87 volvo penta aq125 a wont start

[biggb87]

i have an 87 bayliner with the 4 cyl volvo penta aq125 a in it and it just wont start , and the thing i dont understand is that its getting everything an engine needs to start, its getting a nice blue spark and plenty of fuel and it still just wont start. ive done the plugs,cables,points,cond.,cap,coil,button,even had the carb rebuilt and it still just will not start.it gives a lil backfire out the exaust so we know its firing.what could we be overlooking or just plain ol doin wrong. thanks

[captmello]

Welcome.

It could be a number of things. Has it run before???

your ignition timing could be off, timing belt could have jumped a tooth, spark plug wires out of order...

[Hawk Eyes]

Just another idea. You have freash fuel or tried starting fluid?
I'd try spraying some starting fluid to see if its bad fuel. I had a bad fuel issue this year. It would spit and spudder but that was about it.

Let us know what you find.

[captmello]

Just another idea. You have freash fuel or tried starting fluid?
I'd try spraying some starting fluid to see if its bad fuel. I had a bad fuel issue this year. It would spit and spudder but that was about it.

Let us know what you find.

Some fresh gas should work for this just as well as starting fluid without the problems that starter fluid can cause. If you need starter fluid to start the engine, something is not right.

One other note, the carb on your engine has no choke so starting can be a little more tricky. A couple pumps of the throttle and leave it about 1/3 open during cranking.

[bobward737]

Let me add to the list.

Try the starting fluid first. If it starts and runs fine, than the accelerator jet in the solex in gummed up somehow. No big worries - I always start mine on starting fluid to make it easier on all parts involved.

Number two. Fuel pump. Have you disconn the fuel line from the carb and ported it into a cup or can while someone turns over the starter. Changing a fuel pump is very easy on a 125.

Three. Has anyone messed with the distributor or timing?

Four. Are you getting a good spark for sure? If not, a condensor is real cheap and easy to replace.

Five and MOST obscure. There is an in-line metal mesh kind of fuel filter in the fuel line just a few inches north of the tank. If it gets plugged or crushed over time like mine did , it restricts any fuel flow much above idle. REAL P.I.T.A., but easily removed. Just remove the fuel line from the tank end and run a coat hanger up the line till you feel it. I "hooked" my coat hanger and got it out after about an hour.

After all that, I do recommend an aftermarket fuel filter assembly that it easily changed. A good mechanic could properly install it to eliminate vibration and it ever coming loose as opposed to some shade tree mechanic throwing in a Dodge-style in line filter that is not properly secured to anything and then shakes loose and sprays fuel everywhere.

Hope this helps.

Bob

[occarvers]

Be careful with starting fluid. I have heard of intakes being blown off due to backfires! I would use carb cleaner instead.

[Hawk Eyes]

Be careful with starting fluid. I have heard of intakes being blown off due to backfires! I would use carb cleaner instead.

I agree with ya on that. You can lower the danger by not dumping a can into intake. I us a quick little squirt. If that didn't go, then I add a little more. I'v seen people hold that can for 3 to 5 seconds. Now that's over kill.