over heat alarm

[buzo]

1989 110hp evinrude v4 crossflow....i recently installed 2 new thermostats into this motor. i wasnt having overheats problems until i did this.i was careful to assemble correctly <br /> <br /> the supplier of the parts only had 1 grommet and relief valve . i had to leave 1 of the old ones in for now ...i did not replace the springs.i thought they looked ok. both the old relief valves had been melted sightly.<br /><br />there is water comming out the pee hole but i will be replacing the water pump.<br /><br /> i ran motor for a bit and the alarm went off for the over heat... the constant beep sound... i then let it rest for a bit and tested the horn by disconnecting the thermo swiitches and grounding the wire to the block (with the key "on")and the alarm went off.....i then ran it WITHOUT hooking up the 2 leads that go the the sensors and felt the heads and they were hot to touch... when the overheat alarm went off again....even with the wires disconnected? is there another sensor ? <br /><br />also i had moved adjusted the wheel nut on the timimg advance shifter when i was out in the lake to adjust the idle. i didnt move it very much .i dont know if this has changed the detonation to much to cause the heat problem.... thanks

 

[OBJ]

Re: over heat alarm

buzo....if you can lay your fingers on the flat area on top of the block just forward of the heads for several seconds before removing them, and the temp sensors leads were diconnected, then you got another problem. Is the tone a constant one or intermittent. If it's intermittent, you have a problem with the VRO. Goes like this.<br /><br />An urgent 1/2 sec tone every 1/2 sec...restricted or no oil flow to VRO.<br /><br />A 1/2 second tone every 20 seconds or so...low oil reservoir level.<br /><br />Steady tone...overheat.<br /><br />If your getting the constant tone with the sensor leads disconnected, the warning horn may be going bad.<br /><br />Here's a test....find the lead from the Vro pump and disconnect it at the amphenol connector (that's a fancy name for rubber plug). Look for the lead coming from the oil reservoir. It will look like a black lamp cord. Disconnect it at the bullet plug. Leave the temp sensors disconnected. Start the engine and see if the alarm re-occurs. If it does, chances are you got a bad horn module.<br /><br />Keep us posted.....thanks.

 

[Joe Reeves]

Re: over heat alarm

Buzo.... You say that you didn't have a previous overheat problem. However, if those nylon bypass valve tips were even slightly melted, you did have a previous overheat problem.<br /><br />You've said nothing about dropping the lower unit to inspect the water pump. That would be the logical place to start.<br /><br />The longest portion of the thermostat should face the thermostat housing, not the engine. It's possible to insert them backwards... difficult but possible. No offense intended here, just a reminder.

 

[buzo]

Re: over heat alarm

OBJ, it is a constant alarm (steady tone). all vro has been disconnected and tested to not alarm or function.<br /><br />joe, i will drop the lower unit today and inspect and ive installed the thermos the way you refer to. =) no offence taken at all..=)<br /><br />i just bought the boat for a good deal ... it had been sitting out of the water on the ocean since nov and the waves and wind had blown up the exhaust and had frozen the the cylinders. i have freed them up and have replaced head gaskets adn power pack and when i get more money will replace the water pump. i have not had time to drop the lower unit but will try to do it today...i think the previous owner may have over heated it. it had some singed wires that wrap around the exhaust housing. i havent even ran it for mre than an hour at idle and once on the lake for bout 10 minutes...and there was no alarm. i will post further info today....= )

 

[buzo]

Re: over heat alarm

ok i got the carbs off and cleaned them , the primer inlets on each carb were clogged hence the malfuntion of the primer valve.<br />i took the bottom end off and exposed the water pump (impeller)...it didnt look too bad with some little cracks in it. the crome plate that sits under it has a smooth 1/4 inch wide groove warn into the plate. that impeller was welded to the shaft. i cut the rubber impeller off with a rasor and carefully used a hand grinder to grind off the brass grommet that held the impeller.<br /><br />i also noticed that the gear oil that was drained form the gear box looked a lil biege...not white , but a dark beige. maybe some water gettting in.?? it had lil if no metal shavings it it.<br /> <br />i will replace the impeller and report back with results.<br /><br />also it was way easier to remove the gear pin from underneath the carbs AFTER i removed the carbs. = )

 

[buzo]

Re: over heat alarm

ok i finally replacedth the whole pump and it is cooling fine....new problem... probly carb related...<br />i got good spark to all cylinders...1 and 2 are not firing replaced plugs and still not firing....the carbs have been cleaned but not rebuilt...does the upper carb feed the 1 and 2 cylinders while the lower carb feeds the 3 and 4 ? im thinking that it may be the floats? maybe getting to much fuel...<br /><br />i have new gas 50:1 (vro disconnected)it seems to smoke quit a bit, i recently decarbed motor with "evinrude engine tuner" , and followed the running procedures.<br />im thinking that this is a carb problem....any ideas ? thanks <br /><br />also, there seems to be a little bit of play (not much) when i wiggle( not rotating) the flywheel back and forth , could this be a seal or maybe the pin that has sheared ?