YAMAHA 80 4 STROKE 2003 MOD TIMING?

[tommynor]

HELLO I HAVE ONE YAMAHA 80 FOUR STROKE 2003 MOD.CAN ANYONE TELL MY WHAT THE TIMING ON THIS ENGINE SHOULD BE?<br /><br />AND TELL MY THE CORRECT WAY TO CHECK IT?

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

Originally posted by tommynor:<br /> HELLO I HAVE ONE YAMAHA 80 FOUR STROKE 2003 MOD.CAN ANYONE TELL MY WHAT THE TIMING ON THIS ENGINE SHOULD BE?<br /><br />AND TELL MY THE CORRECT WAY TO CHECK IT?

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[rodbolt]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

hello<br />my book only lists the F80 to 2002. post the model number. from 99-02 the spec is idle 5*ATDC plus or minus 2* ant wot is 20*plus or minus 1*. you can check it with a standard timing light as per service manual drawings and references.

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

thanks <br />rodbolt

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

hello now i have checked the timing<br />and this is the result<br /><br />cyl nr 1 : -5*<br />cyl nr 2 : the timing light was flashing but couldt se how many * it was becuse there where no marks there .. <br />and cyl 3 and 4 was the same couldt se anything on those to cyl ether<br /><br />is not the all 4 cyl supose to be the same??<br />or am i wrong??

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

???

 

[bigbrownbuku]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

in a 4 cycle 4 cylinder engine if all of your pistons are at tdc compression all at the same time you have a bigger problem then timing.

 

[rodbolt]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

tommy<br /> on that motor it uses waste spark. means that when 1 piston is at the firing position the second coil wire lead is firing another cyl on the exhaust stroke. the flywheel timing marks are for #1 cyl at TDC compression stroke. the piston will actaully be there twice at TDC. once at the compression stroke and once at the exhaust. I think the f80 fires 1 and 4 and 2 and 3 in pairs.hence the term waste spark. so 1 and 4 should show the same timing and if you index the flywheel for a TDC mark on #2 you will see 2 and 3 at the same place with a timing light. the light cant tell if its a waste spark ign or not it just flashes everytime it gets a trigger signal on the light pickup.<br /> so yes each cyl will spark at -5* btdc they will do it twice per evey 720 degrees of rotation. once on the compression stroke and once on the exhaust. takes 720* of crank rotation for each piston to go through a cycle of intake, compression, power and exhaust. commonly known as suck,squeeze ,bang, and blow. if all 4 happen at the proper time it hums like a mazda.

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

hello it seems like the coil signal from cylinder #2 and #4 are bad. becuse my timing light are flashing only sometimes most off the time is not flashing at all.i have tryed to remove the wires for cylinder #2 and #4. but then the engine want run. so the engine gets some signal from those 2 wires.<br /><br />and this is causing backfiring in my intak for carb nr #2 and #4 <br /><br />where is the signal coming from is it from the C.D.I?<br />could my C.D.I bee toasted?<br /><br />is it somting under the flywheel whoo control the spark ?<br />becuse my tach for RPM is not working either..<br /><br />any idea what could bee the probleme??<br /><br />THANKS FOR ALL ANSWER<br />BEST REGARDS TOMMY

 

[rodbolt]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

tommy<br /> do you have a service manual ? if you lost the signal on 2 and 4 odds are it would not run. the 2+3 and 1+4 cyl are on the same signal. I will try to look up the specifics. however you will need a manual and a peak reading voltmeter

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

I DONT HAVE PEAK READING VOLTMETER<br />IS POSIBEL TO CHECK IT WHIT SOMTHING ELSE?<br />IS IT SOME WAY TO CHECK THE SIGNAL FROM THE C.D.I TO THE COIL <br /><br />I THINK ITS STRANGE ITS ONE WIRE ON EACH COIL HO IS NOT WORKING PROPERLY<br /><br />CAN IT BEE TO WEAK SIGNAL AND WAY?

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

ANYBODY KNOW A way to check the C.D.I unit?

 

[rodbolt]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

tommy<br /> your going to have to find a service manual. the CDI can be checked for inputs and outputs. most likly the inputs to it are bad. two plug wires fire everytime. so if your getting correct spark on 1 odds are the signal is there for the other one. if not then suspect the trigger inputs. the only way to test them is with a peak reading multimeter and a service manual.<br /> the system fires both coils at one time, 1 and 4 and 2 and 3. if #1 fires #4 fires with it, when #2 fires #3 fires with it and when 4 fires 1 fires and when 3 fires 2 fires. . so now we are down to pulser coils or an ign coil. the CDI just reacts to trigger signals.resistance on the pulser coils is 495 ohms cyl 1,4 is w/r-b,cyl 2,3 is w/b-b. the tach signal comes from the charging system. if I get a chance ill try to look up some more specifics on the F80 tomorrow, if the pair of 8.1 mercs I am installing does not kill me .

 

[tommynor]

Re: YAMAHA 80 4 STROKE 2003 MOD TIMING?

i have now ordres online sevice manual from <br /> SELOCMARINE.COM<br /><br />but i am stil hoping to get som help from you becuse i am not so god to read wiring diagram<br /><br />....<br />is it any conection btween the tach and the ignition system?