mercury fuel pump problems

[chestercheese]

hello again

i've got my self a lovely merc 80hp outboard
the man who gave it to me said that theres a problem with the pump?
he took it a part to clean? just a maintance cleaning freak, and it would'nt start after that, so he gave me the outboard,
i've taking the fuel pump off and seen that both the diaphragms are facing the same way?? am i right in saying that they should face different directions? cos when priming, the fuel wont get though the pump, i,e they are both closed?
i cant seem to find any photos of which way they should face?
any help would be great
thanks dan

 

[Barnacle_Bill]

Re: mercury fuel pump problems

What year and model is it?

 

[chestercheese]

Re: mercury fuel pump problems

hello
i think its the mercury thunder bolt, about 1980 ish? hope this helps?
cheers dan

 

[SeaKaye12]

Re: mercury fuel pump problems

Can you provide a serial number of the engine? There were a couple of different pump designs...

Or; a picture of the pump...

Chuck

 

[chestercheese]

Re: mercury fuel pump problems

hello
i will do in abit,
also just on the off chance, i can get the engine to run by bypassing the fuel pump and just using the primer, it doesn't seem to pump water very well? i've put a new impellar in and flushed out all the port holes etc but still seems just to just dribble out? i've only ran it for about 3mins and it did get hot, (not boilin) would that be enough time for the stat to open? i've seen one on youtube and it took him about five mins before it started to squart well,
many thanks dan

 

[SeaKaye12]

Re: mercury fuel pump problems

There again; it depends on what engine you have. A lot of the early ones did not even have a t-stat.

If that's the case, you should get a tell-tale stream almost immediately after starting.

In addition to the tell-tale...you should see water spitting out of the exhaust relief (mid-way up the leg) and out of the exhaust at the prop.

Chuck