Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

Boondocks101

Recruit
Joined
Sep 2, 2013
Messages
3
Hey all, 1st post and have a couple issues for a first summer boat owner.

To start by boat I have to have the throttle a little forward, turn and hold key on and slide handle back to straight neutral position and will start every time. Any answers what it is I need to do to remedy this?

2. Well just caught a gravel bar this weekend doing about 15mph, now I'm having a overheating issue and had to limp back to shore. I hooked up muffs to see if there is suction but not really sure where the water should be coming out of drive. I don't have an engine manual yet but trying to figure out what hoses to check on the engine to see if there is flow to the pump.

Any help would be much appreciated.

Thx and happy, safe travels
 

insttech1

Petty Officer 1st Class
Joined
Jun 26, 2011
Messages
340
Re: Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

Some carbs need to be primed by pumping throttle two-three times prior to starting, and then allowing to warmup for a few minutes.
(Some people will say it should start every time without priming, but even Holley Carbs says to pump a few times, and then warm up until choke is fully open. But warmup should be done at idle speed, and not revved up.)

As far as overheating, you have inhaled debris into the drive and/or cooling system.
http://forums.iboats.com/volvo-pent...have-technical-information-diyers-468654.html

The debris is either still in the drive, or made its ways all the way up to the pump housing, and may be all the way into the impeller, or possibly even further into the cooling system, restricting water flow.

You may be able to put something like a coat hanger or trimmer line up each of the ten or so entry points of the drive to see if muck is stuck in there, and if it will come down when broken free. Then you may have to remove the pump/impeller housing and see if it's full of junk and debris too, and check the condition of the impeller.

Disconnecting the main line that leads to the pump/impeller housing and letting it drain may also show you if there is junk in that line, and if there's no water that comes dumping out of it at all, then the debris is probably in the drive itself.

Also, after disconnecting the input line to the pump, and pointing it down into the bilge, you may be able to put muffs and high hose pressure onto the drive, and see if you can push water through the drive system, and just drain out the bilge by removing the hull drain plug. (This is after you insert something into the intake holes, so you can flush it out of the drive, and not into the impeller (and subsequently, the block/manifold, etc.....)

Water comes out in four jets on the lower unit of the drive (about 3/16" holes, two on each side of the drive, pointing straight down). You have to get on the ground to see them. The rest of the water will be pouring out behind the top of the drive, by the bellows.
 

Boondocks101

Recruit
Joined
Sep 2, 2013
Messages
3
Re: Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

Thanks for the info
As far as the cooling system, it got pretty hot by the time I limped back to shore so pretty sure impeller is toast, just wondering what other damage might have happened? I'm trying to find a engine manual to download or at least pictures to show me which hoses to check. I'm pretty sure I know where the pump and impeller is located.(behind big pulley at front of engine) Is it just the bolts on the front off the pulley you have to take off and impeller is behind it?

The throttle issue is after I prime it, it wont engage the starter unless I keep the throttle lever slightly forward, turn and hold key and slide throttle back to straight up and down. If I prime it and just leave it in the neutral position there is nothing. Then yesterday when I started it,while trying to see if I had suction I blew the ignition fuse twice. Is there a contact switch or something in the lever itself? Just seems weird especially after the blown fuses now.

Thanks again for the help,

Cheers
 

skydiveD30571

Lieutenant Junior Grade
Joined
Feb 13, 2012
Messages
1,042
Re: Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

We'll need a little more information on your engine than "4.3". Boat year doesn't always equal engine year, and there's many 4.3 models. The letters after 4.3, or full serial number, would be handy.

With that said, with any overheat situation especially when you run onto some shallow water, your first place to start is the impeller. You know where it is, and yes those little bolts come off and the impeller will come out. While you have the hoses removed, do as insttech said and either run water through the muffs, or backflush that line to make sure it is clear. It doesn't take long to ruin an impeller so don't be surprised if that's the case. If your impeller is in pieces, you'll have to go looking for them as they will clog up the cooling system just like dirt and mud.

Your next stop is the thermostat housing. Disconnect the hoses, pull the t-stat, and make sure all passages are clear. Once all hoses are clear and all impeller pieces are accounted for, replace the impeller, reconnect everything, and run it on muffs to make sure it is properly cooling.

Are you saying that turning the key when the throttle is in neutral does absolutely nothing? Your throttle has a shift safety circuit that prevents you from starting the boat when the throttle is in either forward or reverse gear. So normally, if you push the throttle forward like you currently do, nothing would happen when the key is turned. Since this isn't the case for you, and you have blown ignition fuses, I would bet there is something wrong with the shift safety circuit inside the throttle control. You can easily bypass this by finding the yellow/red wires coming to and leaving the throttle control and jumping them. Warning, do not leave it this way! This is for testing only! There are reasons your boat shouldn't start in gear so before you take it to the water, get this fixed correctly.
 

insttech1

Petty Officer 1st Class
Joined
Jun 26, 2011
Messages
340
Re: Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

Yeah I misunderstood your starting condition.
Your throttle wiring is messed up/disconnnected/shorting out.
You need to dis-assemble your throttle assembly and correct the problem, or replace bad parts.
Follow what skydive said to troubleshoot, and DO NOT DO NOT DO NOT leave it so boat starts in gear.

Some jackass did that this year to me when I gave him a jump on the lake....and nearly injured my daughter, as she almost fell into the water by his turning prop! (She was holding our boats together as it was getting rough.)

It was only AFTER that when his wife said "Oh, our boat won't start in neutral....":mad:
 

Boondocks101

Recruit
Joined
Sep 2, 2013
Messages
3
Re: Throttle issues with 98 four winns, 4.3 sx cobra, Over heating

We'll need a little more information on your engine than "4.3". Boat year doesn't always equal engine year, and there's many 4.3 models. The letters after 4.3, or full serial number, would be handy.

With that said, with any overheat situation especially when you run onto some shallow water, your first place to start is the impeller. You know where it is, and yes those little bolts come off and the impeller will come out. While you have the hoses removed, do as insttech said and either run water through the muffs, or backflush that line to make sure it is clear. It doesn't take long to ruin an impeller so don't be surprised if that's the case. If your impeller is in pieces, you'll have to go looking for them as they will clog up the cooling system just like dirt and mud.

Your next stop is the thermostat housing. Disconnect the hoses, pull the t-stat, and make sure all passages are clear. Once all hoses are clear and all impeller pieces are accounted for, replace the impeller, reconnect everything, and run it on muffs to make sure it is properly cooling.

Are you saying that turning the key when the throttle is in neutral does absolutely nothing? Your throttle has a shift safety circuit that prevents you from starting the boat when the throttle is in either forward or reverse gear. So normally, if you push the throttle forward like you currently do, nothing would happen when the key is turned. Since this isn't the case for you, and you have blown ignition fuses, I would bet there is something wrong with the shift safety circuit inside the throttle control. You can easily bypass this by finding the yellow/red wires coming to and leaving the throttle control and jumping them. Warning, do not leave it this way! This is for testing only! There are reasons your boat shouldn't start in gear so before you take it to the water, get this fixed correctly.

4.3L VOLVO PENTA SX COBRA

Boat Motor- T01312187 Model- 432BPBYC
DRIVE UNIT -T00825840 RATIO- 1.79

Thx for all the info
 
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