Timing at WOT is that really needed?

That was a teaser, I know that it is needed, but while you are here, please keep reading?

I have been working with the timing on the 1988 GT200, the first time out I had a 4 blade 26 pitch prop, set the motor at 18 BTDC per the Clymer?s, then later on looking around I found a sticker that reads 16 BTDC, on top of the air box. The service manual reads as the Clymer?s. So which do I use?

I did reset the timing to 16 BTDC with a Raker 3 blade 24 pitch, the motor was not as labored as the earlier outing.
Without stopping my train of thought that I have at this moment, I am thinking that I have read somewhere that boat NOT be restricted while making these adjustments, at 4500 to 5000 rpms with a Raker 3 blade 24 pitch prop, the boat is moving around 50 to 55 MPH, I just can?t see me hanging on to the boat with one hand and the timing light in the other glancing around for timing marks.

So that brings me to my next question, do I need to have the test prop that is mentioned more than once in the manuals (Factory & Clymer?s)?
I am thinking that once I get through the WOT timing set, then move on the idle timing set, I will be at a 100% great running motor.

Re: Timing at WOT is that really needed?

I suppose I'd do what the stick says on the motor, unless the part came from another engine or something, perhaps someone that knows your engine more can help.

Here's what I do for WOT timing setting, most here will probably disagree with the method but I find it much more accurate than trying to set the timing by just cranking the engine and not starting it.

Disconnect the timer base linkage from the throttle arm linkage so you can adjust the timing without messing with the carbs and causing it to drink more fuel. Start engine, muffs or in water, move timer base linkage to it's stop (full wot stop) and check it with a timing light. This will show you your WOT full advance timing without going 60mph down the lake. Please note the rpms will go up on the motor but it shouldn't rev too high. Also, do it long enough to get it done then put the timing back down to normal idle settings. Local mechanic told me about that one and he uses it all the time.

Re: Timing at WOT is that really needed?

Your aftermarket book is refering to a standard 200/225. The 200 S model is different and 16 is correct as long as youre using the factory stock heads.

Now this is assuming you always run the airbox cover on, use fresh 87 octane, Champion plugs and target 5800 rpm.

Re: Timing at WOT is that really needed?

I really need to add that I tired to used the driveway method of setting the timing using the TOP SECRET method, that was before the finding the orange/blue wire around the #3 spark plug wire, so I just went to the water to set the timing. I do have a "S" model- J200STLCCM. My factory service manual (P/N 507664) states as well (unless I overlooked it) 18 BTDC.

I should try that again, that would make the trip to the water just set the idle timing at 6 ATDC along with the rest of the LINK & SYNC stuff...

Re: Timing at WOT is that really needed?

Dhadley said:

Your aftermarket book is refering to a standard 200/225.

Click to expand...

I am guessing that you missed the following:

http://forums.iboats.com/showthread.php?t=421041

I getting ready to head down to the water and check and set the idle timing...

I'll follow up the running conditions in the morning.

Thanks