timing on aq 125 a

[gord 495]

is it uncommon when setting the distributor on a aq 125 a volvo to have it at 20 deg btc at idle ? the book calls for 10 deg, but when i set it at that it runs rough. thanks

 

[Don S]

Re: timing on aq 125 a

Did you set the dwell on the points first? Are the points, condenser, cap and rotor new or in good condition (Looking good to someone that doesn't know the difference between good and bad doesn't count)<br />How long since last tuneup?<br />Did you try adjusting the carb?<br />Is the timing belt in good shape along with the pullies and tensionser.

 

[gord 495]

Re: timing on aq 125 a

the points are in decent shape, i set the gap at 16 thou, condenser and points were changed 30 hours ago, timing belt changed same time and the carb seems to be o.k. is the 20 deg btc to far off don ?

 

[Don S]

Re: timing on aq 125 a

Yes 20° is too much. Needs to be at 10° BTDC at idle.<br />When you say the points were changed 30 hours ago, was that Sunday you changed them??? Seriously, when (Month) was the points changed? They really need to be set with a dwell meter on any of the Volvo 4 cyl "rubber band" engines (4 cylinder OHC, with "Rubber" timing belt.), any engine for that matter, but the RB engines are very picky about dwell and timing settings.<br />Have you done a compression check recently?

 

[gord 495]

Re: timing on aq 125 a

that would be 30 engine hours ago don, as far as the dwell goes, no i didnt use a dwell meter when setting the points. i see now how important that stage is to use a dwell meter. could that alone cause my timing to be out that much ?

 

[Dunaruna]

Re: timing on aq 125 a

Your timing isn't out. You are adjusting it to be 'out'.<br /><br />What you need to do is find out why it's running rough at 10 deg.<br /><br />ergo, Don's questions.

 

[Don S]

Re: timing on aq 125 a

that would be 30 engine hours ago don

30 hours doesn't mean anything if the boat gets only 10 hours a year. With points, you need a NEW set every year to run properly. And yes it needs to have the dwell set as the feeler gauge method is only good for getting close enough to use the dwell meter. Dwell also effects timing.

 

[gord 495]

Re: timing on aq 125 a

i was asking before don about the exhaust sound comming from what sounds like the exhaust bellow that connects the manifold and exhaust pipe, i was wondering if maybe there wasnt enough water going through the exhaust, or could it be because my timing is that much out ? what do u think...i know it's hard to give advice when you cant hear it. and yes the points were changed this year, and like i ewas saying they have about 30 hours on them...but I'm gonna install a new set then set dwell.....thanks don

 

[Don S]

Re: timing on aq 125 a

Those engines have a tendancy to corrode away on the head around #4 cylinder. That would cause your exhaust sound. Read this post.<br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=24;t=014815 <br /><br />Good idea to replace the points and set the dwell then the timing. Bet you find it runs better. But it's probably not going to effect the exhaust noise.

 

[gord 495]

Re: timing on aq 125 a

i've replaced the exhaust manifold this year with an aftermarket manifold [ osco ] i believe. when i did the changeover i didnt notice any wear on the head, but i may look there again. this sound really has me baffled, sounds so much like exhaust yet i cant see any leaks at all or smell anything out of place. if it were # 4 port on the head, would i not see the leak with escaping exhaust ?<br />and one other thing, the sound starts at around 2000 rpm's and up, but only under load, below 2000 and it's nice and quiet.

 

[john crawford]

Re: timing on aq 125 a

Just learning this site. Can you tell me if an exhaust manifolfd is cracked, wil
the engine backfire out through a weak/pushed out frost plug, or does water and exhaust exit in common. Trying to figure out if there is an internal crack.
Sorry to butt in but i have not figured how to post a Q as yet. good lucck with yours. John, Regina Canada

 

[ENCMJB]

Re: timing on aq 125 a

is it uncommon when setting the distributor on a aq 125 a volvo to have it at 20 deg btc at idle ? the book calls for 10 deg, but when i set it at that it runs rough. thanks

Hi all. This is my first post on this site. I am having the exact same problem Gord is having. My AQ125A runs fine at 20 deg BTDC, but wants to fall on its face at 10 deg BTDC. I have new points, condenser, cap, plugs, and wires. I set the dwell with a dwell meter and it is at 60. (Specs is 62+/-3). I'm baffled. Any help would be appreciated.
Matt

 

[Don S]

Re: timing on aq 125 a

Welcome to iboats.
Please, read the archives and learn from them. Do NOT post to them.
If you have a question, start a new thread of your own. Don't just jump in on the end of a 4 year old post. After a couple of replies, your question will be gone and everyone will be answering the original posters question....... Again.