115 MERC fourstroke ISSUES

 Seeking some advice.

I have a westerberg with a 2016 115 CT model mercury fourstroke. It's done about 160 hrs. Always be serviced and the motor runs like a dream 99% of the time. It seems strange but sometimes on my way back in from a fishing or diving expedition where I've been cruising for about 30 mins at 20 knots i get to the river and have to cruise up the river for 10 mims doing 8 knots it randomly  skips a beat and the motor breaks down. On the way out it runs fine, and while I'm about and about no issue. Seems to only happen when ive been cruising up the river doing 8 knots for about 5 mins at around 2, 2.5 thousand revs after I've been out all day. Not sure if its related to the motor being hot after being used all day. 

I took it to the mechanic I thought it may have been spark plugs or fuel related. He went over all the fuel system, ran the computer, changed the spark plugs, filters checked everything and said he couldn' find an issue. Went to rotto and back, did the exact same things on the way back in, after 5 mins of cruising back up the river the motor revs just drop up and down, almost like I've hit something. If i drive faster and get the revs up it sound beautiful, but if i go down to around 2.5 thousand revs just under planing it would do it again. I've tried priming the fuel, making sure theres no water in the fuel filter. Spark plugs have been replaced. All fuel lines replaced.  I'm running out of ideas, can anyone help. 


Posts: 3930

Date Joined: 01/02/10

This isn’t an isolated issue.

Fri, 2019-10-11 09:58

This isn’t an isolated issue. Mate in Rockhampton has the same issue with his 150. No fault codes recorded and only does it when warm, generally on the way home after an offshore trip.

His next plan was to have a go pro set up to capture the issue to pursue warranty replacement from merc as they have already tried a fair few ‘fixes’. 

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Does anyone know where the love of god goes, when the waves turn the minutes to hours?

Mitch Westy's picture

Posts: 10

Date Joined: 16/07/19

 The problem is everytime I

Fri, 2019-10-11 12:05

 The problem is everytime I take it to the mechanic they charge. How many times has your mate taken it back in 

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Same same same issue. Gets

Fri, 2019-10-11 10:14

 Same same same issue. Gets us when trolling at 8-10knots 

runs like a dream at higher revs all day, but when trolling at lower revs after a period it jumps around like crazy.

taken it back to merc dealer heaps of times - replaced fuel lines etc etc etc. 

I've video'd it to prove it and no answer provided except it's must be my fault...

fukin over it. Especially given it runs like a dream in every other situation.

first merc I've had...last one I'll ever go near...old yammy had 3000 hours on it never an issue.

Mitch Westy's picture

Posts: 10

Date Joined: 16/07/19

Ohh shit

Fri, 2019-10-11 11:34

 I'm gonna take the Merc mechanic out on my boat and show him. If we rule out that it's not fuel or anything that I've done then it should be covered by Merc. 

gillyL's picture

Posts: 6177

Date Joined: 26/04/14

.

Fri, 2019-10-11 10:16

.

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lucky i love to fish because i cant catch any.

 

BM294

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Took the mechanic out in

Fri, 2019-10-11 12:13

 Took the mechanic out in fact I gave them the boat and they took it out too; saw the issue and still blamed the fuel lines! It ain't the fuel lines I am certain.

I am certain that it's just a piece of shit motor for low speed inc trolling all day

 

all that said, because I can't afford to buy a replacement motor I'd be really interested if you kept be informed if you find the issue/solution??

Mitch Westy's picture

Posts: 10

Date Joined: 16/07/19

 Will do mate. Really keen to

Fri, 2019-10-11 14:12

 Will do mate. Really keen to get it fixed 

Posts: 215

Date Joined: 06/02/14

Mine did the same

Fri, 2019-10-11 13:11

 Mine did the same, progressively got worse, new computer was required.

Mitch Westy's picture

Posts: 10

Date Joined: 16/07/19

Was it covered by warranty?

Fri, 2019-10-11 14:11

Was it covered by warranty? How would they know if the computers fucked if it doesn't show any faults 

Posts: 215

Date Joined: 06/02/14

NOt much

Sat, 2019-10-12 12:25

 Was out of warranty, and some of the mehcnaics now , say theres nothing wrong if no error codes raised, when there is.

 

Took 3 mechanics before the problem was found.

tot's picture

Posts: 926

Date Joined: 31/01/10

I have

Fri, 2019-10-11 15:17

An 09 60 4st and have had similar. I leave motor running while drifting as i dont drift far and every time I go to the top of the drift it is a little rough putting back up. If i punch it it is generally fine and yes on occasion when coming back into the marina and back down to 7 its rough. I'm going to take a portable tank and bypass all fuel lines and fitler and see how that goes. 

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Reverse cycle a/c supply and install

scubafish's picture

Posts: 662

Date Joined: 15/08/12

Just suggestion

Fri, 2019-10-11 15:36

Did the Mech check the SENSOR Map ?
Ask them what the sensor map does.
sounds like a fuel pump issue not got enough ummf in the pump at low revs.
But in the computer age they should be able to chuck it on the computer and wallah found the problem.
Unless they are full of shit and dont have a Diagnostic machine for Merc.

https://www.boats.net/catalog/mercury/outboard-by-hp/115hp/2b095049-up-cat-90-8m0087973-efi/integrated-air-fuel-module-components

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http://img.gg/w9G4y9P

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 I suggested the same thing

Fri, 2019-10-11 21:45

 I suggested the same thing re fuel pump not getting the job done at low revvs- they recon not. 
ive seen them plug a laptop into it - they reckon it showed nothing

 

Stevo81's picture

Posts: 1172

Date Joined: 16/04/12

 Have you searched or asked

Fri, 2019-10-11 19:01

 Have you searched or asked on The Hull Truth? Some very helpful mechanics on that forum 

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                                   ••••••••  Electrical Contractor NOR  ••••••••

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Search everything and came

Fri, 2019-10-11 20:42

 Search everything and came up with nothing....

sea-kem's picture

Posts: 11794

Date Joined: 30/11/09

 Far out mate I thought you'd

Sun, 2019-10-13 14:46

 Far out mate I thought you'd that issue sorted, could be one for dept of fair trade? 

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Love the West!

gillyL's picture

Posts: 6177

Date Joined: 26/04/14

 yup, get everyones details

Sun, 2019-10-13 16:44

 yup, get everyones details and start hassling mercury AUS. this doesnt seem like an isolated issue

 ive been out at sea when this happens and it makes you real uneasy pretty quick. feels like the motor is trying to jump of the transom

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lucky i love to fish because i cant catch any.

 

BM294

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Will do exactly that such a

Mon, 2019-10-14 12:37

 Will do exactly that 

such a fuk around but no cash to just replace it so unsure what else can do.

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Nope toxic issue and

Mon, 2019-10-14 12:39

 Nope 

toxic issue and complete denial so far

only so far dealt with dealer

next step merc australia cc fair trade ombudsman

 

still trying's picture

Posts: 292

Date Joined: 27/06/17

 Sounds like as a group you

Mon, 2019-10-14 13:15

 Sounds like as a group you would have a very good case hard to ignore. I liked the statement the salesman at a boatyard told me once, it's not like you can get out and push. 

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 rather be fishing

uncle's picture

Posts: 7946

Date Joined: 10/02/07

Consumer affairs

Mon, 2019-10-14 14:17

 Mate, susposed to be fit for purpose

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all aggressive fish love bigjohnsjigs

sea-kem's picture

Posts: 11794

Date Joined: 30/11/09

 Yep that's it Unc, even if 

Mon, 2019-10-14 14:31

 Yep that's it Unc, even if  out of warranty and relatively new they have to fix or replace if not fit for purpose. 

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Love the West!

Posts: 148

Date Joined: 20/07/05

I have a 2017 115 ct Pro

Sun, 2019-10-13 13:55

I have a 2017 115 ct Pro xs.

Did a run today, cruised for 30 minutes at 3600 rpm to 4000rpm, then dropped back to 8 knots for 10 minutes to see if any issue.

was glad to see no problems.

ive done 185 hrs and have zero issues to report, great motor Iam wrapped.

cheers 

bolts 

 

ChrisG's picture

Posts: 542

Date Joined: 30/12/11

 Issue kicks in after about

Mon, 2019-10-14 12:35

 Issue kicks in after about 45+  mins mate, sometimes an hour