Need help 1973 omc

[chicken nugget]

Hi I have a 73 omc stern drive 165 hp, It's the has the gm inline 6...I did a tune up on it and rebuilt the carb took it out on the lake and it ran great. The first day, Took it out again and it starts up great at the dock and idle out past the no wake zone as soon as I hit the throttle it dies, But starts up fine when I do get it to go and get up on plane for about a minute it dies it acts like it running out of fuel. Went home and took off the gas line from the tank and blew it out, and took out the line from the tank and cleaned the filter out on the end. put it all back together hooked it up to the hose and started up just fine.. oh yeah it will start and run fine on the hoase but in the lake when you try to throtle up it dies. Could it be my fuel pump?

 

[bertos]

Re: Need help 1973 omc

i had the same problem i had to replace the filter in the carb, also i had a water in in the fuel, replaced my water seperator. and also changed the inline fuel filter. good luck happy boating

 

[cr2k]

Re: Need help 1973 omc

Other than what Bertos sez about all I can think of is the accelerator pump in the carb. Common on the GM carbs and Mercarbs. Have someone pump the throttle (not running) while looking in the carb. Should see gas squirting from upper area in to the opening. If no squirt or dribble, carb needs OH. Either the passage is plugged with corrosion or the pump is bad. If you or who ever does a carb OH check the spring form the old pump as the newer ones have been weaker and can cause acceleration problems, use the stiffer spring.

on land and hose. no load on engine it may hesitate but should rev. In water with load, it may die or backfire.

 

[P 0 P E Y E]

Re: Need help 1973 omc

accelerator pump is for sudden acceleration and starting aid.

Try a slow acceleration next time.

But for now, test your vacuum advance by sucking on the hose, hold your tongue on the hose and see it it holds suction and the distributor timing changes.

Check your gas and fuel tank vent..check a bunch of stuff to eliminate or narrow down the possibilities

 

[chicken nugget]

Re: Need help 1973 omc

Other than what Bertos sez about all I can think of is the accelerator pump in the carb. Common on the GM carbs and Mercarbs. Have someone pump the throttle (not running) while looking in the carb. Should see gas squirting from upper area in to the opening. If no squirt or dribble, carb needs OH. Either the passage is plugged with corrosion or the pump is bad. If you or who ever does a carb OH check the spring form the old pump as the newer ones have been weaker and can cause acceleration problems, use the stiffer spring.

on land and hose. no load on engine it may hesitate but should rev. In water with load, it may die or backfire.

Yes thats what it does on hose no problem. But on the other hand in the lake she will idle great no problems at all, soon as you try to go faster it dies. I got it to go at half throttle and it will die but it will start right back up. I'm going to check accelerator pump.

 

[chicken nugget]

Re: Need help 1973 omc

accelerator pump is for sudden acceleration and starting aid.

Try a slow acceleration next time.

But for now, test your vacuum advance by sucking on the hose, hold your tongue on the hose and see it it holds suction and the distributor timing changes.

Check your gas and fuel tank vent..check a bunch of stuff to eliminate or narrow down the possibilities

I did try slow acceleration it worked for a sec but would die any way. Where is vacume advance?

 

[chicken nugget]

Re: Need help 1973 omc

i had the same problem i had to replace the filter in the carb, also i had a water in in the fuel, replaced my water seperator. and also changed the inline fuel filter. good luck happy boating

:Thanks for your input, I took out the fuel line inside the tank and cleaned out the screen on the end changed the filter in the fuel pump and the filter in the carb also put in a inline filter between the fuel pump and carb and the boat runs AWSOME THANKS AGAIN!!!!!!