problem with acceleration when cold

[aulet76]

Here is the situation, First of all I am new to owning a boat and know very little about outboard motors but I am a very skill handyman with a very intuitive and smart thinking. So with that in mind I am reaching out for some help to tackle this problem that I have with this boat I just bought.

The boat start fairly quickly and take a wile to bring the rev to a WOT. Ones there, I bring back down the throttle and go ahead and put it in gear. Ones I put the gear just die. I have hit the primer and then it will start. I go back a forth with this until finally get to start again...I let it warm up and after a while will take of but with a very low rpm...full throttle but hardly moving, I just let there for a while running very slow and out the blue get up and go like is no ones business and stay like that for most of the day unless I stop for more that 2 hours and I have to do it all over again. Look like when I put more weight in the boat I does take longer to get going and does not go as fast.

Last year when he service the boat they told us the boat was in great shape and the engine was great as good as it get and now this other guy tell me that is something mayor like that and told me the fix is around 500$ with out part...I believe he wanted to take me for a ride..Can some one please help me..

 

[aulet76]

Re: problem with acceleration when cold

by the way my motor is a 1976 johnson 70 hp model # 70EL76D

 

[Daviet]

Re: problem with acceleration when cold

First off, do not run your engine above about 1500 RPM in neutral. You need to do some basic checks, compression, spark and fuel delivery. Your carbs are non adjustable, the high and low speed orifices are fixed. Where the carbs drained for storage, is the fuel fresh, any air leaks in the fuel system?

 

[Monte1961]

Re: problem with acceleration when cold

Pull spark plugs and see what condition they are in, that will tell us alot of whats going on! Post back and let us know!

 

[aulet76]

Re: problem with acceleration when cold

Thanks, I will check on that today. On a side note my friend told me he did not drain the gas of the carb last year, and the boat was store outside last winter. We kind of lost contact since last time he used the boat and he just comfirm that. I will be replacing the spark plug today as well give it try in the water and see if that help improve the situation. Unless you recomend other way of checking it out. I am all ear and I am very thankful for all your help make me feel I am not alone doing this. Thank again.

 

[aulet76]

Re: problem with acceleration when cold

Ones I take the spark plug I will take some picture and a video of the engine running at iddle. I will document everything from now on so this could help feture people like me. By the way gas smell some time is there when I am running the engine is kind of like is not burning or something.

 

[Monte1961]

Re: problem with acceleration when cold

With the excessive fuel smell, sounds like you maybe running to rich. High speed circuit/s and or jet/s may have some garbage hung up in them. Might be looking at carb/s overhaul. Don't be surprised if plug/s look to be really black and wet. If so, that will confirm carb/s issue. A few things to mention. Do you have good compression? Is spark good and strong? Is fuel/oil mix fresh and mixed to ratio? Post back and let us know!

 

[emoney]

Re: problem with acceleration when cold

And, Aulet, keep in mind this isn't a car so don't compare the two when looking for "normal". I have a '79 140 and she's a little finicky when's she's cold, but since I know her routine, we never have any issues. Since you said that yours runs great after it's warmed up, then there may not be any issue. However, like Daviet & Monte are suggesting, in any "new-to-you" outboard you should start with Compression Test/Spark Test/Fuel system functioning test. If she wasn't drained and sat outside all winter uncovered, you can pretty much assume there hasn't been a ton of other maintenance done. If it were mine (and I know it's not), I'd do those tests and at the very least, clean/rebuild the carbs, change the impellar out, put new plugs in, and change the fuel lines from the tank to the carbs (and maybe the tank itself if it's old). Changing out fuel filters and any/all gaskets that look to be less than stellar. Spending a little time and energy now will save you TONS of headaches down the road. Lots of "break downs and bad feelings" happen on the water that could've been prevented with a little caring and planning. Good luck, and yes, any and all pics when there's a question will get you quicker and more precise answers.

 

[1946Zephyr]

Re: problem with acceleration when cold

First off, do not run your engine above about 1500 RPM in neutral. You need to do some basic checks, compression, spark and fuel delivery. Your carbs are non adjustable, the high and low speed orifices are fixed. Where the carbs drained for storage, is the fuel fresh, any air leaks in the fuel system?

Even the low speed is non-adjustable? Never seen this on an outboard before.

 

[Daviet]

Re: problem with acceleration when cold

Take a look at the breakdown below, it uses a idle orifice, not an adjustable screw.
http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ

 

[aulet76]

Re: problem with acceleration when cold

Hello Monte, here is the picture of the spark plug...

[/URL][/IMG] let me know if you can see the picture

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[Daviet]

Re: problem with acceleration when cold

Almost looks like the plug is rusty, have you run a compression test?

 

[aulet76]

Re: problem with acceleration when cold

for sure is black and a little wet, all of them.... How dificult is to take apart the carburator and overhaul it? what are the main components?

 

[aulet76]

Re: problem with acceleration when cold

could be...I am not sure because of the black build up... I am putting the new spark plug asap and give it a run in the water and I will take a video and post it.... Thanks again guys you all are awesome....

 

[aulet76]

Re: problem with acceleration when cold

by the way what is tool do I need to get to do a compresion test?

 

[Daviet]

Re: problem with acceleration when cold

I would start with the easy stuff first, what is the compression, will the spark jump a 7/16" air gap?
The carbs are not hard to overhaul, for me, do you have any experience in such maters? You might want to get a factory manual and do some reading and see if it is something you can do.

 

[Monte1961]

Re: problem with acceleration when cold

The tool is exactly that. It's called a compression gauge. By looking at the pictures you posted, it appears that they are a little bit rusty. I would be looking also for internal water leaks,IE> bad head gasket. I am not saying that's the problem, could be from the pictures or from just setting over the winter in damp area. Do as suggested first. We want it running as good as you do! Post back and let us know!

 

[Monte1961]

Re: problem with acceleration when cold

And as far as overhauling, do the same as you did in the pictures of the plugs. Take lots of pictures Pryor to removing carb/s and during tear-down. That way you will have the exact procedure of rebuilding and reinstalling. Use a good grade carb kit. Stay away from Sierras. My guess is, if you take your time, you will succeed and little to no issues. Then again, that's why were here! Note. If you choose to do the overhaul yourself, do not soak any plastic of any kind! All other metals from carb/s will be ok! Good luck and let us know!

 

[aulet76]

Re: problem with acceleration when cold

Just wondering, There is a black oil coming out of the botton by the propeller, What could that be? I am the process of changing the gas tank and changing the fuel pump and that is when it happened, It might have something to do with the fack that I took the fuel pump out but no sure.....I am trying to rebuild the stuff that it seen to be the oldest stuff first. Last, as previously mention I replace the spark plug and did the same problem with the acceleration when in the water, Any sugestions? by way the calibration it was set at 26 but not sure if that was right gap, I just use the one that was set on it from last time.

 

[aulet76]

Re: problem with acceleration when cold

I am glad to anounce that my motor is running superb in comparison to when I got it. I put a new gas tank and clean fuel mix with sea foam and that was all....Every day is getting better and better I think the carbs are cleaning as I use it. Thanks guys for all the adivce, I will be doing the carb overhauling next year but the guy for my local boat service shop is going to give a deal we will see.