76' Mercury 1150 Starting problem

[Billy B Boating]

I have a 76 Mercury 1500 tunderbolt that had been in storage for over 2 years due to military service. Prior to storage, I had fogged the engine, let the fuel run out of the motor, and drained the fuel tank. Recently I went to start the motor with freash fuel. The motor did start then it stopped. I have checked spark, fuel pump, timing, and basically everything. After putting in new spark plugs, the engine did fire. It then quickly began it's "not wanting to fire" routine. Any suggestions?

 

[tashasdaddy]

Re: 76' Mercury 1150 Starting problem

are you getting spark on all 6 cylinders. i had one of those, on a cold start you have to almost flood it to start it. i would pump my bulb till hard, then put my knee on it a couple of times, to force fuel. fast idle lever all the way up. good strong battery, good battery cables, has to turn +-300 roms to start.

 

[Inline6]

Re: 76' Mercury 1150 Starting problem

As tasahasdaddy suggest to start these engines they have to be primed with fuel much more so than you would think. Then they will start. Follow his advice and try this;

Set the carb idle mixture screws at 1-3/4 turn out from lightly seated. The carb choke plates often do not fit snug against the carb body. Take a look at them and try to adjust them tighter - make sure they do not hang-up though. You should hear the choke solenoid "click".

If that does not do the trick you may have to get a squirt bottle of pre-mix to help prime for starting.

Also, tilt the engine down as far as you can to help the fuel flow into the carbs during this process.

Part of the problem is you have to pump the primer bulb pretty hard to get fuel to leak past the carb needle / seats. On the other hand the harder you pump the bulb the more you will stretch the fuel pump rubber diaphram(s).

Good Luck!
Inline6

 

[daveswaves]

Re: 76' Mercury 1150 Starting problem

Fuel could certainly be the problem,however, a common problem on the inlines is wiring rot. The insulation is 30 plus years old and may have crumbled away, causing a short in the ignition. Have a good look at it. A less common problem is the switch box. Double check the connections there, the multi colored plastic backing behind the nuts tends to crack and the connection to the terminal is no longer tight.

 

[Billy B Boating]

Re: 76' Mercury 1150 Starting problem

Thank you. I will certainly try these things and let you all know how it went.

 

[cschultze]

Re: 72' Mercury 1500 Starting problem

Re: 72' Mercury 1500 Starting problem

I have a 72 mercury 150hp that is not getting any spark and i've noticed the wires are all roted. I am trying to replace all of them but i've been told it could also be the power pack or the trigger inside of the distributer. Any suggestions or trouble shooting ideas

 

[Chris1956]

Re: 76' Mercury 1150 Starting problem

You might start a new thread. There is a test for distributor-based ignition systems, on he cdielectronics.com web site. Of course, your wiring needs to be decent enought to run the test.