The stream is so broken on this thing I am guessing prostate problems

[Bullie]

I picked up a Mercury 110 9.8 HP I think it is a 1978 a couple months back. It had a bad switchbox and lots of the insulation on the wires was cracked and falling off. I also cleaned the carb and put in a kit and got it running well. I replaced the water pump impeller as the stream was sporadic. After replacement the stream still wasn't steady. I have taken the LU off several times now and inspected the pump and copper input tube. I replaced the plastic outlet sleeve as it was a bit flared but the intermittent stream persists. I used the water hose to push water through and it comes out in a steady stream. I also blew it out from both directions with my air compressor. Still the same broken stream. When I had the LU off I clamped it in my drill and submerged the pump in my barrel and it pumped a good stream of water out of the sleeve. I am at a loss. The temp hovers at around 140 degrees after warmup at idle. Any ideas?

http://vid230.photobucket.com/albums/ee260/Bulliedawg2/Outboard/20150617_084145_zpsfc8evbgx.mp4

 

[Texasmark]

Well looks like you covered the bases pretty well. The 9.8 may not have a thermostat but hovering around 140 suggests it does. 143F (start of opening cycle) is a popular pellet temp for Merc. Stats. Follow the hose back from your outlet on the cowling and tell us where it originates. Then get us a picture of the rear of the block as close as you can get keeping it focused and showing the whole rear of the engine at and above the cowling. The distance you used in your video is fine, just move around to the rear and shoot from there, everything else as you have in the video. A picture will do.

I just viewed your video and first of all you have adequate water over the pump whereby it should be able to suck. What I think is wrong with your assessment is you have the engine in gear creating a lot of turbulence, not only in water moving about in a confined space, but in bubbles that compress whereas solid water doesn't. The stream seemed to be rythmetic adding to the suggestion that turbulence was causing the erratic stream.

What does it look like in N with that amount of water in the barrel and no bubbles? Only other thing while waiting on your reply to the above is whether or not there is another gasket on the water line between the block and the copper water tube. A parts diagram from a manual would help you determine that. On that age of an engine no telling the history. Seloc manuals are for sale or can be onlined here on iboats.

 

[GA_Boater]

What happens when the revs increase?

 

[Bullie]

I will get a picture. It pumps the same in gear or out. I was running it in reverse to get a few more rpms...only a few... to check to see if the temps would move towards an overheat situation.

GA_Boater when the revs increase it does pretty much the same thing.

 

[GA_Boater]

I asked because mine has a steady, weak stream at idle and as the revs go up it turns into a racehorse stream. Try it in neutral and give it some gas, a good fast idle about 2000 RPM if you can judge. Not wide open, it's not good for the motor in a barrel.

The motor is shaking quite a bit in the vid. That could cause the broken stream, too.

 

[Bullie]

 

[racerone]

It should pee a steady stream.----Try it on a boat.----Or look for that melted over washer under the power head.

 

[Sea Rider]

Sometimes it's better to change complete water pump kit as opposed to just the impeller. Was the current impeller liner in good shape, that's not marked with tiny rotational lines ? Those lines reduces top pressure a bit.

If that engine has not been correctly flushed after boating specially on salted waters, internal water passages might be slight clogged at the peeing area and difficults peeing like a teenager. Squirt with red cannula an overdose of W40 through peeing port, let soak for some minutes, test engine at open waters and check.

Happy Boating

 

[MTboatguy]

On my 9.8, it always pees better in the lake than it dos in the barrel, drove me crazy and finally I decided to head out for a day of fishing and it performed just fine with no problems and no overheating, it does not pick up the same amount of water in a turbulent barrel that it does in open water.

 

[Texasmark]

On my 9.8, it always pees better in the lake than it dos in the barrel, drove me crazy and finally I decided to head out for a day of fishing and it performed just fine with no problems and no overheating, it does not pick up the same amount of water in a turbulent barrel that it does in open water.

As I said earlier, before you get too worried about it, get it on the water with your temperature monitoring device that you are currently using and test it there. You can't tell anything in the barrel necessarily. The hose comes straight off the water jacket and I see no thermostat to get in the way or cause problems if stuck shut, or the pee having to wait on the stat to open to pee like on some of Merc's engines.

If you get worried about powerhead temps, the OT senser on my 90 was 195F with a stat opening of 143. So with the numbers you posted, you have plenty of room before you need to get excited about a problem.

 

[Bullie]

Thanks for the info guys. I haven't put this one in the water yet. Maybe I am just being overly cautious. It just doesn't pee like the others.

 

[Texasmark]

Thanks for the info guys. I haven't put this one in the water yet. Maybe I am just being overly cautious. It just doesn't pee like the others.

Put it in the water, test it, then worry about that. Lots of different passages and arrangements.

 

[Bullie]

I put the little 9.8 on the boat yesterday and tested it out. Seemed to do great and gave a steady stream with a few rpms.

 

[444]

FWIW, my mercury 175hp, about the same year as yours, has an abysmal pee stream at idle/low revs as well. Always has been like that. Picks up to a steady stream when out on the water. Never has had the race horse pee stream like my old 86 mercury inline-6 did, as I too was concerned when I ran the engine in the driveway.