AQ125a Timing

dexterm16 · Aug 15, 2012

I have replaced my timing belt but need to time with a gun. I have never done this before- can anyone please explain to me the process?

rav221 · Aug 15, 2012

Re: AQ125a Timing

Here's a link to a video explaining the process.....hope it helps.

http://youtu.be/FZxsp7S7ZhQ

Don't worry about the part about changing the springs in the distributor, you won't have to worry about that.

dexterm16 · Aug 15, 2012

Re: AQ125a Timing

I appreciate all the help RAV221. I am a handy man but had no idea the effects that the timing had on how the engine ran. If was my understanding that if the engine was running it was timed and all the pulleys were properly aligned and if the engine wasn't timed it would not run at all. It is amazing how the position of the distributor changes the idle. thanks again

rav221 · Aug 15, 2012

Re: AQ125a Timing

For your AQ125A, I believe your ignition timing is 6 degrees @ idle (around 600-700 rpm) and 32 degrees at 4000 rpm. Double check that with your Spec. manual. I'm not sure what year your engine is.

RogersJetboat454 · Aug 15, 2012

Re: AQ125a Timing

Dex,
We're talking about setting the ignition timing, and not setting the cam timing (lining up the pulleys after the timing belt replacement), right?

rav221 · Aug 15, 2012

Re: AQ125a Timing

RogersJetboat454 said:
Dex,
We're talking about setting the ignition timing, and not setting the cam timing (lining up the pulleys after the timing belt replacement), right?

The way DEX explained it in a previous thread, he changed the timing belt already. The boat is running and apparently sounds OK at low speed, but he can't get any power. I had explained the importance of checking the ignition timing after a timing belt change. Just trying the obvious/easiest solution first. He was unsure of the process to check/set the timing.

Maybe you have another idea I'm missing. Here's a link to the original thread...

http://forums.iboats.com/showthread.php?t=572824

RogersJetboat454 · Aug 15, 2012

Re: AQ125a Timing

rav221 said:
The way DEX explained it in a previous thread, he changed the timing belt already. The boat is running and apparently sounds OK at low speed, but he can't get any power. I had explained the importance of checking the ignition timing after a timing belt change. Just trying the obvious/easiest solution first. He was unsure of the process to check/set the timing.

Maybe you have another idea I'm missing. Here's a link to the original thread...

http://forums.iboats.com/showthread.php?t=572824

Was not aware of the other thread.

Dex,
Check the ignition timing. If it's off a few degrees, adjust and see how it runs. If it's dramatically off, or adjusting to spec doesn't seem to help, you need to take another look at the cam timing.

A handy guy like you would also be well served if you picked up a copy of the factory service manual (avoid the urge to buy a Seloc or Clymers).

bruceb58 · Aug 15, 2012

Re: AQ125a Timing

Did you happen to change the points as well? No matter what, you should check and adjust your dwell before adjusting timing. You want to use a dwell meter to do that...not gapping.

trophy boat · Aug 18, 2012

Re: AQ125a Timing

Getting the belt pulleys lined up is badly described in some of the manuals. I once got it installed being a couple of teeth off and it ran great at low rpm but wouldn't go over 3000 rpm or 12 mph. Once I figured it out it ran fabulous.
Also make sure you test the advance as these old springs can break or get rusty and stuck. Once you get it timed rev up the engine and see that the timing advances up to 30 degrees. Without the advance you will get similar issues.

dexterm16 · Aug 18, 2012

Re: AQ125a Timing

what are you using to time it up ? The gauge on this motor is on the motor and not the pulley. What mark do you line up on the pulley to the gauge? How do you adjust the distributor cap?

Nhpatriot · Aug 18, 2012

Re: AQ125a Timing

When the new belt is installed it has lines that you should align with the dimples in the timing gear and distributor gear. the lines on the belt don't really matter they just help you make sure everything is correct.
Use a manual! My Seloc worked just fine for this motor.
Notch in valve cover, dimple in cam pulley,
notch in stainless bracket behind distributor pulley and dimple in distributor pulley,
0 degrees on timing bracket and dimple in crank pulley
All have to align with piston 1 at TDC compression stroke.

AQ125a Timing

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