Mercury Updates 40 to 60-HP Four Stroke Motors

  ContinuousWave
  Whaler
  Moderated Discussion Areas
  ContinuousWave: The Whaler GAM or General Area
  Mercury Updates 40 to 60-HP Four Stroke Motors

search | FAQ | profile | register | author help

Author Topic:   Mercury Updates 40 to 60-HP Four Stroke Motors

jimh posted 10-26-2007 09:27 AM ET (US)
Mercury has introduced new designs in their four-stroke motors of 40, 50, and 60-HP. Because Mercury has dropped any designation of model years, I am unclear how to describe these motors. The nomenclature for them is unchanged. They are called the 40-HP EFI, 50-HP EFI, and 60-HP EFI four-stroke models. It is unclear when the precise manufacturing epoch began for these new motors. The changes include a new cowling style, which should make visual recognition of the new models easier. The new cowling style is said to reflect the Verado motor cowling. I believe this is a reference to the curved line of the motor which arches up from the gear case to the top of the cowling in a smooth curve.
Among the changes in the new models, the most significant is a new gear case shifting mechanism. The new gear case is said to have "PRECISION ENGINEERED SHIFT." I believe that this refers to a change in the gear shift actuator to a desmodromic actuator from a cam follower and return spring actuator.
Desmodromic is a mechanical engineering term which refers to a valve or control device which is operated by different mechanisms to move in different directions. A good example of a non-desmodromic valve is the typical poppet valve in a four-stroke engine cylinder intake and exhaust. The valve is opened by a cam follower and closed by the spring. A desmodromic valve has direct positive actuators for each direction of movement. Previous outboard gear case shift mechanisms tended to use a cam follower and spring return design for the shift mechanism. Apparently in the new Mercury gear case used on these 40 to 60-HP motors the shift mechanism is now desmodromic. A simpler term might be "push-pull." There is also mention that the shift mechanism has been given greater mechanical advantage in order to provide a more positive engagement. The gear cases of Mercury outboards were somewhat famous for a tendency to have a CLUNK when shifting, so it is anticipated that the improvement to the gear case shift mechanism will reduce that tendency.
The cowling styling has changed, and the cowling latches have been redesigned and improved. The new latching mechanism is described as having the ability to force the cowling upward slightly when the latch is released. This loosens the cowling and makes it easier to grasp it for removal. In the past Mercury cowlings were somewhat famous for being difficult to remove due to the tenacity of the vinyl seal, which often stuck the cowling and the midsection together quite firmly. The lower lip of the new cowling design is now curved as opposed to being a straight edge. The curved cowling locates itself on the mid-section of the motor and helps align the two components. This style was first seen about five years ago in the Bombardier E-TEC motors.
Another area of improvement is in the throttle linkage. The throttle control is now said to offer finer resolution of engine speed, which will be particularly helpful at low speeds used in fishing by trolling lures.
The precise changes in the engine graphics are not apparent. It would be good to get more detail about the graphics inasmuch as the visual appearance of this motor will be key to identifying it as a new and improved model. If anyone has information about the exact date when the new motors replaced the obsolete models, or a serial number range when the new motor production began, it would he very useful to have this information available to potential buyers. In this way a buyer could more positively determine what motor he was buying, new model or leftover old model.
The 40 to 60-HP Mercury four-stroke motors are of moderate weight (247-lbs or 112-kg) and find application in classic Boston Whaler boats like the 13-foot and 15-foot hulls. These motors have the Mercury electronic fuel injection and advanced Mercury ECM 555 digital inductive ignition. These excellent features have already set these motors apart from competitor's engines in this horsepower range. These further refinements should make these motors more attractive.
sosmerc posted 10-26-2007 11:52 PM ET (US)
Hard shifting on these models (and all other models that have basically the same gearcase such as 75/90/115 Optimax and F115 EFI) has been a known problem for some time. Merc is finally addressing the issue and I have been trying to find out specifically what they have changed. I just got off the phone yesterday with one of my contacts that has "contacts" at Merc and he was trying to find out for me some specifics. He spoke with two different people at Merc and all they would say was that a cam change had been made.
My hope is that whatever changes they made, can be made to previous units as an "upgrade". I have several customers with Bigfoot lower units that can barely be shifted from forward to neutral with the engine running.
Been waiting some time for a fix.
L H G posted 10-27-2007 12:14 AM ET (US)
Here's Mercury's performance report to go with Jim's article.
http://www.mercurymarine.com/look_deeper/head_to_head.php?ID=52& Filter=11
jimh posted 10-27-2007 01:07 AM ET (US)
I found some previous literature from Mercury which mentions that the gear case on the 75, 90, and 115-HP motors was using a desmodromic shift actuator in c.2005 models.
sosmerc posted 10-27-2007 11:32 AM ET (US)
Merc changed to a desmodronic shift mechanism on their V-6 gearcases (2.0 and 2.4 litre) in the very early 80's. They called it "EZ shift".
They have not used this design on anything else up to this point. All the L3 and L4 gearcases have a pin that rides against a cam. The cam rotates and pushes the pin. The "profile" of the cam has alot to do with the effort required to shift. Also, the design and number of dogs on the clutch and gears will greatly affect the shifting effort...especially when the engine is running developing torque.
macfam posted 10-27-2007 02:46 PM ET (US)
jimh,
Do you think that the weight of the 40 EFI 4-stroke at 247-lbs can work on a Classic 13? That seems too heavy to me.
I've seen 40 E-TEC's on 13's and at 240-lbs, they sit very low.
Does anyone have one out there?
Moe posted 10-27-2007 04:02 PM ET (US)
Don't confuse the 3-cylinder, 747 cc, 216 pound 40 EFI that Whaler uses on the 130 Sport...
http://northamerica.mercurymarine.com/engines/outboards/fourstrokes/ enginesettwo_specs.php?ID=80
with the 4-cylinder, 995 cc, 260 pound 40 EFI BigFoot, which uses the same, apparently 31 pound heavier powerhead as the 50 and 60 HP models... as well as the apparently 13 pound heavier midsection and foot from the 75-90 HP models.
http://northamerica.mercurymarine.com/engines/outboards/fourstrokes/ enginesettwo_specs.php?ID=72
--
Moe
TRAFFICLAWYER posted 10-28-2007 04:34 PM ET (US)
The Yamaha F60 is 237 lbs. and experiences none of the Merc 60 Bigfoot issues, clunking, etc. so it appears to be a catch up in refinement rather than a one upsmanship of the competitors. The Gray cowling F60 is more aesthetic than the one on my 2005 bigfoot.

p.s. I Have a 60 Bigfoot,clunkity,klunk.
billsa posted 10-28-2007 08:16 PM ET (US)
sos - I would definitely like to know if Mercury is going to offer an "update" to fix the shifting problems on their EFI 60 four stroke bigfoot motors. I have experienced hard shifting with my unit since new - as many other I have seen post here on CW. Any idea if they will go public with any update/recall? Thanks for you your inside info.
sosmerc posted 10-28-2007 11:39 PM ET (US)
billsa...I will post as soon as I hear something meaningful. What I really need is a serial number off of any new 40,50,60hp bigfoot...as new a production date as possible. Then I can go into Merc's Parts Express site and look at the parts breakdown and compare it with older models...to see specifically what parts have been changed.
It will probably be sometime before Merc announces any retrofit kits, if they even plan to do such a thing. So far I have not heard or read anything that even implies that Merc admits there has been a problem with the previous design. (but WE certainly know there is)
frontier posted 10-28-2007 11:57 PM ET (US)
There is an article with pictures of the new 40-60 HP Merc gearcase shift enhancements on page 16 of the December 2007 'Trailer Boats' magazine.
Bensjoy posted 10-29-2007 06:04 PM ET (US)
I have a 60HP Bigfoot EFI 4-Stroke on my '68 Sakonnet. The dealer ordered the motor for me and received it in early 2007. I was told that Mercury updated the gearcases to improve the shifting on motors built beginning in the Fall of 2006. Is this true? I believe they sent a memo to dealers mentioning that all motors beginning with a particular serial number will have the updated gearcases. (The serial number of my engine is 1C035038)
jimh posted 10-29-2007 07:29 PM ET (US)
Here is the Mercury Marine press release announcing these changes. This may provide more information about the timing of the introduction:
---
June 21, 2007
FOND DU LAC, Wis. – This summer, Mercury's new 40, 50 and 60 horsepower FourStroke outboards will feature enhanced features including improved shifting and new styling.
Responding to the needs of the market, engineers at Mercury have improved the shifting, rigging and styling of this popular family of engines.
Mercury recently implemented a new shifting system on its BigFoot models, designed with more thrust and greater durability for pontoon boats. This improved design provides easier shifting with less effort from the driver. The new models also allow for easy rigging and precise throttle resolution. Mercury has incorporated the new shifting system on its new 40, 50 and 60 hp non-BigFoot models, providing the same durability and ease of use as the BigFoot models.
In addition, all of the 40, 50 and 60 hp FourStroke models will feature new styling and engine cowl graphics — matching the rest of the Mercury FourStroke product line. A new latching system provides a very simple method of removal and installation of the top cowl while also improving the cowl sealing.
The new style engines will be available for purchase in late summer through authorized Mercury dealers.
---
A2J15Sport posted 10-29-2007 09:01 PM ET (US)
The shifting smoothness will be welcome.
We have a 2000 model 75 (2-stroke) and a 2007 75 (4-stroke) both on pontoons. Both Merc's.
Both have served well but they sure do not shift as nice as similar HP John/Rudes.
By the way, the 75 four stroke is clearly more fuel efficient. We see a minimum of a 1/3 improvement. Both are on 22' "toons" of the same make. The four stroke is slightly slower. I suspect due to weight. Both are propped to run dead center of their operating WOT range.
The two stroke has over 800 hours and the four stroke is approaching 180. No complaints.
sosmerc posted 10-29-2007 11:32 PM ET (US)
I entered that serial number into Merc's Parts Express Website and does not show as a valid number....perhaps because your dealer has not registered the engine yet.
sosmerc posted 10-29-2007 11:39 PM ET (US)
It is interesting to note that Merc is only talking about improvements to the bigfoot gearcases used on the 40, 50 and 60hp models. I have always thought that the internals of the 75, 90, 115, 125 L3 and L4 and the Fourstroke 75, 90 and 115 used the same gearcase (with different gear ratios, and possibly a different driveshaft spline pattern.) It is also interesting to remember that when Honda first introduced their 90 4 stroke it came equipped with the same gearcase that Mercury was using (only with a different driveshaft). It raises the question: Who REALLY builds these gearcases anyway?.
The situation is clear as mud at this point, but I will get to the bottom of it as soon as concrete info is available. The real answers will appear when we can actually look at a parts breakdown of the NEW gearcase.

Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.

Author	Topic: Mercury Updates 40 to 60-HP Four Stroke Motors
jimh	posted 10-26-2007 09:27 AM ET (US) Mercury has introduced new designs in their four-stroke motors of 40, 50, and 60-HP. Because Mercury has dropped any designation of model years, I am unclear how to describe these motors. The nomenclature for them is unchanged. They are called the 40-HP EFI, 50-HP EFI, and 60-HP EFI four-stroke models. It is unclear when the precise manufacturing epoch began for these new motors. The changes include a new cowling style, which should make visual recognition of the new models easier. The new cowling style is said to reflect the Verado motor cowling. I believe this is a reference to the curved line of the motor which arches up from the gear case to the top of the cowling in a smooth curve. Among the changes in the new models, the most significant is a new gear case shifting mechanism. The new gear case is said to have "PRECISION ENGINEERED SHIFT." I believe that this refers to a change in the gear shift actuator to a desmodromic actuator from a cam follower and return spring actuator. Desmodromic is a mechanical engineering term which refers to a valve or control device which is operated by different mechanisms to move in different directions. A good example of a non-desmodromic valve is the typical poppet valve in a four-stroke engine cylinder intake and exhaust. The valve is opened by a cam follower and closed by the spring. A desmodromic valve has direct positive actuators for each direction of movement. Previous outboard gear case shift mechanisms tended to use a cam follower and spring return design for the shift mechanism. Apparently in the new Mercury gear case used on these 40 to 60-HP motors the shift mechanism is now desmodromic. A simpler term might be "push-pull." There is also mention that the shift mechanism has been given greater mechanical advantage in order to provide a more positive engagement. The gear cases of Mercury outboards were somewhat famous for a tendency to have a CLUNK when shifting, so it is anticipated that the improvement to the gear case shift mechanism will reduce that tendency. The cowling styling has changed, and the cowling latches have been redesigned and improved. The new latching mechanism is described as having the ability to force the cowling upward slightly when the latch is released. This loosens the cowling and makes it easier to grasp it for removal. In the past Mercury cowlings were somewhat famous for being difficult to remove due to the tenacity of the vinyl seal, which often stuck the cowling and the midsection together quite firmly. The lower lip of the new cowling design is now curved as opposed to being a straight edge. The curved cowling locates itself on the mid-section of the motor and helps align the two components. This style was first seen about five years ago in the Bombardier E-TEC motors. Another area of improvement is in the throttle linkage. The throttle control is now said to offer finer resolution of engine speed, which will be particularly helpful at low speeds used in fishing by trolling lures. The precise changes in the engine graphics are not apparent. It would be good to get more detail about the graphics inasmuch as the visual appearance of this motor will be key to identifying it as a new and improved model. If anyone has information about the exact date when the new motors replaced the obsolete models, or a serial number range when the new motor production began, it would he very useful to have this information available to potential buyers. In this way a buyer could more positively determine what motor he was buying, new model or leftover old model. The 40 to 60-HP Mercury four-stroke motors are of moderate weight (247-lbs or 112-kg) and find application in classic Boston Whaler boats like the 13-foot and 15-foot hulls. These motors have the Mercury electronic fuel injection and advanced Mercury ECM 555 digital inductive ignition. These excellent features have already set these motors apart from competitor's engines in this horsepower range. These further refinements should make these motors more attractive.
sosmerc	posted 10-26-2007 11:52 PM ET (US) Hard shifting on these models (and all other models that have basically the same gearcase such as 75/90/115 Optimax and F115 EFI) has been a known problem for some time. Merc is finally addressing the issue and I have been trying to find out specifically what they have changed. I just got off the phone yesterday with one of my contacts that has "contacts" at Merc and he was trying to find out for me some specifics. He spoke with two different people at Merc and all they would say was that a cam change had been made. My hope is that whatever changes they made, can be made to previous units as an "upgrade". I have several customers with Bigfoot lower units that can barely be shifted from forward to neutral with the engine running. Been waiting some time for a fix.
L H G	posted 10-27-2007 12:14 AM ET (US) Here's Mercury's performance report to go with Jim's article. http://www.mercurymarine.com/look_deeper/head_to_head.php?ID=52& Filter=11
jimh	posted 10-27-2007 01:07 AM ET (US) I found some previous literature from Mercury which mentions that the gear case on the 75, 90, and 115-HP motors was using a desmodromic shift actuator in c.2005 models.
sosmerc	posted 10-27-2007 11:32 AM ET (US) Merc changed to a desmodronic shift mechanism on their V-6 gearcases (2.0 and 2.4 litre) in the very early 80's. They called it "EZ shift". They have not used this design on anything else up to this point. All the L3 and L4 gearcases have a pin that rides against a cam. The cam rotates and pushes the pin. The "profile" of the cam has alot to do with the effort required to shift. Also, the design and number of dogs on the clutch and gears will greatly affect the shifting effort...especially when the engine is running developing torque.
macfam	posted 10-27-2007 02:46 PM ET (US) jimh, Do you think that the weight of the 40 EFI 4-stroke at 247-lbs can work on a Classic 13? That seems too heavy to me. I've seen 40 E-TEC's on 13's and at 240-lbs, they sit very low. Does anyone have one out there?
Moe	posted 10-27-2007 04:02 PM ET (US) Don't confuse the 3-cylinder, 747 cc, 216 pound 40 EFI that Whaler uses on the 130 Sport... http://northamerica.mercurymarine.com/engines/outboards/fourstrokes/ enginesettwo_specs.php?ID=80 with the 4-cylinder, 995 cc, 260 pound 40 EFI BigFoot, which uses the same, apparently 31 pound heavier powerhead as the 50 and 60 HP models... as well as the apparently 13 pound heavier midsection and foot from the 75-90 HP models. http://northamerica.mercurymarine.com/engines/outboards/fourstrokes/ enginesettwo_specs.php?ID=72 -- Moe
TRAFFICLAWYER	posted 10-28-2007 04:34 PM ET (US) The Yamaha F60 is 237 lbs. and experiences none of the Merc 60 Bigfoot issues, clunking, etc. so it appears to be a catch up in refinement rather than a one upsmanship of the competitors. The Gray cowling F60 is more aesthetic than the one on my 2005 bigfoot. p.s. I Have a 60 Bigfoot,clunkity,klunk.
billsa	posted 10-28-2007 08:16 PM ET (US) sos - I would definitely like to know if Mercury is going to offer an "update" to fix the shifting problems on their EFI 60 four stroke bigfoot motors. I have experienced hard shifting with my unit since new - as many other I have seen post here on CW. Any idea if they will go public with any update/recall? Thanks for you your inside info.
sosmerc	posted 10-28-2007 11:39 PM ET (US) billsa...I will post as soon as I hear something meaningful. What I really need is a serial number off of any new 40,50,60hp bigfoot...as new a production date as possible. Then I can go into Merc's Parts Express site and look at the parts breakdown and compare it with older models...to see specifically what parts have been changed. It will probably be sometime before Merc announces any retrofit kits, if they even plan to do such a thing. So far I have not heard or read anything that even implies that Merc admits there has been a problem with the previous design. (but WE certainly know there is)
frontier	posted 10-28-2007 11:57 PM ET (US) There is an article with pictures of the new 40-60 HP Merc gearcase shift enhancements on page 16 of the December 2007 'Trailer Boats' magazine.
Bensjoy	posted 10-29-2007 06:04 PM ET (US) I have a 60HP Bigfoot EFI 4-Stroke on my '68 Sakonnet. The dealer ordered the motor for me and received it in early 2007. I was told that Mercury updated the gearcases to improve the shifting on motors built beginning in the Fall of 2006. Is this true? I believe they sent a memo to dealers mentioning that all motors beginning with a particular serial number will have the updated gearcases. (The serial number of my engine is 1C035038)
jimh	posted 10-29-2007 07:29 PM ET (US) Here is the Mercury Marine press release announcing these changes. This may provide more information about the timing of the introduction: --- June 21, 2007 FOND DU LAC, Wis. – This summer, Mercury's new 40, 50 and 60 horsepower FourStroke outboards will feature enhanced features including improved shifting and new styling. Responding to the needs of the market, engineers at Mercury have improved the shifting, rigging and styling of this popular family of engines. Mercury recently implemented a new shifting system on its BigFoot models, designed with more thrust and greater durability for pontoon boats. This improved design provides easier shifting with less effort from the driver. The new models also allow for easy rigging and precise throttle resolution. Mercury has incorporated the new shifting system on its new 40, 50 and 60 hp non-BigFoot models, providing the same durability and ease of use as the BigFoot models. In addition, all of the 40, 50 and 60 hp FourStroke models will feature new styling and engine cowl graphics — matching the rest of the Mercury FourStroke product line. A new latching system provides a very simple method of removal and installation of the top cowl while also improving the cowl sealing. The new style engines will be available for purchase in late summer through authorized Mercury dealers. ---
A2J15Sport	posted 10-29-2007 09:01 PM ET (US) The shifting smoothness will be welcome. We have a 2000 model 75 (2-stroke) and a 2007 75 (4-stroke) both on pontoons. Both Merc's. Both have served well but they sure do not shift as nice as similar HP John/Rudes. By the way, the 75 four stroke is clearly more fuel efficient. We see a minimum of a 1/3 improvement. Both are on 22' "toons" of the same make. The four stroke is slightly slower. I suspect due to weight. Both are propped to run dead center of their operating WOT range. The two stroke has over 800 hours and the four stroke is approaching 180. No complaints.
sosmerc	posted 10-29-2007 11:32 PM ET (US) I entered that serial number into Merc's Parts Express Website and does not show as a valid number....perhaps because your dealer has not registered the engine yet.
sosmerc	posted 10-29-2007 11:39 PM ET (US) It is interesting to note that Merc is only talking about improvements to the bigfoot gearcases used on the 40, 50 and 60hp models. I have always thought that the internals of the 75, 90, 115, 125 L3 and L4 and the Fourstroke 75, 90 and 115 used the same gearcase (with different gear ratios, and possibly a different driveshaft spline pattern.) It is also interesting to remember that when Honda first introduced their 90 4 stroke it came equipped with the same gearcase that Mercury was using (only with a different driveshaft). It raises the question: Who REALLY builds these gearcases anyway?. The situation is clear as mud at this point, but I will get to the bottom of it as soon as concrete info is available. The real answers will appear when we can actually look at a parts breakdown of the NEW gearcase.