1999 9.9 johnson 2 stroke cooling

[6point]

Just changed the impeller but at the lowest rpm it only spits water from the telltale and is hot but any acceleration and it is normal at lake temp. I reversed the impeller with the exact same result. I can't recall what it was like before the change but only changed it because it was never done since new, however the original was like new condition. Suspect the pump but would like more info. The grommet to the outlet tube is fine.

 

[kbait]

Re: 1999 9.9 johnson 2 stroke cooling

I'd pull the thermostat, replace cover, and test it. If good, new stat. If not, post back..

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Thanks, I thought the same but nowhere in the service does it talk of a thermostat although cooling is with temperature and pressure. If you can direct me, please do. I will appreciate it.

 

[Rick.]

Re: 1999 9.9 johnson 2 stroke cooling

http://epc.brp.com/SiteMods/BRP_Public/BRP_Public_Login.aspx?ReturnUrl=/Index.aspx

Follow this link and you will find your thermostat, and all your other parts too. Best of luck. Rick.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Thanks a bunch Rick, located it in the schematics and will now get on it.

 

[Rick.]

Re: 1999 9.9 johnson 2 stroke cooling

Aren't I a wealth of knowledge? Your welcome. Hear is another link that is fantastic IMO. A must read for us 9.9 tinkerers. Rick.

http://www.sschapterpsa.com/ramblings/OMC/OMC info.htm

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Thanks for both sites Rick, have added to favorites. Removed the thermostat and thought I would just replace it rather than operate the motor first without it. I pinched the assembly together and tried blowing through it but it is blocked, think there should be some movement but I am no mechanic. The local marine store has a replacement but was wondering if the inner spring needs to be changed also as it looks like it may be the necessary part to open the diaphram. Your thoughts please.

 

[Rick.]

Re: 1999 9.9 johnson 2 stroke cooling

I believe they are designed to open at 140 F. What I would do is heat up some water and get it up to say 160 to 180 F. and then immerse the stat in the water. You will see immediately if it opens or not. If it does I consider it to be a good stat and re-use it. Hope that answers your question. Rick.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Thanks again,did as suggested and the pin slides out so looks like it is ok, now is it down to the pump or do you have another suggestion.

 

[bktheking]

Re: 1999 9.9 johnson 2 stroke cooling

The water shouldn't be hot, not from the telltale, mine is always cold and pressure is strong. Test with the stat out before putting it back in. You either have a blockage or a pump issue still.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Ok will try it without first then and go from there.

 

[Rick.]

Re: 1999 9.9 johnson 2 stroke cooling

In looking over this thread I have missed the easiest and common solution. Make sure your leg is well into the water. Like I'm talking 1/2 way up to the power head. Many times people just don't get enough water in the barrel. I agree to try it without the stat in place. If the grommet at the pump is a little closed off it will behave this way as well. Don't worry, your gaining on it. Rick.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Okay finally got back to it and tried in the barrel without the thermostat and still acting the same. Checked for water exiting at the shift rod but looked ok there so suspect the grommet at the outlet tube to be fitted alright. Tried in neutral and forward. Open to any other ideas. Thanks

 

[bktheking]

Re: 1999 9.9 johnson 2 stroke cooling

If you look at the water flow diagram here:

http://www.sschapterpsa.com/ramblings/water_circulation.htm

You will see that the telltale is the first place water gets to soooo, if it's hot coming out there is a blockage in the block or the exhaust plate.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Ok back home after a week of unbeleivable fishing at Kinbasket lake.
Removed the bottom and inspected everything again. Rigged up a hose adaptor to the outlet tube and all flows looked good from the pee hole and the block. Removed the stat and the same flows. Next I put the bottom in water and used a battery drill to turn the shaft but absolutely no flow from water pump, but this may be normal without flow restrictions to the block, I don't know. Increased drill speed did not change the result. But what I did notice after I removed the pump for inspection is that the impeller vanes had reversed but this may be normal also if you look at shaft direction and water pressure in the pump. So again I am in the hunt for further aid. Thanks

 

[AlTn]

Re: 1999 9.9 johnson 2 stroke cooling

you tube has a video, "Water Pump test on a 1978 Johnson 9.9 outobard",which may help you to determine if pump is working prior to reassembling to leg.Reversed vanes may be from your drill turning the driveshaft in a ccw direction.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Watched the video and did the same procedure again and the only evidence of water exiting the pump was acceleration above idle speed. Now yes I am relying on my instincts that the drill is resembling gas throttling, but even if I am off somewhat I still feel there should be flow with any shaft movement withih reason. There isn't the flow that the video demonstration shows. The vanes reversed again and shaft test was always clockwise.

 

[Rick.]

Re: 1999 9.9 johnson 2 stroke cooling

This must be driving you nuts. I guess my next suggestion would be to make certain your water inlet from the leg to the pump is absolutely clean and nothing in there to obstruct good water flow to the pump. Your idea of testing with a drill is sound as long as you can get 600 rpm out of your drill. Have a look and let us know. Rick.

 

[AlTn]

Re: 1999 9.9 johnson 2 stroke cooling

If you haven't, the manual calls for a bead of Adhesive M ( the substitute is listed somewhere here in the iboats forums) be applied to the base of the water pump impeller plate before it is installed. I'd also advise you check to insure that the cup hasn't slipped in the water pump housing which would restrict the flow of water from the pump. The vanes reversing makes me wonder if maybe this isn't the proper impellar for the 9.9? As the leading edges of the vanes sweep the cup, the resistance should be such that it's difficult to reverse their direction while turning the impeller by hand. Hope this helps.

 

[6point]

Re: 1999 9.9 johnson 2 stroke cooling

Yes the inlet is definitely free from both sides and the drill will do 600+ rpm. Is 600 the base shaft rpm at idle or does this have another significance? The pump base plate didn't have any indication of sealant on it when I removed it and I have owned this since it's birth. I will get some sealant when we get this figured out. If you look at the bottom side of the pump the vanes are cupped in the direction of the cup opening just as in the article mentioned in the sschapterpsa.com site but after a test they have reversed and cup away from the cup opening. The cup doesn't move in it's housing either. The impellar is the same one recommended by Johnson plus I put the old one back in also as it is in excellent shape. It's as if the outer edge of the vanes are grabbing the inner cup race and flipping backwards to sweep the water rather than cup it, maybe that's the way it works? Aitn you mention sweeping but I thought that after viewing the above mentioned site that the vanes were to stay cupped while under operation. Thanks for all your input. Yep Rick it is befuddling me.