Mercruiser Starting Issues

[ShaneCarroll]

I have a 1992 Mercruiser 3.0L. It is very difficult to start, and the engine acts like it is going to cut off when in neutral, it sputters and starts cutting out, but runs great otherwise. I just bought this boat, and it has a new carburetor. In order to start it, I remove a little rubber grommet that does not allow any air out of the carburetor, and once it starts I replace the cap. Any advice?

 

[Don S]

Re: Mercruiser Starting Issues

Welcome to iboats shane (or Carroll) but, you are going to have to describe your problem a lot better than that if you want an answer.
I for one don't understand

acts like it wants to cut off when in neutral, but runs great otherwise.

 

[Bondo]

Re: Mercruiser Starting Issues

I remove a little rubber grommet that does not allow any air out of the carburetor, and once it starts I replace the cap.

Ayuh,.. What Grommet,..??

It probably just needs a Full Tune-Up,+ service..

 

[Tail_Gunner]

Re: Mercruiser Starting Issues

Finally one i can respond to with a common experience......you dont have efi you might have to pump the throttle 3-5 time to prime the carb..:redface:...... trust me it works wonders..

 

[JustJason]

Re: Mercruiser Starting Issues

5 Times?????? Who are you.... Noah waiting for the great flood??

 

[chiefalen]

Re: Mercruiser Starting Issues

Would you please post a pic of the grommet.

Also go to the " Adults only " at the top of the forums and go down to how to start a carbed motor.

Good luck !

 

[mthieme]

Re: Mercruiser Starting Issues

New to you boat....new carb....a red flag should be going up.
Don't know what the rubber piece is you are referring to, but it seems like you have to screw with the fuel and/or air to get it running. I'm thinking the rubber piece could be a vacuum cap/plug (?).
I would start by adjusting the carb and see what happens.
Is it idling at the proper rpm? or is it too low?
Looking down the carb with it idling, do you see gas dripping?
Is the choke working?

 

[Don S]

Re: Mercruiser Starting Issues

New you you boat....new carb....a red flag should be going up.

To 'ell with the red flag, WHITE FLAG flying. What is a New you you boat....new carb....

That one hurt to read

 

[mthieme]

Re: Mercruiser Starting Issues

LOL.
oops. Sorry for the typo. I edited it...any better?
I'm sure it's still far from the Queen's English.

 

[Don S]

Re: Mercruiser Starting Issues

Ahhhhhhhh, much better

 

[ShaneCarroll]

Re: Mercruiser Starting Issues

Thank you for all the responses and the help. Pumping the throttle 3 times works great, from a cold start. Once the engine is warm, it is nearly impossible to start. Example: I took the boat out today, cold start was great, let it run for 1 and 1/2 hours, cut it off on the island, went to restart it, and same dilemma. The boat runs great, no bogging down, quick plane, and everything, I just cannot get it started. Please help. Thank you.

 

[Don S]

Re: Mercruiser Starting Issues

You aren't pumping the throttle when the engine is warm are you?

 

[ShaneCarroll]

Re: Mercruiser Starting Issues

No, I do not pump the throttle when it is warm. Being stranded on the island, I pretty much killed the battery trying to start it, and on top of that, the belt that goes over the alternator and power steering pump (I guess, power steering went out) broke. I plan on replacing both belts as a precaution. The one pretty much shredded, not able to get any info from it, do you happen to know the sizes of the two belts? I appreciate all of the help and man, you are a genius. If you are ever in Tampa and need anything, definitely let me know.

 

[mthieme]

Re: Mercruiser Starting Issues

It's late, I'm getting tired and I'm starting to imagine all kindsa things wrong here. I may be wrong, but I think you might have (at least) another issue. I'm assuming it did nothing - no spark or rather it didn't even try to fire - just spun.
Try this. Make up a jumper wire that will stretch from your battery to the coil and keep it on board. Next time you have a hard time starting it, could be in the driveway or at the pier, don't risk getting stranded, connect the wire on the + side of the battery and the the other end at the coil. You should be getting 12V to the coil. If it starts, replace the starter solenoid.

 

[Fishermark]

Re: Mercruiser Starting Issues

The one pretty much shredded, not able to get any info from it, do you happen to know the sizes of the two belts?

Regarding the belts, be sure to check the condition of your pulleys. Since you boat in salt water, things tend to get rusty. (Is that an understatement or what?? ). Your pulleys need to be free of rust and smooth. Sand them good if they are rusty.


Regarding the carb. Have you checked to make sure your choke is working properly?

If you are ever in Tampa and need anything, definitely let me know.

I do a lot of fishing there in Tampa Bay. Welcome to the board!

 

[Bondo]

Re: Mercruiser Starting Issues

and I'm starting to imagine all kindsa things wrong here.

Ayuh,.. Same here....

How long has it been since this boat was Serviced by somebody who knew what they were Doing,..??

 

[ShaneCarroll]

Re: Mercruiser Starting Issues

I appreciate all the help. Regarding when the boat was last serviced, I just purchased it last Saturday, and the seller gave me a receipt to where the carburetor had just been replaced within the last 4 months. The pulleys are not rusted, the engine is actually quite clean for the age. I always, ALWAYS flush the engine when I get the boat out of the bay, and clean the engine, as well as spray WD-40 on all the metal, not the pulleys though (make the belts slip). About the belts, anyone know the sizes, they are not in the manual? Thanks again.

 

[Bondo]

Re: Mercruiser Starting Issues

About the belts, anyone know the sizes, they are not in the manual?

Ayuh,...

Take the serial # from your motor,+ go to a Mercruiser Parts Look-up,...
You'll be able to figure it out from there...

Here at iboats they should be,...
18-15400 for the Alt.
18-15370 for the P/S..

 

[ShaneCarroll]

Re: Mercruiser Starting Issues

I appreciate all of the help. I replaced both belts. I adjusted the air intake on the carburetor, replaced the spark plugs (although they didn't look that bad) and checked all connections for that purple wire that everyone mentions which goes through all gauges. So far so good, I started it in the yard, let it run for a while, cut it off, and it fired right back up. That is a huge step forward from what it was doing. I'm taking it on a sea trial right now, hopefully all goes well. Thanks again.

 

[Fishermark]

Re: Mercruiser Starting Issues

I'm taking it on a sea trial right now, hopefully all goes well. Thanks again.

It's a good idea to be sure your SeaTow is paid up first! Good luck!