9.8 MERC will not start

[twist]

Have a 9.8 mercury 110 serial no. 3737097 that will not start. Have had it into two shops and they've both changed plugs, and points. Last shop said that there WAS spark but it still would not start even when they shot some gas right into the cylinder. Thought that there was some internal problem .... duh. Any ideas about how extensive my problem might be or what I'm up against?

 

[dmessy]

Re: 9.8 MERC will not start

Hi Twist,I'd be wary of a shop thats only given you the advice you metioned.<br />If you have spark(at the proper time, ie:timing) and fuel via carb or directly sprayed, the only other things you need are exhaust and compression. The exhaust is just a port so you can rule it out. <br />You need to check compression. A quick, seat of the pants method is to hold your thumb over the sparkplug HOLE and turn it over(make sure the plugs are in the wires and grounded to block b4 turning it over). You should have enough compression (around #100) to blow your thumb off the opening. If the compression is low you are looking at a bore/hone/piston, pretty expensive.<br />I really doubt that is your problem as these motors are bullet proof. I once ceased mine, let it cool, fixed the cooling problem and it has run ever since even with low compression #s. Good luck and let us know how it turns out. I highly suspect the engines timeing is way off.

 

[plywoody]

Re: 9.8 MERC will not start

Did it all of a sudden stop starting, or is this a new motor to you?<br /><br />I agree with the previous poster that I would not trust a shop that gave you the advice it gave. Check the spark, compression, and all fuel connections and go from there. Generally starting problems are simple problems, unless something else happened to the motor previously. I would not start messing with the timing or anything else until I was sure I had good spark, adequate compression, and fuel. It's the old "If you hear hoofbeats, look for horses, not zebras"<br /><br />John

 

[twist]

Re: 9.8 MERC will not start

It is a new motor to me, but it was running last year. The one shop I took it to is a marine motor shop, not Mercury outboard ... have to go a quite a few miles to get to a Merc outboard repair shop, but their concern was that it didn't fire with gas in the cylinder and spark. The mechanic mentioned possible "reed" problem? They are very busy with winterizing at this time of the year, so maybe they just didn't want to deal with it.

 

[plywoody]

Re: 9.8 MERC will not start

Have you checked anything yet, like compression? The thumb test as earlier described is adequate for these purposes.<br />Tell us what precisely you have checked so far, and how you checked it. Re: spark, compression, fuel.

 

[aijmst]

Re: 9.8 MERC will not start

sounds as if piston rings could be stuck alowing fuel to leek past piston and out of exhaust. if this is the case, you will have no crank case pressure and little or no comprestions and it will never start until they are freed up.

 

[plywoody]

Re: 9.8 MERC will not start

It could be any number of things, but it is impossible to know without some information so we can rule things out and get closer to what the problem may be. Speculating about reeds and piston rings and fuel lines and who knows what all is kind of useless until we get some information.

 

[BassAddict]

Re: 9.8 MERC will not start

If other suggestions fail, try popping the flywheel off and checking for a sheared off key which would throw your timing way off. Might have had a quick stop(gulp of water?)......happened to me once on an old Merc.