Volvo penta aq131a- 275 drive---trouble timing out the engine

[taejeron4]

Okay, in the past ive had to thank many..capt Ron etc....my mind is blown on this

Trouble timing out the engine...
All 3 marks on the engine set to spec marks
no 1 on compression stroke
rotor set and pointing at the number 1 spot

checked timing with all marks set to 0----wont start--checked timing in the area it will start and is sitting 10 degrees atdc.
engine starts and idles but when raising the rpm it backfires/pops and dies
will only start at the 10 degree atdc point.

need to get it to its spec point of 6 degrees btdc so I can check it at 4400 rpm in which is supposed to be at 32-36 degrees atdc.

have pulled the distributor, tried to retard 1 gear and get nothing but popping thru the carb.

reset all to original spots..again only runs in the 10 degress atdc spot....try to adjust and retard and it dies.....

anyone got a stick of dynamite?

Mike

 

[frank246]

Did you check 0 tdc on the piston or balancer?

 

[taejeron4]

we checked it with the spark plugs out..on compression....also all mfg marks are set to the mfg set points

 

[Fun Times]

I just read an idea you could try doing to see if it will help ensure your plug wires are in the correct order etc. etc. (See copied quotes below).

Also do you have a dwell meter to see if your dwell setting is around 62 + or - 3* at cranking speed/running? Having the dwell set/within range helps make all this just that much easier to contend with. Good luck.

AQ131A timing procedure:
I'm getting ready to fire the old girl up for the first time after installing new points, plugs, rotor, rotor cap, timing belt, tensioner, exhaust manifold, sparkplug wires alternator and so forth.

The engine presently sits at TDC on the compression stroke with the cam pulley marker pointing at 12:00 on the head, the crankshaft pulley is zero degrees on the plate and the rotor is pointed at cylinder number one.

My assumption is that I need to set the timing to 6 degrees BTDC initially to get it started.

1. I'm going to hook up my timing light per instructions and hand turn the engine until I get a flash. (sparkplugs are out)

2.Then I will loosen the bolt at the bottom of the distributor, repeat the rotation, and rotate the distributor until I can get the flash and the 6 degree mark to line up. Then tighten the distributor bolt.

3. Then, install the plugs, open a beer, turn the key and hope for the best.

4. If it starts, then I should loosen the distributor bolt slightly and turn it until I have the timing mark and light lined up at idle speed.

Beyond that I'm not sure what to do. Does this procedure sound about right?

Yes, sounds about right.

Mike, I often do something very similar. I'll bring the crank around to 6* or 8* BTDC, and then with ignition ON, I will rotate the distributor against normal rotation until I get a spark from the coil via a spark plug to Negative (it can be directly from the coil via a spark plug cable and spark plug)

However, while this is usually good enough to fire on, it is NEVER accurate enough to run on! So you will want to set BASE advance ASAP.​

What you may also do, is use your timing light and strobe this while you crank the engine over.
The engine does not unnecessarily need to run to set BASE (i.e., there is no progressive spark advance below 1k rpm.)
So basically, 200 rpm will get you a BASE reading.​

​

 

[jerryjerry05]

What condition are the pullies?
They need to have sharp even edges, any corrosion?
The tensioner is it rusted?
Sounds like it's off by 1 tooth.

 

[bruceb58]

The distributor being off a tooth means nothing as long as you can rotate the distributor far enough.

Has the timing belt been changed recently? I would be more worried that would be off.