Ignition timing specs volvo penta aq125a

Cjp13021

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May 25, 2021
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Changing the timing belt on an 84 volvo penta aq125a ..have all the pulleys lined up with their correct marks …haven’t tried to fire it yet …just trying to figure out what the specs are for the ignition timing ..can’t find it anywhere …and also the firing order …It’s 40 years old and the marks were off so I’m assuming as this belt stretched someone adjusted the rotor points a tooth back or forward …trying to figure out where the points should be with timing top dead center ..anything helps
 

kenny nunez

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Jun 20, 2017
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If you have a new belt from Volvo it will have yellow marks that line up with the marks on the sprockets. Remove the spark plugs after the belt is installed and turn the engine by hand around enough revolutions where the marks will work themselves back to where you started. This certifies that the belt is installed correctly. Sometimes it may take a few tries. It takes around 25 complete revolutions to bring the marks back.
1342 is the firing order. Points .019. Base timing 6-8 degrees.
 

Cjp13021

Seaman
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May 25, 2021
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So it’s running pretty good actually better than ever starts first turn…according to what I have looked up the idle ignition timing should be 6 degrees at 6-700 rpm’s and 32 degrees at 4200 rpm’s ….right now I’m at 12 degrees at idle but I’m idling at 1200 rpm’s ..and I’m at 35 degrees at 4200 rpm’s …I can’t adjust the distributor cap anymore without it farting and carrying on…I’m thinking carb needa adjusting?
 

kenny nunez

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You need to clean the carburetor. Most times the gaskets are reusable
if this is a down draft carburetor. The idle metering screw is always 1.5 turns from seated. Most times 1-1.5 turns on the stop screw. Anything more than this is not right.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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If you can't idle down, agree with Kenny. Service the carb
 

Cjp13021

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May 25, 2021
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It idles down , a thread I read said it should be 1100 rpm’s when in neutral and 700 rpm’s when in idle gear …I’ve been doing it in neutral not in gear so that may be my problem?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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It idles down , a thread I read said it should be 1100 rpm’s when in neutral and 700 rpm’s when in idle gear …I’ve been doing it in neutral not in gear so that may be my problem?
No, it should idle at 700 RPM in neutral and about 650 in gear
 

Cjp13021

Seaman
Joined
May 25, 2021
Messages
52
This site has a bunch of different answers for what it should be in neutral and I only have the workshop manual so wasn’t sure. It idles down to about 700 when I put it in gear at idle speed. I have all the specs for the carb so I’ll see if I can get it right by adjusting it. If that doesn’t work I’ll take it apart and clean it. This is in neutral as it is now sounds pretty good so I don’t think it’s too far off. Thanks for the help.
 

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