'91 175HP Mercury Outboard Overheating

[thono]

Just replaced impeller and both thermostats before putting boat back in water. Both thermostats were pretty much corroded away. Well after starting engine, there is no water pissing out at idle until engine heats up a little then steam starts to come out. After needle hits 1/4 mark on temp guage then water will spurt out but not a steady stream. Not until I actually start moving above an idle speed does the engine start to stream water out. Any suggestions would be very much appreciated. Thanks in advance. P.S.- I live on the south shore of L.I. and run the boat in saltwater.

 

[corm]

Re: '91 175HP Mercury Outboard Overheating

Hi,<br />Is the poppet relief valve in good condition?<br /><br />corm

 

[thono]

Re: '91 175HP Mercury Outboard Overheating

Thanks for the response corm and sorry for being the novice that I am but maybe it's time I bought the manual for the engine. But in the meantime what/where exactly is the poppet relief valve?

 

[ODDD1]

Re: '91 175HP Mercury Outboard Overheating

thono, it sounds normal to me...these motor didnt have a good telltale until motor was warmed up and rpms were over 2500.....

 

[thono]

Re: '91 175HP Mercury Outboard Overheating

Thanks ODD1, but I forgot to add that when idling down my canal, about 100 yards, by the time I got to the end the guauge was almost at 3/4 and as soon as I accelerated it came down to about 1/4.

 

[ODDD1]

Re: '91 175HP Mercury Outboard Overheating

Yes, when idling will go over halfway on guage....over 2000 rpm an comes back down.

 

[corm]

Re: '91 175HP Mercury Outboard Overheating

The poppet valve is located at the base of the motor on the starboard side. it is held in with 4 bolts. If it is not sealing the pump won't build enough pressure at low speeds.<br /><br />...have fun...corm

 

[dutt10]

Re: '91 175HP Mercury Outboard Overheating

sorry wrong topic

 

[Reel Appeal]

Re: '91 175HP Mercury Outboard Overheating

thono,<br /> Other than the poppet valve.....<br />1.Did you install the impeller with the vanes bent the right direction?<br />2.Did you re-install the impeller key(locks the impeller to the driveshaft)?<br />3.Is the water tube connected at both ends?<br />4.Did you remove the flush boot from the lower unit?(my brother did this once )

 

[chumbucket]

Re: '91 175HP Mercury Outboard Overheating

ODDD1 You been missing in action??? Did you get lost around beer bucket???? Have a good one!