No Start Again!?! '83 Merc 470

[WaterKrafter]

I am on the edge...two weeks ago came across new-to-me cater fuel pump and Merc 2bl carb to replace old pump and Rochester 2bl carb. I installed and tested at ramp...adjusted linkage, she fired and idled at 650 rpm's without a hickup. Ok. Didnt want to leave ramp without a first mate to help row back should anything go south. Ok. Put her away until day and a half later to go out for test run. No Start!?! I piddled around scrathing my head...humm...ok. Well, I better check for bad fuel. Bad fuel and siphoned out the tank and put in fresh gas, new water sep. filter, pump fiter, inline inlet fiter...no start. Checked pump...pumping. In the meantime I put on new cap & rotor, new plugs, checked and adjusted timing to specs, checked for spark, pulled, disassembled, cleaned and reassembled carb and remounted.
Tried to fire her up after and found flooding again and again...

Any body have any directions for me? I have been on this thing for months. Plug wires are on firing order as spec 1342. I don't know where to go next!?! BooHoo Me!!!

 

[alldodge]

found flooding again and again...

If its flooding then its the carb. It might be an incorrect float setting, spec of dirt in the needle seat, bad needle seat

 

[Scott Danforth]

what was the problem with the original pump and carb?

even if you get a new to you carb that is used, you still have to pull it apart, clean it, and install all new gaskets.

 

[WaterKrafter]

Thanks AllDodge and Mr. DanForth! It just so happens that after removing some glazzed plugs and replacing with new, I added 3/16 of gasket material to my fuel pump flange to lower what I guessed to be too much preasure (thus the flooding) and readdjusted my float level & drop to the "T". Then I cleaned out accelerator pump and well with parts cleaner again along with choke adjustment . Charged both batteries again and fired her up! She came alive upon 2cnd key/crank and after two pumps of throttle and settled at 700 rpms in about 3 minutes! Perfect idle! I zhut her down ready to sea try mananna! YES!
Wow that feels great after all my efforts and time here in the forums, etc. Fresh oil change, coolant and impellar I allready did earlier on! I hope she starts as well in the morning...afterall it is a BOAT!?! Right?
Hats off to everyone here and the dedicated and sincere help to us who so gravely need it!
Ahoy!

 

[Scott Danforth]

Thanks AllDodge and Mr. DanForth! It just so happens that after removing some glazzed plugs and replacing with new, I added 3/16 of gasket material to my fuel pump flange to lower what I guessed to be too much preasure (thus the flooding) and readdjusted my float level & drop to the "T". Then I cleaned out accelerator pump and well with parts cleaner again along with choke adjustment . Charged both batteries again and fired her up! She came alive upon 2cnd key/crank and after two pumps of throttle and settled at 700 rpms in about 3 minutes! Perfect idle! I zhut her down ready to sea try mananna! YES!
Wow that feels great after all my efforts and time here in the forums, etc. Fresh oil change, coolant and impellar I allready did earlier on! I hope she starts as well in the morning...afterall it is a BOAT!?! Right?
Hats off to everyone here and the dedicated and sincere help to us who so gravely need it!
Ahoy!

adding gasket thickness to the fuel pump is not smart. it limits the pump flow, not the pressure. pressure is the absence of flow and the mechanical pump cant develop more than 7psi which any carb should be able to handle without a problem.... unless there is an issue with the carb

fix the needle and seat or the float if the carb is not holding the fuel pump at bay

 

[stonyloam]

Adding to the thickness of the pump gasket was the key. It is very common for new fuel pumps to develop too much pressure when installed in a 470. The arm geometry is the problem and is solved by adding a spacer as you did. You might borrow a fuel pressure gauge from Autozone to check it. I think it should be about 3-4 psi.