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I have a 1963 Chevy II, 4-dr sedan, automatic with 194CI. Bought it in March 2017 with 21,400 miles, had the original bias ply tires and original brake pads.
Before picking it up I had a local Chevy dealership mechanic check it over and change fluids, replaced radiator, install new radial tires, install Pertronic ignition. I tried to prepare it for a drive.
After picking up the car and leaving town to drive to Tacoma WA, 50 miles out of town, stripped multiple teeth on the fiber timing gear. Then towed back to town.
3 days later with a new aluminum cam gear and steel crank gear installed headed back out of town towards Tacoma.
2300 miles later arrived in Tacoma. Added 1 quart of oil at that 2300 mile mark. I was very happy on the oil usage. But, the car didn't idle quite right but did OK on the highway
The car is now home. I rebuilt the carb, a single barrel Rochester, it did need it considerable crude in it. That helped on starting and the car now idles nicely if vacuum advance is unhooked and plugged. But the engine hesitates when giving fairly quick throttle and with vacuum advance hooked up I get a fairly even 'popping' from the exhaust. Idles better with no vacuum advance hooked in.

When timing, this engine times on #5 cylinder. This has me baffled and I'm wondering how or why it is this way. Using a vacuum gauge only to time, hooked at the base of the carb just above the intake manifold, I get 21" plus of very steady vacuum when idling. When I then use the timing light to check, the timing mark is right in the 6 to 12 degree BTDC range. So things seem to all be good. I currently have it timed at 7 BTDC.

BUT, why is this engine timing on #5 cylinder and I'm also not sure why I get hesitation when giving throttle? Something to do with the new timing gears?
Maybe two different issues, maybe not. That is why I am reaching out, to see if someone might know.
Thanks for any help that you may be able to provide.
 

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I'm gonna throw out a guess... spun balancer? Firing order is 1-5-3-6-2-4, so when the timing mark on balancer lines up with 0 on timing tab, #1 should be at TDC. Pull #1 plug, stick a screwdriver in hole, rotate until you feel the piston stop rising. Timing marks should line up. If yes, your distributor is set wrong.Verify compression stroke before moving distributor. If no, timing marks are not stock or have been messed with. Balancer may have spun due to bad rubber strip.
If marks line up & it runs poorly timed off #1, I would pull timing cover off & make sure sprockets line up.
Anybody have better idea?
 

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67 4 door, 65 wagon (in pieces)
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Is the hesitation only from a stop or does it bog when you're cruising and give it more power? If its just from a stop, your idle needs proper adjustment.


From here:
http://www.thecarburetorshop.com/Troubleshooting.htm#Acceleratorpumps


Bog from a stop is virtually always (and generally erroneously) diagnosed as a faulty accelerator pump (see the section on “accelerator pumps” for testing). Most modern carburetors are designed to function with roughly 0.020 (20 thousanths) clearance between the center of the throttle plate edge, and the throttle body at a point equidistant from the throttle shaft bearing areas. This clearance allows for maximum velocity of idle air past the idle ports. Exceptions to this are GM carburetors with the idle speed air screw, and end carburetors on tripower. Setting the idle for the highest vacuum idle reading will result in too little clearance of the throttle plate; forcing too much of the idle mixture through the lower idle port and too little through the idle transfer slot. This will cause a phenomena called “puddling” where little droplets of gasoline adhere to the intake manifold runners. When the throttle is opened, there is now sufficient velocity of air to sweep all these droplets into the cylinders, creating a mixture which is too rich to burn, hence the bog. As soon as the overrich mixture is pumped out the tailpipe, and a normal mixture is ingested by the cylinders, the bog disappears. A defective advance mechanism can also cause bog; as can a defective accelerator pump. If bog exists only from an idle, not when accelerating from a constant speed, the idle adjustment is probably the culprit.
 

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Discussion Starter #4
I'm gonna throw out a guess... spun balancer? Firing order is 1-5-3-6-2-4, so when the timing mark on balancer lines up with 0 on timing tab, #1 should be at TDC. Pull #1 plug, stick a screwdriver in hole, rotate until you feel the piston stop rising. Timing marks should line up. If yes, your distributor is set wrong.Verify compression stroke before moving distributor. If no, timing marks are not stock or have been messed with. Balancer may have spun due to bad rubber strip.
If marks line up & it runs poorly timed off #1, I would pull timing cover off & make sure sprockets line up.
Anybody have better idea?
I'm looking into getting a new timing pulley/balancer. I'm going to look at mine tonight and see if i can tell if just a simple metal pulley or if rubber in there. Or is there always rubber, then the possibility to spin some.
If it did spin, it spun perfectly to time on #5. Timing with vacuum only puts it right in the timing marks range.
One of the first things that I did was to feel #1. I used 1/4" rubber hose. #1 was no where near top when the timing mark was on Zero.
The 'marks' on the cam and crank timing gears do line up. I have a picture of those when the new alum-metal gears were installed after the original fiber cam gear stripped some teeth.
My current truck is the first vehicle that I've had that doesn't require timing. And, I've never had to use anything other than #1 to time all. Apparently no spinning of any of those balancers.
So, #5 has me baffled.
Thanks,
Jim
 

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Discussion Starter #5
Is the hesitation only from a stop or does it bog when you're cruising and give it more power? If its just from a stop, your idle needs proper adjustment.


From here:
http://www.thecarburetorshop.com/Troubleshooting.htm#Acceleratorpumps
Right now, the hesitation is just when I give it a little quick throttle when tuning. I just rebuilt the carb. Got a kit from Mike's Carb in WA. The carb was very dirty inside so needed it.
I cleaned all with carb cleaner and blew out all of the ports and holes that I could see. I put in a new needle and seat and a new cup on the accelerator pump. As far as I remember I only saw 1 hole out of the bottom of the pump well. It had a ball and spring, cleaned that.
Should I have smoothed or taken more care on the well sides where the cup actually seals and seats?? Maybe it's not pushing enough gas.
The car has always cruised fine on the highway. If I step on it when driving, I can always knock the auto trans down into first.
We still have snow and mud here, so I'll wait till better conditions before taking out on the road.
Maybe then decide if I need to take the carb apart again.
Thanks,
Jim
 

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Discussion Starter #7
is the vacuum adv holding vacuum?
they can go bad
When I have the vac advance hooked up and check the timing with the light at idle the timing is well advanced and off the scale. I'd say advanced to 25 or 30 degrees or so. Too much advanced??
With no advance hooked up the engine idles perfectly smooth at 650rpm or so.

I've currently got the idle set at 475rpm when the auto trans is in 'drive' and the advance hooked up.
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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Jim

( I'm thinking your idle rpm's might be a little low side (even in gear) ..... Then when you press the throttle your carb ' has too kinda catch-up -- thus, the bog.
I'm way over in 'Sunny Arizona' -- hard to hear it run ....... just pulling-u'r-leg ...

check u'r pm's

...... jim
 

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Discussion Starter #9
Jim

( I'm thinking your idle rpm's might be a little low side (even in gear) ..... Then when you press the throttle your carb ' has too kinda catch-up -- thus, the bog.
I'm way over in 'Sunny Arizona' -- hard to hear it run ....... just pulling-u'r-leg ...

check u'r pm's

...... jim
The specs that I have say set at 500rpm when in drive. When not in drive the rpm's seemed a bit high so I knocked it down 25.
This weekend I drove the car and see that I also get the hesitation at 55mph when stepping on the gas??
Carb or timing? Until i get a new balancer on I may not know.
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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My 2cents ------------------------

THE 1bbl CARB ........ some of them were not too great even back in '63. Meaning, you ARE - NOT going to find any great 'Rochester 1bbl 's'
tooo often.

I had a good one on my 250 for 12 - 15 years (I do not have that carb any-more ...... long-gone, now).

My 1st 1bbl carb - I did rebuild it , and it worked good ....... but cracked the housing (where the fuel line attaches) leaked onto my exh manifold -- not a good thing).
That's when I found my 'Good Rochester' , and ran that forever.

Bottom line ... Keep Looking for other 1bbl carbs ... most leak around the top section. Tweek your timing for best running (your timing is very close , just adjust for that "sweet-spot --- or as best you can" .

look for any/all 1bbl carbs ........ don't limit yourself too just (63 Nova) ....... for example : there should be a million Chevy trucks w/six cyl (with the later type engines -- 194 - 230- 250 type motors ------- not the 235's). And, look for the least smog - type - carb .

(((( as an example : I had a VW bug w/DP engine - single 'Solex carb' .... I hated that carb .... at work, we were converting all our company trucks over too Propane systems.
Thus, we had a Shed Full of New 'Ford 300 six (Motorcraft) 1bbl carbs ----------- guess which carb I installed on my bug ..... fairly easy, and ran great too )))

later , jim
 

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Discussion Starter #11
My 2cents ------------------------

THE 1bbl CARB ........ some of them were not too great even back in '63. Meaning, you ARE - NOT going to find any great 'Rochester 1bbl 's'
tooo often.

I had a good one on my 250 for 12 - 15 years (I do not have that carb any-more ...... long-gone, now).

My 1st 1bbl carb - I did rebuild it , and it worked good ....... but cracked the housing (where the fuel line attaches) leaked onto my exh manifold -- not a good thing).
That's when I found my 'Good Rochester' , and ran that forever.

Bottom line ... Keep Looking for other 1bbl carbs ... most leak around the top section. Tweek your timing for best running (your timing is very close , just adjust for that "sweet-spot --- or as best you can" .

look for any/all 1bbl carbs ........ don't limit yourself too just (63 Nova) ....... for example : there should be a million Chevy trucks w/six cyl (with the later type engines -- 194 - 230- 250 type motors ------- not the 235's). And, look for the least smog - type - carb .

(((( as an example : I had a VW bug w/DP engine - single 'Solex carb' .... I hated that carb .... at work, we were converting all our company trucks over too Propane systems.
Thus, we had a Shed Full of New 'Ford 300 six (Motorcraft) 1bbl carbs ----------- guess which carb I installed on my bug ..... fairly easy, and ran great too )))

later , jim
I will take it on the road and try that and see if I find a sweet spot.
Jim
 

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I'm gonna throw out a guess... spun balancer? Firing order is 1-5-3-6-2-4, so when the timing mark on balancer lines up with 0 on timing tab, #1 should be at TDC. Pull #1 plug, stick a screwdriver in hole, rotate until you feel the piston stop rising. Timing marks should line up. If yes, your distributor is set wrong.Verify compression stroke before moving distributor. If no, timing marks are not stock or have been messed with. Balancer may have spun due to bad rubber strip.
If marks line up & it runs poorly timed off #1, I would pull timing cover off & make sure sprockets line up.
Anybody have better idea?
Good advise. Also when you have #1 piston at TDC (make sure it's on the compression stroke) make a mark or chalk line on the dampener at 0* on the indicator tab. You can then use this mark to set the timing on #1 cylinder. IMO getting the timing close may help out your carb issues.
 
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