1989 3.0 Mercruiser / Alpha One Engine turns over but won't start , PLEASE HELP!!!

[Eric P]

Just recently purchased. The boat was taken out twice prior to purchasing and now it will not turn over. Boat cranks starter fires up belts are turning but it doesn't turn over. any ideas what could cause this? Plugs were changed, but still will not turn over. Any suggestions would be greatly appreciated, we are a small family and took a chance with the boat. Didn't expect this but i guess no one ever really does. :facepalm:

 

[81 Checkmate]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Boat cranks starter fires up belts are turning but it doesn't turn over.

Can you please clarify turn over?

Meaning it will not start!

 

[Eric P]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

When you turn the ignition, engine starts to "crank" but the engine never starts. it's getting gas to the carburetor cause you can see it dripping but can't figure out whats causing this.

 

[Don S]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Turning over normally means the starter is spinning the crankshaft. Starting is what happens when the engine keeps going after you release the key from the start position.

So, your engine turns over but won't start seems to be your problem. Do you have spark? Do you have fuel at the carb?

 

[CobiaXL]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Fuel,Spark,and Compression. 3 things needed to run...Remove air cleaner and check for fuel..Try pouring a little fuel in carb and hold throttle wide open, turn key over..Did it start?If not pull a spark plug and ground plug to a bolt on engine and have someone turn the key over..Did ya get spark??If so check cylinder compression.

 

[Eric P]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Thank you for the correction. Got Fuel at the carb and spark.

 

[CobiaXL]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Sounds like compression test is next..

 

[Eric P]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Thank you for the check list. I do notice that the past owner would give it one full pump and then have the throttle about 10, 11 'o'clock and he would get it to start,I was able to do the same once. but recently I drained the battery and had to charge it. I just cant imagine any boat having to be started with such difficulty though? Granted I am a newbie to this ?

 

[CobiaXL]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

All Engines with carburetor need some throttle to start cold.

 

[Don S]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Before you start doing compression tests and all. Since you have spark and have fuel, you may have to pump the throttle one to 5 times to get it started, and play with the throttle a bit to keep it running.
If you are expecting it to act like your cars EFI engine, it's not going to happen. Carbed engines take some work and getting used to to start and warm up correctly.
If you have it flooded (to much fuel) you may have to open the Throttle to wide open and crank it to get it cleared out and running.

 

[Eric P]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Thanks Don, It's a difficult balance when the battery starts to wear down and what is too much when it comes to throttle and starting. How many cranks would you say more or less are resonable ("turn of the key "just asking so i don't mess up the starter)? you think some ether in the carb is an option?

 

[CobiaXL]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

When properly setup,yours should start within 2-3 max cranks.Mine starts up at the bump of the key...When cold,I pump it once to give it shot of fuel and set the choke then let throttle bout 1/4 way open before I turn the key.Fires instantly and I usually allow it to high idle for 1-2 minutes then pull throttle back and she idles fine...Temps and air quality have a lot to do with it also.If you need ether,then u need a carb rebuild.

 

[81 Checkmate]

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Re: 1989 3.0 Mercruiser / Alpha One WON'T TURN OVER , PLEASE HELP!!!

Do not use starting fluid. After the boat has sat for for a bit and you have recharged battery.
If you have a start mode on your battery charger use it.

Try pumping the throtle 2 times, meaning push till wide open then back then push wide open then back to neutral then crank it maybe 4 - 5 times and see if it will fire.

Sometimes you have to put it all the way down to get it to start as Don said.

 

[45Auto]

Re: 1989 3.0 Mercruiser / Alpha One Engine turns over but won't start , PLEASE HELP!

How to crank your carbed boat - from the Mercruiser 120/140 Owners Manual. Pretty much duplicates what Cobiaxl said:

 

[merc120_81]

Re: 1989 3.0 Mercruiser / Alpha One Engine turns over but won't start , PLEASE HELP!

If I read the opening of the thread correctly, the writer mentioned, that plugs were changed. Check your fireing order is correct, 1 cylinder is usual on the front of an inline motor I4/I6, and the front left (Port side, front of the engine being where the water pump is) on a V6 or V8(double check if ford, but most chev/GM's are front left). Firing order is on a sticker on one of the valve covers usually. find #1 wire, I believe they go clockwise around the distributor. trace all the wires, make sure you didn't mix up a couple on the plug change.
Are you running fresh fuel, or is old and came with the boat?