1996 Mariner 75 horse Reed issue?

[EMC 1810SS]

I have a 96 Mariner that I just rebuilt the carbs and set base timing. Before the build I know I had cylinder #2 but it was intermittent. I know the carbs are good, and its getting fuel, I think its getting spark because the timing light flashes in #2 and compression is right at 125 in all three holes.

The reason I am thinking reed plate issues:
1. There is excessive fuel pooling in the bottom of the cowl.
2. I had a backfire through the carb, which I didn't think could happen with a reed plate.
3. You can see the fuel mix is spitting back out of the #2 carb when looking at the airbox cover.

At this point basically #2 cyclinder is dead.

My first question, Does this sound like a reed issue? Is there any way to confirm without pulling it apart?

The Second Question, I could get a used reed plate for maybe $30, a new reed plate (Just one) for around $90 or a full set of boyesen reeds for around $120. What would you recomend?

Should I replace all of them at once? or just the one that I suspect it bad?

Thank you!

 

[CharlieB]

Re: 1996 Mariner 75 horse Reed issue?

1. Pull the carbs use a flashlight and inspect the reeds. IF any are cracked, chipped, or warped more than a 32nd of an inch then think about replacing. Boysen are good, and if a plastic reed ever breaks it will pass thru the cyl with minimal damage to the piston.

2. Spark test with the throttle cable disconnected and move throughout its travel so as to check trigger wires while flexing. A broken trigger wire can lose spark during movement.

 

[EMC 1810SS]

Re: 1996 Mariner 75 horse Reed issue?

Thank you! I spoke with Chris Carson today and pretty much nailed it down to bad reeds in the #2 hole. Fuel spitting back out of the one carb pretty much nailed it. He has a full set of glass Reeds for $65. That plus gaskets we are talking about 90 bucks.

 

[EMC 1810SS]

Re: 1996 Mariner 75 horse Reed issue?

Well this is what I found. No wonder it wouldn't fire! BTW they look like the two piece boyesens to me....

 

[Maxz695]

Re: 1996 Mariner 75 horse Reed issue?

Yep that would cause the pooling and the backfire. Good thing it didn,t break off or there would have been serious internal damage

 

[Faztbullet]

Re: 1996 Mariner 75 horse Reed issue?

Yep ...that them junky Boyesens as they only last 2-5 years depending on motor usage. If the carbs are not set up correctly one lean pop will take em out.

Good thing it didn,t break off or there would have been serious internal damage

Max ...these are fiberglass reeds designed that if ingested will not damage internals....

 

[Maxz695]

Re: 1996 Mariner 75 horse Reed issue?

TY for that info They look alot like the 40 HP I had but they where metal View attachment 176318. Are the reed stops on the opposite side?Also I don,t think there 2 peice as there are only 9 pedals

 

[Faztbullet]

Re: 1996 Mariner 75 horse Reed issue?

Actually 18 as there is 9 thin secondary reeds on top of 9 thick primary on bottom. Here is link to look at so you better understand.....
BOYESEN REED KITS for MERCURY 2, 3, & 4 CYLINDER OUTBOARDS --MASTERTECH MARINE--

 

[Maxz695]

Re: 1996 Mariner 75 horse Reed issue?

what do you suggest would cause the failue? Heat, Debris? Just wear and tear? I have seen fiberglass reeds and from what I heard they where supossed to be better but after this post I would never use them.

 

[EMC 1810SS]

Re: 1996 Mariner 75 horse Reed issue?

what do you suggest would cause the failue? Heat, Debris? Just wear and tear? I have seen fiberglass reeds and from what I heard they where supossed to be better but after this post I would never use them.

My fuel pump started going bad and I had a lean backfire. It looks like it pushed the one reed through and got stuck. The Boysens look decent, but I am puting Carson reeds back in.