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Discussion Starter #1 (Edited)
So besides an exhaust leak my car was running PERFECT. I was so happy and had no worries that it would make the 2 hr drive to san bruno for my army drill on the 8th.

Yesterday i went and got helicoils put in to fix the leak and now MY ENGINE IS HAVING A MELTDOWN!!

First as i was driving home, i lost spark completely, pulled a wire and was getting super weak spark. Took the ign coil cover off and the holes in the cap for the bolts that hold the coil and its grounds were stripped, giving me weak ground. Walked to autozone, bought new cap, rotor, and coil. Installed, it started and i was able to get it home but everytime i had to stop at a light i had to put it in park and keep it revved up because it wanted to die at idle.

I noticed gas leaking from my electric choke linkage and backfire coming from the carb and at one point gas was pooring in my carb when i turned off the car. I but new plugs in and they were all black on the right bank (helicoil side) and my car smokes like crazy. I tried to tune the carb with a vac gauge and vac would not drop or rise when i tried to tune it, so right now the mixture screws are at 1.5 turns counterclock wise and the smoking has stopped but its hard to start. Timing is 36.

At this point the smoking has stopped, its hard to start, and now i hear a ticking, like a lifter is sticking. What happened?!?! It was running so perfect before the helicoils and now its a complete mess!

Please help!

Chris

P.S. ive quadruple checked the spark plug wires and they are in the proper firing order: 1-8-4-3-6-5-7-2
 

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What is your initial timing at? Sounds like you need a carb rebuild. Fuel pressure to high, fuel pump no good. Might be hard to start depending on what your initial timing is set at. Try to retard the timing to see if it will start easier.

Weak ground from your distributor will cause all sorts of problems, weak starting, no starting, back fire through carb.
 

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The things i would check, would be to double check the timing. How old is your harmonic ballancer. I was working on a Fxxx pickup and couldnt ever get it to run right. After fiddling around with it for a couple days. i noticed that the HB was vibrating around on its hub. I pulled it off and checked the rubber bushing and it was all cracked up. I replaced the HB and started the truck up, and put the timing light on it. It was about 4 degrees off. After seting the timing back, it ran perfect. I dont know if changing your cap and bug might have made a difference, but its worth a check.
 

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Discussion Starter #4 (Edited)
Initial timing is around 15-16. Timing at 3000 rpm is around 36. I think your right about something being wrong fuel side. The linkage of the electric choke is leaking and whe i shut off the engine, fuel is literally pouring into my carb! Im about fed up with engine. Everytime i fix something, it finds a weakness somewhere else, attacks it, and sets me back again... :horse:

P.S. when i get it warmed up around 180, it stays running and stops smoking. Could that be the choke not working correctly, causing too much fuel to enter the carb? Its set to 1 notch lean.
 

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Discussion Starter #7 (Edited)
Yeah i think you guys are right about the float



All that gold is fuel, which has been there ever since i bought it and only now since i have been having these problems, have i noticed fuel leaking off the choke linkage, which is probably coming from the float seal above it. This is a 750 carb (edelbrock 1411).

Upon doing some research i found an article that talks about common problems blamed on carbs and this is what i found.

Problem: My Throttle Plates Are Almost Completely Closed, But My Motor Idles Too High. Solution: In this scenario, air is entering the motor from a source other than the carburetor, which suggests a leak at the intake manifold. "Overtightening the manifold bolts, gasket misalignment, and using the wrong gaskets can all cause leaks," says Brown. "It's a very common problem that results in low manifold vacuum, a high idle speed, and lots of fumes and hydrocarbons out the tailpipe." Murphy estimates that 60 percent of all the cars he works on have a manifold leak. "A small leak may only kill one cylinder, which makes the motor idle rough, but everything smoothes out as the increase in rpm and air velocity moves enough fuel to cover it up,"

At this point, this is exactly what my nova is doing, almost nonexistent vac, super high idle 1200 no matter where i set the rpm screw, and lots of strong fumes and smoke out the exhaust. Again, like the fuel leaking from the float, i noticed and intake leak do to some oil seeping out from it, but my car was running perfect so i held off ripping the manifold off because ive never done it before.

Now it seems, i have fixed my exhaust leak and now my nova has found the float and manifold leak and attacked that, making me pay for my procrastination. Lol

Looks like i gotta do a carb rebuild, which ive never done and looks really intimidating.

And change the intake manifold gasket, which ive never done and looks really intimidating. Lol

Guess there's a first time for everything, any tips on both these procedures would be gratefully appreciated!

Thnx

Chris
 

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Make sure to mark the distributor rotor posistion in relation to the housing before removing. And or take a picture with the cap off for putting it back together. Carb rebuild comes with directions, intake manifold only use the intake to head gaskets. Use good RTV for front and rear valley to intake, and don't be shy with it. Throw the rubber ones they give you in the round filing cabinet.
 

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Make sure to mark the distributor rotor posistion in relation to the housing before removing. And or take a picture with the cap off for putting it back together. Carb rebuild comes with directions, intake manifold only use the intake to head gaskets. Use good RTV for front and rear valley to intake, and don't be shy with it. Throw the rubber ones they give you in the round filing cabinet.
You can make sure #1 piston is at TDC, can research how to do this. If you do this and you don't get the Dist back in the exact spot (Ialways seem to be a tooth off) you can just 1-8-4-3-6-5-7-2 the wires and be back at it.

Don't use too much RTV, don't want excess coming loose and plugging up the oil pump pickup.

Have an exploded view of the carb. There will most likely be bunches of little parts that want to go everywhere. little springs can really take off. May want to remove the top in a box or similar container so if anything takes off it won't go far. Don't want to scare you, non of this is hat hard books everywhere on these subjects and probably youtube video's
 

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That edelbrock is super simple to rebuild!!! i did it first try. Good thing about edelbrock carbs is that there are no gaskets below fuel level. So if you are leaking gas out of the carb its got to be floats, even if the pressure was too high the floats should stop it.


BTW
IVE got 99 problems but a CARB Aint 1!

LSXNOVA
 

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Discussion Starter #12 (Edited)
I watched a vid of a guy swapping manifolds and he drained out the coolant first, necessary?

Thanks for the manifold sealing tips guys, ill be using edelbrocks gaskets and theyre gasket sealer stuff (gascasinch. I think?). A thick bead of red rtv on front and rear valleys, overlapping both gaskets on the four ends. I alsohave heard rtv on the manifold bolt threads is a good idea, ill be using new edelbrock manifold bolts.

Stabbing the dist right is a big worry for me. Ill mark were the rotor is positioned and take pics sevenzeronova, but im not sure what you meant mpv72 about being one tooth off and just "1-8-4-3-6-5-7-2 the wires and be back at it." Can you give me more info on that? Im sure, if you always seem to be one tooth off, i definitely will.

The carb rebuild kit comes with an exploded view of it and doing the rebuild in a box is a great idea mpv, ill definitely do that. There are to carb gaskets on summit and edelbrocks instructions are confusing... which do you guys recommend using?

http://m.summitracing.com/parts/edl-9266

http://m.summitracing.com/parts/edl-2696

I have this manifold

http://m.summitracing.com/parts/edl-2101

And this carb

http://m.summitracing.com/parts/edl-1411

Thnx guys, your all helping me out so much!

Chris
 

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Yes drain coolant. Yes sealer on intake bolts. I don't use the front and rear valley gaskets at all, just rtv about 3/8" bead.
He means by pulling all the cap wires and moving them to the next tower in order to put the rotor back to where it should be. I think that's what he means.
 

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Discussion Starter #14 (Edited)
That edelbrock is super simple to rebuild!!! i did it first try. Good thing about edelbrock carbs is that there are no gaskets below fuel level. So if you are leaking gas out of the carb its got to be floats, even if the pressure was too high the floats should stop it.


BTW
IVE got 99 problems but a CARB Aint 1!

LSXNOVA
Lol congrats on the lsx swap! One day, when im not a broke a**, i will do that swap and get me a tremec as well. :pray: though my career plan as of now is transfering from army reserve to active duty, so ill probably be a broke a** for a long time. Lol army pay = caca poopoo

Btw, mr. Inventor, your right. My dipstick reeks of fuel!
 

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Discussion Starter #15 (Edited)
So ive bought everything i need to replace the intake manifold gasket, rebuild carb, and ill be replacing the exhaust gaskets as well. Here's the shopping list so far, im on my way to autozone to pick up the rest.

Part#: EDL-1477 Item: REBUILD KIT EDELBROCK CARBS

Part#: EDL-7201 Item: INTAKE GASKET

Part#: EDL-8024 Item: STUD KIT CARB

Part#: EDL-8504 Item: BOLT KIT INTAKE MANIFOLD

Part#: EDL-9266 Item: DIVIDED HEAT INSLTR

Part#: EDL-9300 Item: GASGACINCH 4 OZ

Part#: SUM-900037 Item: CARBON AND GASKET SCRAPER

If marked the rotor and taken pictures


Drained the coolant, removed the carb, moved the alternater off the bracket

Upon looking at the way the intake ports are shaped where the carb sits, i wish i would have bought the adapter, but edelbrock says the gasket i bought will work, so i guess it'll have to do.

So far it's easier then i thought it was gonna be, with only one bump in the road (i need a star socket to remove alt bracket, gotta go get on) but i guess even a monkey can disassemble something. Lol

Next up is cleaning the surface, remove hoses, remove alt bracket, and pull distributer.

Chris
 

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Discussion Starter #16
So everythings off and now im just waiting for parts to arrive

Any suggestions on what to clean my intake with? I have carb cleaner and was just gonna scrub it down with that. I was gonna bathe it in lacquer thinner but it has teflon tape and a gasket on the egr blocker so that's a no go. I was gonna bathe the carb in that when i take all the gaskets off, is that ok?

Thank god all the rods are straight, i think i woulda cried if one was bent. Lol

What should i put in the valley when i scrap off all the gasket and stuff? I was gonna put a clean rag there but im not sure it would catch everything.

Apparently the previous owner thought it was a good idea to use every bolt in the world BESIDES a $10no set of manifold bolts... :slap:


So far, so good, just need some suggestions from the ever knowledgeable ppl on this awesome site. :yes:

Chris
 

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changing that intake manifold gasket is a snap, just make sure to use plenty of silicone/rtv in the proper areas.

As for a carb rebuild I'd recommend getting a dvd and a book. With complicated stuff like that a dvd works great.

Just go slow and take your time. If you're not sure just ask. You'll get it done!

Oh and get all sealing surfaces completely clean and oil free!
 

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Don't use a cloth towel or anything like that. If any cloth gets stuck your screwed. Your suppose to use paper towels in the valley there it will just burn up and go to nothing, cloth will stay.
 

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Discussion Starter #19


Everythings buttoned up and out back together, you guys were right, it wasnt that bad. I took my time with everything and placed everything in labelled ziplock bags during the carb rebuild as i went along. Making it really easy to reverse the process during assembly

I have the idle mixture screws at 11/2 turns counterclockwise, idle set around 800 rpm. Timing around 15-16 and full timing comes in around 36 at 3000 rpm. No smoke coming from the exhaust.

But...

It kinda chugs like a train from idle until about 1200 rpm, smoothes out until about 3500 rpm, then it kinda acts like it's hitting a governer, then smoothes out again.

Here's a video of it idling, hopefully you can hear what i'm talking about
http://s1261.photobucket.com/albums...tion=view&current=2012-09-01_12-11-10_376.mp4

Any ideas of what this can be?

Chris
 
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