Spark problem solved. Now, on to fuel

[krisnowicki]

http://www.youtube.com/watch?v=_yT9e3r9NZU

A while back I had a couple spark problems, turned out to be a bad module.

Is a video of the engine running today.

It will start and run for 30-180 secs. Then it will either surge then stall or just die. I pump the throttle once and it fires right up. and repeats.


I pulled the carb apart, everything is clean, float is good, gas smells like gas, no water, accel pump pushes a stream of gas out....

Any suggestion?

 

[dubs283]

Re: Spark problem solved. Now, on to fuel

so the carb is okay, how about the rest of the fuel system??

fuel pump, filters, fuel lines, anti-siphon valve, tank pickup, vent and line, etc...

 

[Don S]

Re: Spark problem solved. Now, on to fuel

Does your engine have a year, better yet a serial number?

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

MY thoughts were the same. I replaced the fuel water seperator, pour the old one into a jar and check out the pic attached to this. IT looked good. Fuel pressure is good from the pump, so everything behind it must be good. So I pulled the carb apart again. The power valve in the bottom looks rough but the float and needle are fine... I am miffed.

Timing is at 8 deg btdc done with the shunt, it will run longer the more it gets warmed up. But it stalls at 2 -3 mins no matter what.

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

no serial on engine or cover. but, it is a 2006 non tks 2bbl carbed 5.7 vortec

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

would a power valve not sealing cause this problem?

 

[Technorunner]

Re: Spark problem solved. Now, on to fuel

Had this problem on a boat i worked on, and it was the venting for the fueltank that was clogged up. Not the hose but the metalnet on the outside of the boat.

 

[Don S]

Re: Spark problem solved. Now, on to fuel

Hook up a fuel pressure gauge between the pump and the carb and see if the pressure is dropping off. You may have to make up a fitting or hose between the pump and carb for the gauge, DO NOT cut the steel line to hook up the gauge.

You can also test the fuel system before the fuel pump using this procedure. http://forums.iboats.com/showthread.php?t=167561

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

7 lbs steady

 

[Don S]

Re: Spark problem solved. Now, on to fuel

Is that the fuel pump pressure just as it dies? After it dies, can you pump the accelerator pump and the carb squirts gas out of the accelerator pump? Does it still have spark just after it dies?

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

Has spark at all times. The pump kicks on when then engine starts to turn over, then shuts off after the engine stops running. And once dead, the accel pump will still spray fuel.

 

[mxcobra]

Re: Spark problem solved. Now, on to fuel

I may be wroung-but I think you still got a spark problem......

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

every time it dies spark is still good. the fact that it revs up then stalls makes me think it is "leaning out" then stalling. maybe egr or pcv valve? Also the fact that it runs longer the warmer it gets makes me think fuel too.

 

[krisnowicki]

Re: Spark problem solved. Now, on to fuel

I am at wits end.... tongiht I checked fuel pressure agian. I hooked everything up and it started ran for five ses and stalls. I turn the key and it fires right back up and reves to about 1900-2000 then stalls.

Repeat.
Repeat. etc.

 

[mxcobra]

Re: Spark problem solved. Now, on to fuel

I am thinking bad ground when engine fires somthing is vibrating, making a poor conection temp. stoping spark.
mabie you got a bad module I would get a volt meater and start checking power everywere while shes running and as she dies and before it runs. if gas is good then gas is good! Thats easy to check- is the exhast cloged some how? mabie a mouse climbed up their?
check compresion just for kicks...... I really think you are loosing power some were??? allthough I did have a motor run like that with a blocked exhAST before.......