'85 Mariner starting problems

[Br14n]

1985 mercury mariner s/n A926072 model 7050W 3 cylinder

short story:
Changed spark plugs, fuel lines good . flywheel engages and spins, it cranks but wont turn over and start, if that makes sense. tried it at idle, and throttled up out of gear, same result. Tried with manual choke, no go. Took panel off in front of carb and seem to be opening and closing in relation to throttle.

Was attempting to get the carburetor out to clean but can't find a good diagram.

Am I on the right track? Correct trouble shooting so far? Any ideas?

Long story: Been riding this boat since I can remember. Dad bought it new and just passed it down to me. Hasn't run much past 2 years. Batteries were bad, got a new starting battery. Motor wouldn't start. Cranks like it usually does when it starts, but just won't turn over and run. Checked spark plugs, didn't look good, changed them out. Thinking maybe the carb is clogged or the fuel pump isn't pumping. Tried to get to carb but wasn't confident without good diagram. Have the original manuals, but not a good visual guide. Took cover off to view carb, opens and closes in correlation to throttle.

Not, a mechanic, not afraid to get my hands dirty. Any help or shove in right direction is appreciated.


Thanks,

Brian

 

[carholme]

Re: '85 Mariner starting problems

Your s/n comes up as:

MARINER - ( 50 H.P. (1986 ))
Serial No: 0A926072 Model No: 7050726

Parts and Service Bulletin List for s/n 0A926072:

Search Results - Crowley Marine

In the parts list for the 3 cylinder. look at item 4 under FLYWHEEL, SWITCH BOX, IGNITION COIL, STATOR. Item 4 is the flywheel. Is this not turning when you try to start?

Gerry

 

[Br14n]

Re: '85 Mariner starting problems

I called a local dealer as I was having trouble finding the s/n online. He told me it was manufactured in 10/85. I guess it was an 86 model manufactured previous year?

Yes the flywheel engages and turns without a hitch. I'm not sure what it's called, but when I turn ignition to start there is a pinion gear(?) that raises up to the flywheel and engages and turns it. It is cranking just like it should, I believe, but it just won't fire up.


Brian

 

[carholme]

Re: '85 Mariner starting problems

OK, I was asking as your first post was a little confusing. Have you checked to see that you are getting spark and fuel? If so, have you tried shooting some premix directly into the engine>

The service manual you require is P/N 90-86135--5. here is one at an excellent price:

Mercury Mariner Outboards Service Manual Binder 45 50 60 70 4 Cyl 3 Cyl 90 86135 | eBay

In the meantime, here is a link to the condensed version of the Clymer manual to help you get started. Download it soonest to your computer as the link is short lived.

Small Engine Repair Reference Center Home: MARINER - MARINER 50, 60 AND 70 HP (3 CYL.).

Gerry

 

[Br14n]

Re: '85 Mariner starting problems

No I haven't. Not quite sure how to do that. I'm willing to try though with a little direction. I shot a video of what I got going now.

'86 Mariner 50hp - YouTube

If you watch and see when I prime the bulb a little gas leaks out from the fuel line at the connection to motor. I already pulled the fuel lines and they are clear and gunk free passing fuel through.

Thanks for the replies and links.



Brian

 

[Br14n]

Re: '85 Mariner starting problems

Well I had an exciting moment. Pulled out the spark plugs and put a couple drops of fuel in each one. Turned the key and it fired up for 1 complete second. Exciting to say the least.

That tells the novice in me that fuel is not getting to the plugs. That would mean the fuel lines/pump and or carburetor?

Where the fuel line connects to the engine, there is a female coupler. a hose from that goes to a small reservoir, which fills when i prime the bulb. A hose leaves there and goes into another component, not sure what it is, then another hose goes inside I'm assuming to the carburetor.

I did not inspect the hose going to the carburetor as I could not see where it connects. It appears, to get to the carburetor, I need to pull off more items.

It's getting dark and a little chilly outside so I'm done for the night. I will try to get the the carb tomorrow.

Do you guys think I'm on the right path?


Thanks,

Brian

 

[carholme]

Re: '85 Mariner starting problems

Brian;

You must get that fuel connection fixed as if you do get the engine running, it will start sucking air in at that spot. Where fuel can get out, air can get in.

The reservoir as you call it is probably the engine fuel pump. You can test it by disconnecting the line from the pump to the carb and with a drain can under the open hose, have someone crank the engine as ensure that you get a strong pulsations of fuel out of the line. This will tell you if the pump diaphragm/check valves are in good condition or not.

Gerry

 

[MH Hawker]

Re: '85 Mariner starting problems

Is the safety lanyard in place.

 

[Br14n]

Re: '85 Mariner starting problems

Is the safety lanyard in place.

no safety lanyard attached, but switch is in the run position.

 

[Br14n]

Re: '85 Mariner starting problems

Brian;

You must get that fuel connection fixed as if you do get the engine running, it will start sucking air in at that spot. Where fuel can get out, air can get in.

The reservoir as you call it is probably the engine fuel pump. You can test it by disconnecting the line from the pump to the carb and with a drain can under the open hose, have someone crank the engine as ensure that you get a strong pulsations of fuel out of the line. This will tell you if the pump diaphragm/check valves are in good condition or not.

Gerry

Today I got a little more in depth. Took the fuel lines off again. Took the fuel pump and diaphragm off. Never seen the diaphragm before so wasn't sure what I was looking at really. Took fuel filter out and cleaned it, not really dirty,

2 Hoses come off the fuel pump. One goes to the carburetors and other goes to back of the block. Took both those off and blasted compressed air through. One hose was clogged with what looked like salt water corrosion.

Then I attempted to get the carburetors off. I took off one screw each body and fuel poured out both. Almost like it was flooded. Got them removed from the block, could not get the choke cable off. At this point I was getting a little over my head and a little nervous I would not be able to get it all back on correctly. Scrapped it and put everything back on.

Thought I would give another shot with a few drops of fuel behind spark plugs again. Primed the bulb. Good news, this time it did not leak where it had previously. Turned over same as before and died. Tried again, same result. This was the first time it cranked on a second start.

After a few more attempts I put the run only throttle on and tried with the choke. Low and behold it started and ran. But as soon as back to neutral it would die. Couple more attempts with same result.

I then turned the priming screws on the carbs to fully closed, then back 1/4 turn. Couple more attempts and it would idle. It ran, and stayed running! Water was coming in and out of the engine. Everything seemed to be working.

The idle was a little off, didn't sound quite right. I adjusted the carbs a little bit and got it sounding much better. I let it run for about 10minutes without a hitch.


Could it have been the clogged line? Or maybe the diaphragm since it hadn't run in close to 2 years? I'm not exactly sure what I did, but I'm glad I did it.

Video
'86 mariner 50hp running - YouTube

Now that I got it running, winter is fast approaching here in the midwest. What things do I need to do to "winterize" it, since more than likely it won't be out much until springtime?

Thanks a bunch guys. This made my week.


Brian