Confused about cooling issue - '83 50 hp Evinrude

[USS Neversail]

OK, here is the issue . . . overheating, getting warning buzzer when run over 5 min or so. Guage says 5-7 psi, then drops off with acceleration to zero or 1 psi. Obviously, it's supposed to read much higher than that. Same with tale-tell stream. Starts off strong and then weakens. At home, I put it on hose and muffs and the tale-tell was strong, with no overheating. Replaced waterpump and impeller approx. one year ago. Replaced thermostat, no fix.<br /><br />Questions:<br /><br />1.) The water tube goes into waterpump housing. There is a rubber gasket type thing that acts as a sleeve/seal for the tube. When changed, was very loose fit. Would slide/fall off if I held it up. Is this supposed to be this loose?<br /><br />2.) What is the best way to check if there is a clog in my cooling system? Without tearing it apart? <br /><br />Planning on replacing the entire waterpump, impeller, o-ring set up again this year anyway, so will be doing that. Any suggestions if this doesn't cure the problem? Not real confident that it will, because I did that last year with poor results. <br />Also having electrical problems . . .don't know if this is helpful, but the warning buzzer wire was shorting to the coil wires . . . will need to replace soon, but electrical taped for now. LOTS of electrical tape. <br />Thanks, in advance.<br /><br />Jason

 

[Xcusme]

Re: Confused about cooling issue - '83 50 hp Evinrude

The water tube to pump housing rubber grommet should have a snug fit on the water tube, this seals the water pressure going to the powerhead. If it's leaking (sounds like your problem) the increased pressure of the water pump at higher RPM's isn't allowing cooling water to reach the powerhead. Drop the lower unit and replace the seal. Don't run the motor without proper cooling.

 

[USS Neversail]

Re: Confused about cooling issue - '83 50 hp Evinrude

Is there a way I can tell if it is leaking? Like water in the gear oil? <br />Or a flag popping up? Kidding. <br /><br />Thanks. Will do when I replace everything. I got a kit last time . . .if the grommet is loose again, can I seal it with sealer or something like that? <br /><br />Thanks, again. <br /><br />Jason

 

[USS Neversail]

Re: Confused about cooling issue - '83 50 hp Evinrude

Ok, thanks for the replies. I am gonna go get one now . . . try to replace it tonight and let ya'll know how it goes. <br /><br />Thanks, again!

 

[BF]

Re: Confused about cooling issue - '83 50 hp Evinrude

a couple of merc guys just went through this (loosing water flow at higher rpms)...long threads on the Merc forum. If I recall correctly (you'd better check yourself), one case was due to a leaky pump base seal, presumably sucking exhaust into the water pump base at high rpm's, the other was cured by replacing the impeller (even though it appeared OK).<br /><br />That's the problem with having these forums split into "brands" you can miss some threads that would be helpful. I don't think there's anything OMC specific about your problem, but some folks with Force or Merc's may never see your question!<br /><br />Brent

 

[clanton]

Re: Confused about cooling issue - '83 50 hp Evinrude

There was problem on some 50hp engines with the grommet under the power head restriction water flow. Check the part number changes and look at new grommet, seems like the new style was a 2 part hard plastic, instead of rubber grommet.

 

[USS Neversail]

Re: Confused about cooling issue - '83 50 hp Evinrude

ok, thanks for the replies! I will certaintly check the merc site and will look again at the grommet that may be two parts. I had to order in an impellar and new grommet, so won't be able to do anything till this weekend, as it won't be here till Friday. As soon as I get the work done, I post an update. <br /><br />Once again, thanks for the help. I really appreciate it.<br /><br />Jason

 

[catfish1]

Re: Confused about cooling issue - '83 50 hp Evinrude

had about the same thing happen with the 90hp merc last weekend. found out the stainless steel water pump housing spun out, it would pump a little at low rpm, but less at higher rpm.