1980 merc 40 not charging/wont idle/water around cowl

[YN2(SS)]

After purchase of the boat motor, found two burnt/disintegrated wires coming out of the switch box assembly (white and red) and we repaired those. Also found one loose wire coming from the stator and a loose connector on a unit, so we installed it. Suspect this was the right place to put it, but don't know. We ran it a few weeks ago with a cuff and it was not pumping water, so we have replaced the water pump/impeller. Also removed gas and water from the gas tank, installed with fresh and removed the water from the filter. Have the following problems. Any thoughts?

1) Put it in the lake, prior to starting, checked voltage of battery at posts, all wires connected, 12.3, with engine running, regardless of RPM, 11.9. Suspect switch box assembly, will try to check that per the SELOC manual as well as Regulator/Rectifier and Stator. Also, RPM gauge doesn't work. Any other ideas?

2) Started motor, a nice stream of water out the back, then after a while less water out the back and more dripping out of the bottom of the cowling. Did I blow a gasket between the powerhead and the lower unit?

3) QuickSilver Remote Controls. Engine wouldn't idle, tricked it into gear to get it going(throttled back from throttle only operations, then clicked it forward into gear quickly), ran it for about 30 mins. Pulled hard, ran/sounded nice. Still wouldn't idle. Should I just rebuild the card and fuel pump?

Thanks in advance for your time and comments!

 

[mmf]

Re: 1980 merc 40 not charging/wont idle/water around cowl

rectifier is probably shot and or shorted, if shorted, it can lower the output voltages from the stator and cause weak ignition which can cause no idle or erratic operation. Disconnect rectifier wires from stator and check for voltage coming from stator while cranking, (will vary at different rpm) if ok, then insulate them so not to short out to anything and see if it will idle, if it will, take your ohmmeter and check your rectifier block for open or shorted condition. Should read about 1.5Kohms one way and infinity the other way when checking from one AC terminal to the positive side and the same from the other AC side to the negative (ground) side on the rectifier.

 

[YN2(SS)]

Re: 1980 merc 40 not charging/wont idle/water around cowl

1) Replaced the rectifier. Now,12.45 V at the battery before start, 13.0 V when engine is just above idle. Now, my tach is working but bouncing up and down. Will try to post a video later. Any thoughts?

2) Rebuilt the carb and fuel pump to try to cure idle problems. It will mostly idle now but needs a little more work. Replaced all fuel lines inside the cowling and all hose on or running to or from the fuel pump and carb. Found a hose that comes from the port lower aft side of the engine to the fuel pump that was half torn off. This is a water line. Replace and cured the water inside the cowling problem. Will try to post a video though. I have water spraying around the outside of the engine in the area where I believe the powerhead mates to the lower unit.

3) Rebuilt the carb and fuel pump and runs better but still needs a little help. Want to rebuild the remote control to ensure smooth and correct operation and adjust friction.

Thanks MMF for your help. I think I understood your test of the rectifier. It seemed it test bad, and was weeping black tar. The new rectifier did not have the same test results. It charges now!

 

[YN2(SS)]

Re: 1980 merc 40 not charging/wont idle/water around cowl

Now the remaining water leak problem I have is this. There is a significant amount of water spraying out the bottom of the cowling but it is not from the hose I was talking about earlier. Any thoughts?

http://www.youtube.com/watch?v=JVaJGzzPR-A

 

[mmf]

Re: 1980 merc 40 not charging/wont idle/water around cowl

I'll bet one of your hoses that come up to the 2 fittings at the fuel pump are leaking, rotted or both. Also dirt daubers love to make nests in pee hole tubes, rod it out with weedeater line while it is running on muffs or in a barrel.
On mine dirt daubers crawled up the hose and completely stopped up the copper line that goes around a loop inside the fuel pump. I had to remove fuel pump and rod out the tube with a steel flexible line to get it unstopped. Glad I did too because the fuel pump diaphram was really dried up too and it would not have been long it would be cracked. I also change my impeller every season because they get set and don't pump as good with age.

 

[YN2(SS)]

Re: 1980 merc 40 not charging/wont idle/water around cowl

I did have a broken line to the fuel pump and water was leaking in the cowl. Got that fixed. The remaining leak is the one above. How much water should I see coming out of the holes in the back of the top of the lower unit? I like where you are going with the mud daubers. I'm bout ready to lift the powerhead off of the lower unit to see if there are any gaskets leaking there.

 

[YN2(SS)]

Re: 1980 merc 40 not charging/wont idle/water around cowl

As a follow up, the water leak is coming from the rubber covered bolts that mount the midsection to the transom mount. the rubber is torn.

Tach problem still exists. Havent found the problem yet.