Mercury 110 Exhaust comes out the Tell Tale

[Mellonhead]

I have a Mercury 110 1976 SN 4391380 9.8HP. I put a new seira water pump kit in. I had the power head pulled to fix some other problems. I put new gaskets in between the powerhead, and drive shaft housing.

When I put is all back together, it doesn't pump water out the tell tail right away, and only trickles out at slow idle. When it isn't pumping water when first started, exhaust comes out the tell tale. It does pump water pretty in gear at higher rpms. The motor starts and runs good.

Does this sound normal, or could I have a water cover or head gasket problem?

I put all new gromets and nylon washers on the water lines?

Thank
MellonH

 

[LongLine]

Re: Mercury 110 Exhaust comes out the Tell Tale

I too had a water/exhaust problem after I replaced the water pump on a ?76 9.8 hp. (note: my compression was 105 psi on both cylinders) A little exploring and blowing smoke through a small tube in the various water ports showed me there is a way for exhaust to get into cooling water.

When I blew through port at A, smoke came/out (down) B.

I figure the only thing preventing exhaust going the other way is that the water jacket must be kept full of water. i.e equalizing the pressure.

More exploring showed that I didn?t have the copper water tube aligned perfectly with the fitting on the bottom of the block.

Lower unit off again, rotated the copper tube a little then re-inserted it for a better fit. Now at idle, it?ll make any race horse proud.

Tom B.
(LongLine)

 

[Mellonhead]

Re: Mercury 110 Exhaust comes out the Tell Tale

Thanks LongLine.

Are both pictures through the exhaust cover? It looks like it.

I may pull the cover and look. I may have to get a new water tube because I stepped on mine and bent it not badly, and tried to straiten it. ThaT might be the problem too.

If I have order parts I may as well pull the exhaust cover and look. Gasket are cheap.

Your help is greatly appreciated and very helpful!!
Thank You!!

 

[LongLine]

Re: Mercury 110 Exhaust comes out the Tell Tale

Yes, both pix thru exhaust cover. Good luck with it.

Tom B.
(LongLine)

 

[chucks440]

Re: Mercury 110 Exhaust comes out the Tell Tale

On a related note...anyone have a link to the manual for replacing the impeller on the 110s? I just changed the one in my Mercruiser and now the old 9.8 needs a new impeller! Any help would be great! Thanks..