CONTINUOUSWAVE

I just returned from using the boat in what had been the typical failure situation: I motored across the lake to the restaurant, had wine and snacks, then I hoped the Mercury 90-HP engine would start. The engine did start, just fine. My passengers were happy. Also, I think the engine is now running ...

Mark and Jim- Thank you for the tip on the fuel pump. After messing with a poor quality aftermarket pump, I bought the Mercury rebuild kit and in 10 minutes had a rebuilt pump. The diaphragm membranes were stiff, but seemingly functional. The check valves were ok. I did find 10-12 little hard pieces...

Mark - Many thanks. I was hoping find someone who had these same symptoms. I ordered a replacement pump and it arrives in a few days. Hope this does a new fuel pump is the remedy to the erratic starting.

Thanks for your ideas

Thanks for replying. I'm not aware of unusual smoke, but I haven't directly paid attention. This motor often smokes when started. Possible oil injection is too high? I remember having to lower the injection rate after some number of running hours. I could try to dial it back a bit. Is it possible to...

[A c.2003 Mercury 90-HP two-stoke-power-cycle engine exhibits unusual starting problems. The problems occurs in the following situation: ⋅ the engine is started and run for about three minutes propelling the boat; ⋅ the engine is shut off for about one hour; ⋅ the engin...

Q1: what [electrically operated] water pressure gauge [with a remote sender] is now used by Boston Whaler [on their 170 MONTAUK boats]? I plan to replace the present engine [2002 Mercury 90-HP two-stroke-power-engine] water pressure gauge with an [electrically-operated] gauge [that connects to a rem...

Thank you all for your comments. I ran the engine in a lake for all tests. I tested each cylinder with an infrared temp gun. After 25 [minutes] of cruising, the temperature I was measuring never exceeded 125-degrees-F. [NEW TOPIC has been moved to its own thread for discussion in the SMALL BOAT ELEC...

[The engine that is under discussion in this thread is a ] 2002 Mercury 90-HP two-stroke=power-cycle model. I have been able to connect a bench pressure gauge directly to the tee fitting where the dash mounted gauge is fed. The behavior is exactly the same - Idle and low RPM I get 5-10 PSI, on accel...

My 2002 Mercury 90 two-stroke-power-cycle outboard engine with less than 200 hours has failed to start twice in the last week. To me this indicates the cause of the no start is due to the gasoline fuel, or due to the carburetors, or due to the spark ignition. Q1: where can I start the diagnosis of t...

Thank you all - I will confirm operation of the gauge. I suppose there are other components of the water pump system (such as the tubing and O-rings) that could be failing, but the impeller installation was correct, and, as I stated, the impeller I pulled out looked to be in very good shape. That su...

@jimh - thank you for your comments. It is in fact a Mercury 90HP 2-stroke as delivered on the Montauk 170 in 2002. It has had very little use, and has under 200 hours on the clock. I think I may temporarily install my shop pressure gauge directly to confirm that the hysteresis you suggest is not oc...

Thank you all for comments. I'm not inclined to blame the impeller. When I pulled off the old impeller, it was in very good shape. The blades snug up against the housing. I installed a new Mercury OEM part and confirmed correct rotation and operation of the pump components. The symptoms now are iden...

Q1: is a reduction in cooling water pressure with increase in engine speed normal for 90-HP two-stroke-power-cycle outboard engine used on a 2002 170 MONTAUK? [Moderator’s note: the author needs to explicitly mention the manufacturer and model and year of the engine.In a follow-up post seven days la...