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Old 05-28-2006, 12:42 AM   #1
Gray Ghost
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Dissy problem and a carb whistle?

On my 'new' CST, I have a quirk. Once it warms up, when I leave the stop signs, it feels like there's a bunch of tiny interruptions in the power...almost like it's cutting out a bunch of times. It feels electrical, so I have replaced the coil, cap, rotor, wires, plugs and all the vacuum lines, but the problem is still there. Could it be the internals of the dissy? Could it be fuel related as in the carb?

I also ran a tach to the dissy and the RPMS are not consistent with the problems. I think it's a bad tach cause it stays at 3k from 60-70mph, but I wanted to know what you guys thought before I removed it.

The other thing is weird...at hammer down time, the carb whistles very loudly at about 3500-4k on the tach. I have replaced all the vacuum caps and the lines....what could this be [stock Q-junk BTW}.

I am hopng I can find an answer to these q's, the motor feels like it could be a very sweet runner if these quirks were fixed.
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Old 05-28-2006, 01:03 AM   #2
Stocker
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Re: Dissy problem and a carb whistle?

Possibly a bad (upper) bushing in the dizzy -- letting the shaft wobble around a bit? No clue about the whistle, seems like a vacuum leak somewhere...
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Old 05-28-2006, 09:50 AM   #3
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Re: Dissy problem and a carb whistle?

That's what I thought...maybe the carb has a leak somewhere in the gaskets. I know it's not a vacuum line as I have replaced them all.
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Old 05-28-2006, 10:03 AM   #4
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Re: Dissy problem and a carb whistle?

Try to find the vacumn leak using a piece of hose. I use a left over piece of drain hose from installing my water softner. The hose is about four feet long. With the engine running, hold one end of the hose by your ear and move the other end around the intake and the carb. You will hear a whistle or sucking sound when you find the leak.
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Old 05-28-2006, 10:04 AM   #5
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Re: Dissy problem and a carb whistle?

have you cleaned and set the points?? have you changed the fuel filter in the carb?
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Old 05-28-2006, 10:08 AM   #6
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Re: Dissy problem and a carb whistle?

bad vaccuum advance maybe the cutting in and out at take off i had the same problem i changed the advance and its fixed dont know about the whistle
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Old 05-28-2006, 10:15 AM   #7
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Re: Dissy problem and a carb whistle?

Good idea Don! I will try that.

I have an external fuel fliter [new] and there's no advance hookup to the dissy...it pinged like mad when I first got it, so I am running no vacuum hose the advance, retimed and now premium gas to eliminate the pinging [it worked]. Could it still be cutting in and out even though it isn't hooked up?

I have an HEI, but I got a sneaky feelin' it's not a good one inside.
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Last edited by Gray Ghost; 05-28-2006 at 10:15 AM.
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Old 05-28-2006, 12:16 PM   #8
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Re: Dissy problem and a carb whistle?

The whistle would suggest vacume leak. did you plug off the hose you pulled from the vacume advance? That could be your whistle. Both a vacume leak or timing too advanced could cause all the pinging. Time it correctley and put the V/A back on. If the hose on the V/A was not the vacume leak then find out what was. A vacume leak can cause it to mis and sputter on take off. After you possitve there is no vacume leak and it still misses then look into electical problems

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Old 05-28-2006, 12:21 PM   #9
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Re: Dissy problem and a carb whistle?

Kelly, be sure you didnt have the dizzy hooked to full time vacuum. It should only "suck" under acceleration. I replaced the dizzy in the 68 because the advance was rusted and hard to move. Now it runs much better at take off. It also stopped using oil and fouling plugs. I added a second pcv at the same time so not sure what fixed the oil and plugs. It was fouling #8 about once a week and now the plugs are white and clean after many many miles.
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Old 05-28-2006, 12:34 PM   #10
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Re: Dissy problem and a carb whistle?

If it were me, I would pull the dist. and check it out and replace if needed, and then look at the carb., if the dist. wasn't it. Sounds like it might be the afformentioned bad bushing, worn gear, or something similar.

Jeg's or Summit both have HEI dist. for $125 and up. For the money I would get a whole new Dist. and know it was no longer a problem. The new one would also be capable of more RPM than the stocky anyway, for future use.

I'm also not a fan of Q-jets. I know alot of people that run them w/o problems. I just prefer Holley's 4150 platform. Thus I currently run a Street Avenger 670. It runs better than the Q-jet I replaced, so I don't consider it a waste of money.

I do have the q-jet I took off in the shop. You are only a town away from me (I'm in Kaufman). If you need to we could put it on your truck before you go buy something, just to see if that is the culprit. I would just give it to ya, but a buddy of mine has dibs on it already.



Let us know what you find,

Jay
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Old 05-28-2006, 04:46 PM   #11
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Exclamation Re: Dissy problem and a carb whistle?

Might check and see if your throttle shaft is worn out I thought mine was the dist. allso .Had a buddy come by and said the throttle shaft was worn out put a new carb on and sheeeebang.It is worth looking at any ways.
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Old 05-28-2006, 09:31 PM   #12
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Re: Dissy problem and a carb whistle?

Olden Days....Yep, the hose is gone and both ends are plugged. I couldn't get it to stop pinging until I plugged it off and retarded the timing a little more. I tried retarding the timing first, but it still pinged a bit. I've already come to the conclusion that there's no vacuum leak. I replaced ALL the vacuum lines and plugs. It is timed very nicely now and doesn't ping. I really suspect the dissy to be a bad one, everything looks pretty old inside except the new parts I replaced [cap, rotor, coil].

Jackie, I think it was in the right line...not sure. I think it will be replaced soon, but I had to try the other stuff first [easier].

Psycho, thanks for the offer...I am going to get an Edelbrock on here as soon as I pay some bills. I hate Q's as well. I've not tried the Avenger yet, but have heard good things about it.

Kaycee...it might be that for sure....I'll have to have someone else look at the carb if it isn't the distributor. I know nothing about Q's except that I hate 'em.
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