96 50hp johnson problem

[tyrion]

hi guys i need help with my motor. A few hours into my first trip after having a new CDI, Coil,leads and plugs fitted she started to loose power. By the time i got back to the ramp it wouldnt plane only reving to 3000 rpm and would not idle. Although it was still running smooth out on the water when i got it home to flush it with muffs it would cough consistantly every 1 sec and agian would only run with high idle full on.

If anyone can help me it would be appreciated.

Thanx Tyrion

[kriso]

sounds like a miss fire

[tyrion]

what would cause a miss fire? timer base?

[kriso]

miss fires are ignition break downs, are you sure the plugs that where put in it the suggested for that engine? did check to see if the number on the original plugs are the same as the new plugs? ( if made by same manufacturer) good of been supplied a dodgy lead. why did you replace the CDi module

[tyrion]

the plugs are excactly the same i thought the same thing so i put the old plugs back in that night on the way back in i kept them in the boat for a just in case situation and it made no difference.

The CDI: I started the motor at home before heading out it ran perf then we got to the ramp, nothing at all no spark so i took it to yatala outboards they tested it and said it was stuffed they couldn't raise a spark.

[faulked]

check the plugs for oiling up sometimes if the fuel is to rich with oil they can gum up and become painfull

[kriso]

could be a timing issue but its something with out looking at it i couldnt diagnose over the phone. how old is the fuel as well could be bad fuel or water in the fuel it will present same symptons. i suggest a mechanic look at it

[tyrion]

my old man thought it was water in fuel to so today i emptied the tank and not one drop the boat is always garaged out of the elements.

You wouldnt know a good (reasonably priced) marine machanic would you :laugh:

ill check the plugs now faulked

Thanx tyrion

The fuel at the time was from the servo that arve now is about 3 weeks old

[kriso]

okay. unleaded fuel starts to go off after 2 week. also dont run the ethanol blend either in boats. if the plgs are fouled good be fuel or timing issues, depending where you live i have a mate that owns water tourqe marine at yatala just down the road from the pie shop.

[Feral]

I reckon its dirty fuel, put a fuel filter in line, you might need to clean out the carby's, it is probably a little bit of crap caught in a main jet.

[kriso]

if ya can take a photo of the plug surface so i can see the burn on it.

[tyrion]

this is spark #1 straight out of motor [img size=500]http://www.australianfishing.com.au/media/kunena/attachments/legacy/images/IMG_0503.JPG

[tyrion]

same plug [img size=500]http://www.australianfishing.com.au/media/kunena/attachments/legacy/images/IMG_0504.JPG

[tyrion]

and again [img size=500]http://www.australianfishing.com.au/media/kunena/attachments/legacy/images/IMG_0505.JPG

[tyrion]

i live in logan so yatala isnt to far away

[blockah]

i would be checking power to the coil first off for a bad conection. if you have been moving the wires around the coil one could of been a bit britle & cracked & be arcing out on some thing. that is the area i would be looking at first.:dry:

[goldnugget]

If its all new check for arching, could be a dodgy cdi unit, get the guys who fit it to check it. As far as blended fuels, all standard 'unleaded' supplied by BP is now blended 10% ethanol its in small print under the unleaded sticker on each pump. I did notice that 7 Eleven has stickers on their pumps saying they do not add ethanol, I asked then who their supplier was, cant remember who it was but it wasnt BP. Sorry to jump the thread a bit, just wanted to bring it to your attention.

[Master Sardines]

my two bobs worth... maybe sucking air through a hair line crack in the fuel line

[kriso]

the reason ethanol fuel shouldnt be used in 2 strokes is due to it burning hotter so oil- fuel ratio should be adjusted to accomodate. mate i should of asked for a pic of the gap too. if these are the new plugs fitted i would definatley say a problem also a shot of each plug from each cylinder will help pinpoint the problem. looking at the build up of the plug maybe fuel dramas or worst compression as the build shows results of a slow burn rather than flash igition wich is a fast ignition rate just short of a detonation (explotion is not good). could be as simple as left over gunk in fuel system coming through. but engine is definatley out of tune looking like that.

[kriso]

if you wanna take your boat there, ask for Trent and tell him fatty that you went to school with put you on to him. Or if Bj is there just say fatty trents mate and they will look after you. i think the labour is fairly priced and you just have to see the boats they build to know there quality is exceptional and well worth the price. they build boats from scratch for the racing ski lice and build there race engines too. also do the engineering (machining) for alot of the boat shops too.

[tyrion]

spark 1 [img size=500]http://www.australianfishing.com.au/media/kunena/attachments/legacy/images/IMG_0514.JPG

[tyrion]

and 2 [img size=500]http://www.australianfishing.com.au/media/kunena/attachments/legacy/images/IMG_0510.JPG

[tyrion]

spark 2 is nice and clean compared to 1 this is starting to look expensive:dry:

[reef_raider]

sounds like what happened to use with our motor earlier in the year, turned out it was only working on two cylinders instead of three

[kriso]

yeah mate as you can see definate issues there. i suggest you take to a mechanic to run some tests

[rumrunner]

i can do a few tests for ya and sort her out! if ya want?

im a qualified motor mechanic and ran my own shop in underwood for 7yrs!

i now work from home at browns plains while looking after my boy!

i will only charge $45 phr for afo members!

up to you ?

the offer is there !

Ian

[tyrion]

done deal rumrunner pm me your details please

Thanx tyrion

[tyrion]

UPDATE

Yeasterday i checked for water and gunk in the carbies all i could find was one drop of water in the bottom carb so i clean them both and blew the jets out with compressed air just in case this was the problem clean the sparkies up and tested the spark by eye excelent spark on both plugs. Started her up today only to find nothing had changed, it would only run smooth at high idle as i dropped the revs to around 1500 it would start to cough till it stalled.

I agree with those of you who are saying its a timing issue but with only limited outboard knowledge im clueless as to where to start all i can do is piss in the wind.

Thanx tyrion

[tyrion]

well problem solved thanx to Rummie turned out to be the timing magnet??(Rumrunner can clarify)under the flywheel had broken of therefore the timing was 6deg after TDC(I think once again rummie can clarify) he also done a comp test for me and she was running 155 on both Gotta be happy with that.

Thanx again Rumrunner and it was nice to meet you and the family, youve got a future customer here like i said ill have to do the impeller soon so keep a vacant space in your drive way. let us know when your heading out next and ill see if i can get out to that way if something breaks again you can tow me back in lol