2018 E-TEC 90-HP Engine Surges

[glen1941]

The 2018 E-TEC 90-HP engine on my 1989 GLS 17 is surging.

Q1: what could cause this behavior?

BACKSTORY

Recently an Evinrude Platinum dealer installed all new fuel hoses, new 6-gallons fuel tanks, an in-line fuel filter, a new VST filter, and a RACOR fuel-water separating filter. After that service the boat rand well.

Very recently the E-TEC 90-HP engine was started and set at idle speed at home and later at a dock. When the boat headed out from the dock the engine began to surge.

I characterize this as engine speed increasing, then decreasing without any change in throttle position; finally the engine quit. Squeezing hard on the new fuel line primer bulb seemed to work sometimes, although, it would take many starting attempts to get motor running at idle and low speed. With the cowling off, I noticed that there was no fuel in inline filter [strong clue]. Finally made it back to dock.

TRIM SYSTEM
This 2018 E-TEC 90-HP engine--which was previously examined in every way by an Evinrude dealer before purchase--has now begun to drop to lowest position after being tilted up. Until recently, it was a very slow drop, now almost immediate.

I have read about unscrewing the manual release screw and cycling the trim several times, and also having the engine stopped from tilting down while activating the "down" tilt control. Will try both today.

[jimh]

A general cause of engine speed change without throttle setting change is likely to be related to lack of fuel.

There could be air in your fuel system.

Your observation of lack of any fuel in a fuel filter suggests lack of fuel is responsible.

For best advice on diagnosis of running problems with an E-TEC engine, I recommend you move to the website

https://ETECOWNERSGROUP.COM

Choose the proper forum for posting according to your engine number of cylinders (V4 or Inline3) and whether a legacy model or a G2 model. Include the complete model number in your first post there. You will get expert advice from that resource.

[glen1941]

After many phone calls to repair shops and hours of research, the consensus [opinion of the cause of the engine surge problem] was a failed high pressure fuel pump. The existing electric pump was reading only 5 to 6-PSI at the high pressure test point. This diagnosis also indicated that the mechanical low-pressure fuel lift pump was working.

I first replaced the existing pump with a new after-market quick-disconnect pump, which then also read 7 to 8-PSI after squeezing the primer bulb as hard as possible. Deciding that the [problem's causes] were both the old and new electric high pressure pump, I set about replacing [the after-market high-pressure pump] witha new [OEM Walbro] high-pressure pump and separate vapor-fuel separator tank (VST).

While doing that, I saw that the wires carrying power to the electric pump had been severed from chafing by the taking off and putting on of the cowling. This was not apparent in the beginning as those wires were behind some of the other stuff.

The [E-TEC outboard engine] with the new Wallbro integrated pump and VST now goes zoom zoom.

However, because the new Walbro high-pressure fuel pump does not have a pressure test fitting, I will tie [the 1989 GLS 17 boat] to the dock and run the [E-TEC 90-HP engine] for quite a while [to prove the repair has eliminated the original problem of the engine surging].

[jimh]

Thanks for the follow-up that describes the cause of the 2018 E-TEC 90-HP (presumably the three-cylinder in-line legacy model) whose engine speed was surging and the remedy to the problem: a new high-pressure OEM-style Walbro fuel pump and VST assembly.

ASIDE
If the wire insulation chaffing of the electrical power to the original high-pressure fuel pump and VST assembly also caused some of the strands of the wire to be cut, then the resistance in the wire could have increased. With increased resistance in the wire supplying the electrical current to the pump motor, the speed and torque of the electric motor in the pump could have been reduced. This could have caused the reduction in fuel pressure in the fuel distribution manifold, and that could have caused the engine speed to slow and surge, as you reported as the original symptom.

Q2: did you make any repair to the wire conductors that showed chaffing?

[glen1941]

Hello Jim,
The wires to the electric pump were completely severed, so no power was getting to the pump. The wires are extremely thin and encased in a black mesh sleeve making it very hard to see that the wires had come apart. I stripped about 1" of insulation from the wires, wrapped the wires together, soldered the wires and then pulled the heat shrink tube over the joints. The original electric pump might have worked if only the wires had been repaired, but that is history [$$$] now. The wires are now rerouted to keep them safe from chafing.

[jimh]

Generally on an E-TEC engine (that has not been running for a while), when the ignition key switch is moved to ON from OFF, the high-pressure fuel pump electric motor is energized and runs for five seconds or longer until the high-pressure fuel distribution system has been pressurized to the normal pressure level. The minimum high-pressure level is specified as between 24 to 28-PSI and is noted in the SERVICE MANUAL.

Even with the E-TEC engine cowling in place, if you are close to the engine the sound of the pump motor running will be audible. Not hearing the fuel pump run would be a very unusual cold start condition.

I checked the SERVICE MANUAL for my E-TEC V6 225-HP engine, and found that the EMM is capable of detecting a service code 91 FUEL PUMP CIRCUIT OPEN. Checking the service manual for the 2010 90-HP E-TEC, there is also a notice that service code 91 FUEL PUMP CIRCUIT OPEN will be provided.

Also, if the circuit for the fuel pump motor were shorted, that is also noted by service code 94 FUEL PUMP CIRCUIT SHORTED.

On that basis, if you had the E-TEC EV-Diagnostic software and the appropriate terminal to host the software and the appropriate serial port and the appropriatei nterface cable, you could have run the EV-Diagnostic software and gotten an engine history report, and if the circuit to the fuel pump were either open or shorted, you would have been pointed right at that fault condition.

The EMM in the E-TEC engine is rather smart and often provides very useful data about non-standard events in the engine operation history. For example, the EMM in my V6 E-TEC 225-HP alerted me to a ignition spark coil for a particular cylinder that was in a non-standard condition, and upon investigation I found that coil had developed a short to ground for the high-voltage secondary winding. That was extremely useful diagnostic information from the EMM.

If you plan to own and self-maintain an E-TEC engine, having factory Service Manual and the EV-Diagnostic software are really essential tools.

Also, even without the EV-Diagnostic software, the circuit to the high-pressure fuel pump electric motor is available on a two-pole connector. The pump could easy be disconnected from the EMM circuit, and then using an Ohmmeter you could read the resistance of the pump motor winding. Of course, if the open circuit due to chafing were not in the short wiring from the pump to the connector, you would not get an open or short circuit reading,

Of course, once the problem source has been identified, it is simple to see how the faulty component might have been discovered by other means that the actual method used in the repair.

[jimh]

The wires to the electric pump...are extremely thin...

The fuel pump operates from the 12-Volt battery bus in the E-TEC so it probably draws a few Amperes of current. The wire size shouldn't be particularly small. Most of the wiring is at least 16-AWG.

If you could give the wire size in AWG number that corresponds to "extremely thin" then your description of the wire conductor gauge would be more precise.

[glen1941]

jimh—Yep, hindsight is 20/20.

The "very thin" wire in this case is something like half the diameter of the lead in a mechanical pencil. My strip, cut and crimp tool worked at 23.

I really do not don't want to learn more technology at this time, but see that I must get outfitted and knowledgable with the EV-Diagnostic software for any future [engine problems].

I now have a [repeat customer] relationship with Barnacle Bill's so will start [looking for the EV-Diagnostics software and special cable] there--unless you have better idea.

The remaining engine problem keeping me out of the water is the tilt and trim. All worked well until recently, motor runs, no visable leaks at ram, switches work. Internet points to manual release valve. Replaced with $130 aftermarket from Five Star marine, did not work.

I have purchased a new OEM [trim unit manual release valve] from BB's, and I hope it will be the answer.

[jimh]

For more advice on what is needed to use EV-Diagnostics software, see my article at

EV-Diagnostics Software
https://continuouswave.com/forum/viewtopic.php?t=4706

[jimh]

The "very thin" wire in this case is something like half the diameter of the lead in a mechanical pencil. My strip, cut and crimp tool worked at 23.

If you mean "23" as in AWG-23, that is an extremely small diameter conductor. That seems very unusual.

[jimh]

Also, another question:

Q3: was the break in the circuit that needed repair on the part of the circuit from the pump assembly to the connector, or other side, from the mating connector to the EMM?

[jimh]

The fuel pump operates from the 12-Volt battery bus in the E-TEC so it probably draws a few Amperes of current.

This statement is not quite correct. The power source for the fuel pump depends on the engine model. In the smaller engines, like a 90-HP, the power source is from the 55-Volt bus, probably with a pulsed power so that the effective voltage is more like 12-Volts. In the larger engines, like my V6, the fuel pump is powered by the 12-Volt bus, so the wiring is probably sized to handle more current.

Also, perhaps the electric motor voltage changes, too. Comparing the part numbers for the pump-VST assembly for the in-line engine and the V6 engines would be interesting.

[jimh]

Generally on an E-TEC engine (that has not been running for a while), when the ignition key switch is moved to ON from OFF, the high-pressure fuel pump electric motor is energized and runs for five seconds or longer until the high-pressure fuel distribution system has been pressurized to the normal pressure level.

Again, this statement is not quite correct. Upon further investigation, in the in-line three-cylinder engines (like a 90-HP) the fuel pump motor ONLY operates if the engine is cranking over or is running. This is because the power comes from the 55-Volt bus, not from the 12-Volt bus (running off the battery power). So listening for the pump to run before starting the engine with a 90-HP or 75-HP would not be possible.

Refer to the 90-HP engine SERVICE MANUAL, FUEL SYSTEM COMPONENTS section, FUEL CIRCULATION PUMP sub-section, ELECTRICAL CIRCUIT paragraph.


On the V6 engines the pump runs from 12-Volt battery power, so it can pre-pressurize the fuel distribution manifold before actually cranking over the engine.

ASIDE: perhaps that is why the V6 engines start after about one-revolution of the crankshaft, as the fuel distribution manifold could have been already at operating pressure before the operator moves the ignition key switch to START from ON, assuming he delayed for a few seconds with the switch left in the ON position before trying to start the engine. This is my usual starting procedure because I typically have just launched the boat off the trailer, and the engine was in a trimmed-up position to avoid any possible contact with the ramp surface during launching. When ready to start, I first turn the key to ON in order to use the TRIM control at the helm to tilt-down the engine so the gear case is submerged. That lets the fuel system come up to pressure. Then the engine starts so rapidly it almost scares you.

[glen1941]

Jim--I can only tell you that the wires come from somewhere in the dark recesses of the engine, concealed in a black mesh sheaf, and connect to the high pressure fuel pump. They are very thin. My first thought was, how am I going to join these wires together, but the internet saved me.

If I had been clever enough, and had the benefit of the [EV_Diagnostics software] gizmos, I would have chased down that the fault was the severed wires. I would not have spent the [a lot of] money and effort to remove the old non-integrated pump and tank and to have installed the new Walbro integrated assembly.

From hours of reading, I have arrived at a procedure of turning the ignition to "on" and holding there for the lights to come on, and for at least 5 seconds. Not sure what is going on here, but it works. My E-TEC 90-HP engine starts instantly, faster than my Honda Ridgeline, and as fast as the 6BTAs in the Hatteras I had years ago.

The tilt and trim repair is headed towards success --I hope. I have ecided that the best path forward was to remove the hydraulic assembly in order to be able to install the manual release valve in a more straightforward manner. Also, After installing the new valve, I will cycle the ram to confirm that the thing works before reinstalling the assembly.

On a related subject:

Q4: what is the best equipment to purchase to join the diagnostic club?

I am a MacOS Apple person.

There are "kits" with wires and flash drives on eBay, and I guess I will have to buy a Windows laptop.

Please recommend how I should proceed to have a setup which allows me to begin learning to use the software.

Thank you, Glen

[glen1941]

The tilt trim problem is resolved. The main cause of the failure was a faulty manual release valve.

The initial symptom of the problem was when the E-TE 90-HP engine would gradually drift down from a tilted-up orientation. Eventually the engine would trim up and not trim down. I installed a new manual release valve and that did not work.

Then I removed the entire hydraulic assembly to be able to work on it on my work bench. I installed the new (Five Star brand) manual release valve. I set up the hydraulic assembly close to the E-TEC engine, and I jumpered power cables to allow temporary operation. I tried making the ram go up. At first nothing, after many tries, the ram finally began to move. Each time the ram advanced more, each time I would lubricate the ram and add more hydraulic fluid. Eventually, the ram would move completely up and completely down without noise from the electric motor or assembly internals.

The electric trim motor did become very hot.

After much discussion with the great folks at ReelLoco in Pompano Beach, Florida, the diagnosis was the ram seals and pump motor were normal, and that proof would be if the ram would support the full weight of E-TEC 90-HP engine and move the the engine up and down.

No one had an opinion about the trim unit behavior when the problem had first appeard.

After much work installing the hydraulic trim-tilt assembly back onto the E-TEC engine--and some special difficult with the electrical connections--the E-TEC engine could be trimmed up or trimmed down with no lag, no noise, and no hesitation.

I will soon test the hydraulic trim-tilt system on a lake.

My takeaway from this experience: do not give up on repairing an outboard engine on your own. This replair could easily have cost $2,000 to have a marine technician do the work.

[jimh]

Q4: what is the best equipment to purchase to join the diagnostic club?

I am a MacOS Apple person.

Glen--I am a MacOS user beginning with the original 1984 Macintosh computer, and through many other devices along the way that used the Motorola 68000 CPU, then devices with the RISC PowerPC CPU, and finally devices with Intel CPU chips. Now I have three MacMini computers, one with Intel, one with an Apple M1, and one with an Apple M4 CPU. I will share my experience with trying to use the EV-Diagnostics software for the legacy E-TEC engines, which has a current Version 5.9 (if I recall correctly).

Many years ago, about c.2009 when I first bought my model year 2010 E-TEC 225-HP V6 engine, I had a very nice MacOS MacBook Pro laptop, using an Intel processor. I was able to use some emulation software to create a Windows partition. And at the same time, I was able to use a USB-to-RS232 serial port device that worked both with MacOS and with Windows in the emulation. The result was I could boot my MacOS laptop into the Window emulation and then run the EV-Diagnostic software (older versions) on the MacOS laptop with an Intel CPU chip. Then I moved to a newer laptop, and then another newer laptop. But that approach ended for me some time ago, due to several factors. The final end came when my newest MacOS laptop died due to a second motherboard failing.

ASIDE on Apple Motherboard Warranty
The first motherboard failure was fixed under warranty with a replacement motherboard, but the replacement motherboard contained the same flawed graphics chip as the original. The problem was over time and over repeated heating-cooling cycles, the actual substrates on the chip began to fail. It took several years. So eventually, when the laptop was about eight years old, the graphics chip failed again. This time I went after a solution with a lot of zeal. I found some really arcane threads that described how the boot-up sequence could be edited so that the graphics chip would be ignored, and instead of the fancy graphics chip, the system would revert to using the graphic output on the CPU chip, which would be slightly lower resolution and slower rendering. I got that working and managed to get about six months more use from the laptop, then something else died on the motherboard, and I could not fix it myself. So that ended my ownership of MacPro laptops. Also they became crazy expensive. I changed my portable Apple device to an iPad Pro, which I bought years and years ago and it is still working and very useful. Really my experience with Apple hardware has been flawless, except for that darn MacPro laptop with a flawed graphics chip, and the rather sneaking warranty replacement with the same problem that killed it four years later.

OK, back to EV-Diagnostics: since I did not have any MacOS laptop, I was blessed with a very good friend who was a seriouis Windows OS user who frequently upgraded his laptop computers. He was also an E-TEC owner. He took pity on me and gifted me one of his old laptop computers, something like one he stopped using three generations ago. But the laptop was still suitable for running EV-Diagnostics, and that is what I have been using for the last four or five years to get engine data from my E-TEC.

The laptop sits around for about a year between uses. I have to put it on a charger for a day to wake up the battery. Then it will boot up and I can run the diagnostic software.

Now if you are still reading, here is my suggestion for you: buy or borrow or beg an out-of-date Windows laptop, or even buy a new one if the price is ridiculously low, and run EV-Diagnostics under Windows OS on that laptop.

I don't have any experience with these modern Windows OS versions. I assume they will work with EV-Diagnostics.

The stumbling block for most people seems to be getting the USB-to-Serial device to have the right driver software and properly configure it as a Windows CommPort. The best USB-to-serial device is probably the StarTech devices, like the ICUSB2321F. See

https://www.startech.com/en-us/usb-seri ... liant=true

These StarTech devices are known to work correctly. They are about $45.

[glen1941]

Jim--thank you very much this great information. I started with the Apple Classic back in 1990, and have moved through various Macs to my present 15-inch Macbook Air, which I love.

Soon I will get started with assembling the gear needed to use EV-Diagnostics software. I will probably buy an older Windows laptop and one of the "kits" [of soft ware and USB-adaptors and cables] offered on-line. I'll manage to get it to work, and then learn how to read the data.

I tested the trim-tilt repair today, as well as the new high-pressure fuel pump.

I tied the boat to a dock and then advanced the engine throttle in forward to 4,000-RPM. This resulted in tearing out the mooring cleats on the boat gunwales.That will be an easy fix. The E-TEC engine is now running well.

The test of the trim system did not have a perfect outcome. The E-TEC engine can now trim up and down, but over time if the engine is tiled up to a high position it will drift down. I suspect that either the new manual release valve is not tight enough or a ram seal replacement will be necessary this Fall.

[jimh]

The tilt trim problem is resolved. The main cause of the failure was the faulty manual release valve.

From you long narrative of you actions in the repair, I believe you installed a new manual release valve twice. You indicate the first new manual release valve did not provide a remedy to the problem. Then the second manual release valve you installed eventually, after you restored fluid to the system and bled air from the system, did provide a remedy.

Q2: what was the difference between the first and second manual release valves that you used?

[glen1941]

Jim— you are correct, my narrative was not clear.

I installed the Five Star-brand manual release valve—they claim to have designed a much improved valve—while the trim-tilt assembly was still on the engine, and got no improvement.

I decided to remove the assembly [from the E-TEC] to better install the valve, to maybe see what else was happening, and to be able to get to the difficult-to-access fluid fill hole. With the trim assembly off of the E-TEC engine, I removed, cleaned and then reinstalled the Five Star manual release valve, rigged up the electric jumper cables, and then commenced the up-down hydraulic fluid] filling process, and that got the [trim actuator] ram to move up and down. This would have never happened with the [trim-tilt assembly still installed on the E-TEC engine on the boat transom] in boat.

The E-TEC engine is now trimming smoothly up and down, but it still leaks down slowly.

Tomorrow is a work day on the boat, and I will include torquing the valve down really tight. I only used a big flathead screwdriver to tighten it. The Five Star valve has a good sized lug for maybe a 3/8-inch socket. The specs [and forum] say torque to 55-lbs-feet to keep from leaking. I hope that works.

Also, for good measure, I will install a new [engine crankcase vacuum-operated air-motor] fuel lift pump.

[Moderator's note: in this post and throughout this thread, references to the E-TEC engine as a "motor" have been changed to "engine". This is done to reduce ambiguity when the author indicates certain other parts of the engine which contains a "motor" such as an electric motor that operates a fuel pressure pump. To avoid confusion between the entire outboard engine and a part of the outboard engine that has a motor, for many years now the practice used on the website and in this forum is to always refer to an outboard propulsion engine as "the engine" and never to refer to it as "a motor." Unless this distinction is maintained, readers can easily become confused when reading narratives about repair procedures.]

[glen1941]

Oh boy, I am glad that I re-read the torque specification for the manual release valve: the correct value is 55-inch-lbs, and not 55 feet-lbs.

[jimh]

Regarding buying a "kit" of components on-line to acquire the EV-Diagnostic software, a USB-to-RS232 serial adaptor, and the specialized cable to connect to the diagnostic port of the E-TEC engine EMM, I offer this advice: my preference is to NOT buy a cable that includes its own USB-to-RS-232 adaptor, and instead to get a cable that is just an assembly of connectors and wire, and then get the recommended name-brand StarTech USB-to-RS232 adaptor.

The reason for this is to be certain that you can get proper driver software for the USB device from the manufacturer. My thinking is that buying a cable with permanently attached USB-to-serial device often results in some unknown brand of actual chip in the assembly, with the result that finding the correct USB driver software for the particular version of WindowsOS that you might be using can be a big source of problems.

Also, having the USB-to-serial device and the cable as separate parts will allow you to diagnose problems with each component separately. For example, if there is a bad connection in the cable assembly you can easily find that by using an Ohmmeter. With an integrated cable-and-USB-convertor, you won't have much chance to figure out why it does not work if there is a problem.

[glen1941]

[On a recent on-water test, the 2018 E-TEC 90-HP] engine cranked well, and then it ran well, until it would occasionally surge. When this happened, the boat which seemed to be running well would leap into another gear faster for a moment. I hope this is only a fuel starvation problem.

I will replace the [fuel hose] primer bulb with a new OEM primer bulb. I will rebuild the low-pressure [fuel lift] pump.

I want to get started with the EV-Diagnostic software. I read your posts several times.

[A vendor using the identification] Powersports has a BRP OEM cable with software for about 150-E [presumably E is to be interpreted as the Euro].

Q5: would purchasing the above [i.e, the EV-Diagnostics software, and a proper cable to interface with the E-TEC engine, and some undescribed type of USB-to-serial adaptor] help me?

ASIDE
On Saturday, September 5, 2026, I took the boat to Keowee [apparently the name of a reservoir lake in South Carolina,]. The [weather that] day was great.

[jimh]

Q5: would purchasing the above [i.e, the EV-Diagnostics software, and a proper cable to interface with the E-TEC engine, and some undescribed type of USB-to-serial adaptor] help me?

I am not sure what area of "help" you are asking about.

It you plan to continue to work on your E-TEC engine yourself, then having the EV-Diagnostic software and being able to connect to your E=TEC engine, and being sufficiently familiar with the software to use it will certainly give you access to more information about the engine than you have without the EV-Diagnostic software.

The EV-Diagnostic software can perform many functions. But for an untrained person using the software, the typical uses are limited.

Please read my article at

EV-Diagnostics
https://continuouswave.com/forum/viewtopic.php?t=4706

There I mention the following typical uses for the software that an untrained user would be likely to access:

A typical E-TEC engine owner will use only a few functions in the software, such as:


• creating an Engine History Report
• setting the oil use rate
• calibrating the NMEA 2000 TRIM values
• enabling the water pressure sensor
• setting the INSTANCE of the EMM of the E-TEC if used with other E-TEC engines in a twin, triple, or quadruple rig.

The engine history report is a very useful collection of information about the engine. The E-TEC engine has an EMM which will observe and record various SERVICE CODES and the exact engine run time when they occur

In addition to the EV-Diagnostics software, you also need the SERVICE MANUAL for your specific E-TEC model and year engine. In the service manual there are details about all the service codes, what they mean, and what a typical action would be based on the service code. You can find PDF copies of the service manual for many E-TEC engines in an on-line archive maintained by a fellow in Australia.

[jimh]

I will replace the [fuel hose] primer bulb with a new OEM primer bulb. I will rebuild the low-pressure [fuel lift] pump.

For more about how the in-line primer bulb in the fuel system should be installed and how to use it as a diagnostic tool, read my article:

A Primer on Primers
https://continuouswave.com/whaler/reference/primer.html

Using an OEM primer bulb is a good plan. Some aftermarket primer bulbs don't work very well.

As for the fuel lift pump, it is a very simple design. About all that can go wrong with them is for the flexible diaphragm in the pump to decay from use of gasoline fuel with too much ethanol.

I recommend you begin participating the web forum ETECOWNERSGROUP.COM
That forum is specifically for owners of E-TEC engines who need help with diagnosis and repair of problems with their engine.

[glen1941]

jimh—I have read your latest post re: the EV diagnostic business. Thanks.

Not afraid [BSME Ga Tech, PE [GA]]. Will follow a Path Forward of getting the software and cable apparatus from PowerSports, and a good used Windows [uug] laptop; then plug into info adapter on motor.

Will purchase or download service manual.

Will then look around on laptop screen without doing anything.

Will, as you suggest, get involved with ETEC owners group.

May likely take the boat to a Platinum Evinrude shop and pay to have training.

The questions that I will likely have are:

Q6: why is the engine surging?

Q7: is a cylinder misfiring occasionally?

Q8: where do I buy the wizard hat?

Thanks, Glen

[jimh]

Once you have the EV-Diagnostic software installed and running, the HELP section contains excellent advice on using the software. This software is, in that regard, extraordinarily well written to help the user employ the software. Just be careful about what actions you take, as the software is powerful and can change fundamental stored parameters. It was not intended for the engine owner, but to be used by certified and trained mechanics and technicians.

[glen1941]

I have just concluded rebuilding and installing the low pressure lift pump and testing the existing primer bulb.

ASIDE: I advise setting up a laptop on rebuild table and watching Dangar Marine's step by excellent step video while rebuilding, and following along.

For whatever strange reason, the rebuild kit does NOT include the two small springs--why the hell not?

Do not lose the ones which came with the pump.

I found that the top, small spring had been compressed down onto its threads and would not move at all.

I have reinstalled pump. I have tested [the existing] primer bulb by installing clear hose on discharge side. Gasoline was raised about three feet, then only receded slightly.

I have reconnected a fuel line [from something] to [the engine].

With just a few pumps [on the existing primer bulb and the] bulb was hard.

The [ENGINE--PLEASE DO NOT REFER TO THE ENGINE AS "the motor"] started instantly.

CONCLUSION DEDUCED: Even though in an earlier test* I found adequate 6 to 8-PSI pressure, something was wrong with low-pressure lift pump.

Next test will be on a lake in a few days

-----
*--that earlier test was done when I could measure pressure at the high pressure pump test point when high-pressure pump was not working

[jimh]

ASIDE: When you want to inform readers that they should watch some youTube channel and a particular presentation on that channel, it would be much more beneficial in terms of giving advice and useful information to readers if you give the URL to the exact presentation on youTube you think is valuable to watch.

[glen1941]

Jim,
As usual, correct, will do. Back to the "surging" business. Took boat to Lake Hartwell for first time, and last time. Boat ran 4000rpm and 24mph and seemed to be going well; then it would "surge". The boat would jump to 5200rpms, then settle back to 4000. Everything in the fuel chain is new from and including tanks through VST. Not able to interrogate EMM at this time. Reading up on spark plugs and need to "index". Is this a next step of trial and error that I should take? I can do this. It is very possible that while every test was made on the motor before purchase, that the seller had not done the necessary on the plugs. Thanks, Glen

[jimh]

Very quick immediate changes in engine speed under load are often caused by electrical changes, like a cylinder suddenly having spark or losing spark. By model year/production year 2018 the E-TEC ignition system had changed to inductive discharge instead of capacitor discharge, which produced longer duration spark. A badly fouled spark plug could be involved, or a spark coils about to fail.

On my 2010 E-TEC there was never a misfire or a stumble, until while cruising in remote northern Lake Huron on the wilderness shore I heard the engine actually misfire. I thought it was due to bad fuel, as the fuel I was able to get up there was a bit sketchy, but on later investigation (and a SERVICE CODE hint in the engine history report) the trouble was due to a spark coil occasionally shorting to ground instead of through the spark plug.

The spark plug service life is usually many hundred hours—like 300 hours, at least.

[glen1941]

RECAP OF ENGINE SYMPTOMS for 2017 E-TEC 90 HP

The [engine] cranks well, runs well, then suddenly the engine speed increases for three to five seconds. Then the engine resumes to seemingly run well, but it might actually be running on only two of the three cylinders.

Next I will throw some time an money at the engine by installing new spark plugs and indexing them.

I do not want to buy three new spark coils at $100 each as an experiment.

Taking the engine to a shop will cost $125-per-hour for--I am sure will be--at least three hour.

If new spark plugs do not remedy the problem, I could buy one new spark coil and move it from cylinder to cylinder. to see if that would cure the problem.

In about three weeks I leave for a two week vacation. I do not want to start on the EV-Diagnostics software project until I return.

Q9: would EV-Diagnostics identify an electrical problem such as a fault in an ignition spark coil?

[jimh]

Q9: would EV-Diagnostics identify an electrical problem such as a fault in an ignition spark coil?

Yes.

Please read my article about how EV-Diagnostics pointed directly to a fault in an ignition spark coil. See

E-TEC Engine: Maintenance History After 17 Seasons
https://continuouswave.com/forum/viewto ... 937#p22187

My detailed narrative will be useful for you. I also show what spark plugs look like from an E-TEC after seven seasons and 265-hours of run time.