Headers glowing with new intake and carb. Hard starting.

badsnakeii · Aug 25, 2010

I know there are those much wiser than i with carbs here. Its been about 10 years since i have done any hot rodding, and i was never good with tuning carbs.

I just changed the intake and carb and its hard to start now and after 1 min of running at 2500 the headers were hot enough to see the cyl firing. It could be anything. My timing might be off?? but the carb came from holly with factory tuning for my engine build. It back fired and i suppose it could have blown the power valve... Anyway where is a good place to have a lemans solid lifter cam timed too? (running msd mechanical distributor) And what should i do with the carb to start with? The carb is a holly 4777 if i recall correctly. I have no idea where to go from here. Im pretty sure the idle mixture screws are not the reverse turn ones. How far out should i start with them?

Thanks very much. Looking forward to getting back into the game again

Cobra5.0Jeep · Aug 25, 2010

Sounds like your timing is too retarded. Advance your timing.

69gmachine · Aug 26, 2010

Cobra5.0Jeep said:
Sounds like your timing is too retarded. Advance your timing.

Good thing your not in new Jersey, you could go to jail for that advice!

The other thing that could cause it to glow red hot is being too lean. I had a Autolite 4300 that almost killed my engine when I first put it together back in '93. Swapped it out for a Holley and the problem instantly went away. I never bothered to figure out what was wrong with the Autolite because the 4300s aren't worth the effort.

iskwezm · Aug 26, 2010

im guessing too lean too, retarded timing would cause a it to run rough and be down on power.

rbohm · Aug 26, 2010

iskwezm said:
im guessing too lean too, retarded timing would cause a it to run rough and be down on power.

that depends on how retarded the timing is. but i agree that it sounds like you have a lean mixture going on, along with slightly retarded timing.

Cobra5.0Jeep · Aug 26, 2010

When i first got my 532 running the headers were glowing red hot and it was running super rich.
Since you had to pull the distributor out to put the new intake on i still say its not timed right.
Since you put question marks next to "my timing might be off?" i am assuming you didn't check the timing so i would do that.

badsnakeii · Aug 26, 2010

Still wont start like it should. It is timed still at 16btdc. I know how to get the intake off without taking the distributor out. Thats why i do it that way, its alittle more of a pain in the ass but it saves time and headache to re-time it. It sure seems like theres a problem with the timing but i dont know what or why. It doesnt make sense how it can be retarded if the light is hitting 16btdc. If the distributor was mechanicly retarded it wouldnt hit 16deg would it?
And lean? it has 4777 650 holly with 86 jets....

Thanks much and hope we can figure this out soon.

mustangmike6996 · Aug 26, 2010

i would also at least inspect the spark plugs.. running that hot for too long could have damaged some electrodes...

badsnakeii · Aug 26, 2010

No vacuum. Just enough to make the gauge barely move. No reason why there is no vacuum. Pressure tested intake through coolant system and no leaks, held 20lbs for 4hrs. Pressure tested intake through carb, no leaks can be found, though some air can be heard inside the carb somewhere Timing is where it should be.
...Its getting air somewhere or the valves are gone... Set the lash on them cold to .019 and .020 as recomended.
This is BS

badsnakeii · Aug 26, 2010

Plugs are black, like its running rich... and set to .040.

...When i pulled the distributor cap off and it was on tdc, the pointer was past the #1 peg... Say the #1 peg is at 2:00 the pointer was at 1:00. Why? and so i loosened the distributor and turned it untill it tryed firing, and it still wouldnt take off. When it fired it was at 14-16btdc.

restomoded66 · Aug 27, 2010

badsnakeii said:
Plugs are black, like its running rich... and set to .040.

...When i pulled the distributor cap off and it was on tdc, the pointer was past the #1 peg... Say the #1 peg is at 2:00 the pointer was at 1:00. Why? and so i loosened the distributor and turned it untill it tryed firing, and it still wouldnt take off. When it fired it was at 14-16btdc.

Hi! What are you running for ignition, plug gap might be too big for your ignition system. My 351w was over heating; headers were over 600 degrees at idle, engine was really rich at idle, soothed plug and could not get my carb to lean out at idle. I got a duraspark ignition on it and they call for .45" to .55" spark plugs gap. I had them at .55" because bigger the gap bigger the spark and better fuel economy in theory. I regaped my plug to .45" and what a difference, headers are 200 degrees cooler, rich condition when away and no more overheating problem.

69gmachine · Aug 28, 2010

Are you sure your not sucking in oil somewhere? It burns a lot hotter than gas and will make the plugs very black.

ForceFed70 · Aug 28, 2010

90% of the time, glowing headers are a result of too little timing. I would break out the timing light 1st before doing anything else.

Don't let people tell you that it's too lean. While a lean condition can create a lot of heat, that heat is usually contained in the combustion chamber.

It's definately not a rich condition. Rich mixture typically results in lower temps, and contrary to popular belief, the extra fuel does not burn in the headers as there is no oxygen in there to support the burn (unless you've got completely blown out gaskets).

Time it 1st. If the static timing is OK, make sure that your vacum and/or mechanical advances are working.

badsnakeii · Aug 29, 2010

Timed it and it still wasnt right. still wont hardly fire and will not stay running. Pulled the cap off the distributor and then the rotor (running msd 8582 distributor) if you know these distributors they have a square peg and a round peg that are supposed to make it so the person assembling the thing can only put it on one way. Well mine proves you truly can put a square peg in a round hole.
So now what? Since the rotor was 180 out does that mean where we thought tdc was is actually 180 out in the block? how could this thing have ran for over a year with that in there that way? The only way that makes sense to me is that the motor is out 180?
Also i found some pictures of these in cars and the wire coming out of the bottom of the dist. body is straight forward. Mine in my car, where it is supposed to be timed at 16btdc, is over top of the water neck on the intake? This is how it has always been, even after we put the rotor in the right way, pulled the dist. and repositioned it as it should be to tdc #1.
I am going to run a compression test to see if the valves are closing all the way and then i will star over with the timing. Make sure it is actually at #1 tdc and go from there.
Im at a loss with this thing.

bocksta · Aug 29, 2010

Was the car running just before you changed the intake and carb? here a picture of different vacuum situations.Check the one on the bottom left, It does list undersized carb or clogged exhaust as one possibility for little to no vacuum.
You may want to recheck the valve lash. Pull the valve covers remove the coil wire and have someone crank the engine .

badsnakeii · Aug 29, 2010

The lash was way too tight. Its not a flat cam all the rockers make the full lift. I checked into the cam some more. I got three cams in a lot and picked this one...i dont remember why other than the box it is in said "New flat tappet mechanical cam, Le Manes Ford GT40, Iskiderian, Lift (Int) 525 (exh) 562, Duration (int) 356 (exh) 366 *overlap." What does overlap mean? And how is it possible to have 366 duration? All this and i have 1.7 rockers on it.

Relashing valves. That will take a few days. And i still would like to know why is my distributor turned from what all the other guys with the same dist look like? My wires are coming out over the water neck???

What do i do if it doesnt make enough vacuum? Do they make a pump for cars? electric?

Yes it was running, just not well because the intake would not seal.
Thanks again

woodsnake · Aug 29, 2010

My free advice, is to pull the timing cover back off.
Manually turn the motor by hand until the camshaft "dot" and crankshaft "dot" are at the 6 and 12 respectively, I.E., pointing straight at each other.
Take the distruibutor out, and resink it, with the vacuum module pointing towards th radiator, ensuring the rotor is pointing at the number 1 cylinder.
Re-assemble.
Start car.
With the vacuum advance plugged off, adjust the distributor until you get the highest vacuum at idle, at the lowest idle speed.
When it idles smoothly at around 800 or so, you can start making carburetor adjustments. On the drivers side, screw the idle mixture screw in, until the engine starts to stumble, then back the screw out slowly, until you get the highest amount of engine vacuum. Repeat for the passenger side of the carb.

Plug the vacuum advance back in, and test drive. Make minor adjustments as necessary.

Did you measure for correct push rod length? Do you have the correct installed height for the springs? Installing a performance cam is a whole task unto itself, over and above trying to get one running again.

bocksta · Aug 30, 2010

badsnakeii said:
The lash was way too tight. Its not a flat cam all the rockers make the full lift. I checked into the cam some more. I got three cams in a lot and picked this one...i dont remember why other than the box it is in said "New flat tappet mechanical cam, Le Manes Ford GT40, Iskiderian, Lift (Int) 525 (exh) 562, Duration (int) 356 (exh) 366 *overlap." What does overlap mean? And how is it possible to have 366 duration? All this and i have 1.7 rockers on it.

Relashing valves. That will take a few days. And i still would like to know why is my distributor turned from what all the other guys with the same dist look like? My wires are coming out over the water neck???

What do i do if it doesnt make enough vacuum? Do they make a pump for cars? electric?

Yes it was running, just not well because the intake would not seal.
Thanks again

Once the valves get readjusted ,you'll have a better starting point. Restart the engine and recheck the timing . It should run better and you can recheck for any vacuum pressure and leaks.

Headers glowing with new intake and carb. Hard starting.

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