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peterb
08-01-2006, 11:40 PM
I have an 86 with a 351 and a 4160 carb. Prior to rebuilding the carb I had a problem with stalling at idle once warm and at tubing speed, it would drop out and stall then not be able to start.

I rebuilt the carb and seemed to correct the warm engine stall in idle. But, I still have a problem. Around 30-35 mph the engine will stall out after running for a few hundred feet.

Today we tried it with the engine cover off and the flame arrestor off. As it started to stall out, we hit it with some starting fluid and it came back to life then stalled out again. We kept it running with starting fluid which points towards starving for fuel.

To rule out a plugged airvent on the fuel tank (as someone suggested), we drove with the gas cap off and still had the problem.

So, I guess at this point, because it happened before and after the carb rebuild, it points to something else... maybe the mechanical fuel pump?

Prior to using the boat this year, we drained the fuel tank and cleaned it out as well as putting in a new fuel/water seperator filter element. Is there another filter I am missing?

Is there a way to "test" the fuel pump before I buy a new one.

Any other suggestions?

madison
08-02-2006, 12:54 AM
I have an 86 with a 351 and a 4160 carb. Prior to rebuilding the carb I had a problem with stalling at idle once warm and at tubing speed, it would drop out and stall then not be able to start.

I rebuilt the carb and seemed to correct the warm engine stall in idle. But, I still have a problem. Around 30-35 mph the engine will stall out after running for a few hundred feet.

Today we tried it with the engine cover off and the flame arrestor off. As it started to stall out, we hit it with some starting fluid and it came back to life then stalled out again. We kept it running with starting fluid which points towards starving for fuel.

To rule out a plugged airvent on the fuel tank (as someone suggested), we drove with the gas cap off and still had the problem.

So, I guess at this point, because it happened before and after the carb rebuild, it points to something else... maybe the mechanical fuel pump?

Prior to using the boat this year, we drained the fuel tank and cleaned it out as well as putting in a new fuel/water seperator filter element. Is there another filter I am missing?

Is there a way to "test" the fuel pump before I buy a new one.

Any other suggestions?

so it runs good until the secondaries kick in??? im having similar issues with my 89 ps190.. not as extreme, but thinking I am going to have to replace the carb

Jesus_Freak
08-02-2006, 02:31 AM
Extra filters: Check the carb fuel inlet port, as well as the rubber hose leading from your tank to the inlet of your fuel pump.

Fuel pump: Disconnect the fuel tubing downstream of the pump and check the discharge pressure with a gauge.

peterb
08-02-2006, 09:31 AM
Watching in the carb, this is before the secondaries kick in.

Before the inlet on the fuel pump is the fuel/water seperator/filter. We replaced that element.

Didn't see a filter on the inlet port of the carb when we rebuilt it.

If I disconnect the fuel line from the pump and check the pressure, then I assume that is just cranking because there won't be any fuel in the engine to fire (it's a mechanical pump)? What should the pressure be? Where can I find a gauge?

BrianS
08-02-2006, 05:24 PM
I just solved a similar problem with my '93. Here is a link to the thread with some tips and pictures.

Link (http://www.tmcowners.com/teamtalk/showthread.php?t=9783)

Also, if you still have the original mechanical fuel pump there is a filter element inside there. I replaced my fuel pump trying to solve my problem and the filter element in the old pump looked pretty bad. The replacement pump from Skidim does not have a filter inside.