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Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 15031
Experience:  Degree in Marine Technology. Gas and diesel marine mechanic.
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I have a 115 Yamaha 4 stroke outboard emgine. It has 2 x 12

Customer Question

I have a 115 Yamaha 4 stroke outboard emgine. It has 2 x 12 volt batteries. Both are flat. Can we jumpstart 1 with car jumper leads off the 12 volt car battery ?
Submitted: 1 year ago.
Category: Boat
Expert:  Jason replied 1 year ago.

Good morning, my name is ***** ***** am I speaking with?

Outboard charging systems are fairly sensitive in nature to voltage spikes. Some people do jump start batteries and get away with it. Others jump start engines and the voltage regulator portion of the charging system burns up. Personally I would disconnect the batteries and hook them up to a charger and charge them over night. That is the only way to guarantee not damaging the charging system on the engine.

Expert:  Jason replied 1 year ago.

I think that should do it. But I do want to make sure you are happy with my service before you go. If you had a further question on the issue by all means feel free to ask. If not, Just in case you do not understand the way the website works (and some folks do not). You do have to put forth a positive rating in order for it to credit me for helping you. When ratings are not done, the website simply keeps your deposit and they will not credit me. The ratings box is located at the top of the screen. To rate, you must select the star you wish and also confirm it. Please let me know if you run into any problems or errors when trying to do it. If you do have a problem, or if you can not see the ratings box which is at the top of the screen. Please reply back "I rate Jason's service _______" and fill in the blank.

Questions do not close out, so if you have to come back later on with follow up questions to the issue you still can even after doing a rating.

Thank you
Jason

Customer: replied 1 year ago.
Do both batteries charge together when the engine is running or do they charge individually ?
Expert:  Jason replied 1 year ago.

That depends on how your specific boat is wired up. Are you using an kind of battery switch, battery isolator, or battery charging relay? Or do you just have 2 batteries hooked up in parallel with no switching?

Customer: replied 1 year ago.
Hooked up in parallel with no switching.
Expert:  Jason replied 1 year ago.

If they are wired that way they would both charge at the same time when the engine is running.

Customer: replied 1 year ago.
Thanks but you haven't really answered my question properly concerning the make and model Yamaha 115 4 stroke.
I'll leave it. $38 badly spent.Regards
Mike
Expert:  Jason replied 1 year ago.

The only question I see was you asking if you can jumpstart the engine. And the answer to that is if you attempt it you risk damaging the charging system on the engine, so No, No you should not jumpstart it.

Did you have some other question about the engine that I missed? The website does charge you either way, but they don't credit me unless you put through a good rating for me. So I do want to make sure I get all your questions answered on the issue, was there something else?

Customer: replied 1 year ago.
Based on a battery and charging system of a Yamaha 115 4 stroke.
I'll leave it. Would have been cheaper to ring my local marine mechanic. Cheers ***** ***** in New Zealand
Expert:  Jason replied 1 year ago.

"Based on a battery and charging system of a Yamaha 115 4 stroke"

I'm sorry I don't understand you.

Customer: replied 1 year ago.
Don't worry about it. Forget it. Bye
Expert:  Jason replied 1 year ago.

okay

Expert:  Jason replied 1 year ago.

Please do not forget to put through a positive rating for me. Thank you and happy boating!

Jason

Expert:  Jason replied 1 year ago.

Hello, I noticed no rating has been put through. The website has charged you but they will not credit me for helping you out until that rating is complete. Did you have any further questions on the issue?

Thanks,
Jason

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