posted 04-16-2008 10:08 AM ET (US)        

Has anybody found a product that can be used to improve the watertightness of the engine cowling or come up with any other solutions?.

Thanks,

posted 04-16-2008 10:53 PM ET (US)            

I've had my Opti in service since August of 2002 and have 2783 hours the motor, all in saltwater. The cowl design and seals have protected it in all kinds of weather and sea conditions. My OptiMax has stayed dry in heavy rain, snow, and copious amounts of salt spray.

Here's what the motor looks like after all these hours on the ocean.

http://bluewaterpirate.phanfare.com/slideshow. aspx?username=bluewaterpirate&album_id=347992§ion_id=474715

posted 04-17-2008 12:59 PM ET (US)            

I purchased a new Montauk 190; I'm awaiting delivery on it in July. I was concerened that it has a Mercury on the back as I'm not a big fan of these engines, however looking at yours after 2700 hrs makes me feel a lot better.

Thks for calming my fears for the moment.

posted 04-17-2008 01:26 PM ET (US)            

I've been very happy with its performance and gas consumption numbers. The motor has been a true work horse.

Mercury learned their lesson well from all the problems they faced when the Opti series was first released.

Good luck with your new Montauk and enjoy the memories it will give you!

posted 04-17-2008 03:45 PM ET (US)            

I had a compressor bearing issue in mid 07 (heard the dreaded chirp). Took it to my mechanic, who found that indeed I had a bad bearing in the compressor. He called Merc who asked him for a serial # of my compressor. Within 5 minutes Merc told them to replace the compressor under warranty, they're reason for authorizing this was the original compressor was from a lot that had had previous bearing issues. At that point my Opti was 1 month out of warranty and Merc knew that (I had the 5 year extended warranty) but they choose to cover it under warranty. To say the least, I was a happy camper, saved $850.00 replacement/labor costs. That's the only issue I've had.

posted 04-17-2008 10:02 PM ET (US)            

As far as latching sequence is concerned does it matter what side is closed first either the front first then back or vise versa? In the information that I have from Mercury it says to latch the rear first then the front. I have up until now been latching the front then the back. I can't see why this would affect the sealing of the engine. If somebody can explain I'd appreciate it.

Thanks,

posted 04-18-2008 09:39 AM ET (US)            

Andrew - did you look closely at the placement of the gasket strip on the bottom cowel halves. Just makes sure nothing has been pushed out of place. I like very much and have used the "glen e" procedure with great success over the years. If Glen is lurking, he can chime in and clarify but here is what I do:

About once every three months I remove the cowel and spray the block down with a 50/50 mixture of water and saltaway from a spray bottle. I put my garden hose nozzle on "mist" and mist/rinse the saltaway mixture off. I do this procedure in the morning and leave the boat out in the hot sun for the rest of the day so all water dries off. Leave the cowel off to facilitate drying. At the end of the day when its completely dry, I spray the powerhead down with Mercury "Corrosion Guard" spray. There are many other products which will work equally as well though. Even if you get a little salt on the engine, this procedure will ensure none of it starts to corrode any of the base metal. Use common sense when spraying around rubber products, especially around your timing belt.

posted 04-18-2008 10:41 PM ET (US)            

You maybe right that there are no poppet valves on the 90HP. I do not know one way or the other.

I do have a 225 Optimax that had a poppet valve fail. The salt deposits Andrew described reminded me of what I saw on my engine before discovering the problem with the poppet valve.

posted 04-18-2008 11:40 PM ET (US)            

What is a poplet valve?? What does it look like? Again boat is a 2008 170 Montauk with a 90 HP Mercury [FOURSTROKE].

posted 04-20-2008 12:33 AM ET (US)            

Also it is good to hear about the sealing of the cowling on four-year-old motors, but they can't be the FOURSTROKE Veradito, which just came out about a year ago.

Yes, in my own first hand experience the cowling on older Mercury motors was very difficult to remove due to a tendency for the fit of the gasket material to be very tight. Also the gasket material used to be a vinyl-like material. It seemed to have a tendency to stick to the cowling and the lower pan, making the separation difficult.

Vaseline, or more properly vaseline petroleum jelly, is a petroleum grease material. There are some reports that application of vaseline or any petroleum grease is harmful to rubber and is to be avoided. An alternative is to use a water-based lubricant like K-Y jelly. Of course, since you're trying to keep water out, a water-based grease may not be the best choice either. Another alternative is silicon. However, silicon can cause damage to some of the sensors used in modern engines, and you should be careful about spraying it near the engine. As a general precaution, I suggest you do not get silicon spray into the air intake path.

A poppet valve is a valve of a particular shape and generally operated against a spring, and in outboard motors they are common in the cooling system where they respond to changes in the PRESSURE (not the temperature) of the water flow. Typically the function of the poppet valve is to remain closed until the water pressure increases to a certain stage. This usually occurs with increasing engine speed, when the cooling demands increase. Therefore the poppet valve provides a way for the engine cooling system to increase the cooling with increasing engine speed.

posted 04-20-2008 07:27 PM ET (US)            

Thanks for you explaining the function of the poplet valve.

I have a hard time beleiving this is the cause of the water intrusion. Once again I only have salt creep around the rear latching mechanism on the engine side and salt crystrals on the the latch itself on the cowling. Occasionally there is salt on the the second from the top cylinder cover where the spark plug goes, but this is very superficial.

I have since reversed the latching sequence for the front and rear latch. Hopefully this modification in latching sequence will fix my problem. Will try it out next weekend and let everybody know what I find out.