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Merc 57 mech fuel pump rebuild

jconti

New member
"hi,

new to the post. have


"hi,

new to the post. have read it some and you all seem very knowledgeable, and helpful. i have a decrepid old 5.7 merc in my 79' century 4000 cuddy. i heated a head about 4 yrs ago. had the heads resurfaced, and a 3 angle valve job done. replaced all manif. rsrs. elbows. ect. boat ran a good season. since then i been fighting all the peripherals rotting away. still has good pressure on all 8, so i think its worth ressurecting. when started it will run at idle. won't power up on water dies out and creeps back to dock. a dealer lookt it over. they say i need to rebuild carb, replace mech. fuel pump, and maybe distributor.

i'm dunking the carb now in a ultrasonic tank at 180 deg. F. in a aquaworks mm-dip cleaning solution. (supposed to be thorough but real safe on all metals) . the carb is a m mercarb 2B rochester. i took the fuel pump apart. not sure of model, but i think its one of the more common ones. anyway the diaphragm looks ok as do the syphon valves. i cant get the diaphrams (and thier linkage) out of the housing -there is 2 rubber diaphrams w a ring piece in between them - all on a rod w/ a spring behind it. how does it come out? and since it looks ok. i'm gona just clean it up n put it back together i guess. and im gonna clean up the old mallory distributor and put a conversion kit in it to go electronic. gonna clean up cables on bat n starter, and replace any questionable electrical wires. oh, the dealer also said the fly weights in the distributor might be stuck. are they under the points in the bottom of the distributor?

so, am i on the right track and should i redo anything else. i want a solid unit when i'm done, but like everybody rite now , i wanna spend as little as possible to make it happen.any advice is appreciated."
 
yes the fly wiegts are under t

yes the fly wiegts are under the plate that your points fasten too. should be 2maybe three screws that hold that plate on
 
"you won't find a rebuild

"you won't find a rebuild kit for the fuel pump; stay on the path you with it and check the fuel pressure when you get it back together. If low or leaking, time to replace it with a marine one. A good parts store should be able to order you one from Airtex.

I'd suggest getting a full electronic distributor (marine grade); both the pickup and the advance. Around the salt water, those mallory springs had a short life and we got tired of replacing them. You can find running takeouts on ebay or check the marine salvage shops. If you go with thte pickup kit, invest a few buck in a 'timing tape' and check the advance mechanism using the tape. Laack of spaark advance will keep the engine from making power at higher rpms. good luck"
 
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