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Skipper
08-09-2011, 11:50 AM
The boat runs fine for a few minutes. Then, when trying to pull a skier it bogs down and will not accellerate beyond 3000rpms. It is not over-heating.

1995 PS 190
Indmar TBI

Inspected the external fuel pump. It is clear of obstructions. Drained the fuel tank and all of the fuel lines. Blew out the fuel lines.

Any ideas?

Thanks in advance.

JimN
08-09-2011, 12:07 PM
The boat runs fine for a few minutes. Then, when trying to pull a skier it bogs down and will not accellerate beyond 3000rpms. It is not over-heating.

1995 PS 190
Indmar TBI

Inspected the external fuel pump. It is clear of obstructions. Drained the fuel tank and all of the fuel lines. Blew out the fuel lines.

Any ideas?

Thanks in advance.

If the ECM is at the side of the engine, pull the hose to the MAP sensor and make sure there's no liquid in it. Also, monitor the fuel pressure while it's running, under load. If you see a drop in pressure, make sure the anti-siphon valve/fuel shut-off, fuel pickup tube and vent/vent hose are clear. Also, open the gas cap to listen for vacuum.

BallBushing
08-09-2011, 01:06 PM
If you have one, check your transmission cooler inlet line for debris. Caused my bog down problem

Skipper
08-09-2011, 11:22 PM
If the ECM is at the side of the engine, pull the hose to the MAP sensor and make sure there's no liquid in it. Also, monitor the fuel pressure while it's running, under load. If you see a drop in pressure, make sure the anti-siphon valve/fuel shut-off, fuel pickup tube and vent/vent hose are clear. Also, open the gas cap to listen for vacuum.

Thanks Jim,
I know that the anti-siphon valve/fuel shut-off, fuel pickup tube and vent/vent hose are clear because I inspected, cleaned, and blew them out. How do I monitor the fuel pressure? Is there a guage to install in one of the lines? I ordered a new MAP sensor and TPS sensor. I'll inspect for liquid as soon as I can this week.

Skipper
08-09-2011, 11:25 PM
If you have one, check your transmission cooler inlet line for debris. Caused my bog down problem

Yeah, that was the first place I checked, well after about thirty minutes of trouble-shooting the perfect pass servo, cable, and throttle cable. I also have an inline water strainer before the transmission cooler. The strainer was clean and clear too. It is a puzzling and very doggone frustrating problem.

bret
08-10-2011, 07:59 AM
http://www.toolsource.com/fuel-pressure-tester-p-95303.html

or

http://www.sjdiscounttools.com/ta37650.html but you'll still need the gauge and hose.

JimN
08-10-2011, 11:13 AM
Thanks Jim,
I know that the anti-siphon valve/fuel shut-off, fuel pickup tube and vent/vent hose are clear because I inspected, cleaned, and blew them out. How do I monitor the fuel pressure? Is there a guage to install in one of the lines? I ordered a new MAP sensor and TPS sensor. I'll inspect for liquid as soon as I can this week.

If you have a paper clip or a cheap code scanner, you can check for codes. If you see no codes, it's not the MAP sensor or TPS. Look on the rigid fuel line to the throttle body for a black cap, about 1/2" diameter. That's a Shrader valve- looks just like a tire valve and that's where you would connect a fuel pressure gauge. Autozone and some other parts stores loan tools and hopefully, the ones they offer have a long enough hose that you can lay it on the floor so you (or someone else) can watch the gauge. You want to check pressure at Key ON/Engine OFF, idle, 2000 RPM and WOT. THIS HAS TO BE DONE on the water, not on the trailer. The pressure should be close to 30 pounds at all times, with small dips on hard acceleration and occasional small peaks.

It doesn't count if it's on a trailer and the symptom will rarely show up on the trailer. If it does bog at 3000 RPM, and it's in neutral, the inlet screen on the fuel pump needs to be removed for cleaning. The only cause of bogging at 3000 RPM I saw was clogged screens that looked clean. It can be clean on the visible side and still not be clean on the other side.

Skipper
08-10-2011, 11:29 AM
Okay, I know where the connector is for the fuel pressue guage. I will have to get back on the water to test the fuel pressure. I suppose it would be a good idea to pull the fuel pump off again and remove the screens to ensure that they are clear of obstructions.

You say that the only cause of bogging at 3000 rpm is clogged screens. That is a great clue, I will focus my efforts on the fuel pump.

Thanks again.

Skipper
08-10-2011, 11:33 AM
http://www.toolsource.com/fuel-pressure-tester-p-95303.html

or

http://www.sjdiscounttools.com/ta37650.html but you'll still need the gauge and hose.

Thanks. Looks like another specialty tool that I'll have to buy and use only once. Life was so great when the boat ran like a champ. All I had to worry about was keeping my hips square and finishing the turn so I would be early at the next ball. What a PAI!

JimN
08-10-2011, 12:26 PM
Okay, I know where the connector is for the fuel pressue guage. I will have to get back on the water to test the fuel pressure. I suppose it would be a good idea to pull the fuel pump off again and remove the screens to ensure that they are clear of obstructions.

You say that the only cause of bogging at 3000 rpm is clogged screens. That is a great clue, I will focus my efforts on the fuel pump.

Thanks again.

I don't know that it's the only cause but that's the main cause I saw. Occasionally, it would be a pinched fuel line, partially closed fuel shutoff valve or stuck anti-siphon device. It doesn't take much restriction to decrease the flow rate enough to limit performance.

Sometimes, the fuel tank resting on the fuel line causes the same thing. If this issue seems to be worse when the tank is full, look at that.

JimN
08-10-2011, 12:31 PM
Thanks. Looks like another specialty tool that I'll have to buy and use only once. Life was so great when the boat ran like a champ. All I had to worry about was keeping my hips square and finishing the turn so I would be early at the next ball. What a PAI!

Borrow one, or go to Harbor Freight, Sears, Autozone or Ace Hardware (they sell some Craftsman tools now). Google 'fuel pressure tester' and it will show sources in your area.

greeneng
08-10-2011, 04:38 PM
Well, that is what I have, and I have had this problem a few times. The first time I changed the fuel pump and that solved it. Then, I got brave and went inside the pump I took out and found the screen, deep inside it, clogged with gunk. After a couple of years, the problem happened again and I replaced the replacement with the original and that solved it. I now trade the fuel pump every couple of years, when the problem recurs, and clean the one I took out. Bet anything this is it. I believe the problem will only get worse, and recur more frequently, with Ethanol fuel.

Jim G.

Skipper
08-14-2011, 10:47 PM
Removed the fitting on the fuel pump inlet. Found that it was clogged with debris. Cleaned the screen and reinstalled the pump. Also, installed an inline fuel filter above the fuel cell. It appears that I have resolved the issue. Thank you for your input (to all).

Bassfooter
09-06-2011, 06:44 PM
Cleaning the little screen on the fuel pump inlet solved the bogging problem on our '94 PS190/Indmar 350 TBI. About the same time we started losing power around 2800 - 3000 RPM, I noticed a whine coming from the rear of the engine. This high-pitched whine was gone after cleaning that screen. It's like a new boat -- I wish I'd done this awhile ago. It is now on my list of annual maintenance items.

Be prepared for lots of gas getting out -- run your blower and have a fire extinguisher nearby, just in case. I used a clamp to hold the gas line from the tank closed.