Link and Sync questions

[wasilvers]

So my motor seems like it could run better, especially at low speed. Sometimes she runs fine, then she seems like she misses a few times, then fine. At WOT, she runs great. I'm thinking a good tune up / link & sync of the carbs, adjust idle levers etc is in order.

Has anyone done this themself before?
Can a guy who fiddles with small engines handle this? I've rebuilt 4-5 mowers before and used rebuild kits on a number of 2 cycle carbs (chainsaws and trimmers) - but never had to really adjust anything except fuel mixture screws.
To adjust the degrees before top dead center, I'm assuming I'll need a timing light for this... any suggestions on what to buy?

I'm thinking it might be better to get her in a shop for all this, but I'd hate to spend tons of money since I just finished the boat up and cash is kind of short now.

Thanks for any help.

Will

 

[blimp]

You should be able to do it without a timing light, depending on the manufacturer. What kind of motor is it?

I highly recommend getting the *factory* service manual for whatever motor you have, they are invaluable for stuff like this and it will save you tons of money in the long run. If you have rebuilt mowers, you can do pretty much anything on an outboard.

Ebay is a great place to look for older manuals, they are frequently cheaper than you can find from the manufacturer or publishing websites.

best of luck.

 

[blimp]

https://cgi.ebay.com/ebaymotors/Evinrude-Johnson-40-45-50-55-HP-Service-Manual-1991-OMC-_W0QQcmdZViewItemQQhashZitem483ae61f32QQitemZ310225805106QQptZMotorsQ5fManualsQ5fLiterature


saw your link to your rebuild thread.

if yours is a 1991...

 

[Captain Ahab]

wasilvers - not uncommon for those 2 stroke outboards to pop and miss a little at idle or low throttle, they like to have some RPM to work effectively.

Before you start fixing things that might not be broke:


1. Make sure your fuel lines are all good and the bulb stays hard, often a slight air leak in the fuel line will cause the engine to stutter

2. Change the plugs and wires; and,

3. Make sure all your linkage and such is well lubricated

 

[wasilvers]

Captain - The bulb stays '3/4 hard' - which I guess would be hard enough. That means at the end of a day - like 4 gallons of gas later, I can squeeze it and it only compresses a small little bit. It also feels this way if it is parked, like last night I was fiddling with the motor and gave it a squeeze. It didn't squeeze much of anything. Should it be rock hard all the time?

It does stutter a bit unless RPM's are up over 1200. After a run back to the launch, it will die while trying to load the boat anytime I put it in gear unless I increase RPM's first (with the warm up lever) then toss it in gear. I think the lower RPM needs adjustment, but it is pretty far adjusted right now. Last night I just increased the rpm with the warm-up lever. Haven't had a chance to try it on the lake yet, but I'm hoping it doesn't stall while loading. It makes for some fun running around at the ramp to avoid hitting stuff when it stalls out.

Blimp - You are close! I's a 1989 - I downloaded a portion of the manual for it from the motor's section of this site. It has more info in it than the last set of manuals I paid $100 for from the last engine. It even tells how to to the sync and adjust everything. I'm just chicken I guess.

If I screw up a mower, I can buy another cheap enough - If I screw up an outboard, them things is pricy!

 

[blimp]

Nice! I would still check out a factory manual, those download links are to clymer manual, which are very generic and apply to many motors. Nothing beats factory service for specifics to your engine, especially for something so detailed as a link n sync.

 

[Pappy]

Didn't mention the make or horsepower of the engine. Can help if you fill me in a little better.
On the primer bulb - When running, the bulb should never stay hard and cannot. The primer bulb is only pressurized when you initially squeeze it to the point of closing the needle and seats in the carb or carbs. From the point that the engine starts, the entire fuel line including the primer bulb is on the suction side of the engine's fuel pump. The engine fuel pump is pulling fuel from the intake at the bottom of the tank through the primer bulb and the rest of the line and to the engine. As a result the bulb softens and this is normal.

 

[wasilvers]

Sorry, here's my engine info -

1989 50 hp Evinrude 2 cycle Model #E50BELCEC

 

[Pappy]

On the stbd side of your engine (side with the control cables) and looking at your carburetors, you will find a silver vertical rod that connects the upper carb to the lower carb. You will also find a roller and arm connected to the lower carb and should be very close to or touching a cam connected to your throttle advance arm. On the cam you will find a mark. The carbs should only start to open when the mark lines up with the center of the roller as the throttle is advanced. Easy way to figure out whether you need to re sync & link your engine is to start it and, using a screwdriver, loosen the arm with the roller. If the engine changes RPM then that setting is in need of improvement. Secondly, the vertical link to the top carb also has an adjustment that can be loosened with a screwdriver, it's location is on the top carb. Loosen while running and again, if your engine changes RPM, you need to reset both carbs to a closed position. The vertical link is always adjusted first and the pick-up point on the cam is adjusted second. It's easy. Idle RPM should always be adjusted in the water and you should shoot for around 750 in-gear (give or take). After all adjustments have been made you can then adjust or re-adjust your throttle cable to close the carbs when the control box returns to idle or shifted into neutral.

 

[wasilvers]

Looks like I have a Friday night project

 

[wasilvers]

Pappy - took a look last night. Based on what you said, it really is out of wack. I'll have to wait for better weather to start adjusting it though. Thanks for the help - I printed it off and have it next to the motor for later.

Will