I have an old merc that needs help

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cobrar543
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I have an old merc that needs help

Post by cobrar543 » Mon Jul 06, 2009 11:27 am

Does anyone know a good mechanic for these? its a 90 hp and seems to have 3 Carbs, no Fuel filter and after some bad fuel additive its only running on two or so carbs..I have cleaned the lines, used liquid tune up, Sprayed carb cleaner but no matter what I do it wont open up anymore on the water...It starts fine, runs smooth..but when I try to speed up its just goes about 10mph and starts to cough and choke out if you try to go any faster. I have ordered a used fuel pump to try to change that out next...any one got any help out there for a very poor mecnaniclly inclinded person?

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mallard83
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RE:I have an old merc that needs help

Post by mallard83 » Fri Jul 10, 2009 3:36 pm

Are you sure it is a carb problem? Could it possiby be an ignition problem (i.e. no spark). Have you checked the jets? What about the float? The float may be seized in one carb. Just ideas.

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Amx
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RE:I have an old merc that needs help

Post by Amx » Fri Jul 10, 2009 3:55 pm

Try changing the plugs with new plugs. In case they are fouled too bad to clean. At least test them.
Last edited by Anonymous on Fri Jul 10, 2009 3:59 pm, edited 1 time in total.
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tallman8251
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RE:I have an old merc that needs help

Post by tallman8251 » Sat Jul 18, 2009 8:42 pm

Not sure if you want to go this far, but there is a guy called Danny Harper up in Bham who works out of his house. Went to all the schools etc. Great rates and honest man.

Danny Harper
(360) 383-9095
Bellingham, WA 98226


I had him do a bunch of work on my old mercruiser and he did a great job.

cobrar543
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RE:I have an old merc that needs help

Post by cobrar543 » Sun Jul 19, 2009 9:06 am

Thanks..will call him tomorrow...I have tryed everything I can do to solve the problem. time to turn it over to a pro!

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RE:I have an old merc that needs help

Post by AdsBot [Google] » Sun Jul 19, 2009 12:57 pm

cobrar543 wrote:Does anyone know a good mechanic for these? its a 90 hp and seems to have 3 Carbs, no Fuel filter and after some bad fuel additive its only running on two or so carbs..I have cleaned the lines, used liquid tune up, Sprayed carb cleaner but no matter what I do it wont open up anymore on the water...It starts fine, runs smooth..but when I try to speed up its just goes about 10mph and starts to cough and choke out if you try to go any faster. I have ordered a used fuel pump to try to change that out next...any one got any help out there for a very poor mecnaniclly inclinded person?
Call Greg at Tacoma Marine Repair. (1106 St Paul Ave, Tacoma, WA.
(253) 272-9014. ) He is the best in the Northwest. You won’t be disappointed!
Last edited by Anonymous on Sun Jul 19, 2009 12:58 pm, edited 1 time in total.

urbanspatialpatterns
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RE:I have an old merc that needs help

Post by urbanspatialpatterns » Sun Jul 19, 2009 2:01 pm

WAIT!

I am in the middle of this very same repair on a mid 60's 950ss with the tri-ple carb stack.

Your problem is a bad diaphragm fuel filter in one carb, i think the bottom (or is it top?) one is usually the culprit.
I am only shadetree mechanic so I amy have some terminology slightly off.

My motor was exactly as you describe, and you sound mechanically inclined enough to have checked the norms.

When I took the carbs off and apart two were perfectly fine but one was compromised and had corrosion.
Inside are these 2 or maybe 4 dime sized filter things. looks like a fancy something you might screw inside of your sink faucet as a screen or filter.
Maybe 2-3 dimes thick, plastic and metal.

Mine were frozen closed from corrosion.

Ordered more online.

Some looked fine but when i tested them (treid to blow through them) they were stuck as well.
The ones in the other 2 carbs worked fine and when tested you could feel the diaphragms move and vibrate.

I would bet money on it.

It is actually a very straight-forward fix.
You can come by and help me put mine back together ifn you wanna see em.

2muchtq
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RE:I have an old merc that needs help

Post by 2muchtq » Sun Jul 19, 2009 3:19 pm

This topic caught my eye...


Anyone dealt with Sky Valley Marine in Monroe, WA?


I have had a couple people tell me he knows his stuff and is reasonably priced.



As for the motor... its nothing major, just seems to load up quite fast and needs to figure out what is wrong with my tachometer. (the wire to the tach from the motor meters out to be good.... so I have no clue what the problem is)

Figured a used boat could use a good tune up.

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