AQ125A won't fire

Before I begin, let me say I have looked in the forum and have found a ton of info on this subject. I am just a backyard mechanic, if its fairly simple to do, I'll try it myself to save money. So far I have $40 bucks into this project, but I think it beats $80 an Hr. plus parts at the marina. Here goes...
I bought an 82 Bayliner with an AQ125A/270 Volvo Penta. Guy said it ran, but a little rough. From what i have checked into so far, I know they are cold blooded anyway. He put new plugs and wires in it and fixed a crack in the water manifold from not winterizing. O.K, no biggie, I bought it as a fixer upper anyway as long as the motor was solid, and it was.
First time out I adjusted the carb to manuel specs, cleaned out carb with spray and it ran great. Next time out to check an outside transom seal I replaced, it would nt run. Took it home to fiddle around, wiggle wires, clean points and distributor cap, no dice. Replaced points and rotor, no dice again. Replaced condenser, same result. Just not getting spark at the plugs.
Now I am leaning toward the coil. It seems to check out though with the ohm meter, primary is strong and secondary is about a quarter strength. I dont have the specs though. Do these just go out? or can they work intermittently, because it fired up in the driveway a couple times then nothing again. Now that I write this I just realized before when I checked for spark with the plug out, puffs of gas came out the cylinder and last night it did nt when checking again.
Should gas be spraying into the carb when trying to start? I know the tank is full. Anything about the coil will be usefull info. I have been at this for 4 days now. Am I gonna have to take it to the shop after all? These older motors seem so basic compared to todays, how tough can this be? I am going nuckin' futz here !! Please help ! The holidays comeing and I would like to use this boat. Thanks in advance.

Re: AQ125A won't fire

I'm no volvo guy, but points is pretty generic. Place to start is the coil. With the key on, engine off, is there power to the plus side? Yes? move towards the distributor. At the negative side of the coil, remove the tach wire sometimes the tach shorts out. Temporarily remove the one going to the distributor. It should be insulated all the way to the points. With your ohm meter, with the points open, touch the points where the wire connects. is there any continuity to ground? Base of the distributor will work. There should be none. If there is, points are shorted or improperly installed. repair them. Put the distrib wire back on the coil. No power to the coil Plus side? Start towards the starter. One of the wires puts 12 volts to the coil when starting. The other is a resistor wire thats drops the voltage to 9 so the points don't burn up. Could be there is an issue at the starter or in between (burned/rubbed through wires, corrosion, etc) Start with one of these scenarios and see what you have. If all this checks out, it has to be in the cap/rotor.

Re: AQ125A won't fire

Thanx for the quick reply. I will slow down, I am pretty frustrated. I will try that and get back to you later today. I am 12 miles from the boat with no computer access there so please bear with me.

Re: AQ125A won't fire

I have checked the coil. One side says 12 + volts the other a lot lower. I checked the points gap, all is good there. Tested the dist. wire test good. I guess I will replace the coil. $ 50 Bucks. Can I use a car coil as long as it matches? It may be cheaper.

Re: AQ125A won't fire

That is not how to test a coil. In fact those numbers are normal with the key on. Troubleshoot components one at a time before throwing parts at it.

Points gap is not as important as the dwell angle or percentage. The points gap get it close, then adjust the gap to get the dwell figure correct.

Testing a coil is easy and kind of fun, and you can probably do it in place. You will need a jumper wire to go from the battery positive terminal or any 12 volt source. You need another jumper wire to connect to the coil's negative terminal at one end and be able to ground the other end repeatedly. You remove the big coil wire at the distributor and put a screwdriver or spark plug in the end of it and have it close to a ground. Remove any wire harness connections at the positive and negative terminals at the coil. When you are ready to test then connect the 12 volt source to the coil positive terminal. Clip the other jumper wire to the negative terminal and hold the other end ready to ground it. Ground that negative coil wire, hold it for a second then unground it. That should generate a spark fom the big end of the coil to whatever ground it is close to. Ground and unground that coil negative wire and you should see sparks each time.

Re: AQ125A won't fire

Thanks guys. It was the coil. I used the jumper wire test and got no spark. Bought a new one from autozone. It starts but now i have to mess with the timeing.