older pcm 351's question

[dshaff24]

Seriouslly.. my motor is in great shape.. its just so cold hearted.. Once warm she's perfect but bumping it in and out of gear when cold she just wants to idle down and shut off! With or with out the Choke properly working.. If I start it and let it idle for a 40-50 seconds its goes right into gear and idles on out! And im not talking COLD.. im talking running it all day then sitting for an 30 minute to an hour.. the temp of the motor is around 100 degrees and it fires right up.. I have to idle it up for a few seconds and then see what happens..

This is really my only complaint on this boat.. my dad keeps telling me to rebuild the carb since its original but It runs so great when warm.. that Im having a hard time justifying it!


WHAT is your process when starting your old 351W? I get in it pump the throttle twice and she fires right up..cold or hot

IF yours sits after running a while do you have to pump it 2 times then fire it up? Do you let it IDLE high for a couple seconds then put it in gear to pull out? Or am I just crazy?

The Choke was causing me to flood the motor in the summer so I decided to remove it..

Just checking to see if im crazy.. my dads old dump truck has a 360 ford and new carb and its colllldd coolldd hearted to.. runs great once warm!

[DAFF]

Seems to me the carb is getting ready for a rebuild. Or the choke is not working / set properly. Cold start double pump an the trottle and turn the key.... Engine should start with a high idle. As the electricial system powers the choke it should lower the idle and reduce the amount of fuel into the carb.

Since you have removed the choke I would put 95% of the cold start issues in this department, get it rebuilt and have it set up by someone who knows carbs. As for your dads dump truck it too needs the choke to be set up.

[cadunkle]

You removed the choke and are wondering why it doesn't run great right after a cold start? You answered your own question.

When you had the choke on the carb it was not adjusted properly if you get getting flooding issues on hot starts. My advice is to rebuild the carb, since it has never been rebuilt, and put the choke back on.

It can take a few days of using the boat and cold/warm starts to get the choke dialed in perfect. Also, there are 3 aspects to adjusting a Holley electric choke. Twisting the large choke knob adjsuts the duration of the choke... How long before it is fully open. Bending the linkage to the choke butterfly adjusts how open/closed the choke is at cold start. Adjusting the high idle screw adjusts the high idle throttle opening. All of these must be adjusted together to get a perfect cold start. There's no reason from stone cold you shouldn't be able to fire it up and drive away after 5-10 seconds (though I advise you stay at idle or off idle until your oil gets up to temp).

If you need more details on how to adjust the choke let me know and I'll give some tips.

[michael hunter]

Cadunkle is spot on with his post. I would rebuild the carb and reset the choke. On cold start do you pull the button to disengage the trans? Then raise the rpms to stabilize the engine for 30 sec or so before engaging the trans.

[jsandy]

choke for sure. knock on wood my boat fires right up and purrs like a kitten as soon as i look at the key.

[dshaff24]

Cadunkle is spot on with his post. I would rebuild the carb and reset the choke. On cold start do you pull the button to disengage the trans? Then raise the rpms to stabilize the engine for 30 sec or so before engaging the trans.

Yeah I take it out of gear.. pump it twice and she fires right up.. My problem is I have to bump the Rpm's up to about 1000 rpm till she is warm.. Then put it in Neutral to idle then bump in it gear

IF I just pump it twice and fire it up.. She will idle for a few then shut off Especially with the choke on it!

[dshaff24]

You removed the choke and are wondering why it doesn't run great right after a cold start? You answered your own question.

When you had the choke on the carb it was not adjusted properly if you get getting flooding issues on hot starts. My advice is to rebuild the carb, since it has never been rebuilt, and put the choke back on.

It can take a few days of using the boat and cold/warm starts to get the choke dialed in perfect. Also, there are 3 aspects to adjusting a Holley electric choke. Twisting the large choke knob adjsuts the duration of the choke... How long before it is fully open. Bending the linkage to the choke butterfly adjusts how open/closed the choke is at cold start. Adjusting the high idle screw adjusts the high idle throttle opening. All of these must be adjusted together to get a perfect cold start. There's no reason from stone cold you shouldn't be able to fire it up and drive away after 5-10 seconds (though I advise you stay at idle or off idle until your oil gets up to temp).

If you need more details on how to adjust the choke let me know and I'll give some tips.

Ive never really adjusted a carb before so my knowledge is very limited on it.. I did read alot on how to adjust it and I tried numous things before It just got to the point that IT runs much better with out it..

I was having issues with it while getting pulled that if someone would shut the boat off for say.. 3 minutes.. that it fire right up.. but when they would go to pull out it would shut off! Sounds like it would Load up with fuel but the choke wouldn't even be closed! Since I just removed it for the time being this problem went away!

[dshaff24]

So out of all the 351's on here.. You guys honestly just get in the boat pump it twice and put the lever back in Neutral? after say 30 seconds of IDLE time.. you pull out and your good to go? I shouldn't have to hold the throttal open a little to bump the rpm's? up any?

IF its really not a cold hearted motor then im going to dig into some of my options to get this minor issue figured out

[haugy]

So out of all the 351's on here.. You guys honestly just get in the boat pump it twice and put the lever back in Neutral? after say 30 seconds of IDLE time.. you pull out and your good to go? I shouldn't have to hold the throttal open a little to bump the rpm's? up any?

IF its really not a cold hearted motor then im going to dig into some of my options to get this minor issue figured out

Yes. I could get in mine, fire it up, and put it in gear. When it was the very first run of the day, I would back the trailer into the water. Wife would start the boat, and let it run at about 1200rpm while I unhooked. I got back in the truck and backed down enough to let the boat glide off. Then she would put it in gear and pull to the dock.

That is about the only "warm up" time we had. Any other time I would fire it right up, and go.

Rebuild your carb, and reset your choke. It will be night and day difference when done properly.

[cadunkle]

Yep, there is no such thing as a cold hearted or cold blooded engine in this respect. These are things people say to justify theirs not being properly adjusted or in need of a rebuild. The only time anything like that may apply is on high compression engines with a LOT of cam duration and overlap. That's a completely different animal though and most of those guys don't run chokes as they serve little purpose in those applications.

While the choke is still on you won't get the same performance and WOT will be slower than when warm. This is due to the choke butterfly restricting air into the primary side and the overly rich mixture. You should have no problem with the engine having reasonable manners at idle and off idle through lower RPM cruising on plane while the choke is still on. You will feel a definite improvement in power and responsiveness once warmed up though.

[supra wacko]

You also can check if the small gasket left under the choke is open sometimes this is full of crap. this gasket wil suck air into the carb. If this is not the issue rebuild the carb it take app. 3 hours and you're done for several years and the costs are not that high.

PLEASE CAN SOMEONE get rid of the person "bannybunlam" this person is ruining this forum with his mess.(thanx some already has been taking care of it)

Greetzzz

[rludtke]

For my first start of the day, I pump the accelerator a couple of times, and crank with the throttl slightly opened. I let her run for several minutes manually controlled to about 1200 rpm. Once she is ready to idle on her own, she is good to go for the rest of the day. My choke is not working correctly, I don't have 12 volts availible anymore (and I haven't bothered to troubleshoot it). Every start after the warm up is accompished with the throttle closed, she starts immediatly at idle.

I prefer to stay on the trailer until my engine temp reaches 160 before I back off.

I agree with the carb overhaul. These carbs are sensitive to the smallest amount of particulate buildup in the system, which can cause lots of different carb issues.

Holley's website http://holley.com/has lots of information about how to overhaul, and how to adjust. Its really very simple, and vary inexpensive. It probably should be done every several years or so.

Holley 4160 Information page: http://holley.com/0-80319-1.asp This link offers links to the Holley Renew kit, and technical information.