting fro a decade ago by T J Thorson.

 

Posted October 11, 2011

The thread you referenced was mine, I went back and updated it.

http://forums.aaca.org/f177/troubleshooting-hard-starting-64-a-292435.html

 

and the system says it does not exist.

Is it gone or am I doing something wrong??

Link to comment
Share on other sites

1 hour ago, Craig Balzer said:

I tried to open/down load the document referenced in this posting fro a decade ago by T J Thorson.

 

Posted October 11, 2011

The thread you referenced was mine, I went back and updated it.

http://forums.aaca.org/f177/troubleshooting-hard-starting-64-a-292435.html

 

and the system says it does not exist.

Is it gone or am I doing something wrong??

Is this what you are looking for:

https://forums.aaca.org/topic/158968-troubleshooting-hard-starting-on-a-64/

 

  • Like 1
Link to comment
Share on other sites

Related to this thread, for those of you who are running an Edelbrock in place of an AFB or 4GC/Quadrajet and may not start your Riv for a couple weeks or more, pouring a small amount of gas from a small clean container into the forward barrels and then closing the choke butterfly either manually w/the linkage or one press of the accelerator pedal always does the trick, letting the starter crank a few times to circulate oil but reducing excessive cranking. Edelbrocks seem to be known for this. Mine is a 1406 on a stock '63 401. 

Link to comment
Share on other sites

Rather than pouring gas into the venturi, check to see if the bowls are low on fuel by adding fuel through the vent tubes.  Then use a normal starting procedure to see if things improve. 25 years ago, I was driving my 63 as a daily driver.  I had the choke set properly and the car would start right away every morning.  I noticed in the vert first pictured that was posted that the carburetor pictured is an aftermarket Carter AFB Competition Series carb, therefore, I'm assuming that it is either running an electric choke or has a hand choke.  If it is an electric choke, the instant that the key is turned on, the choke starts operating. If you're cranking for 45+ seconds, your choke is already partially open by the time you're finally getting gas in the fuel bowl of the carburetor.

 

On my 64, I have an electric choke on the OE 64 Carter AFB.  But the choke is wired to a oil pressure sending unit from an early 80s Buick Skyhawk ( I think I'm remembering correctly. It takes an adapter to fit into the nailhead block.)  The sender has three prongs on it rather than one.  One operates the oil pressure light as normal.  The other two work as a switch. 12V goes into one terminal and a wire to the electric choke goes to the other terminal.  The internal switch within the sender is open until the engine starts and oil pressure is obtained. As soon as the engine has oil pressure, that internal switch closes and 12V is sent to the choke. In other words, my choke is not activated until the engine is running rather than starting to work the instant 12V is switched on - that can be cranking time, fuel delivery time while the electric fuel pump is kicking in, or cranking the engine trying to start it.

  • Like 1
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...