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No power at WOT

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lee42lee

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I just installed a new 5.7 lon

I just installed a new 5.7 long block in my boat and have a problem. I put the boat in the water today and it was real sluggish. The boat took forever to get on plane and it was popping back through the carb and could only get 3500 rpm and if I went wide open it would bog until I put it back at 3/4 throttle then it would pick back up. I bumped the time up and it helped a lot but I still couldn't go over 3/4 throttle. I replaced my old carb with a 4 barrel Rochester Quadrajet when I changed the motor. Could it be the Carb and if so what do I need to do? Since it helped when I bumped up the time could it not be advancing the time? Thanks for any help and sorry for the long post.

Lee
Just so you know this is a 5.7GL Volvo.
 
"Check that the firing order i

"Check that the firing order is correct, you could have a couple of spark plug wires swapped. Also, check that the ignition timing is correct.

I assume that the distributor rotor, cap and ignition wires are in good order. If all looks OK and you have concerns about the distributor, you may consider sending the it to a shop wehere they can put it on a test machine and check the advance curve.

Regarding the carb, is it new/rebuilt/tested? If it has automatic choke, make sure it is working; if it remains closed, the boat will not be able to plane. Also, make sure that the secondaries are opening whent hey should. Check the Seloc manual for correct carb setting."
 
"Electric fuel pump? Check the

"Electric fuel pump? Check the pressure. Make sure the timing it right, all power and grounds are clean and tight, the connections on the coil and distributor are tight and in good condition, no vacuum leaks and the compression is good."
 
A new 5.7 long block.....

I

A new 5.7 long block.....

Is it possible that some of the rockers were not properly adjusted to give the right valve clearance?
 
"Jim,
It is a mechanical fu

"Jim,
It is a mechanical fuel pump.

El,
It is a rebuilt carb.

Guys let me give a little more info. When I first got the boat (with 2 barrel) it ran fine but I did notice that it I couldn't go wot but wasn't as bad as this. All I had to do was barley bump it off wot but now I have to go all the way down to 3/4 throttle. It kind of seems to me like fuel starvation since it worse now with the 4 barrel but I guess it could not be advancing the time. I am going to put the timming light on it Tuesday and check it. I will post back with the results."
 
"Your distributor has mechanic

"Your distributor has mechanical advance? If the mechanism hasn't been checked or maintained lately, I would look at that. If it's vacuum advance, I would do a vacuum test to make sure there's no problem. If it's too lean, I would look at the fuel pressure.

El Pescador- isn't the mechanical pump supposed to deliver about 8 lbs of pressure?"
 
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