www.iFourWinns.com

Buddy of mine recently bought a 87' FW Sundowner. It has the Merc 165 (4 cylinder), Alpha one, closed cooling. He is out of town and his wife had the impeller changed and drive serviced to surprise him. Anyways, she wanted me to take it out for a shakedown cruise to make sure everything was working properly for when he returned. Boat started, idled, got on plane, and generally ran great, all gauges had good readings:

Oil pressure 65-70
Temp 130-140
Volts 12-13

Was cruising for about 20-30 minutes when I throttled down to idle, just putting along. Suddenly, oil pressure dropped to 0 and engine died. Crap. Drifted for a bit, opened engine cover, cranked for a bit, got it to start, but would only stay running if I gave it throttle. When I had it throttled up (in neutral), oil pressure would come back up to about 60psi. Listening to the engine, could detect no signs of an oil starved engine (ticking, pinging, knocking). As soon as I throttled down, oil pressure dropped, engine died. I repeated this several times until I gave up and got a tow into the ramp. I checked the oil level after getting it back to ramp, all good there.

So what could be the prob? Oil pump? Too thick of oil? Too thin? Clogged pickup? Does this year FW's have an engine protection system?

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

I'd guess a weak oil pressure sender. There were a few older mercs that had electric fuel pumps wired through the sender as a safeguard. My manual for that vintage merc is out on loan. I'll get it back today and see what I can find for you.

_________________
07 Azure AZ200,
Previous boat,
95 278 Vista,
And a lot of others.

Ontario, Canada

Ok, thanks!

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

I went to get the manual. He started giving me beer. I got loaded and forgot. My bad. As soon as I can get it, I'll see what I can find out for you.

_________________
07 Azure AZ200,
Previous boat,
95 278 Vista,
And a lot of others.

Ontario, Canada

Until wintersux recovers from too many Canadian cocktails ...anyone else got an idea what the prob could be?

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

Are you sure the engine dying is the result of the engine thinking oil pressure is dropping, or is the gauge just dropping along with the engine dying? It's a reach, but I've seen a battery with an intermittent internal short cause these symptoms.

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Mike
2005 Four Winns 230/240
VP 5.7GXi/DP
1998 F-150 XLT
Boat Pic

Hmmm, good question/thought. It took about 10 seconds for the gauge to go from normal reading to 0, then when it hit 0, kaput, so the two didn't really happen at the same time.

_________________

1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

Bump...

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

Another thought...could it be a failed shift interrupt switch that's shutting motor down....I've read about that happening to someone before on this forum. This is the switch that stalls the motor momentarily to permit alpha drive to shift into gear easily.

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http://i1339.photobucket.com/albums/o71 ... wqm355.jpg


08' H210SS
VP 5.7Gi

Update: Friends mechanic looked it over at his shop and couldn't get it to duplicate the problem I had on the water. However, he said the battery tests fine out of the boat, but once he hooks it up in the boat, it is only providing 4 volts. He discounted the oil sending unit/electric fuel pump idea that Wintersux had. He believes the problem is electrical, maybe a short.

Now, I'm only getting the info third hand, from mechanic to buddys wife, to me, so some things might be lost in translation, but something just doesn't sound right. Idea's/comments/beer?

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

Well... if there's any question at all about the battery, replace it first and make sure all battery connections are clean and solid. Any compromise in that area can cause all kinds of weirdness downstream.

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Mike
2005 Four Winns 230/240
VP 5.7GXi/DP
1998 F-150 XLT
Boat Pic

From what she told me, he did switch out the battery, same thing, only 4 volts. Soooo, looks like its "run down the connections" time, and like you say, make sure everything is clean and solid. My buddy returns in 8 days and he is looking forward to boatin....fingers crossed.

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

Oh, the 4V is with a new battery? Where is he testing and reading only 4V? If the battery tests at 12V out of the boat, then checking it at the battery won't be any different just because it's back in the boat - so he must be reading that 4V somewhere else. And even if battery cables are corroded, etc., the problem would most likely not be that the voltage would read low - they just wouldn't be able to pass enough current to run things (which is not what he's saying is happening). I'm with you, some information is getting lost in the translation, or something...

The "4V question" aside, my next suspect would be the ignition coil. They can be fine when cool but fail when they heat up.

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Mike
2005 Four Winns 230/240
VP 5.7GXi/DP
1998 F-150 XLT
Boat Pic

Ya know, you saying that jogged my memory. My neighbor has the exact same engine/drive in his 87' Imperial cuddy, and I can remember helping him earlier this year run down a starting problem. Turned out to be the coil. I will pass the info along, hopefully that is the culprit.

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1996 205 Sundowner DLX
5.0FL Volvo SX Cobra
Tow Veh: 2012 Nissan Frontier Pro-4X

I got my manual back. Is this engine EFI?

_________________
07 Azure AZ200,
Previous boat,
95 278 Vista,
And a lot of others.

Ontario, Canada