3 cyl Merc 40

[HGipson]

Jon builds fast motors jetting is very important on how the motor will perform. their reeds are also worth spending the money on. If you are assembling it yourself clean it with soap and water real good before putting it back together. also if you removed the rods change the rod bolts.

I had Jon disassemble, port/bp work, honed cylinders new rings, replaced on piston that was scored a bit, and Hydrotec reeds/60 reed stops, intake work and put powerhead all back together for me. I didn't have time to do it and I haven't ever gutted one of these particular powerheads. The motor was an ELPTO 40 2004 model. I ordered all new tiller, gear shift, remote key and trim switches and everything else it needed the day I picked it up. Its in really good shape from what I have seen. After I sent off the powerhead I cut and welded the tuner up, gutted the cowling and drilled holes in back handle for more air, new water pump while I was at it and all the other little minor stuff y'all and a friend of mine on here have helped me out with ( which I really appreciate ). Got it all back together back to how it should be and just waiting on my powerhead to be here next day or so. I've got 60 carbs with .062 jets I put in em the other day and .060 jets to put in and try. Got .090 idle circuit air jet. Got a mercury thermostat kit (110 or 120 can't remember) on the way for this cold water. It's going on a 1648 War Eagle plain old duck boat to run the boat trails on the swamp with so it won't be at any races hopefully it lasts a long time or it'll prolly cause a divorce in the Gipson household!! Lol. I've had a lot of help from all of y'all and I appreciate it. If there's any other small tinkering I can do to get everything just right or I've got something wrong feel free to let me know I'm never to good to listen and take y'all's advice. Y'all are the kings of the Merc 40's!!!

[omcstratos]

post a first startup when you get it back together. Looking forward to see how it runs

[HGipson]

post a first startup when you get it back together. Looking forward to see how it runs

I'll try... All depending on if it starts on or not! Haha. Hopefully it all works out man I'm all on on this motor already my wife would make me suck start a 12 gauge if there's any major problems! Been hounding me ever since I sold that brand new motor to buy an older one to fix up! Lol

[fs5]

hi mate,i've got a stock 59ci 55 merc,i run my timin at 25* ,I think stock is 24*.the mercs cdi takes timing out once the motor hits 5000rpms ,I can't remember if it takes 2 or 4* of advance out of it.
you must be makin some good power to run .062 jets. my motor came with .058 from the factory ,now runnin .056 in it .
is 135lb comp standard for the 40 mercs? my motor was 120lb when it was new ,now it only pumps around 112/113..
what do you guys do to get more comp out of them.

[HGipson]

Man that's what my compression tool said it was a brand new one just got. Tested the com tool against air compressor pressure (120) and it read perfect so it shoulda been right. I thought they had around 140 from factory new but I might be wrong. My 25 Mercury I rebuilt last year had 140 on both cyl after we honed, new rings and broke it in. Still got around high 130's a year later. They say these motors don't do well with raising compression a lot. Some guys are using nitrous I don't know how long the motors last/run but of I had the money I'd have me some NoS too!! Yeah I think I'm gonna leave the timing alone for now. These motors will supposedly burn all the fuel the .062 will push through the 60 carbs with the way it's opened up now with intake, blue printing, and porting/polishing and tuner work. More air you can get through any motor the more fuel you can burn and more hp you can make if you got cooling under control and that's the beauty of outboards unlimited cooling!!

[Riverrat001]

hi mate,i've got a stock 59ci 55 merc,i run my timin at 25* ,I think stock is 24*.the mercs cdi takes timing out once the motor hits 5000rpms ,I can't remember if it takes 2 or 4* of advance out of it.
you must be makin some good power to run .062 jets. my motor came with .058 from the factory ,now runnin .056 in it .
is 135lb comp standard for the 40 mercs? my motor was 120lb when it was new ,now it only pumps around 112/113..
what do you guys do to get more comp out of them.

I'm running .070 in mine. It's a little fat but it won't burn up that way

[MWhite]

I had Jon disassemble, port/bp work, honed cylinders new rings, replaced on piston that was scored a bit, and Hydrotec reeds/60 reed stops, intake work and put powerhead all back together for me. I didn't have time to do it and I haven't ever gutted one of these particular powerheads. The motor was an ELPTO 40 2004 model. I ordered all new tiller, gear shift, remote key and trim switches and everything else it needed the day I picked it up. Its in really good shape from what I have seen. After I sent off the powerhead I cut and welded the tuner up, gutted the cowling and drilled holes in back handle for more air, new water pump while I was at it and all the other little minor stuff y'all and a friend of mine on here have helped me out with ( which I really appreciate ). Got it all back together back to how it should be and just waiting on my powerhead to be here next day or so. I've got 60 carbs with .062 jets I put in em the other day and .060 jets to put in and try. Got .090 idle circuit air jet. Got a mercury thermostat kit (110 or 120 can't remember) on the way for this cold water. It's going on a 1648 War Eagle plain old duck boat to run the boat trails on the swamp with so it won't be at any races hopefully it lasts a long time or it'll prolly cause a divorce in the Gipson household!! Lol. I've had a lot of help from all of y'all and I appreciate it. If there's any other small tinkering I can do to get everything just right or I've got something wrong feel free to let me know I'm never to good to listen and take y'all's advice. Y'all are the kings of the Merc 40's!!!

Ya'll get them 40s back togetther and running good and make a trip down here to south louisiana to sabine river and we will line them up.

[MWhite]

I'm running .070 in mine. It's a little fat but it won't burn up that way

yea but yours is hogged out dave,

[HGipson]

Man I go her back together today and running ! Fired right up after I threw the new neutral start switch in the trash that came with the tiller kit. Don't know why I wasted my time puttin it on there knew I was gonna disable it anyway. Sounds awesome I haven't been around but one of these motors before I decided to get one and build it up. Couldn't figure out how to post a video off my phone though. Gonna mount it on the boat and tomorrow afternoon and if I get everything rigged up gonna go run er 25:1 break in. May stretch her out a bit this wkd

[HGipson]

Ya'll get them 40s back togetther and running good and make a trip down here to south louisiana to sabine river and we will line them up.

Mike that' be a waste of time for both of us! Haha my old duck boat won't keep up with much even with this motor on it! But I may eventually find me a jack plate and put it on my old 14 ft Monark flat bottom weighs about 175 lbs that would probably be a death trap! Lol