The total cost of running an E-TEC has been one of Evinrude’s selling points from the very start. In this, the final installment of our E-TEC long-term review, we look at our operating costs over the 10+ years we’ve owned our 90 horsepower inline 3.

The original idea behind this project was to determine if the E-TEC did, in fact, live up to Evinrude’s marketing hype:

  • Fuel economy equal to 4-strokes
  • Better performance and more reliability than 4-strokes
  • Eco-impacts equal or better than 4-strokes
  • Reduced service costs compared to 4-strokes, due to longer-interval service schedules and new operating guidelines, such as no break-in period

Past posts covered performance and fuel economyreliability/durability/serviceability, and eco-impacts. This post compares the actual costs of running our E-TEC over a 10 year period to the hypothetical costs of running a similarly-sized 4-stroke. This includes the following:

  • Total costs of fuel and oil
  • Total costs of routine maintenance
  • Total costs of unexpected out-of warranty repairs that were not a result of carelessness or “user error”

Total Costs: Gas and Oil

Fuel Economy:

As mentioned in our first article, overall fuel economy was on-par with similarly sized 4-strokes, so gas costs were a push. With the E-TEC, we averaged roughly 4.5-5.0 mpg at cruising speed (20-22 MPH). That’s not bad for a 17.5′ skiff with a running weight over 3,100 lbs!

Oil Costs:Part of the total costs for our E-TEC: Evinrude XD-100 oil

When we first started using the E-TEC, we ran regular NMMA certified TC-W3 2-stroke oil at the recommended nominal 50:1 ratio. This is the out-of-the-box setting. Contrary to some early misinformation on the Internet, any certified TC-W3 oil will work, although Evinrude would probably rather have you buy their branded TC-W3 (XD-50). We mostly ran TC-W3 2-stroke oil from Chevron, since we could get it in bulk from our local Costco.

After two years of operation, we switched to Evinrude’s XD-100 oil, which allows the engine to run at a nominal 100:1 ratio. While the price for XD-100 is twice as much as regular TC-W3 oil, you use only half as much, so the net cost is the same, and you have to fill the oil tank half as often. As noted in our earlier posts, this has worked out just fine, with no noticeable issues, despite Internet predictions of engine burnout.

Comparison of Oil Costs, E-TEC versus 4-Strokes:

E-TEC:

Quarts of oil consumed over 10 years: 97
Average price/quart: TC-W3= $6.36
XD-100=$13.09
Average cost of oil /year: $127
Total cost of oil for 10 years: $1,270

4-stroke:

Average cost of oil change:
Filter: $18
5 quarts Marine-grade 10W-30: $38
Oil drain gasket: $1.75
Total cost /  oil change (no labor): $57.75
# of services requiring an oil change over 10 years: 11
Total oil change costs
over 10 years:
$635.25

Summary of Oil Costs:

The E-TEC was $ 635 more expensive over 10 years than a 4-stroke.

This obviously is heavily dependent on how much gas you burn, and under what kinds of loads. The more hours/year you run, the more 2-stroke oil you will burn, while the 4-stroke service schedule is a fixed cost every 200 hours, or once/year.

The total costs of operating an E-TEC includes regular service

Outboard service is not just wrenches and spark plugs anymore!

Total Costs – Routine Service:

For the E-TEC, we followed Evinrude’s recommendations – including no break-in, and service every 3 years, instead of annual maintenance.  For the 4-stroke, we followed the service schedule documented in the Owner’s Manual for one of the most popular brands in our area.

E-TEC:

Number of routine services: 3
Average cost / service: $510
Total Service Costs over 10 years: $1,530

4-stroke:

The table below is based on the average prices given during anonymous calls to two local dealers. The first two services are just inspections and oil changes, which I assumed I would do myself.  Since the subsequent annual services require more work (water pump replacement, valve adjustments, timing belt replacement, etc.), I left the oil changes in.

Service Event Cost
10 hour service (assume I do it): $0
50 hours (assume I do it): $0
Annual service
Avg. cost /routine  annual service: $501
# of routine  annual services: 10
Valve  adjustment at 3 years (routine service + this amt.): $150
Timing belt replacement at 5 & 10 years (routine service + this amt.): 2 x $300 = $600
Total routine scheduled  maintenance costs: $5,760

Summary of Total Costs for Routine Service:

The E-TEC routine service was $ 4,230 less than a 4-stroke over 10 years.

Of course, there are a lot of different ways you can reduce the cost of 4-stroke maintenance. You can do some or all of the work yourself, the most obvious things being the oil and lower unit fluid changes, with changing spark plugs following close behind. For the purposes of this comparison, we just assumed the dealer did it all.

E-TEC 90 Spark Plug at first service

E-TEC spark plug @ 100 hours

You could take a similar approach with the E-TEC, and it becomes even simpler, since there is no engine oil to change, no valves to adjust, and no timing belt to replace.

The difference in dealer service costs is primarily due to the change in service interval. The actual cost for an annual service was not that different between an E-TEC and a 4-stroke, however, the 4-stroke required 3 times more service in the same 10 year interval.

Comparison of Total Costs for Routine Service + Oil:

So…if you look at the total cost of both service and oil, the E-TEC was $ 3,595 less than a 4-stroke over 10 years, or about $360/year.

Again, your mileage may vary… As noted above, there are lots of things you can do to swing the numbers one way or the other.

Unanticipated Repairs:

EMM replacement:

As we discussed in our post on reliability/durability/serviceability, we suffered an EMM failure at the 4 year point. The problem cost us approximately $1,500 to fix, and was one of those things we couldn’t attribute to normal wear-and-tear.

Would this have happened on a different motor? Possibly. Addressed in later versions of the EMM? Also possible. Typically, you’d expect an EMM to last the life of the motor. In our case, the cause of the failure was never established. My personal theory is that it was damaged by the internal low voltage condition we experienced when we first got the motor (cause by a rusted fuel pump, which was caused by the installer not checking for water in the tank). Certainly can’t blame the motor for  that, but again, I don’t have any solid proof.

Leaking Oil Tank:

As reported in earlier posts, we developed a pinhole leak in the oil tank after the engine was out of warranty. The new tank cost $95, and we installed it ourselves. We’ll chalk this one up to a possible design or manufacturing flaw.

Blown head gasket:

This failure is not an uncommon one in outboards. Our previous motor also blew a head gasket at around 7 years of regular use, so we’re not going to count this in the cost comparison.

Broken Skegs:

Once every 3 -5 years I suffer major brain fade, and leave the motor down when I leave the house, or when I leave the local gas station after I fill up the tank. The end result is the skeg laying on the pavement. These were obvious user errors, and not counted in the cost comparison.

E-TEC 90 Broken Skeg

Ouch! Did this not once, but twice…

I also did this with Toy Boat 1, but on the old motor, the result was a bent skeg, not a broken one. I used to bend it out manually. It looks like the aluminum alloy in the E-Tec lower units is a bit more brittle than the old Johnsons.

In any event, I’ve found a company which will weld the skeg back on without removing the lower unit, which saves a bunch of money. Kudos to Propellers of San Diego for quality work.

Summary and Conclusions

Barring the unforeseen EMM and oil tank repairs, my E-TEC turned out to cost $3,595 less than a typical 4-stroke over 10 years (about $360/year). Even taking the EMM and oil tank replacements into account, the difference is still around $2,000, or $200/year. Closer to a push, but still leaning towards E-TEC.

Is that enough to sway your decision on a new engine? You can make your own decision…but I prefer the 3-year service interval and lower overall costs.

Would I buy another E-TEC? I’d say “Yes”! I’m sold on the E-TEC technology, and I certainly haven’t seen anything that suggests fundamental design flaws, or problems with the recommended service schedule or modes of operation (e.g. no break-in, running at 100:1 with XD-100 oil, etc.). If I were going to repower again today, I’d go with the 4-cylinder 115 or 90 HO instead of the 3-cylinder 90, but that’s a different story…