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-   -   Help! Engine died... (https://67-72chevytrucks.com/vboard/showthread.php?t=379537)

snowblind 01-05-2010 01:11 PM

Help! Engine died...
 
I leave a friends house last night, drive 3 blocks, all of a sudden the engine coughs twice, sputters and then dies. It will crank fine but it won't even attempt to start. It was cold and dark last night so I had it towed home.

So... Fuel, air, spark right? I'm pretty sure the fuel and air are fine but I'll double check. My truck has the GM HEI distributor. What all is involved in the electrical end of equation?

I've been doing a bunch of work under the dash recently. Are there ignition related fuses or wiring that I might have disturbed. Is any of the ignition fused?


Matt

fun in dirt 01-05-2010 01:25 PM

Re: Help! Engine died...
 
Quote:

Originally Posted by snowblind (Post 3712085)
It will crank fine but it won't even attempt to start. Matt

I'm confused by this statement...do you mean it cranks but then won't pull off without going dead again:confused:

If that's the case i'm guessing it's not electrical... especially if it sputtered before going dead.
Maybe the fuel pump?

snowblind 01-05-2010 01:55 PM

Re: Help! Engine died...
 
Quote:

Originally Posted by fun in dirt (Post 3712109)
I'm confused by this statement...do you mean it cranks but then won't pull off without going dead again:confused:

If that's the case i'm guessing it's not electrical... especially if it sputtered before going dead.
Maybe the fuel pump?

Sorry. Cranks but won't catch at all. Car sputtered when it died and does nothing but crank now.

I'll pull the fuel line and see if it flows when cranking. I'll also pull a plug and make sure it's sparking. Not at the same time of course!

Is there any failure other than fuel pump and fuel filter that could stop fuel. Anything in the carb or choke that could suddenly fail?

Thanks. I'm used to working on little jap motors so V8s are sort of "foreign" to me. LOL.

snowblind 01-05-2010 04:38 PM

Re: Help! Engine died...
 
I checked it out a little at lunch. I can hear and smell fuel being squirted into the carb. I pulled the "+" wire from the HEI and and tested it. It shows 12.3v when the key is in the run position.

I couldn't test for spark because I had no one to help me crank. I did pull a plug and looked pretty much perfect color and condition. I'll check for spark tonight when my wife can crank.

Right now I'm thinking that I won't see spark. I think the "module" in the HEI has failed. Time to do some searching of the archives.

fixit-p 01-05-2010 04:54 PM

Re: Help! Engine died...
 
Do you have anything connected to the Tach terminal on the dizzy? If yes and it shorts to ground it would kill your spark.

snowblind 01-05-2010 05:01 PM

Re: Help! Engine died...
 
Quote:

Originally Posted by fixit-p (Post 3712461)
Do you have anything connected to the Tach terminal on the dizzy? If yes and it shorts to ground it would kill your spark.

Yes. Wire runs to a tach in the dash.

I've been reading that module failures on HEI are common enough that people carry spares to avoid being stranded...

fixit-p 01-05-2010 05:11 PM

Re: Help! Engine died...
 
Quick test would be to disconnect the tach at the dizzy and see if it starts

snowblind 01-05-2010 05:22 PM

Re: Help! Engine died...
 
Quote:

Originally Posted by fixit-p (Post 3712497)
Quick test would be to disconnect the tach at the dizzy and see if it starts

Very true. I just found this in another post -

"The other lead (firewall side) is for a tach, or if you want a nice ignition cut-off or kill switch, run the tach lead to ground threw a switch."

I did some stereo wiring recently so it's very possible that the tach wire is pulled around and shorting out. I'll check tonight.

Thanks.

snowblind 01-05-2010 09:15 PM

Re: Help! Engine died...
 
Checked spark with a plug pulled and grounded on the exhaust mani. No spark with or without the tach wire attached. I guess I'm off to Napa for a cap, rotor, coil and module...

1949gmc 01-05-2010 10:19 PM

Re: Help! Engine died...
 
Sounds to me like the module. That's happened to me a number of times... in fact, when I read that it sputtered and died, my first thought was 'It's the module.' Make sure you put the gel underneath it before you put it on, otherwise it'll get hot and go bad again. Have fun!

snowblind 01-05-2010 11:17 PM

Re: Help! Engine died...
 
Quote:

Originally Posted by 1949gmc (Post 3713193)
Sounds to me like the module. That's happened to me a number of times... in fact, when I read that it sputtered and died, my first thought was 'It's the module.' Make sure you put the gel underneath it before you put it on, otherwise it'll get hot and go bad again. Have fun!

Thanks for the advice. Now I'm trying to decide between rebuild versus upgrade. See the new thread at http://67-72chevytrucks.com/vboard/s...14#post3713314


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