Replacing fuel pump lines 85 Mercury 60hp

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Jun 28, 2006
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Having top end sluggish issues. Doesnt seem like my carbs are getting enough fuel. wont go above idle most of the time.. Give it gas and it bogs and dies. seafoam decarb, replaced gas, fuel filters but am looking to replace my fuel pump bladder/caps and fuel/pressure lines before i tackle the carbs. My question is can i just use 1/2 5/8" fuel line from the auto part store or do i need to order the part numbers i find in the mercury catalog . ?

This is for the fuel/pressure lines coming off the fuel pump. They dont seem to be anything special besides typical fuel line you'd find at the store.. any help is appreciated before i start this project..
 

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racerone

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Do a compression test first.----I do not believe your fuel lines are the issue here.-----As a test have an assistant operate the manual fuel pump.
 
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Manual Fuel pump? Do you mean the bulb on my fuel line coming from my gas tank? If so when its sluggish and i pump that bulb it increases in RPM and speed..
 
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Thats what i was thinking as i was squeezing the bulb out in the middle of the lake. HA fuel pump issue

wanted to replace the fuel/ pressure lines too.. Do i need to order the part numbers or can i just use fuel line from the auto parts store..
 
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The Force power

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Thats what i was thinking as i was squeezing the bulb out in the middle of the lake. HA fuel pump issue

wanted to replace the fuel/ pressure lines too.. Do i need to order the part numbers or can i just use fuel line from the auto parts store..

You can use any fuel-rated hoses, make sure the diameter is correct.
 
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After a compression test on all 3 cylinders both cold and after some run time the reading was 122 on all 3 cylinders.
 

MPrimeaux

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I'm by no means an outboard mechanic, but I would also suspect fuel pumps or simply needing to adjust carbs. I'm in the process of re-storing a '63 Merc 650. Actually put it in the water for the first time since I've owned it this weekend. It's doing almost the same thing. It'll crank and idle ok, but when I give it gas to get up on step it immediately bogs and dies unless I hit the choke right when I give it gas, then it'll get up on plane. I'm not sure it's winding out though. It think mine is too lean. I've re-built both fuel pumps, so I know it's not diaphragms. I'm pretty sure I just need to do some adjusting on the carbs. As for your original fuel line question, with the help of these guys on this forum I just bought regular old fuel line of the same size and some hose clamps. Cut the old hose off of the original fittings with a razor and put the new line on. It was going to cost like $100 to replace all of them with Mercury ones. Think I paid something like $10-15 for new fuel line.
 
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Nice. I have a 74 650. Its in the garage now but its a nice motor. needs some tlc.

I havent tried the choke trick.. i'll give it a go tomorrow while im out. I was going to try and back off the needles 1/8 of a turn on the carbs and see how it acts but i ordered the parts to rebuild the fuel pump today. That is why i posed that question because of the cost to replace all of the hoses via mercury dealer. So i'll opt for the auto parts store.. appreciate the answers.

When rebuilding the pump do i need to use any rtv or gasket sealant?
 

The Force power

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Nice. I have a 74 650. Its in the garage now but its a nice motor. needs some tlc.

I havent tried the choke trick.. i'll give it a go tomorrow while im out. I was going to try and back off the needles 1/8 of a turn on the carbs and see how it acts but i ordered the parts to rebuild the fuel pump today. That is why i posed that question because of the cost to replace all of the hoses via mercury dealer. So i'll opt for the auto parts store.. appreciate the answers.

When rebuilding the pump do i need to use any rtv or gasket sealant?

Ultimately you have to do; what you think is right but I would use automotive fuel-rated hoses & do not rtv use on gaskets
 
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WIll do on the hose.. i'll ask the guy and see what he has.. appreciate the time and answers on this one. had the boat out today.. wouldnt go full throttle but was up to 12 mph regularly. had it up to 27 at one point but its sporadic... after i rebuild fuel pump ill post my findings..
 
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Got my new fuel pump assembly in the mail today.. after looking at the included instructions i notice it says this.. (see pic)

Has anyone seen this before.. i saw another post similar to this on this forum but it didnt ever say the final solution.

Is this kit still ok as i do not believe, from my part number, that i have this raised cast in my fuel pump chamber..

Is it possible to still use these parts or do i order a different part number.. done all kinds of reading but havent found my exact answer.. figured i'd ask ya'll before i start taking things apart.
 

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