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Discussion Starter #1
I have a question for you fine gentlemen. I have a straight six 250, and the engine is running abit rough. Slow to accelerate, Rough idle that dies constantly. At highway speeds, I find myself needing to feather the throttle constantly, or keep it mashed to the floor. I just rebuilt the engine, and I have yet to get it to run correctly. I also installed an rv cam. The distributor points were changed out some time ago in favor of pertronics electronic ignition. I checked the timing and it is correct. What should I be running the base timing for the ignition at? My only other suspicion is the craptastic carb. I rebuilt that not too long ago. I am running out of ideas here, as well as hair. :sweat:
 

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If the timing seems to be in place (make sure that the harmonic balancer didn't slip, so VERIFY your TDC position), and check the carb again. Do the idle screws help to set the idle when you adjust them? Make sure you've got it running with the right mixture, and the right speed. 650~ in drive if it's an automatic, with your lights on bright. Make sure that the pertronix is working correctly. Check your points gap. Ford 250/6, right?
 

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Discussion Starter #3
No, the engine is chevy. I will check out the harmonic balancer. The idle speed is high, and the mixture is running on the rich side. I will double check my pertronix as well. I still have a set of points that I can throw in to double check.
The carb itself merely has a mixture screw. It's a one barrel rochester. I hope this helps.
 

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Irk2,

Check the float level in the carb. If the level is too low the engine guns lean when you step on the gas. By playing with the gas pedal while you are driving causes the accelerator pump in the carb to squirt a little fuel into the carb and the engine runs better.

There might be a vacuum leak also so check your vacuum readings. Both at idle and at around 2000 RPM.

Good Hunting
Scholman
 

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Straight six 250 Question

Yeah I runn a lott of , mechanically advanced Dizzy's in Vw's with Compu fire and Pertronix electronic ignition's .
Im Pullin Complete blank here with my Photographic Memory ? << Mean's I seem too be Unable , too Picture a 250 Chevy Dizzy ?
But Very Typically on Compu fire and Electronic Ignition install's On Vw's .
Guy's will remove the Condensor << Not needed for the Electronic ignition .
But they will remove the Condensor from side of the Dizzy . Then reinstall the screw Back intoo the Dizzy houseing , too plug the screw hole that held the condensor ontoo the side of the Dizzy .
On mechanically advanced Vw Dizzy's the screw goe's back in too the Distributor houseing deeper . Because it no longer hold's the condensor clipp and condensor on .
What happen's is the screw being screwed farther back intoo the dizzy houseing , it protrudes so deeply that either the counter weight's of the advanceing mechanism hit it , or it can interfere with the striker plate, advancement .
This interferes with the Advance of the distributor ?
Long story short ? >>. If you removed condensor from side of the Dizzy , Then used the screw that held it on too plug the, screw hole ? Try removeing the screw ! And or addin 2 or 3 Washers under the screw . So that it doesnt protrude too deeply inside the Distributor / aka dizzy houseing
Wich could interfere with the striker plate Advancement .
Sure sound's like , what Ive seen , with the Vw's <<, Common place with Vw's ! Impeded Vaccum or mechanical advance , Due too hittin Condensor screw , that has been turned, too deeply intoo Distributor , houseing ?
Just a thought ? bell's went off in my head . Readin this post !
If Vaccum advanced . Pull capp off Suck on the end of the Vaccum Hose . See if anything is impedeing or Blockin the striker plate advancement ?
Like Condensor screw etc.
Please lett me know if Im right here ? Im curious ?
Sean
 

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Discussion Starter #6
I see your fine points, Sean, and scholman. I think the real problem is my idle is too high to begin with. I am running a stock th 350 and I think the torque converter is stalling the engine out. I am not sure if there are any tricks to installing rv camshafts. If one has to set the timing off in order for the firing order to be correct? I doubt that is the case, but I can't help but wonder. Anywho, I appreciate everyone's advice. I will keep trying to find the solution.
Please feel free to keep this fine ideas coming my way! Oh, and to add more info. Vaccuum leaks have been checked for in the past using a smoke machine, everything seemed in order. However, the engine does have abit of an erratic shake going on. I swear, if GM had merely made everything reversed thread, I would never have to tighten a bolt ever again!
 

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Straight six 250 question

Yeah But Just pull the Screw Back out that was holdin the Condenser . << Might fix it . Might be the Advance mechanism is wedged against this screw ? Could cause High Idle . Coughin , gunk Gunkin when you accelerate ?

On 009 Dizzys For example . Compu fire say's too leave this screw out . What happens is the Mechanically Advanced Dizzy has Weights Inside the Distributor on Spring's << Centrigugal force Cause these Weight's too Spread out , under the striker plate << This is how the Distributor Advances itself .

If you Remove the Condensor Via a Screw . Then Use the screw, too plug the screw hole . << It goe's too deep intoo Distributor Houseing . The dizzy spinns >> Centrigugal force spread's the Advancement Counter weight's <<< These hit the end of the Screw inside the Distributor Retard's timming << Gunk Gunk , Sputter Sputter , Puke puke . Remove the Screw add 3 washers <<< 5 Minutes ?

On Instruction Sheet Came with the Pertronix <<, Look see what Small Print Say's . On Compu Fire Ign for 009 Dizzy's << There instruction's << In a Foot Note, say too leave screw out too prevent this ?

On 250 chevy << I have No idea . But I would surely take 5 seconds too look at it . Even pop Dizzy capp Off Pull Vaccum advance Hose , and Suck on it While Observeing the Striker Plate Movement isnt Binding on part of the Pertronix Ign Assembly or Screw's etc .

Lett me know Im kinda Curious if Im right, on this But I also Agree with Scholman . <, Be my next Course of Action . Badd Float or Float inlett Valve ETC.
Sean
 

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Discussion Starter #8
I checked to make sure that the screw was not interfering with the advancement of the distributor. I have vaccuum advance, and there is nothing interfering with it. I called the camshop today, and they gave me some advice for tuning the engine's ignition timing.
 

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Doc here, :pimp:

Did you check your Ignition Coil?

PRIMARY= Less than an ohm, but more than 000, out of that range toss it it's bad.

SECONDARY: 10,000 to 11,000 Ohms, outside of those ranges, toss it it's bad..



A Failing Coil can cause these symptoms also..the more stress you put on the coil, the less output it has under acceleration..

Doc :pimp:
 
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