I need a second opinion

I am baffled! I'll get to the point.
SBC 383, I have a hot spark all the way to the plug tips, gas is good, compression good, the timing mark on the balancer at 0 degrees on the compression stroke and the pointer at #1 on the cap. No fire, no sputter, nothing.
It's a new engine that has not been driven but has a couple hours of running time with no problems. I was setting the idle mixture screws and doing some tuning when it started to get hard to keep it running and idling. I quit for the day and when I went back nothing. I checked the plugs and they were gas fouled. I replaced them and then the coil just to be safe with no luck.

 

No info here..

I will have to make assumptions;

Plugs wet. Sputtered/died.

If the spark went away, the plugs would not get that wet.

So, i will assume the float/needle stuck in the carb, which flooded the cyls.

Don't keep swapping in new parts, diagnose it first.

 

Check your condenser if you have points. HRP

 

My guess. Flooded.

Pull the plugs crank it and let it dry out.

 

Need more info. What carb, distributor, fuel pump, etc.

 

Additional info.
HEI, MSD 6 box, Accel coil, NGK v-groove med heat range plugs.
Edelbrock 750 carb and airgap intake.

When it failed to start I triple checked the timing marks to make sure it was set correctly even though it hadn't been changed. Hot spark to plug tips. Yesterday I pulled the plugs and squirted oil in the cylinders. I rolled it over with the plugs out to make sure it was dried out and good compression. I pulled the valve covers and checked the rocker arm movement to make sure everything was good there.
I diagnosed and checked everything before moving on and replacing any parts. I was thinking the gas fouled plugs were from the carb being too rich/numerous starting attempts. I did check the carb and I had installed new metering rods to make it 4% leaner.
Please let me know if you need any additional info. Thanks

 

HEI module?

 

No HEI module with the MSD box. It has a hot spark all the way to the cylinder.

 

With fresh plugs, try some starting fluid or carb cleaner.
If it doesn't putter you most likely have an ignition problem.

 

I thought of trying the starting fluid but didn't have any handy. I'll give that a try. Maybe that will eliminate something from the list.

 

Make sure you have the + positive side of that MSD box to the Battery,same for the ground.

MSD is very picky about that and if you call their Tech line it will be the first thing they will ask ,and then advise you to do.

I am not saying that is the problem,only something to check on.

 

Go back to basics. It was running. You were playing with the mixture screws and it got worse and quit. Plugs were gas fouled. That tells us one of two things, either you managed to adjust it really rich, or the ignition took a crap. So the logical diagnosis is to check the spark. You've done that. So try new plugs. See if the plugs fire before you put them in the heads. If the do, put them in the motor. Try and start it. What happens? If it doesn't fire, pull a plug and see it they are wet. If they are, you are flooding it - may be a stuck float? I would also bump the timing up a little - it it is at TDC (0°) it is too retarded

 

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I installed new plugs and checked to make sure I was getting spark all the way to the tip. Another thing I just remembered. At one point while running the tach bounced and acted strange. Could it be the MSD box? I am getting spark?
After adding the new plugs and coil and checking to make sure there was spark all the way to the plug tips, I tried starting it and nothing. Pulled the plugs and they were dry.

 

try some gas in carb. BE CARFULL. A little just to see if it fires.

 

Don't pour gas in, you could easily foul the new plugs (or worse) - get some starting fluid!

 

Disconnect the tach from the msd box and try again. I've seen tachs short out ign systems before.

 

And you have not adjusted the timing since last ran? The timing mark may not mean jack.

 

here i just reached in slightly under the hood and WAVED my hand across
the engine....
a lot of the carb sprays are horribly watered down S#!T and *ether*(startingfluid)
can be verry volatile, snappy...so don't spray too MUCH...


other than that we here for ya doing the best we all can...




there will be some boasting and BS later here, i'm sure of it,
as the key board commandos, read then re type info as if they actually know something.
and boy boy are they stubborn to learning anything different than what they think they know.

 

any possibility the exhaust is clogged? mouse nest?
seen it happen more than once.

 

i think he said it was / had it RUNNING for a few hours...

 

i was thinking something moved inside.

 

kool .... hope the OP tells us what the fix (was)

 

Did you happen to add gas to the tank just before it stopped running?
If so, at a station, or from a 5 gallon can?

I'd disconnect the fuel line at the carb, point it into a clean pyrex cup, and crank the engine to catch a gas sample. I'm thinking water in the gas, or maybe somebody mixed up the diesel or kerosene pump for a gas pump.

As others said, a squirt of dry gas or excellent fresh gasoline down the carb throat after new plugs are installed should get a few seconds of running even if the fuel system is bad.

 

Check the MSD box. If you wired the power to any source other than they recommend, you will have a problem. (a warranty problem, that is...if you got a 'spike', you could have burned the inner circuits)

The erratic tach reading hints to such an 'event'.

 

try a different distributor (non-hei)

An MSD box is hard to kill, but an HEI has a few weak spots

 

I was thinking it might be ignition but I had good spark. The car ran great. I adjusted the idle mixture screws and everything was still good. I thought about playing with the timing but hadn't got to it when the problems started. I sat in the car to see what the idle speed was and then the needle went crazy. It then showed it was idling at 1800-2000 but I knew that wasn't right. I tried to set the idle down a bit but it got to where it wouldn't idle at all. I haven't been able to get it to fire since.
It has gas in the tank. I put some in a couple weeks ago out of a 5 gal can that I just filled at the same time I filled up my truck. The tank, lines, etc. are all brand new.
I recalibrated the tach by the instructions and found it was now off. It was now no longer set on 8 cyl.

 

Hmm, I wonder.....haven't seen it in a long time, but what about improperly adjusted valves? Lifters pumped up after running a bit.... You know its so much easier to fix something when its in front of you rather than over the net.....

 

start over..

Pull all the plugs, are they all dry, or a bunch are wet?

Leave them out for now. Then pull the center wire out of the cap if that is the kind of cap you have on that system. Put one plug attached to that main coil wire coming from the coil, and lay the plug on the motor. Crank the engine and it should spark at each cylinder.

If you have good steady sparking, i assume it is a gas problem. If the plugs were dry, does the accel squirters squirt with one full movement of the carb linkage?

or if the plugs wrre mostly wet, does fuel dribble down inside the carb as it is cranking> If yes, the needle is open, stuck with debris or the float is hanging up, or sunk.

 

I know what you mean. I have the car in front of me and still haven't figured it out. The valves should be ok. I've had the car running the last 5-6 Saturdays straight with no problems.