Cold start issue Michigan

[RUBBERSIDEDOWN]

i just did a swap and installed (buddy did most work) a 360 with cam, edlebrock carb and manifold with some other tweaks. It had 3k on rebuild and it rolled once. it sat for about 1.5 years. the prev owner took good care of it and it ran fine. the cold start was funky but it ran ok once it was up and warm. i might also add that it has a leak in the left manifold/exhaust gasket which will be fixed soon. my buddy noted the cold start issue and said he felt the black choke unit on the side of the carb was supposed to have a ground wire. it only had the slip on positive wire and when he ground it, he said the butterfly closed or opened right up. since then when cold start it revs up and idles way too high. the oil pressure is up around 60 and it sounds like the pedal is half way down.

this spooks me as i know cold and revs that high dont mix. if you tap the pedal again too soon idle drops and it rumbles and farts. if you let it idle high long enough and tap it, the revs come down but it takes about 10 plus minutes in 30 degree to idle smooth. it also will surge a bit at low speed acceleration kind of like when you have a bad plug wire that is wet. at steady throttle around 20 mph it will surge slightly. It also has the HEI distributopr. Soooooooo question is, any ideas as to what might be happening? It was a recent install so a line or something could be bad etc.

The other question is I have been told to cold start, turn key on. Press pedal once and release, then start it. When I do that it starts bang right away. I saw a paper from wagonmaster that showed cold start to be turn key on, push pedal all the way down and release and hold it have way, then start it. What is the proper way and does the fact it has edlebrock carb change anything?

Thanks in advance

[vintagetrks]

To me it sounds like your intake leak may be a large part of the problem also your choke not operating properly compounds the issue. There may also be another smaller vacum issue but it's hard to tell until you address the major issue of the leaky manifold. IMHO

[men in black]

Welcome aboard from Grand Blanc

I can't help on the cold starts, my GW is in storage.

But we do need pictures

[brad_fsj10]

The other question is I have been told to cold start, turn key on. Press pedal once and release, then start it.

This should work fine for you.... non-stock carburetor.

I saw a paper from wagonmaster that showed cold start to be turn key on, push pedal all the way down and release and hold it have way, then start it.

If you had a stock carburetor with the anti-dieseling solenoid, this is the correct procedure.

Since you don’t have the stock carburetor the first way should work for you. YES, the choke must have its own ground. The fact that it’s bucking and backfiring shows you have other issues. Three things – fast idle speed, choke duration, choke pull-off.

The high cold idle is related to the fast idle screw on the fast idle cam. Look low on the carburetor behind the black choke cover. You’ll see a brass idle set screw. The confounding issue with Edelbrock/Carter carbs is that you need to adjust the screw when the motor is off – you can’t get to it without opening up the throttle plates. Through trial and error, set the fast idle speed to about 1200 RPM (Specs say 1500 +/- 100, but I think that’s way high.

After the cold speed is set, then you’ll want to address the choke duration. You can see the “rich/lean” markings on the side of the choke cover. They are basically useless (IMO) until you set the initial choke pressure. Back the cover screws off until you can rotate the mechanism enough to see the choke plate open. Then, rotate the choke plate clockwise until the plate contacts the front of the airhorn. Then, look at the choke cover and see where you are on the “rich/lean” indicatrors and turn one more notch rich. Tighten the cover screws.

A functioning choke pull-off actuator is essential. Again, look behind the choke cover and you’ll see a little dashpot with an actuator rod connected to the choke linkage. I should also have a vacuum line connected to it. Test the operation by supplying vacuum to the actuator. If it pulls the rod it should be operating ok. When you start the motor, the actuator should open the choke plate (like 7/32”) to a set value. Look at your carb’s specs and set.

After all that, if you’re still having issues – popping, etc. Then yes, vacuum or timing issue somewhere.

[RUBBERSIDEDOWN]

Thanks to all. I will try that in a few minutes I have a buddy coming over that is a master wrench and has a load of carb knowledge. I should say that it isnt real bad popping and farting. it's more just rough idle then stall until it's warmed up. that high rev at cold start is way too high rpm imho. if you tap the pedal too soon (still not warm enough) it will come down rev wise then shudder and stall. Usually after about 2 minutes of high rev cold start idle it will keep running. i hope that gucci gasket set i ordered from BJ's tightens it up. BJ's also showed a valve for the passenger side exhaust that said if the stock one is bad it will run like crap cold. my buddy told me mine looks like it was blocked off or removed. it's an 86 motor in an 89 waggy btw.

[brad_fsj10]

For the rough idle when cold, sounds like your choke pull-off ........ isn't. I just bought a stock one for my 86 at Advance Auto, $25 and change. You'll have to order one no doubt if yours is bad.

As far as the exhaust valve you noted - heat riser valve - it is very important for stock manifold/choke setup/operation. For your aftermarket manifold and electric choke combination.... not so much.... UNLESS it has frozen-up/rusted closed.... then you'll definately have issues. Some aftermarket intake manifolds block the exhaust crossover passage. If the valve is rusted closed it would basically plug those four cylinders.

[jaber]

Welcome to the land of empty pockets and unfinished projects...

These guys are great when it comes to carbs. I dont know squat. I went to a TBI set up and it is untouchable. I'm currently doing a DIY set up and with all the info on the net, it has been quite simple.

And let me be the first to say...

[The PIG Smith]

Welcome from Fort Wayne, Indiana.

[sappy76]

Welcome from SW Michigan

edlebrock carb and manifold

The other question is I have been told to cold start, turn key on. Press pedal once and release, then start it. When I do that it starts bang right away.

Join the club on the edelbrock carb cold start issues. I just converted my Jeep to the Howell TBI system and love it. Adjust the choke idle speed with the screw that's hard to reach. I used to set mine around 1000 rpm.

Tapping the throttle resets the automatic choke. When warm, the automatic choke spring heats up and opens the choke. When the engine cools down, the spring tightens and tries to close the choke however the stepped linkage holds the choke open. When you tap the throttle, this moves the stepped linkage and the spring in the choke forces the choke plate closed.

I'll give you a couple of winters to realize that TBI technology is a good thing.

[jaber]

Rather then "tapping" the throttle, try pushing on the pedal to release the step linkage and then SLOWLY releasing the pedal. On my stock 2bbl, it will step down in idle but not all the way. It will give me a higher then idle, less then racing.
I dont know if this helps, but its what I do in the mornings. Although, I am in the dessert.... You'll be searching for TBI soon, it's VERY user friendly...

[RUBBERSIDEDOWN]

Thanks for the tips. I will get a pic soon. I had a good guy wrench on it yesterday and once warm it's purring pretty well and the high idle is lower when cold. The Edlebrock online manual shows a thin wire and suggests you put it into a notch once you take the elec choke cover off. problem is the guy spent 1/2 hour and said there aint no Great Googley MoogleyGreat Googley MoogleyGreat Googley MoogleyGreat Googley Moogley notch on here. it started kind of crappy this morning but the idle is better and smoother. between 20 and 30 mph during easy acceleration it still kind of surges and hesitates. It's not major like running out of gas would feel but I can sense it. mechanic also suggested gettting rid of all the vacum lines on the air cleaner housing. claims they are redundant and not needed with the carb I have. Said they are all just a potential vac leak and that the valves they are hooked to are probably rotted years ago

[timmy401]

Choke adjustment

It sounds like it is just a ways out of adjustment. When cold, tap pedal twice. What this does is 2 shots from accelerator pump and allows cold choke to shut. If it shuts hard, adjust choke coil until it barely shuts completely cold (Hold throttle wide open while adjusting, NOT RUNNING). Turn key and start. When it starts the choke pull off should only open choke plate 1/8" or so(there maybe a screw for this adjustment or a rod to bend). Tap the gas. With everything else working so far, cold idle screw(yes there is a second idle screw) should fall off the high idle cam's biggest step and onto the middle step. Adjust to around 900 rpm's on this cam (when cold). Now as the choke gets warm, it will fall open until it is not on cold idle screw/cam and on regular idle speed screw.
Hope this helps , it may take a couple cold starts to get this adjusted completely correctly.
Welcome from Grandville , Mi.

[RUBBERSIDEDOWN]

OK, I had the exhaust manifold gasket leak fixed today. It runs smooth at idle when it is really warmed up. The tip on pressing the pedal the slowly depressing it worked to lower the cold idle from super high. The problem that remains is the surge or bogging from 18 to 30 mph. It doesnt lurch like running out of fuel but it feels like it is starving for fuel every few second. Once it gets over 35 or so, or if I really jump on it it goes pretty fast.

As stated its a rebuilt 30. over block with edlebrock carb and edlebrock intake manifold. It also has HEI Distributor. The pipes are stock but they have a cherry bomb inline. One thing that may be an issue (or not) that just occured to me. Mine is an 89 and the donor motor is out of an 86. I think the ECM unit ( I assume that is the aluminum finned block on the drivers side wheel well?) is the 89.

We took the 86 unit out to save for back up. Could the guts be different from 86 to 89 enough to make that ECM cause or contribute? I am just thinking out loud but I am getting tired of this flat spot and hesitation. You would think a fresh motor with only 3k and all that cool stuff would run better. Lastley, I still have the old motor and stock carb. If I keep getting dead ends should I dump the Edlebrock carb on CL and put the stock one on? Perhaps that is dumb but I cant seem to sort it out

[jaber]

The box on the fender is you ignition modual. The only difference in them, that I know of, is that they changed the plugs on it around '85-'86. Internally they are the same.

I think you would be loosing power and performance if you went to the 2bbl.

[RUBBERSIDEDOWN]

I spoke to another mechanic today and he said the hesitation or surging from 18 to 30 mph with easy throttle could be vacuum. He said to spray starting fluid around some of the lines/valves and see if revs increase. i also know if there is a gasket leak under carb etc that will increase revs also. it feel s like someone is letting up on the gas a tad then it pulls like normal. It feels to me like it is leaning out for split second. If I really get on the pedal it accelerates hard and doesnt bog or surge. Problem is, I dont want to get 7mpg by gunning it from every stop.

I dont know if there is a certain line or valve that could affect that range and with those syptoms? Mechanic told me "it could be any line" I thought there would be more rhyme or reason as they each do specific things. The guy that tuned it last weekend said to "get rid of all that vacuum Great Googley MoogleyGreat Googley MoogleyGreat Googley MoogleyGreat Googley Moogley and plug them all....you dont need them with this carb" I just dont want to block off and unplug everything for fear I might mess something up. He didnt mean every line on the vehicle just all the stuff on the air cleaner housing and snorkel