Author Topic: "NEW" PROBLEM(S), PART 2:  (Read 8467 times)

Offline Stewart G Griffin

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #15 on: August 10, 2009, 11:25:30 PM »
1) Very good links;  Thanks.

2) The carb is a rebuilt unit, so there's really no need to overhaul it yet.

i'm thinking if cold, then one or two pumps and then release while cranking?

If warm then hold the pedal down halfway while cranking?

i should add that the engine did run quite good 3 yrs ago in this very truck (long, almost tragic story; pls see other posts) with this carb.

And then again a few days ago, again with this carb.   So were close.

i'm thinking there is not enough fuel in the carb or something.
« Last Edit: August 10, 2009, 11:30:37 PM by Stewart G Griffin »

Offline Marc

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #16 on: August 11, 2009, 09:41:07 AM »
Are the plug wires routed correctly and connected properly?  Is it backfiring?  You could also have a massive vacuum leak too.

Offline Stewart G Griffin

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #17 on: August 11, 2009, 09:50:30 AM »
i should have mentioned that the engine has run for a few secs, so the distributor is in phase and all the plug wires are routed correctly.  Whether the distributor is timed ideally is unknown at this point.

No, no backfiring.

i think we're ok as far as vacuum leaks as i've plugged the big hole in back for the power brake vacuum booster.

Offline Stewart G Griffin

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #18 on: August 11, 2009, 07:08:52 PM »
Next, i want to run a few scenarios past you:

1) If a carbed engine is cranked and cranked, but doesn't start (for whatever reason) would this flood the engine?

a) how do you know if an engine is flooded?

2) What's a reasonable fast idle speed?
a) in general?

b) For Rochester 2G's?

Offline Donut

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #19 on: August 11, 2009, 09:03:16 PM »
Ok, I'll try with my limited knowledge  :) (These are my opinions, not to be confused with that of a real mechanic)

1) It could, a)I usually pull the dipstick, if the oil reeks of gasoline, change it. Fresh plugs wouldn't hurt either (I've never had any luck getting wet plugs to fire consistently, even after they've "dried out")

2) Fast idle speeds I've usually done by ear. 1100-1200 +/- ?  I believe right now my Q-jet is @1000 for high idle, about 800 "kicked down" I'm working on it now, so that might change. (especially when colder weather moves in and I get my choke adjusted correctly)

b) for the 2g specifically ?

I didn't know the correct starting procedures for a Q-jet until I read them on my sun visor (*chuckle*)

As another disclaimer, I don't think I've touched a 2bbl in 15 yrs.  But all carburetors do basically the same job, meter the air and fuel.

Why I mentioned the rebuild kit earlier, let me tell you a story.  Last summer I bought the kit to rebuild my Q-jet.  The throttle shafts needed to be bushed, and the choke system was completely gone.  Went and bought a re-man unit.  Fired up the truck, couldn't adjust it, one side of the carb was running quite a bit richer than the other.  I tore the carb apart, one of the primary metering rod hangers was bent so more fuel was getting dumped on that side.  Bent it back down even with the other, double checked the float level (a little low, but not to bad) and rinsed out some crud that managed to be in there.  Set the idle mixture, then tried to drive it.  It would pull good for about 30 seconds then fall flat on it's face, like it was out of gas.  If I was at part throttle, I was fine.  Pulled the carb apart again, I thought the float or needle was sticking, i noticed the needle/seat assembly was smaller than what was in the kit.  Swapped them out and I was ok.  It seems like I keep going back to the rebuild kit for misc parts that I need (and the rebuild kit should have complete specs for the carb it's going in.)

I just changed the cam and heads.  Driving around (after break in) I had a flat spot about 2000 rpm, pulled carb apart again and it's got crud in it (earlier today)  I must have knocked some loose when I changed filters and the hard line.
'73 Chevy K-20 ***SOLD***
350/tbh350/np205
My plow was half price if i took the truck with it.

'86 C-30 dually, 454/tbh400

Offline Stewart G Griffin

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #20 on: August 13, 2009, 12:16:42 AM »
UPDATE:

i got it running normally.  i got fast idle to around 1000-1200 and normal idle around 800 and in gear 500-600.  i think it was just a case of the engine just needed to be run/turned over for a while to "shake the cobwebs out" so to speak.  It actually started to idle pretty smoothly after a few seconds of sputtering.

i took it for a short test drive and there is serious and immediately noticeable lack of torque and power as compared to the crate 350, but i don't really care---i'm just using this as transportation.

So, alas, i think we can finally close the chapter on this problem.

What did i/we learn this time?

a) don't give up.

b) i tend to get a little worked up/nervous/ emotional when it comes to car problems;  i need to stop thinking so hard and just get in there and do it.  i think this can apply to life in general as well.

i would sincerely and profusely like to thank anyone and everyone who tried to help me.

eventhorizon was always there for me, especially with the diagrams.

But really, thanks to everyone who helped.

Life is good again.........even if only briefly.

Offline eventhorizon66

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #21 on: August 13, 2009, 12:58:37 AM »
Glad to hear you've got your truck back on the road.  Did you end up keeping your 350 to rebuild someday?
'85 C10 SWB 350 700R4 TKO600

Offline Stewart G Griffin

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Re: "NEW" PROBLEM(S), PART 2:
« Reply #22 on: August 13, 2009, 09:40:53 AM »
Yes, i still have the crate 350.  It's my full intention to rebuild it.   i just don't know when because of time contraints.


Actually, i have a hunch that the short block doesn't even need a rebuild----i think one of the heads was warped or cracked causing one of the cylinders to fill with water and hydrolock causing the valve to break.


But we'll see.


P.S.  i also learned that i need to marry or live with a doctor or lawyer or investment banker ($$$)

and 2) the choke works just fine---opens up after about 2 mins.
« Last Edit: August 13, 2009, 11:16:25 AM by Stewart G Griffin »