Total Advance Timing Question.

[stroker]

WHAT TECHNIQUE IS BEST FOR SETTING THE TOTAL TIMING IN ON A MERC . AND HOW DO DO THE PROS DO IT?INITIAL TIMING AT IDLE IS EASY ,BUT WHAT IS THE ACCURATE WAY TO DO IT FOR THE 7-8000RPM BLASTS WITHOUT SITTIN ON THE BACK OF THE BOAT WITH A TIMING LIGHT. LOL

[Jay Smith]

Don't know about the pro thing but I remove all spark plugs except #1 and I leave it hooked up with the timing light hooked up to it and the other plug wires grounded to either the block or a spark tester, with the key on and the fuel pump off ( if so equipted ) with the throttle in the wide open position I turn the motor over and over and this signals the # 1 plug to fire showing me what the top side , big end timing is. As far as the initial timing you would let the foot feed go back to the idle position and this should relay you the initial timing marks !

Jay @ JSRE

[us1]

Hey Jay I'm building that timming pedal to go out and test with.

[Jay Smith]

John ,

Remember what I told you when the tec. guy wants to know what the second foot feed is tell him it's a clutch ! LOL.............

Let me know if it picked you up !

Jay @ JSRE

[us1]

Ok, its pick up or blow up, either way I'll call you:D

[stroker]

OK,THIS MTR IS 2.5 EFI ,SINCE IVE OWNED IT IT HAS ALWAYS HAD A SYMPTOM OF NOT WANTING TO START UNLESS THE FUEL PUMP IS TURNED OFF,WICH IS ON A SWITCH.THIS IS ONLY AFTER YOU'VE BEEN RUNNING IT.IF YOU TRY AND FIRE IT UP WITH FUEL PUMP ON IT WILL TRY AN GO BUT UNLESS YOU GET INTO THE THROTTLE REAL FAST IT LOADS UP AND DIES.ONCE AGAIN IF YOU RESTART IT WITH THE PUMP OFF AND TURN IT ON AFTER A SECOND OR TWO, DOES FINE.WAS WONDERING IF THERE IS SOME INTERNAL RELAY THAT MAY NOT BE WORKING OR IF ITBSOUNDS LIKE AN INJECTOR PROBLEM,TO ME IT ACTS LIKE ITS GOING INTO CHOKE MODE EVRY TIME TO TRY AND FIRE IT. ANY THOUGHTS.? THANKS

[Jay Smith]

Stroker ,

I had a super stocker customer that had the same problem. It can be several problems , first you will have to establish whether it is a leaning or a riching condition. I would check my fuel filters first thing , you did not tell me whether it was a center horn motor or not so I will assume it is. The in line filter that is furnshed with the motor is a Kinsler micron unit and will plug VERY easily. Change it out to a 33093 WIX and at $ 6.00 I would change it often according to use. ( once a month in heavy service ) That may be a fix if it is a leaning problem. If it is a rich problem you may have a leaking injector, when the key is shut off you may be dribbling into the intake areas causing a rich condition only when a restart is tryed. Next look at the orficed Tee below the regulator and across from the fuel rail the line across from the fuel rail has a VERY small hair like opening , that is to allow pressure to slowly bleed back tru the return line so the fuel pump can start without a load against it. If this SMALL opening is stopped up it will not allow fuel pressure to deminish and it wll keep a constant pressure on the injectors seat and if one is a leaker it will amplify the problem along with causing astrain on the start up of the fuel pump.

Hope that helps but that is several things I would do first .


Jay @ JSRE

[stroker]

I ENDED UP INSTALLING A PAXTON EFI PUMP I CONVIENANTLY HAD, AFTER THE WELDON PUMP THE MTR WAS PURCHASED WITH TOOK A DIVE.ALSO HAVE RATHER LARGE PAXTON INLINE FILTER.THE LEAKEY INJECTOR SOUNDS MORE LIKE THE CULPRIT.THERE IS SEVERAL OF THESE FUEL INJECTION PLACES AROUND HERE ,PREDOMINANTLY AUTOMOTIVE,ARE THE INJECTORS SOMETHING THAT THEY CAN PULL A PART # OFF OF AND SPEC OUT AND CHECK OR WOULD YA TAKE THEM TO LOCAL HIGH SCHOOL MERC MECHANIC,MY POINT BEING LOCAL MERC SHOP NOT VERY VERSED IN THIS I AM SURE.

[us1]

Don't mean to but in Jay but I’ve had this problem before. You might want to try this too. Its simple, there are two yellow with a red strip wires on the starter solenoid. One runs into the wiring harness going up in to the boat and the other run into the EFI harness going to the ECU. Disconnect the yellow and red wire going to the ECU. This is the choke wire. Ever time you go to start the motor when hot it is choking it and flooding it. Turing off the pump is defeating the choke. If this works for you just put a push button on the dash connecting this wire to 12 volts only when you need it.

[Jeff_G]

Stoker it depends on which year and model you have. On most of the motors the total advance timing is set at cranking speed and it retards at about 2 degrees at wot. ie cranking speed timing 18 wot 16 degrees. Some motors are set at cranking speed period like a Pro Max 225. If you have a motor that has a cranking speed setting with a wot retard just set the timing at cranking. If you want to check it a timing light is the only option. Just set it with the boat on the trailer and only the lower unit in the water.

[Jay Smith]

DO WHAT ??????????

Jay @ JSRE...

[Balzy]

I grounded all the plugs with a hillbilly spark tester. (1 tie wrap around each bank of 3 plugs with a ground wire strapped in with them, do the same thing for the other bank) Put the tming light on #1 plug wire and cranked it with a fresh battery and the throttle WOT. Oh yea, I did unplug the fuel pump too. Reading came in right @ 25 BTDC. Did I do something wrong or will this work too?

[Jay Smith]

That will work just as well Mike, some of the newer motors I'm told by my dealer friends need to have ALL the plugs out to let the motor achieve the correct 500 or so RPM's to be checked.

THe way I described for Stroker works fine for the 2.5 Hi Per center horn motors that has none of the emissions crap on it.
(spark advance boxes ) .


Jay @ JSRE

[BayouRat454]

will this procedure you discussed setting timing work the same for a 89 225 looper? thanks

[Balzy]

Then I am ok with the way I did it. Good deal.:D :D :D

[Jay Smith]

I'm not versed on OMC's but if I had one that didn't have the spark stabilizer box on it and didn't require a method of timing that was indeginus to that make and model I would feel comfortable doing it the above posted way. Maybe some of the guys more familiar with the 89' 225 looper OMC in question will speak up and reassure you of the procedure .

Jay @ JSRE