Perfect 9.8 merc "tings"???????

[jbjennings]

My 1972 9.8 merc has had a new complete water pump kit, new lower unit seals, great gears and clutch dog, and finally, it runs perfect and throws a nice hard stream of water even at idle. I have even repainted and clearcoated it. There is only 1 ever-so slight problem that baffles me---When running wide open, it makes a very quiet ting--------------ting----ting-------------------------------ting sound. It is kind of like lightly tapping a glass with a spoon or something. It sounds like it comes from the powerhead. It runs great--smooth acceleration, incredibly easy starting when warm, great top end speed, etc. Is there anyone that has any idea what this could be based on my vague description of the sound? I am thinking that maybe one of the recoil lever "thingy's" may be tapping the flywheel??? Or could one of the pistons be slightly scuffing the cylinder? It is an intermittent noise with no pattern and a very quiet tinging that most people probably wouldn't notice but it scares me. Yes I'm paranoid but am just curious if some of you experts might have a clue.
Thanks,
JBJ

 

[Laddies]

Re: Perfect 9.8 Merck "tings"???????

Re: Perfect 9.8 Merck "tings"???????

If the small wave washer on one of the pawls is missing that the exact noise they make at WOT, the only other thing that comes to mind is to much spark advance causing a ignition ping

 

[jbjennings]

Re: Perfect 9.8 merc "tings"???????

Thanks Laddies,
Will check those pawls for the washers. If one's not there, I will probably have to then ask someone about how to retard the timing, as I have never done that before...
thanks again---you sure know your mercurys!!!!!
JBJ

 

[jbjennings]

Re: Perfect 9.8 merc "tings"???????

Well,
It's not the pawl washers. So....How does one retard the timing on the rascal?
Also, could the tinging sound be caused by using unleaded gas in something that was probably meant to run leaded fuel in? Could I just add some of that leaded fuel additive to see if that would help? Or should I just leave it alone and let 'er ting?
JBJ

 

[Laddies]

Re: Perfect 9.8 merc "tings"???????

Theres a philps head screw with a 3/8 nut locking it that you lossen and trun the screw in to retard the spark it should be 34 degrees BTDC, if it's alright go back to the starter pawls with the engine running there are 2 ways to tell run it with out the starter(use a rope on the flywheel) or with care running a WOT put the starter cord just enough to make the pawls ting and release it ifthe ting that you have goes away momentarly then it's a pawl

 

[jbjennings]

Re: Perfect 9.8 merc "tings"???????

I'm a bonehead! Should have thought of that---will run it without the recoil and see if that's it for sure before I go messing with the timing. I'm too scared to pull the cord slightly to slip out the pawls a little---I'm prone to disasters.
thanks,
JBJ

 

[jbjennings]

Re: Perfect 9.8 merc "tings"???????

Well, I ran it today and it didn't ting.
However, the darned thing takes about 15 pullls without doing anything and then all of a sudden, cranks up and runs fine. When cold, it's hard as heck to start, when warm, you can crank it by barely getting the pistons moving past TDC (about an 8inch Pull) and it runs beautifully. Let it sit for an hour or so and same thing, hard to start. I'm thinking the only answer is a carb rebuild but would like to know, if anyone does, why it would run so great and be so easy to start when warm, but not at all easy to start when cold. I like to know what I'm trying to fix in the carb. I'm accustomed to outboards running crappy period when the carbs are dirty. By the way, I did squeeze the primer bulb until firm before attempting to crank it. I did not squeeze the bulb after running it and letting it sit for about an hour and it was still hard to start. Any ideas on what part of the carb is dirty to cause this? Also, is there anything in this old '72 mercury 9.8 carb that I need to be careful of when taking the carb apart?
Thanks,
JBJ

 

[Laddies]

Re: Perfect 9.8 merc "tings"???????

It sounds like the idle tube is dirty in the carb or the float level is to low so pay speical attention to both when you clean the carb

 

[Chinewalker]

Re: Perfect 9.8 merc "tings"???????

Make sure the choke is closing FULLY when actuated. Not uncommon for the choke linkages to wear on those older Mercs, to the point where it really isn't choking much - more like only having one nostril plugged up...
- Scott

 

[jbjennings]

Re: Perfect 9.8 merc "tings"???????

thanks guys,
Will post back when I clean the carb and solve the problem. This is a sweet little motor and definitely appears to have very low hours. I'll post a pic of it running when I finally get it really right.
JBJ