im about to burn this this boat 1983merc 50hp wont start

[Faztbullet]

Re: im about to burn this this boat 1983merc 50hp wont start

Pulling plugs and laying them against block is a inaccurate test, the spark must be able to jump a least a 1/4-7/16 air gap. If it cannot jump this gap it will not fire under compression.

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

i dont lay it on the block i hold it suspended in the air by the rubber plug boot so i can see the spark jump from bottom of plug to block make bright blue spark ((( are the flat plugs the wrong ones? the serial # for the motor is 5683644 if this helps another question could the timing be off how do get the formal on the link and sync.

 

[Faztbullet]

Re: im about to burn this this boat 1983merc 50hp wont start

motor uses surface gaps,plug are correct design

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

thanks for the help everyone but some more questions how do i get the formal on the link and sync. this has to do with the timing right ?

 

[sschefer]

Re: im about to burn this this boat 1983merc 50hp wont start

Just a thought - You say the fuel pump is on the carb.. I'm pretty sure those are the accelerator pumps.

Looking at all of the testing you've done and assuming the results are correct, you have no fuel in the carbs or no pressure at the fuel pump. I suspect the fuel pump diaphram is shot. Take the fuel line off on the filter side leaving the filter on. Put a length of hose on the filter. Remove the plug wires, place the other end of the lenght of hose you attached into a container and crank the engine. Fuel should be under pressure at about 1 lb during cranking and it should pulse. If not, change the filter and make sure that the arrow is pointing in the correct flow direction. Try the test again. If no fuel, rebuild the fuel pump. To locate the fuel pump just follow the line back from the filter.

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

when i squeeze the primer bulb it gets hard ,flow arrow is in the right direction and also i already replaced that diaphragm you guys are talking about... when i squeeze the bulb it gets hard and when i force it past the hard point gas comes out of a little hole on the carb looks adjustable but it just screws on there.. am i sopos to have a fuel filter because this didnt have one when i bought it should i put one on and where like after the bulb?

 

[yrsouth]

Re: im about to burn this this boat 1983merc 50hp wont start

Not to sound stupid but, did you push the square button in on the throttle and then push it forward first?

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

yeah ive tried that ( throttle only button) nothing changes i think timing is off john was talking of syncing the formal on the link
how do i go about this ???

 

[Fuzzytbay]

Re: im about to burn this this boat 1983merc 50hp wont start

Here is the link to the link n sync page in the FAQ's
http://forums.iboats.com/showthread.php?t=168855

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

thanks for all the help but is there any thing else i can try before ripping into the timing or is this the next step to go ??

i know this is a foolish question but should i hear air on the fuel tank connection side like when i squeeze the primer bulb and i put my ear on the connection it sounds like air leaking is this normal or do i need a new fuel connector and hose??

 

[FZ1]

Re: im about to burn this this boat 1983merc 50hp wont start

I've had my fair share of carbs apart on my workbench. From what I have read I'm willing to bet that this motor sat a long while with gas in the carbs and you cleaned out some yellow/blue stinky crap outta them.

Even if not, are you POSITIVE you removed the floats from their hinge, pulled the needle valve out of the carb body, and cleaned/replaced the needle and its contact surface? Also, the low speed circuit most likely has an emulsion tube. (small tube with tiny holes in it pointing outwards) The last thing would be to find the factory setting for the idle speed screw, and how many turns out from lightly seated (because you removed this and pumped cleaner through the holes right?) All of these are an important part of a carb cleaning, If you dont' know what these things are, get a manual or get a professional to look at them.

It could be that you are just squeezing the bulb and building pressure behind a set of stuck needle valves, not getting fuel into the bowls!

Grant

 

[sicrx88]

Re: im about to burn this this boat 1983merc 50hp wont start

hey thanks grant

yes i am positive i did clean them very well lol i replaced everything except the aluminum carb bodies itself lol .... replace all needles jets floats seals and even got new gas to go along with it....she is also getting excelent spark so im stuck at this point as where to go next im thinking timing does anyone object or is this the next step to go

 

[hkeiner]

Re: im about to burn this this boat 1983merc 50hp wont start

Before doing a formal link and sync, you might try the following:

Remove the spark plugs, spray some 50:1 fuelil mix in to each cylinder, replace the spark plugs, and then try cranking the motor. If the motor does not even sputter a little trying to start after doing this, you can reasonably suspect an ignition problem (bad timing or weak spark). If the motor does sputter a little trying to start, then you can suspect the carbs some more. Just my thoughts.

 

[FZ1]

Re: im about to burn this this boat 1983merc 50hp wont start

No offence, but I'm thinking you missed something in the carb rebuild if its your first ever. You could be off 30 degrees on timing and still get some kind of ignition at idle speed.