1998 Johnson 90 2 stroke timing procedure?

Lundman83

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Hi folks. I have a 1998 johnson J90 TLEDA that has never run right since i have owned it. (Used) this year, it will not start! I have fuel, as my plugs are wet when i pull them. (Fresh premium gas). It has nice bright blue spark on all plugs.
Can anyone tell me the proper procedure for setting the timing on this motor?

I can tell by the witness paint it has been changed from factory settings.

Also the timing pointer is ADJUSTABLE??? WTF? How am i to know the pointer is in the right location?
 

schematic

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Re: 1998 Johnson 90 2 stroke timing procedure?

Yes....you need a manual. Way too much typing for a one fingered pecker like me. Timing on 2-strokes is critical. Do it right, get a manual
 

Lundman83

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Re: 1998 Johnson 90 2 stroke timing procedure?

Ok sooooo
I pulled the carb drain plugs out and i got about a cup of straight injection oil!! No wonder it wouldnt fire! Flushed carbs out and put the timing back to the factory marks. It fired right up, and ran better than ive ever seen!

This boat was not used last summer. When i parked it, i ran the engine till the carbs were dry, so there was no oil in them at that time!
My oil tank is mounted on the floor of the boat. How did a diaphragm pump siphon that much oil into the carbs against gravity??

I didnt crank it enough to pump that oil there!

Wondering if this is the reason its always been a bi**h to start!

That and the timing.
Are these oil pumps problematic?

Schematic: any chance you could post a thread with the timing info? I dont want to wait weeks to get a manual!i am going to buy one but i wanna go fishin now!
 

Lundman83

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Re: 1998 Johnson 90 2 stroke timing procedure?

I dont think there is a vent in the oil cap, so mabey its forcing oil up the tube when ambient temps are high? I stored it in a cover all- tarp type shed, and it does get pretty toasty in there in summer.
 

schematic

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Re: 1998 Johnson 90 2 stroke timing procedure?

Most common way to fill those carbs with oil is to crank the engine without firming up the primer bulb first.
Second most common is to have hot and cold cycles of ambient temperature hydraulic oil from the reservoir. Therefore, its a good idea to store the boat with the oil tank cap loose to prevent this.

These pumps have few problems but get blamed for many others!
 

Lundman83

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Re: 1998 Johnson 90 2 stroke timing procedure?

Hmmmmm! I see! Mabey i will install a breather on that tank.
 

schematic

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Re: 1998 Johnson 90 2 stroke timing procedure?

take the cap off and pull the inside retainer off. Throw away the spring.......
 

Lundman83

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Re: 1998 Johnson 90 2 stroke timing procedure?

Ah! So it has a spring loaded breather in the cap? Excellent. I will do that thanks!
 

Lundman83

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Mar 27, 2013
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Re: 1998 Johnson 90 2 stroke timing procedure?

So i put #1 to TDC using a mag base dial indicator, and adjusted my timing pointer, which was 2 degrees off. Set the timing to the spec which i cant remember the number right now, gutted the breather on the oil tank.

Took it to the lake and cranked er over, and magic happened!!!
It actually started!!! No screwing around, flooding or running like crap!!!
She runs like a brand new motor now!!!
Ive never seen it run this nice! Perhaps the reason the last guy sold it?

Thanks a lot SCHEMATIC for your tip on the oil cap!!
 
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