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ContinuousWave: Whaler Performance
Merc 115 4 stroke on rescue boat
|Author||Topic: Merc 115 4 stroke on rescue boat|
posted 08-09-2002 08:28 AM ET (US)
I have now had the opportunity to put about 15 hours on a pair of Merc 115 EXLPTEFI4SSW 25" that are on our water rescue boat, and I have a few opinions.
First, about the boat...
It is a Outrage 22' cuddy with Whaler Drive and super console. This boat has been set up as a combination fire supression and water rescue vehicle. Through the topside of the cuddy is a high pressure attack gun. This is connected by means of flex hose to a 1000 gpm pump that is mounted under the leaning post.
The boat has a T-Top, full electronics (radar, chartplotter, 3 radios, cell phone, depth sounder), full lights and sirens, complete rescue gear, foam system, etc.
This past winter, Mercury donated a pair of 115 EXLPTEFI4SSW 25" to replace the onld 110 Johnsons.
The new engines are wonderful. While not available in a counter rotating model, any list is easily trimmed out. Starting these motors is a dream. They are so quiet that there have been times that I have had to check the tachs at idle to make sure they were running.
Hole shot is good, but not as immediate as with 2 strokes.
Top end with all the equipment and out team of 3 is about 33 mph.
I am still not sure if these engines burn gas at all. Last night we spent about 4 hours doing a lot of high speed searching (for lost PWC riders AGAIN). Total fuel consumption was less than 20 gallons.
These engines do have one MAJOR drawback however. Shifting from fwd to rev is a complete bear. Merc has said that it is ann ignition problem and they are aware of it. As explained to me, when shifting like this, the ignition shuts the motor off for less than .5 second to allow the gears to mesh into reverse. Well this ignition shut down can not occour until the engines have set below a certain RPM. Replacing the aluminum props with stainless ones have helped a bit, as the added weight of the props help slow the engine quicker; but it is still very noticeable (BTW the stainless props were another donation by Merc).
All in all, I am very impressed with these motors. They have proven reliable, economical, and quiet. Not to mention the reduction in emmissions.
posted 08-09-2002 10:55 AM ET (US)
Thanks for the report on the Merc engines.
That shifting cut-out for reverse sounds like the same technique that was used on many I/O drives. The engine is momentarily killed to ease the shift into reverse.
Have you noticed any tendency for stalling when you shift into REV?
posted 08-09-2002 11:09 AM ET (US)
"high presure attack gun" that sounds like fun, where can I get one?
posted 08-09-2002 12:18 PM ET (US)
Yes, it is essentially the same system as the I/O's on my Bertram.
I have yet to experience any stalling while shifting. That ironically is the problem. In order to compensate for that issue, the "window of oportunity" for the shift has been reduced to a very small time frame. The net result is the difficulty shifting. It was a choice of the lesser of two evils I think.
A high pressure attack gun is a very cool thing indeed. Imagine pushing 1000 gpm through a fixed mount nozzle that operates on a gimbal mount. It can thorw a constant stream over 200 feet. Heh, heh, can you say riot control? :)
posted 08-09-2002 04:41 PM ET (US)
How about a picture?
posted 08-09-2002 07:25 PM ET (US)
Pictures will be taken tomorrow, and sent to Jim for posting.
posted 08-09-2002 08:40 PM ET (US)
Sounds like "THE RIG" to me for rescue operations. As far as the hesitation, I have a 90 4-stroke which originally came without the shift interrupt, as Merc calls it, and you would have to wait a little too long for the idle to slow enough to avoid the "clunk" when shifting into reverse. Merc then added the shift interrupt switch and all of its 4 strokes and even covered the modifications on the ones without. Like you said, it"s a choice. All in all, I"m very please with the performance of the Merc. Just my $.02.
posted 08-10-2002 12:25 AM ET (US)
Lost PWC riders again? Riot control?
I sense a real temptation.....
posted 08-10-2002 07:24 AM ET (US)
I'd like to see about trading pictures and patches if you are interested. We use a Edgewater 185CC and a 200CC as fire/ rescue/ dive boats. For fire suppresion we have a portable 750gpm pump which can be moved from boat to boat.
posted 08-10-2002 08:12 AM ET (US)
I have sent some pictures to Jim. Hopefully they will show up here soon.
I would like to swap pictures etc. Send me an email.
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