2005 Mercury 60 EFI lugging

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supagruv
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2005 Mercury 60 EFI lugging

Postby supagruv » Wed Dec 30, 2020 8:39 pm

I got a used 2005 Mercury 60-HP EFI FOURSTROKE BIGFOOT SN 1B004844. Overall the engine is in excellent condition. The engine seemed to run fine when we ran it on muffs. When in the water and with load, the Mercury 60-HP FOURSTROKE EFI BOGFOOT is missing and lugging.

The engine cannot accelerated past 3,500-RPM.

When we brought the boat home we had the local Mercury shop connect their computer; the runtime was 509-hours. No [fault or service] codes showed up, except something in 2019 showing signs of a spun propeller hub. We installed a new propeller.

I [replaced or serviced] thermostat, water pump, impeller, spark plugs, fuel filters, and fuel lines. I just checked the spark plugs. They all are clean and have no black or white or gray. They look like new.

I've read through the manual and looked at the entire spark plug, coil pack, and wiring area to see if there were any signs of wear, chafing, and corrosion; everything looks clean.

I also tried bench-testing the coil packs with my multimeter; they seem to show the right resistance reading. The manual shows four wires and my engine has five wires going to each coil. I was able to get a reading from the two right-most connectors.

I did see that there was a service bulletin on these engines regarding the coil packs: they should be replaced to fix [running problems] like [this engine exhibits]. A recall ended in 2015, and I must pay full price or contact Mercury directly in hopes they have sympathy.

I'm not a mechanic, but I do my best to read the manual and perform the tests that my basic tools allow. If the engine were in a car, I would pull codes [presumably using an ADB-II code reader] and determine which cylinder was misfiring. Then I would try swapping coil packs with a known good one. But that doesn't quite seem possible with an outboard engine that needs to be run in the water to reproduce the fault.

I would greatly appreciate any suggestions.

ASIDE: I ordered a set of coil packs. We're here in Hawaii. To get them may take [until about January 14, 2021]. [Buying the coil packs] feels like throwing money at the problem and crossing your fingers.

ASIDE: I've found this forum to be helpful in recent months, but this is the first time I've felt the need to ask for help.

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Phil T
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Re: 2005 Mercury 60 EFI lugging

Postby Phil T » Wed Dec 30, 2020 9:33 pm

I would proffer that given the symptoms and work done, I suspect [the cause of the lugging will be due to] the injectors.

The injector sprays a very fine spray of fuel into the cylinder. The screens and small passages in the injector can get dirty to vlogged. This reduced flow shows as the engine bogging down under load at around 3,000-RPM.

Given you want the engine to be up to date on all maintenance, and given its age, I would send out all the injectors to be professionally cleaned and tested. All dealers send injectors out to a professional shop. I used Flagship in Florida.

http://flagshipengine.com/catalogpages/18/page18.htm

If the injectors are cleaned and the problem is not solved, the cleaning was not in vain.
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1992 Outrage 17, 1992 Evinrude 115

jimh
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Re: 2005 Mercury 60 EFI lugging

Postby jimh » Thu Dec 31, 2020 4:25 pm

When Mercury denotes an outboard engine as having "EFI" is could mean anything from having one injector crudely controlled by the throttle linkage to something more sophisticated, but short of having direct fuel injection into each cylinder by a dedicated injector.

If there is a Mercury Service Bulleting announcing that the spark coils will be replaced due to defect for no charge under warranty, whether or not that offer is still available, the offer indicates there is a very likely correlation between problems with the engine running performance and the spark plug coils. On that basis, I would purchase new spark plug coils and see if they resolve the engine running problem.

Unless the spark coils are outrageously priced, the cost of one coil will be far less than one hour of technician service time. The spark coils should be easy to replace, and they should not require any adjustments.

Spark plugs that have run for perhaps 20-hours and show NO SIGN of soot or combustion are probably spark plugs that NEVER fired.

A typical problem that causes an engine to lug or to stumble or to hesitate when trying to accelerate under load is SPARK GAP distance that is too large. Check the spark gap on all the spark plugs. This is easily done and is a very simple test. Spark gap distance that is too large causes the spark to fail to ignite the fuel-air mixture in the cylinder into combustion. Of course, weak spark voltage may cause no spark at all, also causing a failure of the cylinder to ignite into combustion all of the fuel-air mixture.

An outboard engine from c.2005 will not have an ADB-II compliant controller interface. You will have to rely on your own skills to make a diagnosis.

Typically an engine that cannot accelerate under load is losing a cylinder (or two). If loss of a cylinder is related to loss of spark, you can easily test under load with an in-line spark tester. I suitable test device is made by Lisle. See

https://www.summitracing.com/parts/lil-20610

ASIDE: testing an engine under no load really proves nothing except that the engine could start and run. An engine with several dead cylinders will still be able to accelerate easily under no load. That an engine could accelerate under no load proves nothing except the engine could start and the crankshaft, pistons, and connecting rods were not bent or jammed.

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Re: 2005 Mercury 60 EFI lugging

Postby jimh » Thu Dec 31, 2020 5:29 pm

Phil T wrote:The injector sprays a very fine spray of fuel into the cylinder.


PHIL--an injector only sprays fuel into a cylinder if the engine used DIRECT INJECTION. With c.2005 Mercury four-stroke-power-cycle outboard engines there is absolutely NO CHANCE that the engine used an advanced mechanism like direct injection. The use of the acronym "EFI" by Mercury on their outboard engines generally means a very simple fuel metering system under electronic control that sprays fuel into the air stream that is heading toward a cylinder. The fuel is not sprayed directly into a cylinder.

Don SSDD
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Re: 2005 Mercury 60 EFI lugging

Postby Don SSDD » Fri Jan 01, 2021 9:13 am

You say you have a manual, but the manual doesn’t agree with your engineon the number of wires for the coil pack,.

If your manual is not a Mercury factory service manual for your year, model, and serial number, I’d suggest you find one. The generic manuals like Clymer are usually not completely accurate for a specific outboard.

A 2005 epoch was the early years for a Mercury "FOURSTROKE" and for fuel injection. They were making changes each year and each model with these outboards on things like coil packs. From what Jim says about injectors, I’d say these were changing quickly too. Having exactly the correct shop manual will be important.

Early Mercury FOURSTROKE model outboard engines were supplied by Yamaha for several years. Some components were Yamaha, some Mercury on them. That arrangement ended in the early 2000’s, but I believe a 2005 60-HP would be one of the earlier all-Mercury FOURSTROKE engines.
1986 Outrage 18 with 2001 Honda 130 HP
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Former owner 1987 Montauk with 1998 Mercury 90HP
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jimh
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Re: 2005 Mercury 60 EFI lugging

Postby jimh » Fri Jan 01, 2021 9:43 am

Don SSDD wrote:From what Jim says about injectors, I’d say these were changing quickly too.


I am not clear that I said anything about changes in fuel injectors in a particular model of Mercury four-stroke-power-cycle engine.

What I will say about that topic: when Mercury first used the term "EFI" it was back in the 1980's. The "EFI" designator was used to differentiate engines using fuel-injectors from the classic carburetor engines. It was common for engines denoted as "EFI" to just have a fuel injector that was controlled in a somewhat simple manner to spray fuel into the air stream that was heading for the cylinder, so there really was not much "injection" but that word sounded better than "fuel spraying."

Use of direct injection of fuel into the cylinder was not done on most four-stroke-power-cycle outboard engines. Ironically, direct fuel-injection was used with two-stroke-power-cycle outboard engines like the Mercury OptiMax, the Evinrude Ficht, and the Evinrude E-TEC. Direct-injection has only recently come into use in automobile four-stroke-power-cycle engines, probably to improve performance of small-displacement engines and to help meet emission controls.

As noted, Mercury entered into a partnership with Yamaha to develop four-stroke-power-cycle outboard engines. Mercury's contribution to this partnership was to cast the aluminum engine blocks and ship them to Japan for Yamaha to finish into outboard engines. There really was no "all-Mercury" four-stroke-power-cycle engine except perhaps for a 25-HP model for many years.

At some point, Mercury outboard engine production of all engines 75-HP or less was moved offshore, and the engines were being built in China, as I recall. I don't recall the exact epoch when that began.

Generally a way to recognize an outboard engine as "all-Mercury" is by the descriptor "Smartcraft." Mercury engines with Smartcraft tend to use Mercury developed engine control systems. Yamaha-made Mercury engines would not have a Smartcraft designator because the engine electronic controller was made by Yamaha.

Advice to get a factory service manual is good advice. Non-OEM service manuals published by others often tend to have a lot of material known in the technical publishing business as "boilerplate." Boilerplate is a term for generic material that can be "unbolted" from one publication and added to another because it is not model-specific. Using a lot of boilerplate is a way to make thicker manuals that really do not contain much greater information than they would without the boilerplate. (Here I am speaking from experience as a technical writer who prepared technical manuals for a living. Our company loved boilerplate because it made for more impressive manuals, that is, manuals with more pages.)

supagruv
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Re: 2005 Mercury 60 EFI lugging

Postby supagruv » Fri Jan 01, 2021 4:42 pm

I highly appreciate all your posts. To have experts chime is good.

I removed the injectors the other day and inspected and cleaned them. They did have a lot of black junk around the rim of the nozzles which didn't look good. I've ordered a set of new injectors and they should get here in a week or two.

Initially I did find a PDF manual for a 2001 Mercury 60 EFI. It proved helpful in doing standard maintenance and rebuilding the trim cylinder.

When the coil wire harness showed a wrong number of wires, I went online and paid $20 for what sounded like an OEM Mercury manual. That manual was mostly identical to the one I already had. I guess I need to get a real OEM manual

I have ordered the set of spark coils. They should be here in a few days. I can install them in place of the coils in use now.

The manual has test procedures that I am planning to run through.

ASIDE ON A DIFFERENT ENGINE: To figure out all the problems in my Yamaha 150 took time. In contrast, this 2005 Mercury 60-HP FOURSTROKE EFI engine in such good condition I think [finding the cause of the running problem and replacing the defective component] must be a simple [job] like replacement of the spark coils.

I will append an update soon.
Last edited by supagruv on Fri Jan 01, 2021 6:02 pm, edited 1 time in total.

supagruv
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Re: 2005 Mercury 60 EFI lugging

Postby supagruv » Fri Jan 01, 2021 6:00 pm

The original spark plugs were OEM Champion RA8HC with a 1.00 mm gap, and they were worn looking and rusty at the bases.

I could not get the Champion plugs, and I put in NGK DCPR7E.

I just checked the gap and it's only 0.80 mm on the NGK plugs.

Would [a change in spark plug gap to 0.80 mm from 1.00 mm make a big difference?

I had an "aha moment" when I figured this out, but then I remembered that the engine with the OLD plugs and the NEW plugs had the same running problem. I doubt [the spark plug gap change] is the entire problem.

What do you think?

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Re: 2005 Mercury 60 EFI lugging

Postby jimh » Fri Jan 01, 2021 11:00 pm

There seems to be a sort of fascination with NGK-brand spark plugs, and some people seem to think an NGK plug is always going to be better than the OEM plug. I don’t know if the NGK plug you used is an exact replacement for the OEM Champion plug.

I would use the OEM plug, not an “equivalent” non-OEM plug.

I would set the spark plug gap to the exact distance specified in the OEM manual.

I would get a $12 Lisle spark tester and compare the spark strength among cylinders.

How many cylinders goes this engine have?

dtmackey
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Re: 2005 Mercury 60 EFI lugging

Postby dtmackey » Mon Jan 04, 2021 9:25 am

supagruv wrote:The original spark plugs were OEM Champion RA8HC with a 1.00 mm gap, and they were worn looking and rusty at the bases.

I could not get the Champion plugs, and I put in NGK DCPR7E.



That Champion plug is available at any automotive store - visit Autozone, NAPA or Advanced Auto parts and they run $2.19 - 2.49 each. The NGK equivalent plug, if listed in a cross ref table by NGK is a pretty good match to the Champion, but I am highly doubtful this would cause your problem. I'm leaning on an ignition concern upstream of the plug or a fuel delivery concern, which could also be caused by a sensor that is bad (out of tolercance) causing the ECU to provide bad decisions to your fuel and spark curve maps.

D-

Don SSDD
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Re: 2005 Mercury 60 EFI lugging

Postby Don SSDD » Mon Jan 04, 2021 12:32 pm

The correct factory service manual will also list available recommended spark plugs. Normally if they are recommended in the manual, they also come pre-gapped to the correct spec. You still should check the gap when buying new plugs.

In my experience, some motors only run well on original spec plugs, other motors will run better on alternative plugs, you'd only find this out for your motor by using different plugs, I've had good luck with NGK plugs. I also agree that your current problems are not likely related to plugs.
1986 Outrage 18 with 2001 Honda 130 HP
Former Owner 1991 Guardian 19 with 1994 Evinrude V4 140HP
Former owner 1987 Montauk with 1998 Mercury 90HP
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pshosho
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Re: 2005 Mercury 60 EFI lugging

Postby pshosho » Mon Jan 04, 2021 2:48 pm

All good suggestions here, but I experienced similar performance problems with nearly the same motor last summer, so I wanted to share my story.
I have 2002 Mercury 4-stroke EFI Bigfoot motor. It would run smooth at idle and slow speeds but would not exceed 3,000 RPM underway and would sputter back to idle. I figured it was a fuel concern but I had fresh fuel in the tank. I replaced the fuel filter (water separator) mounted in the engine well, replaced the fuel line (Montauk 170) which was due anyway and both fuel filters inside the motor. This still did not resolve the problem.
At that point I was thinking the same things as in the posting above, injectors and/or coil. But if you use to Google to get an idea of the frequency of problems most often encountered with this model line, injectors really don't have many postings and the coils were initially a bad batch but after a number of replacements in the early years, postings of problems appear to be infrequent. What is frequently searched and repaired is the VST (Vapor Separation Tank). There are YouTube videos showing the disassembly on the same motor. So I removed my VST in about an hour and then took it apart. Sure enough it was full of brown slime, which was clogging the screen at the base of the high-pressure fuel pump. I cleaned the tank thoroughly with carburetor cleaner. I decided to replace the fuel pump because it was 18 years old and bought a new gasket for the VST. Reassembly and reinstallation was another hour. Launched the boat and she cruised up the maximum speed as it should so problem fixed.

So if you have never opened up the VST on your 2005 Mercury 60, it might be time to clean it out. The cost of a new gasket is very low and you only have wasted two hours if you find the inside of the VST if very clean, then you can move to the injectors or coils.

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Re: 2005 Mercury 60 EFI lugging

Postby biggiefl » Mon Jan 04, 2021 3:05 pm

That is a great suggestion about the VST and most likely the cause.

If you do not open the coil packages, you should be able to return them if unopened.
On my 24th Whaler. Currently in the stable: 86 18' Outrage, 81 13' Sport(original owner), 87 11' Sport, 69 Squall(for sale cheap).

supagruv
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Re: 2005 Mercury 60 EFI lugging

Postby supagruv » Mon Jan 04, 2021 3:29 pm

I really appreciate everyone's feedback and all the sharing of knowledge going on. I feel wiser with every step and with any luck am closer to a solution.

I replaced the NGK plugs with the OEM Champion ones and gapped them to be 1-mm as per the manual.

I installed a new fuel filter on the starboard side near the top of the engine about 14-days earlier.

I also checked the [fuel filter located] on the port side on the bottom of the engine cover by the fuel line intake. I couldn't determine if it was old or was dirty, but it wasn't obstructed.

I removed the [fuel-vapor separator tank] (VST) about seven days ago. The VST was actually really clean. and so was the filter at the bottom of the fuel pump. The VST gasket was in good condition as well.

Considering this engine is from 2005, the fuel pump is most likely the original 16-year-old fuel pump, and replacing the fuel pump may be worthwhile.

As I said in my previous post, when I removed the injectors they had some black gunk on them which did make me think the VST could [have some undescribed relationship between to the appearance of the fuel injectors]. [Please elaborate what relationship there would be between the VST and black gunk on the injectors--Moderator].

My plan is to run the engine on January 5, 2020, first on the [a hose adaptor with no load on the engine] and then in the bay [with a load on the engine].

In the future I will report [the outcome of the January 5, 2020 testing on the hose adaptor and on the water].

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Re: 2005 Mercury 60 EFI lugging

Postby jimh » Tue Jan 05, 2021 12:23 pm

As I mentioned earlier, an engine that has lost combustion in one or maybe even two cylinders will still be able to accelerate without any load on the engine to an engine speed of thousands of RPM, probably fast enough to damage the engine if allowed to accelerate to beyond the recommended maximum engine speed. This makes testing the engine on a hose adaptor with no load to be a rather uninformative test to perform.

In this thread the problem is the engine cannot accelerate to much engine speed under load; it can only reach 3,500-RPM.

If we assume the cause of this problem is due to one cylinder losing combustion, then the remedies applied so far are remedies that affect all cylinders equally. New spark plugs in all cylinders and new fuel filters are remedies that will be common for all cylinders. They won't be likely to fix a problem that was isolated to one cylinder.

As I suggested earlier, you should check the spark on the cylinders individually when the engine is under load using a spark gap tester.

An even more rudimentary test of individual cylinder spark can be done by disconnecting the spark plug lead from the spark plug while the engine is running, and observing for a change in engine speed. Disconnecting the spark plug lead from the spark plug should halt combustion in that cylinder, which should immediately cause the engine speed to decrease. There are two cautions: wear insulating gloves and use an insulating tool to remove the spark plug lead or you will get quite a jolt from the spark current running through your body; and check the service manual to see if this procedure is warned against. It might be possible to damage the spark plug coil or the spark controller mechanism if there is no load on a spark plug lead. Some engines specify that a spark plug lead must be connected to a substitute load so the energy of the spark current can be dissipated into a resistor and an air-gap.

If that is the situation with the engine under discussion, you should shut off the engine, remove the plug lead and connect it to the dummy load, then restart and see if the engine speed changed. Or cross your finders and try it live--but read the factory manual for advice before doing that.

supagruv
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Re: 2005 Mercury 60 EFI lugging

Postby supagruv » Wed Jan 06, 2021 2:40 pm

Good News!!! I installed the set of new coils and immediately the motor ran smoother on the muffs (less vibrations) and when idling into higher rpms it was significantly quieter. We took the boat out in the bay and it now runs GREAT! WOT to nearly 6k rpms! What a relief... I was beginning to think there may have been a "ghost in the machine" or something...

Anyway, thanks for everyone chiming in and especially for sharing all of your knowledge about how the systems work and conceptual troubleshooting as well. It's much appreciated!