1992 Evinrude 40 HP VRO/Timing??

[wastewaterguru]

I have an Evinrude 40 VRO (1992) that was purchased this past spring and has about 100 hours on it for the year. Previous owner only used once per year for a summer trip and only put 8 hours per year on it......so I basically doubled the total hours on this motor just this year.

I was running at WOT about 32 mph on my 1983 Lund 16 foot boat on the Minnesota river. The motor suddenly started intermittantly losing 10 to 20% power and I immediately reduced to slow speed and putzed back to the ramp. The engine was acting funny even at lower speeds. It now idles at over 1500 rpm (used to be 700 or 800). It would still exceed the rpm limiter in the SLOW function so it wasn't from overheating or low oil..... the VRO system is still operating for this motor and I guess this could be suspect as well......but not sure its failure would get the experienced symptoms....

I took it to a shop for some basic testing. They performed a compression test which was 128 and 125 respectively. They did a leak down test as well which they indicated was well within specs. They did a spark gap test and that was fine. That was all they would do for the $75 I was willing to spend. Pretty good amount of testing for the money and I am not opposed to taking it back to them if I can't figure this out on my own.....or with help from you all.

I had a spare power pack from another motor and swapped that out with no effect.

I checked the electronic choke since it acted like it could be getting choked on one cylinder......this checked out fine. Pulled both lines to the top of the carbs and no fuel was leaking through to the hoses when operating.....but both spray fuel when the choke solenoid was activated.

I ran wire through all the jets and passages in both carbs and did not see anything that looked even slightly suspect in the carbs. This is the cleanest outboard I have ever worked on....

I am confused with the results of testing the timing. The timing for the #1 cylinder at idle with no load was already at 35 degrees and advanced off the scale as the throttle was opened. Manual says 19 degrees at 5000 rpm under load but I can't load test in the driveway. Do these numbers make sense to anyone. There is no way to adjust the mechanical linkage to adjust for this much timing advance to get it back on the scale.......

The timing being that far advanced explains the erratic behavior and the fast idle but I can't figure out a way to get it back on the scale.

Could the pick up magnet under the flywheel have suddenly shifted or come loose. I could not get the flywheel nut to come loose at 100 psi with an impact wrench rated for 300 ft-pounds. I will have to take it in for removal if needed. Was hoping for some words of wisdom.......

I use this motor 3 or 4 times a week and the lake sturgeon season on the St. Croix river is only open through October 15 so I am really eager to get this thing figured out.............

[Eric Wettschreck]

Dude, you are bringing back memories of mine.

Pull the flywheel, and check the woodruff key. Yeah, I know it's sounds silly, but this SAME EXACT THING HAPPENED TO ME.

The key sheared, and the flywheel turned about 30 degrees on the crankshaft. A new key, and voila, back in business.

Good luck.

[wastewaterguru]

Dude that would be awesome if that was the issue. I will see if I can borrow a slightly more industrial impact from someone at work. I think the better ones are rated at like 600 ft-lbs. No offence to DTRO but his wrench was a little wimpy. I guess beggers can't be choosers. I will update what I find. Any other thoughts?????

By the way Boilerguy.....I'll owe ya a 12 pack if all I need is the shaft key..

[wastewaterguru]

Gave this some thought and I don't think that's the answer. The T mark on the flywheel is at the timing arrow mark when the #1 cylinder is at TDC. If the flywheel moved, the initial mark would be shifted as well.....right??

[Surface Tension]

The worn key, even a minute change will throw the timing off.

Its worth a look and you'll have to take the flywheel off to get to the next steps anyway. A 92 should have UFI(under flywheel ignition). Although its possible that a 91 would have CD11 or UFI.

Something else to be looking at is synchronizing the carbs and ignition.

Whatever the case your going to need a manual.

No need for an impact wrench. Just use a breaker bar and strap the flywheel or don't strap the flywheel and give the bar a couple sharp raps with a hammer.

[boatfixer]

Flywheel key was the first thing that came to my mind as well. If that is not the problem, get a manual and start from scratch with the timing and synchronizing.

[DTro]

We tried the breaker bar hammer rap and it wouldn't budge. Frank when you say strap thy flywheel, how would you strap it?

And another important question. Is this flywheel reverse thread?

[Surface Tension]

A ratchet strap will work. Tie one end onto a bracket somewhere, route the strap around the flywheel and tighten and tie off back where you started. As you turn the flywheel it'll bite in and tighten. Leave the spark plugs in but remove the plug wire.

Pull on the breaker bar and then hit it with a hammer.

Righty tighty-lefty loosey.(counterclockwise)

[wastewaterguru]

I went through all the information in the manual and put all the carb settings (low speed mix) and mechanical linkage at factory recommended settings the first day after it happened to no effect. I am sure the mechanical linkage and timing advance mechanism are not the issue.....unless it's under the flywheel and not visible.

I need to get that flywheel off to eliminate the next round of possibilities anyway so that is the next priority. I do not have a strap wrench.

By the way it is the CD2 ignition...not the under-flywheel. I went through all the wiring harnesses and as I said have tried replacing the power pack to no avail. I could be off a year or two on the model year....seller told me it was a 1994, but I think it is a 93 or 92..........

I know that someone will want to know......so I'll get the serial/model numbers off it tonight and verify the year.

[Eric Wettschreck]

Is it the nut you can't get off, or the flywheel after you remove the nut??

If it's the flywheel, I modified my harmonic balancer puller to fit and it worked. If it's the nut either do as ST said and wrap a strap around the flywheel, and totally reef on the nut or hit it with a good impact and it should (should) come off.

[boatfixer]

Just use an impact wrench, you gotta know someone who has one.

[DTro]

Just use an impact wrench, you gotta know someone who has one.

350ft lbs doesn't do it

[steffanf]

Go back to using the breaker bar. However, go to the hardware store and get a 4-6 foot steel pipe that the breaker bar just fits into. Position the braker bar on the nut with the handle to your left, slide the pipe over it and push down. With that kind of leverage, you will definately get the nut off. Either that, or you will snap the breaker bar (although I never had this happen). Might want to use some penetrating oil on the bolt threads first... might make a little difference.

[boatfixer]

"at 100 psi with an impact wrench rated for 300 ft-pounds"

Oops, didnt catch that right away.

[Eric Wettschreck]

A little WD-40, or penetrating oil is needed.

I don't know how long you were trying, but don't be afraid to keep the impact on that nut for a while. I've had bolts and nuts that I had to hold an impact on them for upwards of 15 minutes to get them to break loose.

[Surface Tension]

Pull on it like it was a 2000 lb sturgeon.

Your going to need to pull the fly wheel too and I'm thinking that might be another hurdle, so maybe bring it to a shop and have them take the nut off and pull the flywheel.

[wastewaterguru]

I have the puller for the flywheel.....

I sprayed plenty of PB Blaster on the nut and exposed threads last week.

I am just too busy with the kids during the week this week with my wife out of town so may not get to play with it again until tomorrow or Friday.

Someone talked me into Sturgeon fishing tonight so that takes some time as well!!!

[DTro]

Someone talked me into... fishing

Now there's an oxymoron.

[Eric Wettschreck]

Heck, bring it down to my place. I'll get that puppy off, then we'll drink some PBR!!!!

[wastewaterguru]

How far from Prior Lake.....??

Don't tease me.

[Eric Wettschreck]

about 3 hours.

[wastewaterguru]

That may be a bit too far.......

I have acquired use of industrial tools for the evening. I should be able to update tomorrow with findings.......

[wastewaterguru]

Back in business!!!!!!!!!!!!!!!!

And I don't feel like an one-who-thinks-I-am-silly for thinking it was something under the flywheel......

Got the flywheel nut off with bigger impact wrench.

Pulled the flywheel with harmonic balancer puller and the impact wrench....and a blow torch to heat her up a tad.

Magnets on outside edge of flywheel for the stator were all fine. The round magnet that is all one piece that fits over the inside edge of the flywheel (timing magnet) was a tad loose. This magnet was not supposed to move. Marked its location and proceeded to force it back to where it looked like it belonged and reattached flywheel temporarily and check timing.......4 degrees advance.....Bingo. A little better than the 35 degrees that I got last weekend.

It had shifted a little at a time and explains why the darn thing kept running worse and worse as I was working to troubleshoot it.

Pulled the magnet off and cleaned up the mating surfaces and epoxied it in the correct position.

Rechecked compression......136 and 134

See ya'll on the water!!!

[Eric Wettschreck]

Good job dude.

Does this mean I don't get a box of beer???

[boatfixer]

Excellent! Good to hear you got it.