Ignition Timing

springbok

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I checked the timing on my 1988 25hp Evinrude by pointing a timing light at the protruded arrrow on the housing of the pull cord. It says on the engine block 30 degrees BTC. I'm getting a reading of about 12 degrees at idle? Doesn't sound right to me, I want to adjust the timing but have no idea where to start.... Any help would be appreciated.
 

OBJ

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Re: Ignition Timing

Springbok....You have to test timing at WOT on the water or there is another process to do this out of the water. Wait'll I find it. BRB.
 

OBJ

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Re: Ignition Timing

Springbok....You have to test timing at WOT on the water or there is another process to do this out of the water. Wait'll I find it. BRB.<br /><br />OK...Joe Reeeves posted this and should work for you.<br /><br />The full spark advance can be adjusted without have the engine running at near full throttle as follows. <br /><br />To set the timing on that engine, have the s/plugs out, and have the throttle at full, set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw (wire it against that stop if necessary). <br /><br />Rig a spark tester and have the spark gap set to 7/16". Hook up the timing light to the #1 plug wire. Crank the engine over and set the spark advance to 4° less than what the engine calls for. <br /><br />I don't know the full spark advance setting your engine calls for, but to pick a figure, say your engine calls for 28°, set the timing at 24°. The reasoning for the 4° difference is that when the engine is actually running, due to the nature of the solid state ignition componets, the engine gains the extra 4°. <br /><br />If you set the engine to its true setting at cranking speed, when running it will advance beyond its limit by 4° which will set up pre-ignition causing guaranteed piston damage! You don't want that to take place. <br /><br />No need to be concerned about the idle timing as that will take care of itself. The main concern is the full advance setting. <br /><br />Be sure to use your own engines spark advance settings, not the one I picked out of the air here in my notes.<br /><br />Hope this helps.
 

springbok

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Re: Ignition Timing

OBJ....Thanks a lot, I'll try that out and let you know how it goes.
 

springbok

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Re: Ignition Timing

OBJ, I started the proceedure that you reccomended but I think I ran into a problem? So far I did this step:<br />1. To set the timing on that engine, have the s/plugs out, and have the throttle at full, set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw (wire it against that stop if necessary). <br />In the next step after you set up the spark plug tester, you have to crank the engine and check the timing mark. My engine won't turn over in gear. In order to set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw the engine has to be in gear... Now what?
 

nina

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Feb 21, 2004
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Re: Ignition Timing

Don't worry about putting at full throttle. Of course you can't crank motor. Leave in neutral and unhook the linking arm that is under flywheel and then you can wire to stopper without putting the throttle control in gear. This will enable you to crank motor over.
 

Hooty

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Re: Ignition Timing

Manually move the timing ring until its against the timing stop screw and fasten it there with baling wire or something else suitable. Now, proceed with OBJ's instructions.<br /><br />c/6<br />Hooty
 

nina

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Re: Ignition Timing

If for some reason you have to have throttle wide open then open it with your fingers and put tool to hold open.
 

OBJ

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Re: Ignition Timing

Thanks guys for helping springbok....I kinda fergot about the neutral safety switch.
 

springbok

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Re: Ignition Timing

I checked the timing using the procedure and it was at apx 22 degrees instead of 26, so I set it to 26 degrees. Would 4 degrees make a big difference in performance? <br />Another question. In neutral when you advance the throttle past the point where the timer base can't move anymore because of the neutral saftey switch, is it normal for the engine to bogg and stall?
 

Hooty

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Re: Ignition Timing

If it were me, I'd set it back to 22*. That's the 4* OBJ was speaking of and it could be the difference between a piston with a hole in it and one without the hole.<br /><br />c/6<br />Hooty
 

springbok

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Re: Ignition Timing

It calls for 30 degrees thats why i set it to 26...
 

nordy

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Re: Ignition Timing

Hello Springbok, Hooty,<br /><br />could you explain me how to set the timing on my 30hp-Johnson, I think it's the same matter discussed here.<br />I suppose one can do it by screwing in or out the timing advance stop screw (with the rubber stop).<br /><br />Nordy from Germany
 

Hooty

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Re: Ignition Timing

but don't change anything until you're sure the timing is off. It doesn't change by itself.<br /><br />c/6<br />Hooty
 

CharlesW

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Re: Ignition Timing

One thing that I have noticed in this thread is the reference to 30 degrees advance.<br />That is probably correct for that engine, but it sure is a lot more than I remember my 1986 40hp Evinrude calling for. My manuals are 90 miles away right now. but I sure think I recall 19 degrees as the total advance for it.<br />It just strikes me as strange that the two motors would have that much of a timing differential. Since no one else has commented on it, it must not seem strange to anyone but me.<br /><br />Charles
 

springbok

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Re: Ignition Timing

Charles, there is a sticker on my engine that says "30* BTC" I'm assuming that this would be correct... I would consult your owners manual before setting it though...
 

CharlesW

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Re: Ignition Timing

Originally posted by springbok:<br />Charles, there is a sticker on my engine that says "30* BTC" I'm assuming that this would be correct... I would consult your owners manual before setting it though...
My concern was the 30 degree setting you are using. If it is correct, then great. If it is off by those 11 degrees, then not so great. If I get a chance I will ask my mechanic to check the OMC shop manual for the correct timing for your 1988 25 horse. Like I said, my Seloc and Clymer manuals are 90 miles away.<br /><br />Charles
 

CharlesW

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Re: Ignition Timing

Originally posted by CharlesW:<br />My concern was the 30 degree setting you are using. If it is correct, then great. If it is off by those 11 degrees, then not so great. If I get a chance I will ask my mechanic to check the OMC shop manual for the correct timing for your 1988 25 horse. Like I said, my Seloc and Clymer manuals are 90 miles away.
My mechanic was sick and not at work today and I was unable to find any of his OMC manuals.<br />But..., two Evinrude motors on stands in the shop both had yellow stickers on them. One said timing was 34*, don't remember the HP, the other was a 25 HP and the sticker on it most definitely said 30*.<br />Sorry to confuse the issue. Just didn't want you to take the tops out of the pistons.<br /><br />Charles
 
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