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-   -   Edelbrock Carb Help (https://67-72chevytrucks.com/vboard/showthread.php?t=602075)

rs74 11-14-2013 10:15 PM

Re: Edelbrock Carb Help
 
Man, I hate to hear you are having such a hard time. Getting everything timed right can be a real pain in the arse sometimes.

77ChevySharkBite 11-14-2013 10:17 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by rs74 (Post 6364342)
Man, I hate to hear you are having such a hard time. Getting everything timed right can be a real pain in the arse sometimes.

It has presented quite the challenge I won't lie but hey i'm learning and I know I'm getting close so its all good when its good and running it will all be worth it :metal:

rs74 11-14-2013 10:30 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by 77ChevySharkBite (Post 6364348)
It has presented quite the challenge I won't lie but hey i'm learning and I know I'm getting close so its all good when its good and running it will all be worth it :metal:

Good attitude to have! Hands on experience is the best.

77ChevySharkBite 11-14-2013 10:41 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by rs74 (Post 6364367)
Good attitude to have! Hands on experience is the best.

Yeah and don't get me wrong this has been disheartening but I know when it's running strong and better than ever it'll make all that annoying cussin, frustration, and drinking fully worth it.

bnoon 11-15-2013 09:38 AM

Re: Edelbrock Carb Help
 
I think you're chasing your tail by throwing parts at it. You set the timing and verified TDC physically (and I assume the balancer timing mark lined up when you did that?!?!), that would be the end of that road for me. A new balancer isn't going to solve anything if the mark lines up with a verified TDC and a verified #1 on the dizzy. I'm still stuck on the poor start up issue and kicking off of high idle too soon, to me, points to a simple choke setup problem, especially since you said it runs well with good power the rest of the time.

77ChevySharkBite 11-15-2013 09:43 AM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by bnoon (Post 6365431)
I think you're chasing your tail by throwing parts at it. You set the timing and verified TDC physically (and I assume the balancer timing mark lined up when you did that?!?!), that would be the end of that road for me. A new balancer isn't going to solve anything if the mark lines up with a verified TDC and a verified #1 on the dizzy. I'm still stuck on the poor start up issue and kicking off of high idle too soon, to me, points to a simple choke setup problem, especially since you said it runs well with good power the rest of the time.

Typically I would agree with you, but when we try to time it at 8 degrees advance the truck doesn't like it and if we would rev it in park it just would backfire so I can imagine trying to driving it like that would be worse as well. It's as if it's too advance, the truck has jumped time completely to the point where it wouldn't start so right now after verifying it again, I would be be betting it's my balancer to me that's the only thing I can think of to be causing all of this due to a timing issue.

martin_81 11-15-2013 10:51 AM

Re: Edelbrock Carb Help
 
i have a similar issue. it runs like a champ dont get me wrong, just that every here and there the idle seems to go low, and my oil pressure would drop. i will accelerate and it will slug a bit. i checked everything. everything was good till i finally came to conclude it was the carb. i clean it a bit not to much and felt a difference, but it will need its rebuild

77ChevySharkBite 11-15-2013 10:55 AM

Re: Edelbrock Carb Help
 
I'm not saying it's not possible but my carb is brand new hardly any run time on it or anything on it.

I'm lead to believe it's my balancer because the PO put his own marks on the balancer for what reason I have no idea the trucks motor was retarded so much that it ran the way it did. So I partially blame them on there timing and them improvising it so I'm thinking it's the balancer in which I have replaced but not yet installed.

chebyshortbox65 11-15-2013 11:29 AM

Re: Edelbrock Carb Help
 
So with everyone chasing their tail and keep going round and round no one seems to remember there is multiple diffrent balancers and timing pointer depending on the year of the engine later years should have had the timing mark straight behind the water pump earlier had the pointer at the left side @ a 45 degree angle so the po probably put a dont get you home chrome timing chain cover with the aftermarket timing tab and then re marked the balancer either change the balancer and timing tab to match which would have been easier when the chain was done you could have used those timing marks to be 100% you were on or do what everyother got rodder or real mechanic would do and set the timing until it runs good with no starting issues or detonation and e done with it

77ChevySharkBite 11-15-2013 11:33 AM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by chebyshortbox65 (Post 6365588)
So with everyone chasing their tail and keep going round and round no one seems to remember there is multiple diffrent balancers and timing pointer depending on the year of the engine later years should have had the timing mark straight behind the water pump earlier had the pointer at the left side @ a 45 degree angle so the po probably put a dont get you home chrome timing chain cover with the aftermarket timing tab and then re marked the balancer either change the balancer and timing tab to match which would have been easier when the chain was done you could have used those timing marks to be 100% you were on or do what everyother got rodder or real mechanic would do and set the timing until it runs good with no starting issues or detonation and e done with it

Actually believe this or not, it's still the original timing cover with the point at a 45 degree angle, so I personally though I don't have a lot of knowledge on how these engines work I think he just marked it not knowing where the original mark was and slapped it on and it ran "fine" so that's where they left it.

77ChevySharkBite 11-18-2013 11:13 AM

Re: Edelbrock Carb Help
 
Okay, so I got the truck back together and running so I took 3 videos

1st video is at 8 degrees advance, tell me I know it might be hard but do y'all hear anything that would make you think it's not running how it should and since I'm not driving I'm just doing power braking.


2nd video is at 0 degrees timing, which I can only tell 2 differences that it idles higher and that it idles smoother.


3rd video is just showing that I'm giving it good throttle, and in this video it's at 8 degrees advanced.


bnoon 11-18-2013 04:49 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by 77ChevySharkBite (Post 6365441)
Typically I would agree with you, but when we try to time it at 8 degrees advance the truck doesn't like it and if we would rev it in park it just would backfire so I can imagine trying to driving it like that would be worse as well. It's as if it's too advance, the truck has jumped time completely to the point where it wouldn't start so right now after verifying it again, I would be be betting it's my balancer to me that's the only thing I can think of to be causing all of this due to a timing issue.

You said you physically verified both the crank and the distributor at TDC. If that statement is true then there is no way a new balancer is going to fix your issue. You also stated that you verified that the rotor was pointing to #1 at TDC. The only way physically that crank to distributor timing could still be off is the timing set is either stretched out very badly or installed incorrectly.

STOP THE PRESSES!!! Take a picture of your distributor at 0* then again at 8* advanced. I would SWEAR that in the "advanced" video you're distributor is retarded and not advanced from the 0* shot.

77ChevySharkBite 11-18-2013 05:05 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by bnoon (Post 6370740)
You said you physically verified both the crank and the distributor at TDC. If that statement is true then there is no way a new balancer is going to fix your issue. You also stated that you verified that the rotor was pointing to #1 at TDC. The only way physically that crank to distributor timing could still be off is the timing set is either stretched out very badly or installed incorrectly.

STOP THE PRESSES!!! Take a picture of your distributor at 0* then again at 8* advanced. I would SWEAR that in the "advanced" video you're distributor is retarded and not advanced from the 0* shot.

Well do correct me if I'm wrong but the timing set is supposed to be at 12 on both the cam gear and crank sprocket? If that is correct that's how there lined up correctly.

Okay, so your saying that in my video where I'm supposedly advance it's possibly actually being retarded?

bnoon 11-18-2013 05:27 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by 77ChevySharkBite (Post 6370756)
Well do correct me if I'm wrong but the timing set is supposed to be at 12 on both the cam gear and crank sprocket? If that is correct that's how there lined up correctly.

Okay, so your saying that in my video where I'm supposedly advance it's possibly actually being retarded?

The timing chain gear dots will line up at 12/12, but typically you want to set initial physical timing with the cam at 6 and the crank at 12 since it's easier to tell if it's a tooth off.

From the video (it's quick and I can't tell for sure) but yes, it looks like you're retarding it instead of advancing it. Advanced is counter-clockwise and it looks like you went clockwise in reference to the 0* video. I could be wrong, but from the quick glimpse it looks like it.

77ChevySharkBite 11-18-2013 05:30 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by bnoon (Post 6370781)
The timing chain gear dots will line up at 12/12, but typically you want to set initial physical timing with the cam at 6 and the crank at 12 since it's easier to tell if it's a tooth off.

From the video (it's quick and I can't tell for sure) but yes, it looks like you're retarding it instead of advancing it. Advanced is counter-clockwise and it looks like you went clockwise in reference to the 0* video. I could be wrong, but from the quick glimpse it looks like it.

Okay. Well I placed it at 12/12.

That's exactly what it's doing when we would advance it the idle would drop, but when we would retard it, it would rise. So what would be my course of action? Would I take out the dizzy and try to figure out how many tooths it's off and just play with it that way or what?

bnoon 11-18-2013 05:46 PM

Re: Edelbrock Carb Help
 
So, were you advancing or retarding??? Set it at 8* advanced and adjust the idle settings on the carb.

bnoon 11-18-2013 05:50 PM

Re: Edelbrock Carb Help
 
And you understand how 12/12 timing marks could be harder to know if you're one tooth off... at 6/12 the tooth tips should be pointing towards each other directly.

77ChevySharkBite 11-18-2013 05:55 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by bnoon (Post 6370813)
So, were you advancing or retarding??? Set it at 8* advanced and adjust the idle settings on the carb.

Quote:

Originally Posted by bnoon (Post 6370818)
And you understand how 12/12 timing marks could be harder to know if you're one tooth off... at 6/12 the tooth tips should be pointing towards each other directly.

I was advancing it to 8 in the 1st video but I didn't ever think of adjusting the idle screws. Would I also adjust the high idle on it too? But when it was at 8* advance it sounded like it took half a crank then it would start where would I look at for that issue? Or would that be a choke issue?

Yes I understand what your saying but how would I get it to the 6/12?

geezer#99 11-18-2013 08:02 PM

Re: Edelbrock Carb Help
 
Put #6 on tdc and #1 will be at 6/12.

78maliburat 11-18-2013 08:12 PM

Re: Edelbrock Carb Help
 
Wow........when you advance the timing you pull the dist by the vac canister towards you the front of truck youre idle speed will pick up and when you retard it you push the canister towards the firewall youyre idle will decrease....................set idle at approx 2000 rpm and turn the dist to the point you get the smoothest idle.tighten it down lower youre idle now done

77ChevySharkBite 11-19-2013 01:06 AM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by 78maliburat (Post 6371032)
Wow........when you advance the timing you pull the dist by the vac canister towards you the front of truck youre idle speed will pick up and when you retard it you push the canister towards the firewall youyre idle will decrease....................set idle at approx 2000 rpm and turn the dist to the point you get the smoothest idle.tighten it down lower youre idle now done

Yeah I know it doesn't make sense it confuses me too but yeah when I get a chance that's what i'm going to do.

bnoon 11-19-2013 10:23 AM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by geezer#99 (Post 6371011)
Put #6 on tdc and #1 will be at 6/12.

Correct, since the cam turns at half speed the marks will line up at both locations. It's just easier to see at 6/12. If you have the marks at 6/12, rotate the crank one full 360 degree turn, the marks will now be at 12/12 and ready to drop the dizzy in at #1. One more 360 degree turn they will be back at 6/12 (you can drop the dizzy in at #6 here). If you truly got them in the right place on your 12/12 setup, then they will also line up in the 6/12 position perfectly with the dots's teeth pointing 100% directly at each other.

Cylinder #6 and #1 are at TDC at the same time, just that #1 is ending the exhaust stroke and starting the intake stroke, and #6 is finishing the compression stroke and starting the power stroke.

77ChevySharkBite 11-19-2013 10:25 AM

Re: Edelbrock Carb Help
 
Okay thanks guys! So I guess I get to pull everything off again :lol:

What do I do if it is indeed a tooth off?

bnoon 11-19-2013 12:17 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by 77ChevySharkBite (Post 6372010)
Okay thanks guys! So I guess I get to pull everything off again :lol:

What do I do if it is indeed a tooth off?

Loosen all of the rocker arms, pull the cam gear off, and reset. I highly recommend the 6/12 tooth to tooth method, then rotate to the 12/12 position and recheck with a straight edge. Then you can drop the dizzy at #1.

77ChevySharkBite 11-19-2013 12:23 PM

Re: Edelbrock Carb Help
 
Quote:

Originally Posted by bnoon (Post 6372170)
Loosen all of the rocker arms, pull the cam gear off, and reset. I highly recommend the 6/12 tooth to tooth method, then rotate to the 12/12 position and recheck with a straight edge. Then you can drop the dizzy at #1.

Okay thanks but it might also would help if I put it at 8* advance and also get that set straight before I pull it off again?


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