Water and Exhaust:

[bjperry]

I put a rebuilt power head on my '78 V-6 150. I used the gasket provided by the seller of the PH when I did this. The gasket looked a little different from the original, but looked like it had all the right ports cut. Anyway I finally got the thing started today and am taking precautions to make sure I don't burn it up first thing. I'm worried by a couple of things I've noticed. First is that I have no water coming out of my telltale outlet at idle. I pulled both thermostats to make sure I wasn't having any blockages there with the same result. If I rev it up a little I get a few bubbles of water but still not a stream. While no water seems to be coming out I do seem to be getting air coming out of the telltale; kind of puffing. The next thing I notice is that while I have exhaust exiting the ports halfway down the lower unit I only have water exiting around the prop. Is this normal or should I also have water coming out of the ports halfway down? What might account for the lack of water out of the telltale? Should I have air coming out of there? Should I go ahead and just order the gasket called for and pull the PH off and replace it? The seller said he thought it was a hi performance gasket but I don't really know what he meant.

Any help is much appreciated.

 

[CharlieB]

Re: Water and Exhaust:

If the gasket did not fit the adaptor perfectly then change it with the correct gasket, it is NOT worth toasting your new power head.

New power head deserves it least a water pump kit, T-stats and fuel pump kit, all are cheap insurance that your motor lives.

Double check water transfer tube upper seal.

 

[bjperry]

Re: Water and Exhaust:

CharlieB,

The new gasket fit, it just had slightly different ports than the one I took off (I actually think it had more ports than less but could be mistaken). I rebuilt the water pump last year before deciding I needed a new power head, t-stats were replaced at the same time. I have a fuel pump rebuild kit which I'll probably take care of this coming week. Also figured on pulling the carbs and cleaning them up to make sure I'm not running lean on any cylinders.

From what I've read it appears that unless the poppet is opening I shouldn't be seeing any water coming from the exhaust ports directly below the cowl. Since I'm only idling I'm probably not building up enough water pressure to open the poppet and therefore not seeing any water exiting those ports. To check this I think I'll pull the poppet and run it without the diaphragm just to confirm that water will exit those ports when pressure builds. I put a new poppet assembly in this power head yesterday but noticed that I'm getting a little water coming out of the vent hold in the center of the poppet valve. Others indicate this means a bad diaphragm, but since mine is new I don't think that's the case. Perhaps it's just not seating properly. I'll have a look at that when I remove it.

Still I don't understand why my tell tale is either weak or non-existent. My hose routing goes from the port side t-stat over to the starboard side t-stat. The starboard side t-stat also goes to the poppet valve. My tell-tale comes directly out of the block and doesn't seem to be plumbed into the t-stat hoses at all. From other posts I've read I see that some people plumb the relief valve directly into the water jacket via the 1/2 inch plug in the top of the motor right behind the flywheel. I don't think that's how mine was intended to be routed. But if that's what I have to do to get water out of my tell-tale perhaps I'll have to do that.

Thanks for the help and any other ideas will be great.