Fuel pump diaphram

[HTG]

How often does this have to be changed? I just changed mine about three seasons ago and found out it may have to changed again. Is that normal? Its a 1984 35hp Mercury.

 

[racerone]

No----Not normal.-----What is your motor doing / not doing?

 

[silverbul]

When in doubt. change it out.

 

[flashback]

No----Not normal.-----What is your motor doing / not doing?

Might be normal for chinesim parts...

 

[roscoe]

Might be normal for chinesim parts...

If you use mercury, sierra, or quicksilver parts, they should last

No name eBay or Amazon parts may fail quickly.

 

[HTG]

This is the thread i posted just last week.
"This engine is cutting out or isn't able to suck the gas in when I put it in full throtle. I can put in full throtle and it will go about 30 yards and it will suck the gas out of the hose and just cuts out. Does anyone know what needs to be adjusted or fixed with this problem? I've tracked this down to the fuel line before but this time its happening to often so I think its something else, but I'm not sure what needs to be fixed. Anyone been down this road before?

The one thing that may have caused it was a kink in the gas line. When it first started happening that was the reason. So that kink may have caused it to rupture. I quess I will change it though but I have to take it out and check it one more time.

 

[flashback]

Yep,, a kink in the fuel line ain't good for the flow..

 

[HTG]

I took it out again yesterday. Now at full throtle its fluctuating or going up and down about 5 mph. Does this sound like the fuel pump diaphram or something else?

 

[Chris1956]

Sounds like a fuel restriction. It could be a clogged fuel filter, clogged fuel line antisiphon valve, clogged fuel tank vent, clogged fuel pickup screen, or something wrong with the fuel line or fittings leaking air.

Merc back drag carbs often have a screen in the fuel elbow that feeds the carbs. It can clog but doesn't do so very often. Not sure if you have those carbs.

 

[flashback]

How fresh is the fuel? Water in it can cause a fluctuating throttle..

 

[HTG]

Can anyone tell me how to check the fuel filter? I'm using fresh fuel. I did check the fuel line and everything else and I don't think thats the culpret. I've changed the fuel diapham once before and just want to make sure thats the problem or problem area before go in for surgery. Thanks

 

[Chris1956]

Sure, remove old fuel filter. Toss in trash. Install new fuel filter.

 

[HTG]

Thanks, youtube has a lot of videos on how to do it which helped. I think I will switch the fuel filters and check fuel line to find out if anything is in it. Hopefully that will help. If anyone knows of anything else on this subject please post. I'm wondering which online shop may have the correct fuel filter? Anyone have any suggestion on where to find to correct fuel filter?

 

[brodmann]

I just Googled "1984 35 HP Mercury Outboard" Just slightly over 4,000,000 results. Time to shop!! Not hard to find parts online.

 

[HTG]

Its a 1984 Mercury 35hp 2 stroke, the serial number is 6578665. In case anyone can find the correct part.

 

[topgun3690]

In case anyone can find the correct part.

Have you tried googling Mercury, Quicksilver, marineengine.com, Crowley Marine, boats.net, ebay(with part#) to name a few.....with the year, make, HP, and serial number you should be able to find it with no problem. It aint that hard.....

 

[racerone]

Agreed----This is easy.

 

[HTG]

I used marineengine.com for the first time. It was easy and fast. Thanks

 

[topgun3690]

I used marineengine.com for the first time. It was easy and fast. Thanks

There ya go.....you can also use them to get part numbers....with their parts diagrams.....then look on ebay for cheaper prices or for discontinued parts sold as NOS (new old stock).