twin 5.0 run at different temps

[crazy charlie]

Hi guys,I need a few ideas.I have twin 5.0lx merc stern drives(230 hp).I have had this boat for 1 full season and before I ever put it in the water I did a water pump service in the o/ds,water circulator pumps,manifolds and risers and thermostats.My port temp is right where I want it to be and stays near there all the time145-150 The starboard idles at 150-155 and fluctuates as cruising.It goes up a little to maybe 170-175 and then comes right back down to 155.I have also checked all hoses.Any ideas are welcome.I am changing the gauge and sender next.Charlie

 

[flashback]

Re: twin 5.0 run at different temps

If all else is new as you say, then swap the thermostats and see if the problem follows.

 

[delta breeze]

Re: twin 5.0 run at different temps

I agree with Flasback!

 

[crazy charlie]

Re: twin 5.0 run at different temps

unfortunately the thermostats i did not do last year,i just did them the other day and same ol same ol.I was going to try swapping the sending units.Charlie

 

[crazy charlie]

Re: twin 5.0 run at different temps

..

 

[FreeBeeTony]

Re: twin 5.0 run at different temps

How about the timing? Maybe the one running a little hotter is more advanced than it should be?

 

[crazy charlie]

Re: twin 5.0 run at different temps

Thanks Tony but the timing is correct on both.I am thinking of doing a descaling to the warmer motor,maybe its just dirty on the inside.Charlie

 

[Boatin Bob]

Re: twin 5.0 run at different temps

Charlie...before replacing senders and gauges, why not pull the wires off the 2 senders and use jumpers across to see if the problem moves or stays and then take it from there. Should be able to eliminate it down to a sender or gauge or engine problem.

 

[crazy charlie]

Re: twin 5.0 run at different temps

Good idea Bob!!!!!Process of elimination.Charlie