'72 no start

[Enginebuilder]

I've given up for the night, hoping that between now and morning something will change... Perhaps bright sunshine and a fresh perspective will fix the problem.

The Truck:
1972 fleet side, mostly original

The Motor:
GM 350 cu. in. crate motor installed last year (previous owner)
Offenhauser dual-plane high-rise intake
Holley 4bbl carb
what appears to be a no-name HEI Distributor
Accel 8mm spark plug wires

The Problem:
No start. No popping, no backfiring, no nothing.

This truck 'worked' 36 hours ago. In that time, I've rebuilt the carb, replaced spark plugs/wires, replaced the rear brakes, re-wired the turn signals, brake lights and running lights.

What I've done to *try* to get it to start:

• Gasoline through carb; figured that the carb, having just been rebuilt, would be empty of gas, so I opened the throttle and dumped a little gasoline in it. Nothing. (the carb is now FULL of gasoline, and the mechanical pump is pumping plenty of fuel)

• Brought cylinder #1 to TDC on compression stroke then realigned rotor to point directly at #1 spark tower. Nothing

• Hooked timing light to each and every spark plug wire, just to confirm spark; checked out okay.

• Went inside, drank a few beers, then went back at it- thinking it might have been flooded. Still no start.

• Loosened distributor and physically moved it in about 5* increments throughout its range of motion. Nothing...

At one point (prior to moving dist.) I got the motor to catch (by adding gas through the carb), but my helper had the pedal to the floor, and the linkage stuck- the motor raced like crazy (sounded great!) and then she killed it with the key. It has not started, or even attempted to start, since.

Prior to all of this, the motor was running like crap at idle; loping along like it had a top-fuel cam in it; the carb itself leaked gasoline like a sieve, and had a bunch of varnish in it. Needless to say, fuel mileage was atrocious.

This was 'supposed' to be a simple 'rebuild the carb, give it a tune-up, and put new brakes on it, and we'll be driving it around town by the weekend....

I'll be picking up a can of starting fluid in the morning, just to see if it will catch and start on that...

If you have *any* ideas on what I might have done wrong, don't hesitate to throw it out there.

[Lee H]

Have you confirmed there is spark? Sounds like the HEI module to me.
Posted via Mobile Device

[Enginebuilder]

Thanks for the reply, Lee, but I checked spark by putting the timing light on each spark plug wire, then cranked the motor; each cylinder lit the light. I pulled a couple of the plugs out, (drenched with gas) then tested them, and they lit as well.

Right now all the plugs are out of the motor, and I'm going to re-time the thing *first* thing in the morning; get my mechanical timing re-set (I moved the dist all over the place) and try it again.

[Lee H]

The plugs may not fire if drenched. Sounds like your timing is way off.
Posted via Mobile Device

[Longhorn Man]

put your timing back and screw in some new spark plugs. I agree with your "I flooded it" theory.The fact that it fired and ran great kinda proves it.

[8.1PWR]

It acts like my truck did. My problem was the timing chain jumped. It stripped 4 teeth off the cam gear. I had to replace the timing chain and all was well again. The other problem was that when I tried to start it, and the engine being an interference engine I bent some push rods.

[Enginebuilder]

Flooded is right.

Still can't get the truck to start, but now have a good idea as to why.

On todays attempt to start, I heard what sounded like liquid being compressed, and the starter *did not* want to turn the motor- hydrolocking?!

Pulled all the plugs, and cranked the motor- fuel came SPRAYING out, so much that I was seriously concerned about a fire.

Going to pull the carb and replace it with a known good one. Back to the drawing board on the old carb... Not sure what I did wrong with the rebuild, but somethin aint right.

Will keep ya'll updated on how it goes.

[72lb4x4]

That much fuel suggests a stuck float, or something in the needle/seat.

Check the oil. You may have gas in there...

[68gmsee]

Whoa! I'm surprise you didn't notice the strong fuel smell with the cylinders full of fuel. Usually the first indication.

As 72lb4x4 mentioned, gas could be in the oil. I'd drain that sucker completely. Leave the plug out while you do the rebuild and change the oil filter also.

[Enginebuilder]

Originally Posted by 72lb4x4

That much fuel suggests a stuck float, or something in the needle/seat.

Check the oil. You may have gas in there...

Needle/seat seem fine, but I'll know more in the morning. Holley 650 double pumper installed, letting the battery charge overnight.

Oil is toast; was bad to begin with, but wanted to wait until I get the darn thing started before I change it out; no use wasting another 5 quarts. Same with the coolant; It's currently low, but if I top it off, and have to tear into the motor again, then I'll just be wasting good coolant.

Right now the priority is to get it to start under its own power. When that's accomplished, I'll do the rest of the regular maintenance. (oil change, coolant flush/fill, etc.)

[BlackTopMotors]

Back up carb is a goodddd idea as all the others..change out oil...timing.

Sometimes backing up a bit helps to see whats up. From the sound of it, it is just majorly flooding.

Interested to hear if the carb change fixed it (a double pumper, you are into fuel;-).

Hope you get it squared away (got an extinguisher?)

[GASoline71]

Originally Posted by Enginebuilder

Needle/seat seem fine, but I'll know more in the morning. Holley 650 double pumper installed, letting the battery charge overnight.

Oil is toast; was bad to begin with, but wanted to wait until I get the darn thing started before I change it out; no use wasting another 5 quarts. Same with the coolant; It's currently low, but if I top it off, and have to tear into the motor again, then I'll just be wasting good coolant.

Right now the priority is to get it to start under its own power. When that's accomplished, I'll do the rest of the regular maintenance. (oil change, coolant flush/fill, etc.)

That much fuel in a cylinder bore almost guarantees a lot of fuel in your oil. Pull the dipstick and see if you can smell fuel. You run that thing for any length of time you run the risk of bearing failure. To get it to run briefly is one thing. But I wouldn't drive it until you get the fuel saturated oil out of the crankcase.

Gary

[Enginebuilder]

Guess I should have clarified-

Yes, the oil smells like gas. It is thoroughly contaminated. Oil change is scheduled for about 45 seconds after this motor starts and runs on its own.

Once the oil/coolant gets changed out, it'll be time to tune the carb/adjust timing. Way I figure it, no point in changing the oil if it's just going to get contaminated again.

got an extinguisher?

Absolutely. Extinguisher is on hand, with the pin already pulled, just in case.

If the 650 runs this motor, it's going to stay; it needed a home anyways, and I can't think of a better place for it.

[Enginebuilder]

Quick update-

Known good 650 double pumper installed last night, let the battery charge overnight.
First attempt saw gasoline spray from the primary vent tube; removed the needle/seat assembly, cleaned it out, and VOILA! Engine fired right up. Sounds damn good, too; I haven't set the idle or anything like that, gotta clear up a fuel leak, change the oil, top off the coolant, then I can start the tuning process.

OMG, this truck has given me fits, but it was all worth it- just listening to it run was enough to justify all the work done in the past week.

Will be sure to post pics of the truck as soon as its tuned and clean.

[BlackTopMotors]

Running is a good thing! Glad its working out for you!