Engine quits when reving up

I just bought a a used boat and I am new to outboard motors. I have an 1989 85hp force outboard that was rebuild by the previous owner last spring. I took the boat out on the water and it ran fine for about 2 hours when it died on me. I manage to start the motor up again but it won't rev above 1800rpm. The motor will quit when I try to throttle it up. What could be wrong with the motor? Could it be the oil mixture? Do I have something stuck in the carb? I also notices that the intake manifold does not have a filter. Do outboards have air filters? I am planing to take apart the carb to clean it. Is there a way to troble shoot it before taking the carbs apart?<br /><br />Thanks<br /><br />PC

Re: Engine quits when reving up

There is not an air filter on that engine, there should be an air box. The air box helps keep debri out of the carbs and quiets the engine.<br /><br />Sounds like it could be a fuel pump problem. Should be able to get a fuel pump rebuild kit from NAPA.

Re: Engine quits when reving up

When I first got my 86 bayliner with 85 force it would run fine in the driveway but when it was in the water it wouldnt get above idle without stalling. Some people on here told me to try and run it with the engine hood off and it ran fine. Turns out the exhaust boot was leaking and when its under water the only place for the exhaust gases to go was back into the engine and it choked itself. Maybe this is something that you should check for. Mine turned out to be dryrotted a little by the clamp and all I had to do was loosten the clamp and force the boot on a little more then tighten it back down.

Re: Engine quits when reving up

If you work on the carbs do it one carb at a time. Link and sync can be tough without a manual. Check your spark plug tips to verify even burn or residue on the tips. A clean spark plug tip can be a trouble cylinder. If plugs check out okay do the fuel pump first. The kit from NAPA is 18-7806 priced at about 10 dollars. Here is the parts blow up for your fuel pump<br /> fuel pump Start by just replacing the diaphram and the pump gasket parts 15 and 16. The pump can be done in about half an hour and is pretty much a no brainer. If you do dive into the carbs try not to adjust anything other then replacing the gaskets, seat and the needle valve. Verify the float is adjusted correctly and count the turns on the idle adjust screw clockwise till it lightly seats. This is where you will want to set it after you replace the spring on the mixture screw. The carb rebuild kit from napa is 18-7037 also from NAPA for about 15 bucks a kit. You will need one for each carb. Do not interchange parts from your carbs.

Re: Engine quits when reving up

Thanks for all your comments. I think it must be the fuel pump. I am using a metal 6 gallon gas container and forgot to vent it. I remembered only after cruising around for a while. About 5 minutes after I released the screw for the vent, The boat started to choke when I'm reving up. Does this make sense? Is it likely that the pressure build up from the gas tank caused the fuel pump to fail?

Re: Engine quits when reving up

I have a Chrysler 1974 75 hp three cylinder with the same problem- I also ran it by accident without the vent open for thirty minutes then it died and would only start with the cover off. Does that mean I need to rebuild the fuel pump? And if so where to get the parts?

Re: Engine quits when reving up

Gab999. Your fuel pump rebuild kit is the same as mentioned above. It is a 18-7806. YOu can get one from NAPA for about 10 bucks. Just concern yourself eith the diaphram, fuel pump gasket and maybe the screen and sediment bowl gasket. Dont mess with the fuel seat gaskets that come with the kit. The press fit seats are a bear to get out without breaking them and the gaskets provided with the rebuild kit probably wont fit anyways.

Re: Engine quits when reving up

I just checked the diaphram and fuel pump yesterday. The diaphram and gasket seems fine. I connected the gas line directly to the carbs but the problem is still not solved. I am ruling out the fuel pump. What else could be wrong with it? The spark plugs are pretty wet, coated with black oil when I took them apart. All three spark plugs look similar. Would a cloged jet in the carb cause the same problem. If I am able to start it and idle, would that mean the main jet is clogged? Would one carb failure cause the whole engine to stall when reving up? All three main jets clogging at once is pretty rare.

Re: Engine quits when reving up

pc, please check for spark and compression on all three cylinders.

Re: Engine quits when reving up

With your fuel pump I would still recommend rebuilding it-- the kit is cheap and it's easy to do-- When I took mine apart the gasket and diaphram seemed fine, but it was stretched out somewhat -- I rebult it in five mintes and it fixed my (similiar) problem-- When I ran it unvented the pressure must have built up and stretched out that diaphram-- All you have to do is remove the screw that holds the sediment bowl, then take off the other six screws and the front half pulls off-- pull off old gasket and diaphram, then put new ones back in, bolt it back up and reconnect the sediment bowl--