# Any Ideas?



## popoeye (Jun 26, 2011)

So I picked up an 8 HP Mercury serial 0c112684. I can't find what year it is so if anyone knows a good website that would be great. Anyways I tried to get it started in a bucket and it would idle for about a minute and then stop. It would barely get up to a high enough idle to start pushing water out of the pee hole. I noticed that when it started to die, if I pushed the primer bubble it would keep going for about another 30 seconds. Now I am guessing it is either a fuel pump (if they have one, I am new to this) or I did rig the fuel line. They didn't have a mercury one, so I picked up a Johnson one and cut the end by the motor and put a mercury end on it. Could this be causing the lack of fuel. Any ideas would be great. Thanks.


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## 200racing (Jun 26, 2011)

https://www.maxrules.com/models/Merc_model_files/7p5-9p9.html
it says you have 1989 oil injected,rope start,long shaft.


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## popoeye (Jun 27, 2011)

Awesome, Thank you very much. What does the oil injected mean? I am guessing it means there is a spot to put the oil seperate. I didn't see it. Any idea where it might be. This might be why it wasn't running either cause I was running pre mixed. Also looking at that chart to attached I didn't see where it stated that it was oil injected. I was wondering if you could help me see this. Thanks a bunch again.


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## 200racing (Jun 27, 2011)

you never know PO might have taken it off or the site could be wrong.a manual would probably help you out.


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## popoeye (Jun 27, 2011)

Ok thanks again for all you help. I will let you know how it turns out.


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## FuzzyGrub (Jun 27, 2011)

200racing said:


> https://www.maxrules.com/models/Merc_model_files/7p5-9p9.html
> it says you have 1989 oil injected,rope start,long shaft.



Putting that serial number into MercuryPartsExpress.com did not have a schematic that looked like an oil injection system. Might have missed it, though.


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## popoeye (Jun 27, 2011)

I am not sure. I have never seen an oil injected so I am not sure what I am looking for. But I don't see anywhere on the engine that I could add oil. Does any one know if it is possible if the Johnson hookup on the gas tank could be effecting why it won't get going.


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## FuzzyGrub (Jun 27, 2011)

popoeye said:


> Does any one know if it is possible if the Johnson hookup on the gas tank could be effecting why it won't get going.



Highly unlikely that the J/E converted hose is causing the issue. If pumping the bulb keeps it running, the fuel pump or fuel passage problem.

Did you pull the fuel bowl or determine if gas was left in that motor while it was sitting all those years?


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## popoeye (Jun 27, 2011)

No I ordered the manual for it. I want to wait till I get it before I screw something up. I did check everything else and it looked good. I might just break down and take it to the shop. We will see.


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## FuzzyGrub (Jun 27, 2011)

An online link I have to some merc service manuals, started at "0DXXXXXX" and up for your 8hp.


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## popoeye (Jun 27, 2011)

Do you have that link. I didn't see it on your post.


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## FuzzyGrub (Jun 27, 2011)

popoeye said:


> Do you have that link. I didn't see it on your post.



You have a PM.


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## popoeye (Jun 27, 2011)

Ah thank you. Still new to this.


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## huntinfool (Jun 27, 2011)

Can you post a couple pics of it? If it is oil injected we should be able to help you find the oil tank and help you get it running.


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## FuzzyGrub (Jun 27, 2011)

huntinfool said:


> Can you post a couple pics of it? If it is oil injected we should be able to help you find the oil tank and help you get it running.



It would be best to be 100% sure. While I didn't see any oil pumps, or even mixing lines, in the schematics, a picture would provide the final say for the merc expierenced. 

If that 8hp had oil injection, it was discontinued by serial 0D281000. All models (6, 8, 9.9, 10, 15) covered by that merc service manual were premix.


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## popoeye (Jun 27, 2011)

I will post pics as soon as I can. I am having computer problems and am using a work computer right now. However I am pretty sure that it isn't an oil injected. I just got done take another good look and saw no oil reserve. However I am begging for the next piece of help. I want to start off by saying thank you so much for helping me with this learning process. I hope I can give back as much in the future. Well I got the engine running. However I had to push the throttle a little by hand. It ran great and everything looked good. How ever once I let go of the throttle on the carb it would die. So my uneducated guess is the carb needs to be adjusted. My question is where should I start to adjust the carb? I do have some experience with motorcycle 2 stroke carbs. I am just not sure about a outboard. Again everyone thanks for the help. I promise I will get this figured out soon. Look foward to hearing from you.


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## shawnfish (Jun 28, 2011)

popoeye, why did you have to use your hand to control the throttle???? sounds to me like you have a issue with the linkage between the throttle handle and your carb, if thats not it i would just buy a carb. kit and rebuild it. they are not expensive and it should be pretty easy for you if you have played with 2 cycle motorcycle carbs. jmho......


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## shawnfish (Jun 28, 2011)

popoeye, why did you have to use your hand to control the throttle???? sounds to me like you have a issue with the linkage between the throttle handle and your carb, if thats not it i would just buy a carb. kit and rebuild it. they are not expensive and it should be pretty easy for you if you have played with 2 cycle motorcycle carbs. jmho......


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## popoeye (Jun 28, 2011)

No the linkage is fine. I checked that. I didn't have to use my hand to control the throttle. I just used the throttle on the carb to give it a little more gas when it was neutral because it wouldn't idle or start. But just a little movement on the throttle it started right up and idled fine. Do you still think I need to rebuild that carb or does that sound like more of a adjustment. Thanks for the advice.


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## FuzzyGrub (Jun 28, 2011)

There will be an idle speed adjustment, and probably an idle mixture adjustment. You will have to see your manual to find the required rpm and procedure. It probably calls for in water and in gear. Do you have a tach? 

The manual will also have a procedure for the idle mixture. Usually it is repetitive, idle mixture, idle speed, idle mixture... for a few cycles.

If there is crap in the carb, the readings may be inconsistant, fluctuate, or mask issues.

Turning the idle speed up to keep it running is ok for testing. Just don't shift it into gear.

Given the long storage the motor had, its time to bite the bullit and order a carb kit and fuel pump diaphram kit, along with a new water impeller. 99% of the carb rebuild is a very thourouh cleaning. You could brief yourself on the procedures in the link I sent you, but wait for your specific SM before performing.

Other things you could do, while waiting for parts to arrive, and become good practice for seasonal maintenance:

- Drain and replace lower unit oil
- Do a compression Test
- Decarbonize (I use seafoam spray)
- New plugs gapped and installed (after decarb)


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## popoeye (Jun 28, 2011)

Thank you very much, that is what I was thinking but just wanted some moral support. I don't have a tach. Do they make ones that I can just buy and attach when I am tunning or is it something that I will have to have on for good. Thanks again for all the resources you are providing.


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## FuzzyGrub (Jun 28, 2011)

popoeye said:


> Thank you very much, that is what I was thinking but just wanted some moral support. I don't have a tach. Do they make ones that I can just buy and attach when I am tunning or is it something that I will have to have on for good. Thanks again for all the resources you are providing.



I purchased a Tiny Tach clone which you wrap a lead around a spark plug wire. The clone was more configurable than the Tiny Tach, which was purchased last winter to work on a new to me vintage snowmobile. I plan to use it on my small outboards and lawn equipment. I will be trying it on my Nissan 40C over the holiday weekend.

PS: Here is the one I got: https://trailtech.net/tto_tach-hour.html Paid around $30 off of ebay.


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## popoeye (Jun 28, 2011)

Thank you again. I will be ordering one today. Thanks you have been such a help. I am sure I will be back with more questions.


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## popoeye (Jun 30, 2011)

So I want to thank everyone for their help. I got the engine purring like a kitten, with all of the advice that you guys gave me. I have one last question for now. How hot should the water be coming out of the pee hole. I have noticed that the water coming out is pretty hot, and me never owning an outboard am not sure if this is normal. Thanks again for everything.


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## shawnfish (Jun 30, 2011)

popoeye said:


> So I want to thank everyone for their help. I got the engine purring like a kitten, with all of the advice that you guys gave me. I have one last question for now. How hot should the water be coming out of the pee hole. I have noticed that the water coming out is pretty hot, and me never owning an outboard am not sure if this is normal. Thanks again for everything.



you can buy temp. sticks for your motor model, they look like wax pencils and when your motor is warmed up( out on water running) you take the cover off and mark your head(or mark it before you start engine,i cant remember) and the wax will melt at a certain temp. to tell you if you are having a cooling issue, there are two sticks if i remember right. one to tell if you are hot and one to tell if you are cold. call your local shop and they will explain it to you better than me and should be able to get you the ones you need to test. p.s. the water will feel hot but if you cant hold your hand under it without pulling it away you probally have a problem...imo.........good luck!!!


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## FuzzyGrub (Jun 30, 2011)

popoeye said:


> So I want to thank everyone for their help. I got the engine purring like a kitten, with all of the advice that you guys gave me. I have one last question for now. How hot should the water be coming out of the pee hole. I have noticed that the water coming out is pretty hot, and me never owning an outboard am not sure if this is normal. Thanks again for everything.



It could be normal on a merc. My new to me merc, has the pee hole directly connected to the thermostat via hose. When you just start it up, it just dribbles, and was unnerving until looking at the design. Once the motor warmed up, a steady stream of water occured. It is much warmer than my other outboards because of that design. The others have a stream coming 100% of the time and is a mix of the water that went through head along with bypass water. 

Now, if you haven't changed that impeller yet... all the more reason to get at it asap.  The hot water could be just from low flow. Once the impeller has deteriated so far, pieces start to break off. Depending on design of pump housing, those pieces might start to flow into passages and start to plug things up. That can turn a relative easy repair into a big PITA.


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## FuzzyGrub (Jul 9, 2011)

popoeye said:


> Thank you again. I will be ordering one today. Thanks you have been such a help. I am sure I will be back with more questions.



I didn't get to try it on my Nissan 40C, but worked well on my Merc 25hp today. While I still prefer analog tach, this worked fine for setting idle speed and seeing what top wot rpm was. Slightly jumpy at idle, but was using the "fast" sampling setting.


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