350 sb stumbles, timing is 51' retarded

can is for the tranny The dizzy can only go in one way, got a - on the bottom, distributor was getting vacuum from that line also going to the butterfly plate in the front of the carb, very tiny, like the vacuum advance can. I have proper rubber vacuum block offs, which I utilize brake booster is connected to the manifold, pcv is connected to carb plate in the rear I'll try switching pcv, and brake booster, and also try closing the gap a little on the plugs.

 

Move your plug wires till she runs smooth. I would bet you have #1 on the cap at the 6 or 6:30 position as points ignitions not at 5:30.

 

There are no unused ports on the carb. spacer is an open port, I'll have to switch to in individual port thanks

 

will def check that out, thanks guys

 

Thanks for all of the help guys, If I did not directly respond to you, then either I misse dyour post, or already answered in kind. I will clean the plugs, and re'gap them to a lower gap, adjust the fuel at idle, and replace the spacer to a four hole one. I'll try to play with the vaccum guage a little today.

 

Keeping it simple, you need fuel, timing, and spark to fire an engine. Your timing sounds correct, although if its bouncing around you might have a worn dist shaft bushing or broken spring in the dist, but it should still run, next, forget the damper you checked for top dead center right? rockers opened and closed then compression out the spark plug hole. thats tdc, and at tdc your rotor is pointed at #1 then check the order from there.

Then perhaps a little coaxing of fuel down the carb, it has to fire. I remember back years ago the chevy gys messed with 2 cylinders firing order to smooth the engine out but that was over 7000 rpms.... is the vortec firing orser the same as the rest? if not you might have a vortec cam. Ford guys put 352 cams in 302's and changed the firing order to 351. Just a thought and goofd luck

 

Vortech uses the same firing order.Ithink every sbc ever made used the 18436572 firing order.
Although,their are aftermarket cams that switch cylinder 4&7.
I guess he could try swapping those two wires,just to check.
I doubt this is the problem,but stranger things have happened.

 

Ok swap 4 and seven plug wires, got it, on the list, thanks again guys

It bounces around because of slop in the timing chain, needs a new one, on "the list"

 

This is what I would do... Been there done that!!!

 

the carb in the picture is a 600 possibly a 650. I thought 650's and bigger were all dual feed, thats a single feed. I have run 850 cfm on 302s with no issues, but if the carb is too big it would still allow it to start, just get a big bog when you punch it. LoL I surmise the jets are around 60s and 850cfm comes 84 squared usually. Either way it is deffinatly not an 850 cuz of the single feed..... Good luck man, its tough when its your ride.

 

Id make this first on the list.

 

more pictures carb specific



o-ring was dry-rotted, instead of waiting to get another kit I fixed the problem with a little room temperature vulcanizing












enjoy, remember, I have more on my photobucket

 

"can is for the tranny"

I believe the can, next to the valve cover, is a vacuum pull can for the exhaust manifold valve.

 

That carb looks scarry. The transfer tube has J.B. Weld on it. The choke housing is gone and it will pull vacume there. The bowl vent arm is mis-aligned and the rubber stopper on top of the bowl vent is really a piece that goes underneath the accelerator pump. If that last piece is missing it will never run right. Just trying to help.

 

Yes, it is. ^^^ Look at the link rod out the bottom of the can...it attaches to a vent on the exhaust manifold. An "Iron Butterfly", for the Heavy Metal guyz on the HAMB!

 

well I can't get everything right, Honestly didn't know I had one of those.

 

not jb weld, room temperature vulcanizing, or rtv for short, the kit supplied o ring was dry rotted and broke leaking fuel everywhere, the plunger, I think I still have. had no idea, other carbs have had a similar rubber design, so I did it like this. wasn't aware a choke housing could pull vacuum, the choke is a linkage style only, with no elevation adjustment included. I really could have used a more comprehensive rebuild nstruction with more pictures "I am a Marine after all" good to know though, thanks. I am a member of holleys forum, but alas there are no mods to approve me so that I can post in the intro section and start asking questions, even sent a complaint, but no dice.

 

so disconnected, is that causing my problem?, this side sounds a bit like an exhaust leak, but everything is tight.

 

I assume that the people at Holley properly identified your carburetor. I can almost read the List number on the choke horn on your last photo. I agree that you are losing the advantage of a dual plane manifold without a 4 hole spacer.

I also wonder about the accelerator pump since the check valve for it is on the bowl vent. The accelerator pump provides a shot of fuel when you push the accelerator pedal to prevent a stumble until the fuel system catches up and you have a stumble. There is an adjustable linkage to get the shot of fuel timed just right. Can you see it squirt when you open the throttle

Depending on what the carb was used on previously, you might need to change jets to get the proper fuel mixture. There are various power valves that can be used also.

I don't trust those advance timing lights, I've found some that read wrong.

 

the accelerator works, replaced the entire plenum, very similar to what is found inside of the vacuum actuator for the secondaries. guy I gleaned it from said it came from a running 454, couldn't believe my luck I used the same jet from the kit, and it is definitly getting waaaaay too much fuel. the idle screws can be adjusted even further in at least for idle, however, there is no bog when accelerated, unknown under load since she won't run under load "flooded?" but still stumbles the same. I will check this out further still tomorrow, as today was a family day, not a truck day. "the BOSS insisted"

 

The timing mark should be a cut line across the balancer. Snag a 5/8 socket and put it on bolt in the center of the crank snout. Turn the engine over slowly by had it will show up for ya.

I am looking at your carb and I am going to say that your problem is most likely with the carb. It could be any number of things that are not copacetic.

You do not have to use the o ring supplied with the carb rebuild kit btw. You can buy O-Rings at about any hardware store. Just take the balance tube and float bowl with you.

If I were closer I would loan you a carb to try out. I am going to go out on a limb here and say that there are no HAMBers on base. But there are tones of HAMBers in your part of the country maybe one of them will step up and give you a hand.

Don't let it get you down, you can overcome this. No hill for a stepper.

 

Issue #1, you are hooked to FULL manifold vacuum to your distributor with the hose going under the front bowl to the throttle plate. That hose needs to go to PORTED vacuum in the passenger side of the carb in the metering block.

 

It's floating around on the front of the air horn. It's in one of the pictures, but I can't make it out.

 

KD, set your idle FUEL mixture screws to 1 1/2 turns out from LIGHTLY seated as a starting point. You must also check and set your fuel LEVELS as this can and will result in a condition like a rich fuel mixture if the floats are adjusted too high. Could explain your " way too much fuel ". There is some sort of block-off plate on the passenger side of the intake under the carb. Looks to have 2 socket-head cap screws, { Allen bolts },in it, maybe 1/4X20. If so, does this seal 100%, if not you need to correct this. TR

 

Also, is there anything holding your choke plate from closing when its running? I dont see any electric or mechanical choke mechanism, nor do I see any type of rod going to the choke plate.

 

P.S. thanks for your service Kevin, I only wish you were closer, I would personally make sure you were running and running as good as it could ever get. LAND OF THE FREE- "because" OF THE BRAVE!! THANK-YOU, TR

 

I'm not necessarily disagreeing with you,TR,but some of my engines have seemed to run much better with advance connected to full manifold vacuum. Especially if the vacuum pot didn't contain a lot of advance.

Also,what would you suugest if the carb was an older one that didn't have a ported vacuum source?

 

Agreed, ever see the NAPA master book with all the vac cans listed, a crazy amount of part numbers. I didn't see where the O/P mentioned a performance cam that might cause a low vac condition, maybe I didnt see that or he didn't say. We are all just stabbing here, so many things it could be. I would just like to see him change to ported vac, and see if that' brings things around to somewhat normal. Wouldn't cost a penny, and take all of 2 minutes to check. Thanks buddy, TR

 

I was thinking that myself,TR.
Thank you for your service,Kevin.
Wish I could fix it for ya,too,young man.
Come on,Cali HAMBERS,someone help this guy out.

 

Bob, maybe this will help you out better. I see the HEI distrib, and I think of emission requirements era. Us old guys and traditionalists remember full ported manifold vacuum for the advance can. Then came emissions and lazy ways to reduce exhaust emisions. The engineers moved the port from below the throttle plate to above. These engines had little or no vacuum at the port at idle. Long story short, these port timed vacuum advance engines had rediculous amounts of timing built into the distributor. The vacuum can at idle now didnt really do much at all. These engines were not set up like the usuall 12-14 degrees BTDC initial, they were like 2-4 BTDC, and some were even AFTER TDC. The advance can worked while light load cruising, but nothing at idle. The engineers even went as far as injecting airinto the engines for the lean-burn, remember the air-pumps. This is why I suggested the ported side for the vacuum can. I have to get back, hope that helps better than before, TR