30hp 2-Stroke Evinrude advice

[rbcoomer]

Hi All,

As a boating newbie, I'm hoping someone might be able to shed some light on a small running issue I have?

I brought first boat last year and had engine serviced locally before I used as boat had been stood a long while unused. They replaced impeller, oils, plugs and cleaned up the shaft which was very rusted. On my first outing the engine failed to restart and a friend towed me back in. Having recharged the battery, I diagnosed that there was no charge from the engine so ordered a replacement rectifier pack. The next trip out was on a local river and apart from a tendency to stall it restarted and ran ok. Third trip it stalled and wouldn't start - another tow in! I didn't use again last year as I wanted to sort various issues as funds allowed before going out again.

Over the winter I have replaced the diaphragm in pump (was very deformed and small seepage in seal), cleaned all the wiring and re-terminated battery leads. I've just replaced battery with a biggish 100aH marine unit and also concluded that the kill cord switch was a bit sensitive.

I now have the engine running fairly well and although a little 'lumpy' it idles much better than before (it was stalling after 20-30 seconds). I've also (on suggestion of a friend) given a good dose of Carb cleaner, which seems to have helped too.

The engine now starts 'on the button' revs up ok and pumps water, but still has a tendency to stall when dropping off the revs (it splutters most at this point). I'd really like to fix this a.s.a.p as I have a Rally on Easter Saturday which is in coastal waters! As we are looking at the possibility of 8knt easterlies, I really don't want to get stuck broadside restarting engine in a 14' boat with a 3' swell any more than I have to!

Any suggestions/diagnosis/pointers gratefully received.

 

[Lakesailor]

This site, iboats.com is a fantastic resource. I fixed a problem similar to yours on a 70hp Evinrude with advice from there.


Have you determined if it is electrical or fuel?

Does your motor have VOI (oil injection)?
I removed mine and used pre-mix which helped the low speed running enormously.

Are the plugs Champion?
Don't believe them when you are told that NGK etc have equivalents. Johnson/Evinrude worked with Champion to design their ignition system and the Champion plugs really do run better. (Vic will tell you the details).

There isn't any better way to clean the carbs than to remove and strip, cleaning with carb cleaner and using an air-line to get out any sludge stuck in the passages.

There is nothing worse than a motor you don't have confidence in.

 

[rbcoomer]

Thanks for the prompt response.

The plugs they fitted last summer are NGK Both plugs appear to be sparking ok if I turn over with them out.

The fuel is premixed - it has been in the tank over the winter, but ran 'lumpy' last year too when it was fresh. I have obviously cleared some other issues since then, so new fuel might help I guess and I'm sure the strimmer or chainsaw won't mind the marine oil!

I was going to strip down the carb, but a friend advised against on the basis that it is running 95% of the time and if I need parts, it won't be running at all for the rally. (That would be a bit embarrassing as I jointly organised it! ) It was his idea to blast a few times with the Carb cleaner which I have done.

I'll decant the fuel and mix up some fresh and see what effect that has, and ring around and see if I can source some champion plugs and perhaps new leads.

Cheers.

 

[Lakesailor]

Get the correct Champion plugs. NGK are not right.
It's to do with the resistance effecting the capacitive discharge ignition.
Champion plugs are designed to work with the Johnson/Evinrude ignition.

The fact the plugs spark when not under compression is not a clear indicator of their health.

 

[propnut]

I agree ,you should be using Champion plugs
New fuel will make a big difference,after a few months this unleaded stuff looses its get up and go !
Carb cleaner is great for removing old grot that forms in the carb bowls and immsulion tubes,but only works when you give them a good soaking ,followed by a blow out with a good blast of compressed air.I have found that squirting down the ventury makes little diffrence
hope that helps

 

[rbcoomer]

Thanks guys. I rang the nearest Evinrude service centre this afternoon to see if they stocked plugs and leads. Yes to plugs, but they supply NGK (!) and no to leads, they order in from the US. Thus I'm going to order new bits myself direct from iBoats so getting the right plugs and also new HT coils, but for the rally this weekend I'm going to have to 'wing it'!

I've found a can to decant the contents of the tank into and will mix up fresh juice tomorrow. I'll then take it for a run on the river and give another blast of carb cleaner. I will strip and clean the carb after the rally, before I use the boat again. It seems if I ease the throttle off slowly, there is much less tendency to stall.

Thanks again for the input.

 

[Lakesailor]

You are joking.
One of the best Johnson/Evinrude agents in the UK is Wills Marine in Kingsbridge, Devon. 22 miles away.

Even if you can't drive there they'll post stuff next day.

If you are saying they don't do Champion now. I am very disappointed.

 

[Palarran]

Have you checked the manual for the correct oil to gas mixture ratio? I have a Yamaha 30hp 2-stroke that ran like ****. I changed the plugs several times and it would take off and run great for an hour then back to the same sputtering when at low rpm's.

It turns out that Yamaha's (at least mine) run on 100 to 1 gas mix ratio. I was doing 50 to 1 plus some, just in case. After I leaned out the gas mixture, it ran great.

 

[rbcoomer]

You are joking.
One of the best Johnson/Evinrude agents in the UK is Wills Marine in Kingsbridge, Devon. 22 miles away.

Even if you can't drive there they'll post stuff next day.

If you are saying they don't do Champion now. I am very disappointed.

It wasn't them. I did ring them first, but was told the engineer wasn't in yesterday, call back today. I was surprised as I only asked for leads and plugs, but will ring back today and collect if they have them.

 

[rbcoomer]

Have you checked the manual for the correct oil to gas mixture ratio? I have a Yamaha 30hp 2-stroke that ran like ****. I changed the plugs several times and it would take off and run great for an hour then back to the same sputtering when at low rpm's.

It turns out that Yamaha's (at least mine) run on 100 to 1 gas mix ratio. I was doing 50 to 1 plus some, just in case. After I leaned out the gas mixture, it ran great.

That's interesting because the guys who serviced it for me said I could run anywhere between 50:1 and 100:1. Everywhere I've read says 50:1 so that's what I've been doing (fairly accurately I think as tank is 25L which makes it quite simple). If however they tuned up at 100:1 then I guess that could make all the difference? I lost a bit of confidence in them because they missed that fact it wasn't charging and never reply to messages, but perhaps I'm being unfair.

I've booked it in with a guy in Shaldon who comes highly recommended, but he can't do until next week - after the rally!

 

[VicS]

Regarding plugs

OMC recommend only Champion plugs

You don't identify the model ( year and model number) but the plugs recommended will almost certainly begin with the letter "Q". This indicates inductive suppression. They are special plugs for OMC CD ignition systems.
Plugs with resistive suppression will not perform well with the OMC ignition system

If you have NGK plugs with a "R" in the number that could well be causing you trouble because the "R" indicates that they are resistor plugs.

It is sometimes possible to find a suitable NGK plug. Inductive ones have a "Z" in the number. It is also possible to use unsuppressed plugs ( Except with VRO or OMS engines)

Post the year, preferably the model number, and i can look up the latest recommended Champion plugs for the engine and also tell you if there is an equivalent NGK plug that could be used.

Willsmarine will sort you out i am sure.


Re the fuel mix

For a few years from 1985 OMC specified 100:1 fuel mix . Following may failures and claims this was changed to 50:1.
All OMC engines using premixed fuel from 1968 onwards run on 50:1. None should be run on 100:1, even if the manual or decals say 100:1

iBoats

I second LS's suggestion /recommendations regrading the iBoats forums. The forums at MarineEngine.com are also pretty good

 

[rbcoomer]

Regarding plugs

OMC recommend only Champion plugs

You don't identify the model ( year and model number) but the plugs recommended will almost certainly begin with the letter "Q". This indicates inductive suppression. They are special plugs for OMC CD ignition systems.
Plugs with resistive suppression will not perform well with the OMC ignition system

If you have NGK plugs with a "R" in the number that could well be causing you trouble because the "R" indicates that they are resistor plugs.

It is sometimes possible to find a suitable NGK plug. Inductive ones have a "Z" in the number. It is also possible to use unsuppressed plugs ( Except with VRO or OMS engines)

Post the year, preferably the model number, and i can look up the latest recommended Champion plugs for the engine and also tell you if there is an equivalent NGK plug that could be used.

Willsmarine will sort you out i am sure.


Re the fuel mix

For a few years from 1985 OMC specified 100:1 fuel mix . Following may failures and claims this was changed to 50:1.
All OMC engines using premixed fuel from 1968 onwards run on 50:1. None should be run on 100:1, even if the manual or decals say 100:1

iBoats

I second LS's suggestion /recommendations regrading the iBoats forums. The forums at MarineEngine.com are also pretty good

Thanks for the detailed response - I've got to call Wills Marine again in the morning - engineer was out so they took a message and were going to call back regarding stock of leads/champion plugs but didn't.

I've got to launch a friend's boat early tomorrow at Brixham, but will head down to Wills thereafter for when they open. I've got new fuel, but was too late to start tonight - didn't want to rile the neighbours!!

My engine's hard to identify for certain as someone painted it to match the boat eek, but from extensive study of images and exploded diagrams leads me to think its an E30ELxxE - I've seen another one that appears identical and that's a 1988 - E30ELCCE. I think the plugs I need are QL82C? The engine has the Mallory ignition coils.

 

[longjohnsilver]

I've got an Evinrude on my Boston Whaler, Wills are the people to supply the correct bits, if no joy there try Ash marine in Topsham, they may be able to help.
Weather's looking good for your rally, could be a bit choppy tomorrow but the rest of the W/E should be fine. Might even bump into you on Monday, we're giving our RIB it's first run out of Exmouth so may well head Babbacombe way. What's your boat called? Look out for us in Lucky B!

 

[rbcoomer]

I've got an Evinrude on my Boston Whaler, Wills are the people to supply the correct bits, if no joy there try Ash marine in Topsham, they may be able to help.
Weather's looking good for your rally, could be a bit choppy tomorrow but the rest of the W/E should be fine. Might even bump into you on Monday, we're giving our RIB it's first run out of Exmouth so may well head Babbacombe way. What's your boat called? Look out for us in Lucky B!

Thanks John I will indeed look out for you. Our boat's "Charlie" - quite small @ 14' so don't forget your binoculars

 

[VicS]

Thanks for the detailed response - I've got to call Wills Marine again in the morning - engineer was out so they took a message and were going to call back regarding stock of leads/champion plugs but didn't.

I've got to launch a friend's boat early tomorrow at Brixham, but will head down to Wills thereafter for when they open. I've got new fuel, but was too late to start tonight - didn't want to rile the neighbours!!

My engine's hard to identify for certain as someone painted it to match the boat eek, but from extensive study of images and exploded diagrams leads me to think its an E30ELxxE - I've seen another one that appears identical and that's a 1988 - E30ELCCE. I think the plugs I need are QL82C? The engine has the Mallory ignition coils.

If its any where from1978 to 2001 the plugs should be :

20, 25, 28, 30hp; 1978 - 2001; QL77JC4 or L78V or QL82C; gapped at 0.030"

First choice is QL77JC4, L78V are surface gapped plugs, QL82C are the alternative conventional plugs. A little hotter than the QL77JC4

NGK BZ7HS-10 are the equivalent of QL77JC4 and should be quite satisfactory. (-10 indicates that they are supplied gapped at 1.0mm)

BTW you may be able to find the model number also stamped on a core plug on the engine.

 

[rbcoomer]

If its any where from1978 to 2001 the plugs should be :

20, 25, 28, 30hp; 1978 - 2001; QL77JC4 or L78V or QL82C; gapped at 0.030"

First choice is QL77JC4, L78V are surface gapped plugs, QL82C are the alternative conventional plugs. A little hotter than the QL77JC4

NGK BZ7HS-10 are the equivalent of QL77JC4 and should be quite satisfactory. (-10 indicates that they are supplied gapped at 1.0mm)

BTW you may be able to find the model number also stamped on a core plug on the engine.

Thanks Vic, I went down to Wills on the basis that I kept getting told to ring back tomorrow! They had the QL82C so I got those. The lass on the desk couldn't answer if they had HT leads, but thought they made them up and there was no-one to do, so I'll order a pair next week. The plugs in there were NGK BR6HS and were gapped at 0.065" (or very close to)!

Initially I couldn't start at all with the correct plugs/gaps, but as the ones that game out were black & sooty, I've leaned the mixture right up and she starts and runs now. Still stalls when cutting back the throttle, but idle is better - although still a bit of a mis-fire. This is probably mixture, but having run backwards and forwards between starter & engine at least 60 times in the last hour I needed caffeine and the battery needed a rest! If I can get a reasonable mix, I think she'll run well enough for tomorrow. I've booked it in with Mariners Weigh at Shaldon for 27th so we'll see what he makes of it! I think I'll order a new HT coil direct from the States Tuesday with leads and then I can swap each out in turn and see if there's any improvement in the mis-fire. It makes a sort of hiss and a puff of oil smoke then shudders to a stop - as if spark was lost perhaps? This happens most on deceleration.

Thanks for all the advice - kept me from despair and hopefully I won't now need a tow in tomorrow!

 

[VicS]

You are probably well rid of those resistor plugs.

Surprised you could not get the QL77JC4 plugs. They are probaby the most widely used in OMC engines

Check its firing equally on both cylinders ( by disconnecting one plug at a time). If its not then swapping bits around ( at least leads and coils) may help to locate the problem.

Instructions for initial setting and adjusting the carb HERE but its best to clean it first.

 

[Lakesailor]

I made a starter button connected between the battery and the starter solenoid (just the switching circuit, not the power leads). Means you can start the motor at the motor.

You can also make a spark tester to measure the air bridge the discharge manages. The spec is surprisingly wide.

 

[rbcoomer]

You are probably well rid of those resistor plugs.

Surprised you could not get the QL77JC4 plugs. They are probaby the most widely used in OMC engines

Check its firing equally on both cylinders ( by disconnecting one plug at a time). If its not then swapping bits around ( at least leads and coils) may help to locate the problem.

Instructions for initial setting and adjusting the carb HERE but its best to clean it first.

In all fairness, I probably could have got the QL77JC4 plugs, but left to drop friends boat in and head for Wills Marine before I read your message (was in Kingsbridge when you posted). The lass there didn't really know and there was no engineer available so I only had the part listed on the printout of the iBoats page to go on. I may revisit plugs when other issues have been sorted, but at least I know they are a suitable part now! Early start tomorrow for rally, so I'll post back on how it runs with new plugs. This afternoons meddling seems to have found the best setup at this time...

 

[rbcoomer]

I made a starter button connected between the battery and the starter solenoid (just the switching circuit, not the power leads). Means you can start the motor at the motor.

What a great idea - cheers!