1985 85 hp fuel problems

[ammermanfam]

Hello my name is John and I am new to the board. I jave an 1985 85 force that was running fine till I changed the primer bulb. First trip out as soon as I got on plane the engine would die. I reprimered the engine and it fired right up. Kept happenin for 10 minutes then ran fine the rest of the day. A few trips later I noticed the fuel lines between the carbs were wet with gas so changed them. Now the problem is back . I changed the diaphram. Yesterday on the water it would Idle along just fine. When I tried to get on plane it would bog down and die. I tried having my buddy hold the steering wheel while I would squeeze the bulb and the boat would stay running strong. It even ran fine most of the day after that. On way back to the ramp I noticed every time the nose dived after hitting a wake the motor would pause for a split second. Just wondering which direction to go from here? I alao end up with a little fresh fuel on the outside of the bowls and intake. Could this strictly be a stuck or sticking float Issue??? Thank you in advance JOHN

 

[john from md]

Re: 1985 85 hp fuel problems

More likely sticking check valves in your fuel pump. You said you can keep the engine running by pumping the ball and that it starts up right away after it shuts off. Those symptoms are usually associated with sticking check valves. I have seen this starting to happen ever since ethanol came around. The new check valves have the center button made from a different material. Maybe the new stuff is ethanol resistant.

Pull the fuel pump housing off and gently push in on the button in the center of the vavles. You can only check two as one is installed in the opposite direction. If either check valve sticks, change all three. They only cost $5 each.

Regards,

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

Thank you for your reply. Are those valves available online anywhere you recommend, that you know of?? Dont mind doin the foot work just wondering if you knew. I assumed they would come with pump rebuild kit I purchased from this site but they did not. John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

Pulled the fuel pump housing and sure enough the middle check valve is stuck. Found some online for 5 bucks each plus shipping . Will update after the repair. Thanks again. John

 

[john from md]

Re: 1985 85 hp fuel problems

Like I said, if one is sticking, I would change them all. I'm curious, does yours have an amber colored plastic for the poppet piece?

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

Any recommendations how to remove the outlet check valve? I cannot get behind it because the the fitting is on the side. I do not want to mess up the housing by prying to much. Thank You. John

 

[john from md]

Re: 1985 85 hp fuel problems

For the one valve, I had to make a slap hammer using an L shaped insert. You put the L through the center and catch the back end. Before using the slap hammer, I weakened the wall with a Dremal tool. The new one just presses in using a standard socket.

I guess if you were careful enough, you could cut the valve out totally with the dremel tool.

Regards,

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

Finally got he boat out after replacing the check valves. Iwas a little nervous it was going to fix it, But as I applied the throttle it hopped right up and kept going. Thank You so much John From md. Next question is Is that it starts fine in the driveway but Is harder to start on the ramp and after long runs. I know that it is carbeuration Just wondering which way to head??? John

 

[john from md]

Re: 1985 85 hp fuel problems

Before you go changing anything, make sure you are starting it correctly.

Cold start
1. Pump ball a few times (doesn't have to get rock hard)
2. Put throttle in fast idle position.
3. Push in key (to choke) and turn to start.
Should start within a revolution or two.

Warm start
1. If just shut down, leave trottle at idle, bump key without choke. Should start right up.
2. If sitting for a while, place throttle in fast idle and turn key without using choke.

While these engines need a warm up on the first start of the day, it is easy to flood them when starting warm.

If you are already doing this stuff, let me know and I will give you carb tuning instructions.

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

I usaully dont use the fast idle while restarting after a while. I wont be able to get out for a couple more weeks. Will write back then and let you know if that helps my problem. Thank You. John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

I got lucky and was able to get out sunday. I followed your instructions and it ran fine until the end of the day. The last hour of the day It would barely start at fast idle. I would have to turn it over and wait for it to just start then quickly slap it into gear before it died. It semmed like the idle setiing was out of wack. I did have a small encounter with something underwater but at low rpm and no prop lower unit damage. Started it in the driveway this morning and it ran fine. John

 

[john from md]

Re: 1985 85 hp fuel problems

Check the orifice that is under the number one carb. It connects by hose to the intake manifold. You have to screw it out and blow it clear with air as it has a real fine hole in it. If it is clogged, you will have idle problems as it can't suck the excess fuel that gets spit into the manifold during shutdown.

Normally, after you start, this excess oil is sucked out within the first minute thereby keeping the engine from being too rich. If the orifice is clogged, the engine can't stabilize and stalls out.

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

I checked both sides both fittings and neither was obstructed as well as the hose.? John

 

[john from md]

Re: 1985 85 hp fuel problems

Maybe you should pull your plugs and see it they are carboned up. Since you say this was at the end of the day, maybe your carbs are a tad rich and carboned up the plugs. These engines tend to foul easily as it is.

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

I just pulled the plugs. they have some build up on them maybe 25% on the edges. Theyhave been used only for three trips. They were wet from when I started it 4 hours ago. Is that normal???John

 

[john from md]

Re: 1985 85 hp fuel problems

Sounds like they are normal. Next time you are out, when you are starting the engine during short shutdowns try it without using fast idle. Also, try to gather more info like, is the ball hard when you try starting, does it kick back, does it not fire at all etc.

John

 

[ammermanfam]

Re: 1985 85 hp fuel problems

Will do, although in a couple weeks. Your a wealth of knowledge on this forum and a valuable asset. Thank You for your time. John

 

[john from md]

Re: 1985 85 hp fuel problems

Just helping out in a field I know about. Pass it on whenever you can.

John

 

[intel*outside]

Re: 1985 85 hp fuel problems

Hi John and John!

I was having the same exact problem on a 1987 1700br capri w/ the 85 hp force and replaced the check valves, diaphragm, and gaskets after reading this post. It used to get up to 30+ or so and ran like a champ until the motor was starved for fuel. After a few pumps on the primer bulb, it would get up for a bit and then die again - also had the same problem with the motor cutting out when planing. After the replacement, the boat now peaks out at about 5-7mph and additional throttle kills the motor. I made sure to clean the parts well before reassembly, filled up the tank w/ 5gal of gas mixed @ 50:1, and was quite disappointed when I got out on the water. Seafoam and pumping more gas via the primer had no effect. Do you think something could be causing a blockage somewhere and preventing a cylinder from getting fuel and firing? I noticed that the top of one of the plugs was a bit rusty on the tip between the wire, but I wouldn't think that this would cause such a substantial loss of power. It had only been sitting for 2 weeks before the attempted fix.

Thanks!
-John B.

 

[john from md]

Re: 1985 85 hp fuel problems

John B.

1. Are you sure you put the check valves in the right direction? If you didn't, the fuel pump will not be able to supply fuel to the carbs at the volume it needs.
2. Do you have an internal tank? If so, go buy a three gallon tank and hook up the engine to feed from it. Then try it. Phase separation of Gasohol is playing havoc with intenal tanks because of the issues with the alcohol.

John