No fuel pressure

[Harry B]

98 Malibu Sunsetter LX .  I was out surfing; 3 turns went well but 4th had no power then stopped completely.   Put a fuel pressure guage on the rail and got only 3 pounds of pressure.   Replaced the fuel pump.   Tested again and got 13 pounds of pressure.   Replaced the fuel pressure regulator.   Tested again and have no pressure.

Thinking maybe fuel pump relay but I can't find it.  Can someone send me a picture or tell me what/where to look for the relays?   There are  fuses behind the carburater on the same bracket as the ICM with 2 others marked fuel injector, fuel pump and something else.  I don't see relays though.

 

 

 

[justgary]

Is it a carb engine, or injected?  Can't be both. 

[Bozboat]

9 hours ago, Harry B said:

98 Malibu Sunsetter LX .  I was out surfing; 3 turns went well but 4th had no power then stopped completely.   Put a fuel pressure guage on the rail and got only 3 pounds of pressure.   Replaced the fuel pump.   Tested again and got 13 pounds of pressure.   Replaced the fuel pressure regulator.   Tested again and have no pressure.

Thinking maybe fuel pump relay but I can't find it.  Can someone send me a picture or tell me what/where to look for the relays?   There are  fuses behind the carburater on the same bracket as the ICM with 2 others marked fuel injector, fuel pump and something else.  I don't see relays though.

 

 

 

So you probably have FI.   The low fuel pressure indicates a bad fuel pump. High fuel pressure would indicate a bad fuel pressure regulator.  If the fuse or relay blew you should have no fuel pressure, particularly if you swapped out the fuel pump. All the residual pressure in the fuel rails would be released when you replaced the pump.   When you go to key on, can you hear the fuel pump prime?

have you changed fuel filters recently?

[justgary]

I agree that it sounds like the pump, but if the fuel lines are original they could be clogged.  If they are original, I would rig up a test fuel tank with good lines to try the motor before I changed the fuel pump. 

[Harry B]

found the problem yesterday; the fuel pick up line in the gas tank was in really bad shape with a split at the very top.   Therefore it was sucking air instead of gas.   Than gas line is very soft material and cracked in several places but the split at the top was the major issue.   I've tried to find a replacement locally with no luck as the hose needs to be very flexible and it is weighted so the pickup screen stays in the bottom of the tank.

 

Still interested in location of the relays for future reference

 

Thanks for the help.  Wish I had checked the tank pick up first as the fuel pump and the fuel pressure regulator are expensive particularly on this boat as the fuel pump is obsolete and requires a Conversion kit which makes it twice as expensive as the pump itself.

Edited July 24, 2020 by Harry B

[Bozboat]

Assuming your fuel lines are original, Now would be a good time to completely replace your rubber fuel lines. The old ones are not likely ethanol rated and at that age they are disintegrating.  They will eventually clog your filter and your pump.

[electricjohn]

Relays are usually under a metal box like cover that covers the ECM. Mine is on the center back of engine.

[Tracktor]

I just had similar issue which ahd me looking for a fuel pump for my 98 VLX.  I ordered a Electric Fuel Pump Carter P90043 of Ebay for $100 and will just plug the extra return line.  That seems to be simplest solution to the discontinued pumps on these.  That said, mine actually ended up being the canister style fuel filter after the pump.  While only a year old it had come apart internally and was restricting flow.  I replaced both fuel filters and checked screen just to be sure.  Runs like a top now & I have spare fuel pump for down the road...