radiateu2

Ok I fixed my electrical problems replaced the coil and now the vattery is charging with the alternator I proudly rebuilt myself. From idle to a slight increase from idle I hear little popping sounds in the exhaust. My guess is I am a little lean or could it be something else? The power valve is good I checked it. I thought the problem was electrical in nature and to some degree I believe it was. So........I am wondering what the problem is now. My second guess is a failing mechanical fuel pump what do you guys think?

ede

i think you didn't do a very good job of describing the problem other than the poping sound. might be a good idea if you said what engine you have and induction system. what have you done or not done? tried any trouble shooting? is the tune up good? i'd suspect rich or timing maybe.

radiateu2

Ede,

I thought you might have read the sig for that info. Its a 305 with a Holley 600cfm vac secondaries. Older HEI ignition. When its running the engine like pulsates at idle high low high low. Think it might be the fuel pump. I disconnected the fuel pump from the carb and cranked the engine over and it took a while for the fuel to start pooring out and the fuel bowl was lower than when set. I originaly thought that it was an ignition problem related to my bad alternator. I rebuilt and replaced the alternator and replaced the ignition coil. To some degree the popping went away. Its not as frequent as it was only an occasional pop. The carb is as lean as I can adjust it.

Danno

Fuel starvation shows up in more cases than not as you accelerate-stumbling, hesitation. At idle, could be a carb issue. Also, a vacuum leak may be the cause. I would pull each plug and do a simple inspection. You may be able to isolate the problem that way. Local kid had a 305 with a similiar problem to yours and it turned out to be a leaky intake manifold gasket. Follow book procedures regarding base timing, carb adjustments, TPS if applicable then go on to vacuum lines gaskets etc. Try placing the ECM in the field service mode and observe the frequency of the SES light. It will indicate whether it's lean or not. You can also use a high impedence DVM and monitor the O2 sensor. Around .5 volts indicates proper F/A ratio.

ede

it's hard to know if the car in question is the one in the sig, i figure most people own or work on more than one. i have 2 camaros, my truck, suv, and mercades not counting my wifes car, step daughters car and my 2 kids cars and truck. as for the sig it doesn't show after you click reply, something that's in the softwear and not correctable.

radiateu2

Hey Danno,

No computer and just replaced the intake gaskets and the vac guage doesnt indicate a vacuum leak. I did notice that when I remove the fuel line it took sometime for fuel to pump up out of the hose. So I will replace the mechanical pump today.

Vader

Radiate,

You might be on to something. A mechanical pump should start delivering fuel within a couple of engine revs, if the check valves are any good.

And not that anyone needs to defend Ede, but I've been caught by the same thing. Sometimes, presuming the signature is the car in question can be wrong. Usually, that's my guess, but I've been burned, too. And the fact that the signatures disappear on the "Reply" screen doesn't help. I've had to open a second window to view the post as I reply just to see the signature details. I know, I'm just a whiner... WAAH!

Once you get a reliable fuel supply, you might want to check the float level as well. You should be able to remove the bowl level check plugs and set the level with the engine running. That's ONE nice feature Holley has over some other types.

A little pop in the exhaust can indicate a lean/hot chamber condition, or an excessively rich condition. With a rich mixture/late timing, you'd probably have other hints as well, and not just idle problems.

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Ede,

You don't let the wife drive the Mercedes, do you? There seems to be some bad precedents surrounding that mixture, at least in Texas.

radiateu2

Sorry for the confusion and the assumptions. I thought the sig was there all the time. I neverthought of to tell you what car I am working on since I only have one third gen. I can see the postion ede had taken. When I took the fuel line hose off the carb I was expecting some pressure and excess fuel but there was none. The fuel tank is full. When I cranked the car over no fuel.

Vader

Radiate,

So, did the new pump solve the problem?

radiateu2

Well Vader,

I got the pump today but, I had to work and on the weekends when I am not working I am sleeping most of the time. I will deffinately let you know though. I am curious to find out if it solves the problem. My first clue was when took the hose off and didnt get anything wet with fuel. Especially after just cranking it. After removing it and several 10-15 seconds sessions of cranking no fuel. I did check for air leaks and found none. I would assume if there was a leak I would have found some sign of fuel leak but did not. I think the fuel problem will solve some more of the issues I have been dealing with.

Ed

radiateu2

Well Vader,

The fuelpump solved the problems I was having with surging idle. I had a crankcase full of fuel. well atleast its all clean now lol.
No metal at all glad I didnt burn a bearing. Fixed the alternator problem too it was a blown fuse. All seems to be good for now.