Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Gas guzzling Mercury 225 EFI
Posted by robaguero on 10/14/07 - 5:51 PM
#1
Guys...i need help!!
Went out yesterday and burned about 60 gallons of gas in 4 hours!! And this was not at WOT (18 knots on average).....made the haul to one of my favorite fishing spots and could only manage four passes at 7 knots when i decided to turn back because of low fuel.
To make a long story short, i made to the marina but it was a very short call. I guess there is probably one or half a gallon of fuel left in the tank (left with aprox. 62 gallons) Something is not right and the simptoms are:
1) I am only getting 28 knots at WOT (i have read or heard that an Outrage 22 with a 225 gets at least up to 37-38 knots.
2) There a very noticeable lag on the engine to spool up and get to WOT when you pull the throttle forward (it takes way longer that what i have experienced on my previous boat and others i had driven).
3) Brand new NGK spark plugs (BR9HS-10)
4) Brand new Racor water separating flter and Merc internal fuel filter
Engine is very reliable and does not cough but i think there is something about the timing that is not right. Any other ideas besides the timing??
Posted by Joe Kriz on 10/14/07 - 7:42 PM
#2
rob,
That does sound extremely excessive. 15 gallons an hour... wow...
Was there a lot of smoke?
Almost sounds like the choke is on (if there is one) but you would see the smoke.
At any rate, it sounds like you are running way too rich....
Maybe some of the Merc people can give you more details.
Posted by Derwd24 on 10/14/07 - 8:51 PM
#3
I'd suggest pulling the plugs and checking them for carbon fouling, which would indicate the rich condition Joe mentioned. While the plugs are out, it's worth doing a compression or leakdown test to make sure cylinder integrity is OK.
Posted by Jeff on 10/15/07 - 7:16 AM
#4
If all of the above mentioned areas check out you will need to have a serious look into you electrical system. You could cylinder that is not firing. With a V6 if the one of the middle cylinders are not firing you may never notice a vibration, shudder, or shake that would indicate a misfiring.
Here is another thing, you might also have a blown head gasket. If the motor will not make full power, plane the boat boat as fast as it normally does, and runs sluggish this could be an indication. You will know if this is the problem by pulling the plugs. If you remove the plugs and find one that is prefectly clean while the other show normal carbon build up you have a problem. The plug will be clean because it is getting steam cleaned from the raw water that is getting pumped into the cylinder.
I know this situation all to well. Fortunately I was able to immediately know what was going on and get back to port thus saving the motor from complete failure. Head gaskets are cheap and easy to do. I would recommend replacing them to anyone with a motor they do not know the history on. I learned this the hard way.
Edited by Jeff on 10/15/07 - 7:32 AM
Posted by plotman on 10/15/07 - 8:19 AM
#5
If you have an outrage 22, you should have a 77 gallon tank, not 62, unless your tank isn't original.
At a fuel burn of 14 gallons per hour, I am running 35-36mph (31 knots) in my outrage 22 with standard 2-stroke engines.
I don't have fuel flow data for my old boat, but I could get 43-44mph out of my first 22 with an old 200 hp merc 2 stroke on it.
Something is clearly wrong.
Posted by robaguero on 10/15/07 - 8:49 AM
#6
Thanks guys...i will pull the plugs out and check them.
Jeff, thanks for the advise on the head gasket...will do it before going out again. I think it is worth it.
And yes, my tank has 77 gallons of capacity but it was not full when i went out.
I will have a very good outboard technician come and take a look at the motor.
Thanks everybody for the quick response.....
Posted by Tom W Clark on 10/15/07 - 11:31 AM
#7
It is not the fuel consumption so much as the speed that is of concern to me. An Outrage 22 with a 225 should be able to do 45 MPH or better.
We would expect a 225 to consume about 22-23 gallons per hour at WOT (general rule: 1 gallon per 10 horsepower). My Mercury 150s consume about 7.5 GPH at cruise speed and about 16 GPH at WOT. I would expect a 225 to consume about 11-12 GPH at cruise speed. 15 GPH is high, but not *that* high.
Given that you are topping out at 32 MPH I have to think something more sinister than a rich mixture or a missing cylinder is the culprit here. My own guess is that it is missing two or three cylinders for some reason. To achieve speed, more throttle has to be given so the remaining cylinders provide the power yet the non-firing cylinders are still getting their fuel, thus the high consumption rate.
I suspect a mechanic will find that some of the CDIs are shot or the switch box needs replacement. I'm with Jeff, I suspect something electrical in nature.
Edited by Tom W Clark on 10/15/07 - 11:32 AM
Posted by robaguero on 10/20/07 - 10:27 AM
#8
I could not sleep last night after spending tha whole morning with the outboard technician and finding that I WILL HAVE TO REPOWER!!
After all, when i got into the project i figured out that eventually i was going to replace the motor.
We basically found the following:
1) A couple of power reeds with some bumps on them
2) One cylinder liner with scratches from an almost loose piston rod
3) A small crack on the motor block.
The engine had been running with just 4 cyilinders and that is why i wasnt getting more than 28 knots and sipping all that gas in such a short time.
So, now im in the hunt for a 200-225 Optimax or a 200 Saltwater Series or Enduro Yamaha. Im going to take my time and see whats available but at least now i know what my problem is.
Hate to say goodbye to the water for some time, though.
Posted by Derwd24 on 10/20/07 - 11:14 AM
#9
Rob, I feel your pain, went through the same thing with my engine in August after just 3 weeks on the water. Now I have a pretty lawn ornament that reminds me daily of what I'm missing! I'm looking on the bright side though and can't wait to get a more fuel efficient engine for next season as like yours, mine used WAY too much gas. The fuel savings alone will go a long way towards the cost of the new engine! Good luck,
Dave