94 Sport fuel?
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=48954
Printed Date: November-27-2024 at 4:16am
Topic: 94 Sport fuel?
Posted By: DougsdevilCC
Subject: 94 Sport fuel?
Date Posted: June-27-2020 at 1:46pm
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Baffled. 94 Sport 351. 490 hours. Hesitated around 2300 rpm and would not speed up anymore. Replaced fuel filter with a whole new mount and filter. Rebuilt Holly 4 barrel, wasn’t dirty. Replaced fuel filter again. Starts and runs good for the first few minutes and then hesitates again. Could it be something other than fuel issues? ------------- CCcruiser |
Replies:
Posted By: KENO
Date Posted: June-27-2020 at 2:40pm
Of course it could  Since 94 was one of the "ProTec" years, it would be good to know if you have the ProTec ignition system with 4 coil packs on the back of the engine and a funny looking sensor up front where the distributor normally goes...............or if it has a distributor up front in the normal spot. |
DougsdevilCC wrote:Posted By: DougsdevilCC
Date Posted: June-27-2020 at 5:28pm
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Yes, Protec ------------- CCcruiser |
Posted By: TRBenj
Date Posted: June-27-2020 at 5:43pm
| Sounds like limp mode. Better check your knock sensor, and oil/temp switches. Unplug one at a time to determine the offender. |
Posted By: Mpost
Date Posted: June-27-2020 at 5:53pm
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Does the check engine light come on when you turn the key to on before starting? If not I'd go with Tim's suggestions. If it does light but not when the problem is occuring, it could be and obstruction in the fuel pickup/anti-siphon valve. that gets sucked up after running for a bit. ?? ------------- 84 SN Sold 98 SN Lund Pro V 1975 Alumacraft |
Posted By: DougsdevilCC
Date Posted: June-27-2020 at 7:08pm
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Siphon valve is clean with good push back ------------- CCcruiser |
Posted By: DougsdevilCC
Date Posted: June-27-2020 at 7:17pm
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Light does come on when switch is turned on. Is the pick-up hard to get out of the tank? ------------- CCcruiser |
Posted By: DougsdevilCC
Date Posted: June-27-2020 at 9:50pm
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Pick up tube screen was clean ------------- CCcruiser |
Posted By: Jonny Quest
Date Posted: June-27-2020 at 10:35pm
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Tim hit it. Probably going into “limp” mode on ProTec...or ProTec is dying. JQ ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |
Posted By: KENO
Date Posted: June-28-2020 at 8:13am
I think a better description of what happens is needed here. Is it a steady misfire that goes away when you reduce speed and then it runs normal till you hit your 2300 rpm again? Like Mpost said, if it's going into "Limp Mode" the Red light should come on, since your Red light functions on startup. Does it stall like it's running out of gas? If I wanted to see if it was going into Limp Mode.I'd look at the diagram below and then disconnect the wire from the low oil pressure switch ( not the sending unit) and also the wire from the hi water temperature switch ( not the sending unit) , tape the ends so they can't ground against the engine block which would put you into Limp Mode and take the boat for a ride. Do the same with the knock sensor. If it still does the same thing, your sensors aren't putting it in Limp Mode since they're disconnected. Look at the diagram below to see the location of the ProTec switches. The oil pressure switch is in a "T" next to the oil pressure sending unit near the oil filter. The water temperature switch is at the left front of the intake manifold and the knock sensor is at the rear of the left cylinder head. There should be a Green wire attached to each sensor You'll probably have to enlarge the picture some  That still leaves the possibility that the ProTec system is on it's last legs though. Something else to consider is that it looks like you've gone through the fuel system with the exception of the fuel pump and the fuel line from the tank to the pump. If you've ruled out limp mode and think it's gas related, maybe it's time for a fuel pump replacement or rebuild and make sure your suction hose isn't restricted in any way. |
Posted By: DougsdevilCC
Date Posted: June-28-2020 at 10:11am
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Putting things together now, gas gauge shows 1/2 tank. When we pulled the pick up tube out not only was it clean but pretty dry. Filled the ole girl up and it ran good. We will see what happens over the next few days. Feel a little embarrassed if that is all it was... How can you tell if the gauge or sending unit for the gas is bad? ------------- CCcruiser |
Posted By: Jonny Quest
Date Posted: June-28-2020 at 12:12pm
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On these older boats, you may want to consider changing out both the sending unit and the fuel gauge. On my 1994, I pulled the fuel tank and replced both the sending unit in the tank and the fuel gauge at the dash. For me it was peace-of-mind. If you do change out the fuel sending unit, I recommend the "reed" style vs. the arm-and-float type. You simply measure the height of the fuel tank where the sender is mounted and subtract 1" to get the sender length. JQ ------------- Current 2003 Ski Nautique 206 Limited Previous 2001 Ski Nautique Open Bow 1994 Ski Nautique Open Bow Aqua skiing, ergo sum |