diesels

[Jims86]

all the things mentioned probably all play a role in the dieseling.

While factory specs are a good starting point, most of us do not even have "factory" stuff left on our trucks.

1. fix the choke...then see if prob fixed.
2. fire it up and place your hands over the openings in the carb... if it continues to run, you have a vacuum leak that is allowing it to get air to continue to run...then check to see if prob fixed after finding leak.
3. get the timing right, between 8-12 degrees BTDC is good for most SBC...Make sure you cap off all open ports and plug the timing advance line. then check if prob fixed.
4. fire it up and let it warm, then shut it off. If fixed then celebrate. If not, you need to tune the carb.
5. Set the idle screw to give you around 700-750 idle in PARK. Start with initial vacuum reading. You said you have a healthy cam so do NOT expect a high reading, anything above 12 Hg is good for you. I see you're in WV, I am happy with the 14 Hg I get here in the high elevation of NC and unless you're higher than me, shoot for 12 Hg or more.
Tune each mixture screw, turning the same amount on both sides. Tune to highest vacuum possible. After that turn idle screw back down to 700-750 rpm in park. Check your vacuum again.
6. fire it up and check for problem. Celebrate if fixed.

Make sure timing is checed and set in gear, at 500-550 to keep the weights from advancing, any timing higher than 6* is too much for a base line setting. most were 4 to 6 from the factory.

 

[Boone83K10]

yeah my sticker says 4 degrees. My engine won't even crank at that setting. I can't go by the sticker since my motor is built and swapped. That's why I mentioned that most of these trucks aren't even stock anymore and you can't really go by the sticker anymore.


but yes do it in gear, I agree to that. Mine is at around 600 in gear and goes to 750ish in park.

 

[HotRodPC]

it also stalled out while pulling the mountain yesterday then as soon az I let off throttle ot regained itself

Probably plugging up fuel filter.

If the hill had anything to do with it, could be a bad float adjustment in the carb too.

 

[Jims86]

yeah my sticker says 4 degrees. My engine won't even crank at that setting. I can't go by the sticker since my motor is built and swapped. That's why I mentioned that most of these trucks aren't even stock anymore and you can't really go by the sticker anymore.


but yes do it in gear, I agree to that. Mine is at around 600 in gear and goes to 750ish in park.

Yep...just assuming his is stock or oem replacement.

 

[WVscottsdale]

gonna try to set it tonite after work. engine is no where near stock. bored .040 over 11:1 pistons 480-490 cam 520 duration 650 holley dp edelbrock perfomer headers msd off road 6 ign box th350 trans

 

[Jims86]

gonna try to set it tonite after work. engine is no where near stock. bored .040 over 11:1 pistons 480-490 cam 520 duration 650 holley dp edelbrock perfomer headers msd off road 6 ign box th350 trans

Uh oh.....MSD.

 

[WVscottsdale]

I know what your thinking. the diode I didnt get one with it or that I remember but it has never done it before

 

[HotRodPC]

Now what about this cam? Is it 480 and 490 lift? What is the Duration? I know it's not no 520.

 

[WVscottsdale]

yeah lift 480 490 yeah duration is way off 230 intake and 236 exhaust. sorry bout that

 

[WVscottsdale]

intake lift 480 exhaust 490 and duration 230 & 236

 

[HotRodPC]

Ahhh OK. That's not a big cam. You'll be fine with a 600 Vac Secondary Carb with that. I worry about about the 11:1 compression though. I have a sneaky feeling you're having a detonation problem running your cylinder temp up real high and that could very well be the reason you're having the run on (dieseling) problem. Is your motor loud? As in, do you have headers and Flowmasters? Would you be able to hear pinging or detonation over the exhaust?

Also, are you sure you're at 11:1 compression? I ask cuz many times a guy will say, I've got 11:1 comrpession, cuz he has 11:1 (ADVERTISED) pistons. Well yeah, maybe they're 11:1 with a 64cc head and a thin metal head gasket, but with a comp gasket and 76cc heads, you're nowhere near 11:1. More like 9:1.

 

[WVscottsdale]

Ahhh OK. That's not a big cam. You'll be fine with a 600 Vac Secondary Carb with that. I worry about about the 11:1 compression though. I have a sneaky feeling you're having a detonation problem running your cylinder temp up real high and that could very well be the reason you're having the run on (dieseling) problem. Is your motor loud? As in, do you have headers and Flowmasters? Would you be able to hear pinging or detonation over the exhaust?

Also, are you sure you're at 11:1 compression? I ask cuz many times a guy will say, I've got 11:1 comrpession, cuz he has 11:1 (ADVERTISED) pistons. Well yeah, maybe they're 11:1 with a 64cc head and a thin metal head gasket, but with a comp gasket and 76cc heads, you're nowhere near 11:1. More like 9:1.

The pistons are 11:1 and the heads or 64 or 68 cc it's been a while since I built the motor. Yeah I have headers and 3 inch exhaust with flowmasters so I don't hear any pinging. But right now I have 87 octane gas. May have to step it up. Hell I had to pull the cam card to find the duration. Also a while back I had a parts guy get me the wrong spark plugs and and they where hotter plugs and it would diesel then so I got the normal plugs and it stopped. But it has done it a couple times since. Didn't get time tonite tune the motor tonite. Hopefully this weekend I will get a chance. I did get a chance to clean and lube the choke rod in the carb and reset the air fuel screws to the "starting" point 1 1/4 turns out, but that's as far as I got and they where out about 1 1/2 or a little more out. So with the issues and how I had to tune the carb before with strain of the trans to get it to idle straight. I am hoping that after a good tune the rich and diesel problem will go away and celebrate lol

 

[Driver4r]

The pistons are 11:1 and the heads or 64 or 68 cc it's been a while since I built the motor. Yeah I have headers and 3 inch exhaust with flowmasters so I don't hear any pinging. But right now I have 87 octane gas. May have to step it up. Hell I had to pull the cam card to find the duration. Also a while back I had a parts guy get me the wrong spark plugs and and they where hotter plugs and it would diesel then so I got the normal plugs and it stopped. But it has done it a couple times since. Didn't get time tonite tune the motor tonite. Hopefully this weekend I will get a chance. I did get a chance to clean and lube the choke rod in the carb and reset the air fuel screws to the "starting" point 1 1/4 turns out, but that's as far as I got and they where out about 1 1/2 or a little more out. So with the issues and how I had to tune the carb before with strain of the trans to get it to idle straight. I am hoping that after a good tune the rich and diesel problem will go away and celebrate lol

How the **** are you running 11:1 on 87octane????????\

I had to advance my cam 4deg. to get my 10:1 to run on 89. And even then, she still doesnt like it.

 

[HotRodPC]

WTH dammit? I know I typed up a post after this, and it's not here now. Not typing all that again, In short I was saying I ran .505 lift 310 duration cams, and a .525 lift cam 3?? duration cam in 11:1 motors and ran 93 Leaded with no problems, but it sure ran good on Trick Racing Fuel. This is due to having a big cam with plenty of valve overlap that leaked compession so I probably netted 9.5 - 10:1.

You could bleed off some of your compression by going with a bigger cam too. IIRC, the cam I was running and still ran a single valve spring was a .485 lift 280 duration on a 10.5:1 motor and it also ran 93 Leaded without problems. If compression does end up being your problem, do a cam swap to bring it down to a pump gas compression ratio and enjoy the extra power.

 

[WVscottsdale]

gonna run some octane booster in it then run thru this tank of gas. then try t he high test fuel after I thimk about it there may be some pinging under a strong load 3/4 to full throttle but with other rattles at the same time. I just need to tune and time the engine and go from there.