Evinrude 30 outboard issue?

[rbcoomer]

Had to abandon the run out to see the Cowes-Torquay-Cowes racing today due to a strange outboard issue - I think....

We launched ok at Teignmouth (Manically busy there today) and pottered down to the estuary without issue, but when we went to open the throttle, she started to accelerate and then appeared to loose drive - suddenly as if something had snapped. (A notable loss of forward momentum) The engine revs picked up as usual but no power/drive. Instead there just seemed to be a lot of cavitation and foam in the water. I'd expect some extra 'froth' due to increased exhaust gases etc at higher revs, but this was in danger of creating a hole sufficient to swallow the stern! The boat is a 14' Fletcher and usually planes effortlessly - she has hydrofoils (fitted before I got her).

I initially thought we'd lost the prop, but as soon as I dropped the revs back to just above tick-over, she 'gripped' the water and plodded along as before. Prop is in situ, nothing entangled, turns freely by hand out of gear and turns about a third of a turn when in gear before meeting drive-train resistance - much as before.

Weight in the boat was similar to usual - 2 adults + an 8 year old and none of us are that 'large'. We were without the usual 'supplies' and kitchen sink as we weren't going out for that long. I have added some weight over the last 12 months in the form of a 2hp auxiliary which resides in the ski-hole in the bow and a 2nd fuel tank to the bow (portable tank not fixed). Both of these have been present on other trips, but then tanks perhaps not both full - today they were as we were planning to run up the coast to Budleigh Salterton/Sidmouth to watch the racing and then back to Torbay/Dartmouth in the afternoon, before returning to Teignmouth. (Extra tank needed for range) I think the last time both tanks were full, the 2nd was by rear seats not in the ski-hole up front however...

If not weight then I'm not sure where to start looking, as prop is in pretty good shape and no signs of damage or oil leaks etc. She made it back to the slipway without issue and before coming in, we did in fact head back out from the estuary for a couple more attempts, but with the same result. It didn't seem to matter if it was a slow speed build up or drop the hammer, it would 'bite' to about 6kts (just over hull speed) and then revs would rise rapidly but speed fall off. Can the effects described be caused by excess weight and would 2.5 people plus 50L fuel and an auxiliary outboard really exceed the 4 person capacity?

Is it possible there is some form of viscous coupling that's ok at low power, but slips under load? It feels almost like a clutch that's fading, but I didn't think outboards had a clutch...

I'm guessing that the issue is most likely one of weight and I need to run again without the bow tank to prove one way or the other, but wonder what advice the wisdom of the forum has to offer?

Many thanks,

Robin

 

[rafiki_]

On my props there is a rubber centre that is designed to reduce the impact shocks. These can slip when worn. Not sure about your outboard prop, but could there be something similar?

 

[rbcoomer]

Thanks Rafiki_, I wondered about something along those lines, but can't see anything in the parts drawings that looks likely which I why I started wondering about how a weight issue would be likely to manifest itself. Not so much too much, but perhaps too far forward? We tend to all sit on the forward facing seats too, due to the fumes from the 2-stroke in the back at river speeds.

The link below is my motor, but the only part that I think might fit the criteria is no.69, but thought the prop was direct on the shaft splines. I guess I need to pull apart and look or do a lightweight test run to prove... http://www.boats.net/parts/search/BRP/EVINRUDE/1988/E30ECCE/GEARCASE/parts.html

I've heard of instances where boats fail to plane, but not cavitation/prop slip like this.

There's a wheel bearing going on the trailer now too, so I need to do that first - a busy few days I think...

 

[rafiki_]

Sorry, I can't see the pictures on my iPad, just the parts breakdown. From a quick look through, I can't see anything that might slip. From your description, if the boat was struggling to get up on the plane, I think the engine revs would be an indication that the engine was struggling, and not reaching the normal revs. Could the prop have suffered some damage, and be spinning ok, but not producing enough thrust?

 

[rbcoomer]

Cheers,

Engine appeared to rev freely (if anything could even have been going to over-rev, but I cut back the throttle) and prop is ok - not immaculate, but no major damage more than 1mm at most.

 

[rafiki_]

I would give it a go in your normal trim, without all the extra load, and see what happens.

 

[VicS]

With very little doubt its a "spun hub". Classic symptoms.

Check by scribing a line across the end of the prop shaft and making a mark on the prop in line with it.

Go for a spin and power to the point where it starts to lose drive.

Check the marks. If they don't line up any more it confirms a spun hub.

But if the boat is now out of the water take our word for it and get the prop repaired. Part #69 is the offending bit. It is slipping inside the prop ( it's splined on the shaft)

Should have it all sorted by the time you have done the trailer wheel beraings

Try Willsmarine in Kingsbridge if you need an agent for Evinrudes

 

[rbcoomer]

Thanks for the help guys, I'll pull the prop etc off today if the rain ever lets up (a little damp down this end of the country today ). I need to go and get wheel bearings tomorrow so will ring Will Marine and see what they have in stock - they're only about 40 minutes drive. My only concern is that the prop is alloy and the parts diagram says 'obsolete' next to that version of part #69... I'm hoping there is an equivalent part?

The next dilemma will be whether to source locally or suffer the delay and import from the US. Wills quoted £80 for the last $20 part I needed and even with postage, duty and VAT it was under £40 from Boats.Net

 

[rbcoomer]

New prop?

It seems I can get a new prop from Steel Developments for £84, which I presume would slide directly onto the spline and thus include any equivalent bushing? If so, this would probably make more sense than trying to source an obsolete part!

We've not hit the original, so I can only presume that age must be a factor and that it was probably the original.

 

[Biggles109]

Robin,

I'm based in Teignmouth with an evinrude on a Shetland, will have to look out for you. Went down to Dartmouth yesterday, was followed by 3 dolphins off the Orestone, superb day.

Back on topic; I have bought parts from wills before, no problems. I use Birchell marine in torquay for service as they are closer and also evinrude agents, they might also be worth trying.

Brett

 

[rafiki_]

It seems I can get a new prop from Steel Developments for £84, which I presume would slide directly onto the spline and thus include any equivalent bushing? If so, this would probably make more sense than trying to source an obsolete part!

We've not hit the original, so I can only presume that age must be a factor and that it was probably the original.

Steel Devs are great suppliers. They will also source a new centre if you need one.

 

[rbcoomer]

Robin,

I'm based in Teignmouth with an evinrude on a Shetland, will have to look out for you. Went down to Dartmouth yesterday, was followed by 3 dolphins off the Orestone, superb day.

Back on topic; I have bought parts from wills before, no problems. I use Birchell marine in torquay for service as they are closer and also evinrude agents, they might also be worth trying.

Brett

Hi Brett,

Welcome to the forum! Apologies if I missed your post yesterday, I think there is a delay on first few posts - pending moderation! They tend to trust you after a few sane posts - not sure how I ever got past security...

Yes, I know Antony Birchell - he does excellent talks for us at SWFBR and I'll certainly be using him for future work! I think the part is obsolete however. Having now spoken to Steel Developments, I can get a refurbished prop for £42, a repair for £41 or a new 4-blade for £80 - all plus P&P & VAT. I think I'll go with a refurb 10x17 and get my existing 10x15 repaired. She doesn't lack acceleration but tops out around 19-20kts, so as we don't ski or tow toys, I think it's worth trying a higher pitch. I found a US site for calculating props based on engine, hull, weight etc and whilst the weight was a bit of a stab in the dark (1400lbs?), the suggestion was that with a 17 pitch prop, I could perhaps get as high as 25kts. I think that's optimistic, but 22-23kts would be good!

My Missus is very envious of the dolphins - we always seem to miss them! I've seen the seals a number of times, but she seems to miss them too. A shame as the wildlife and exploration was the main aim of the boat.

We will certainly look out for you - not been out much at all thus far this year due to weather and work, but hoping for a good autumn!

Regards,

Robin