Siezed AGAIN!!

[mustang5]

Took the boat out for its first trip out of Gladstone, 220km round trip out to North West Island.

Made the rough trip out, 4 hrs later we were fishing Reds and Pearlies for the night. Came back this morning for a trip back and half way the Yamaha 200hp started hunting, like it was running out of fuel???? Stopped, checked all the lines, filters and everything... All seemed to check!!!!

Would then after stopping, for the next few Ks would act as per normal. But then the hunting would return on and off!!

Made it into Gladstone Harbour (Thankfully) for it to grind to a hault. Go to start and I get the dredded click!!! batteries fully charged so it seems as though its siezed.....

Any ideas on cause?? Or what "type" of sieze I am looking at????

piston to the block?? Bearing?? Conrod??

i know, probs best to wait until mechanic has a look!!!

But given this is only 80hrs since last rebuild, I think my faith in Yamaha's is finally done!!! Sick of boating in fear of this happening..

Oh wells, Thanks for reading :)

Good dinner tonight though :)

Thanks Gladstone VMR for the tow!

[Fed]

You got the click but is the starter motor spinning, is the bendix rising up & engaging the flywheel, can you turn the flywheel by hand, your batteries may or may not be good, are all your connections clean & tight?

[krazyfisher]

nothing worse and even when fixed it will take a long time to trust it again

[OPTI]

give the flywheel a grab by hand and see if theres any movement?

[Steeler]

If ya sure fuel supply is good and flywheel turns then i would be grabbing a compression gauge and checking if you have a cyl or two down on compression.

[wrenchman]

pull the spark plugs out and see if it turns over ,
its a bit like the question how long is a piece of string as to what your problem may be ,,

[mustang5]

Yeah I'll have a look in the morning.. Just died revving up to 4000 rpm when I finally reached smooth waters... Go figure eh lol

Boats. Money pits

[Vitamin Sea]

Yeah I'll have a look in the morning.. Just died revving up to 4000 rpm when I finally reached smooth waters... Go figure eh lol

Boats. Money pits

Feel for you mate, probably most on this site have been there before, I know I have.

Pull the plugs and have a look for metal (not good) if none there do a comp test, that will give you an idea of what's going on.

Doing those sort of distances you need 100% faith in the motor, I would be thinking very seriously about getting a new one if I were you, don't throw good money after bad buy rebuilding again.

my 2c

Bill

[mustang5]

Pulled the plugs, metal in top 2 plugs only. Flywheel turns about 4cm back and stops same spot each time I try to turn it.. Looks like the top carb has leaned out or something to do with the top crank bearing....

Plan at this stage is to figure out what went wrong, and go from there really.. What does a new 4 stroke cost these days?? Hehe.. Missus loves me at the moment.

[krazyfisher]

you should be able to get a 200hp 4/s for around $25-27k, a 200 efi 2/s merc is around $15k these are what I was quoted a couple of months ago

[murf]

Pulled the plugs, metal in top 2 plugs only. Flywheel turns about 4cm back and stops same spot each time I try to turn it.. Looks like the top carb has leaned out or something to do with the top crank bearing....

Plan at this stage is to figure out what went wrong, and go from there really.. What does a new 4 stroke cost these days?? Hehe.. Missus loves me at the moment.


Bugger :( thats gunna hurt no matter what way you go, hope it pans out for you in the long run

cheers Murf

[ozscott]

Does that mean it got .0005% leaner than an ETEC...:))))

Mate that is not good. I am sorry to hear about that. That is one thing that will kill a 2 stroke is really lean running.

Mate if it has 80 hours on since rebuild, what was the warranty on the re-build. If the same mechanic did the re-build and tuned the carbs and IF there was no fault in the carb or blockage afterwards that cant reasonably be ascribed to him, then I would be having a chat to him to see what can be done.

Cheers

[Steeler]

If ya half mechanically inclined pull it down and re-build it yourself, depending on how bad the top two linings are you may get away with honing it out and staying with standard size piston and ring kits.

Wurth make a great product that you spray into the cylinders to soften up any alloy prior to honing and at the very least you will learn a whole lot more about your motor and how it all operates.

[trymyluck]

Jeeze that sucks, I don't know if its still there or if its an option but there is a 06 200 4stroke yammie in the classifieds.

[Vitamin Sea]

you should be able to get a 200hp 4/s for around $25-27k, a 200 efi 2/s merc is around $15k these are what I was quoted a couple of months ago

Or a 200 Opti for 18.5K;) , lot of petrol in 7 ~ 10K

Trade it in mustangs, tell the missus how much money you will save with a new opti or whatever, don't miss on the safety factor either.

cheers

Bill

[mustang5]

So stripped her down, and top port piston (#1??) has broken at the pin. Doesnt look to be any damage to the bore other than metal shards everywhere...

Took the starboard side off and the top piston has hit the end of the head... But is still in tact to the crank..

The con rod seems tight to move.

Now what I want to know before I go too much further is, what could be the cause?? Given that it was running rough (on and off, hunting up and down with power) for about 100kms before this happened??

Cheers

[wrenchman]

are the old Pist`n broke and far from home ...lol

[BM]

So the no. 2 piston (top left) broke at the gudgeon and the no.1 piston hit the head but is still attached at the crank and the gudgeon. Correct??

[OPTI]

she detenated,the last thing that happens is the pin gets pulled out of the piston,it sounds like you picked up a piston 100 klms back and just kept driving it till it tore the pin out.
you will need a rebore on those top two cyclinders as they will be out of round now ,maybe a resleeve on one of them,two rods and maybe a crank [wont know till you pull her out]
kind of hard to tell what caused it by looking at those pistons as you have driven it for too long after the event ,its either run hot or lean :o

[mustang5]

So the no. 2 piston (top left) broke at the gudgeon and the no.1 piston hit the head but is still attached at the crank and the gudgeon. Correct??

That is correct mate. Same piston that went at last rebuild!!!!!!!!! In same fashion.

Now I felt heads when I changed spark plugs out there, they were cool to touch. It also has a temp alarm which I tested before going out..

With regards to oil, I know for a fact the oil setup was working and I also Pre-mix 100:1..

[FishHunter]

That is correct mate. Same piston that went at last rebuild!!!!!!!!! In same fashion.

Now I felt heads when I changed spark plugs out there, they were cool to touch. It also has a temp alarm which I tested before going out..

With regards to oil, I know for a fact the oil setup was working and I also Pre-mix 100:1..

As its happened to that same cylinder twice now I would say that cylinder is running lean either due a carb issue or a air leak.

2 strokes are very sensitive to mixture and it needs to be sorted or it will keep happening. What colour is the underneath of the piston crown? Your photo suggests it is black?
If it is black and ashy then it ran way too lean.

[BM]

Got any pics of the piston crowns? Are they eaten away (detonation).

Also, you indicated the bore is ok in the cylinder with the broken piston. So no scoring Aka grabbed a ring and trashed the cylinder walls?

[mustang5]

You can see the edges have been smashed, and so has the heads.. Worse so on the Piston still in tact.

Dont mind the screws, thats just how I tried to extract them.

I have taken a photo of the bore on the #2 cylinder which has a couple of lines which is the only notable damage I can see. These are very shallow.

[OPTI]

looking at the end pic ,looks like detonation on the exhaust side [lean] i would say ,the other side might of just been effected by schrapnel,yamahas run 2 to 3 thous clearance so pretty tight ,it doesnt take much.
id bet both cyclinders are out of round,resleeving is around 350 dollars rebore 50 ,but if your cranks gone,well the cost of the rebuild will start getting up there.

[mustang5]

Well, am I safe to say its a carbie issue on the top carbie if it has detonated??

I noticed the motor got a bit "louder" half way out there... Didnt think anything of it as it was still running fine at the time, but certainly would have something to do with it.

TBH, im amazed it lasted 100kms back looking at the damage!

[BM]

The piston still connected looks to be detonated. The other piston looks more like its picked up due to lack of oil/overheat, pulled a ring throuh the top of the piston, danced around the cylinder getting hammered into the piston crown and head and then spat out the exhaust.

Damage to higher cylinders usually steers one towards overheat being the main culprit but its not guaranteed.

The oil pump needs to be checked although its likely to be ok as its failure would be non discriminating in terms of failure location. Ie: oil pump failure will affect the oil flow to all cylinders making them all as likely as one another to go bang.

The oil check valves need checking as these can jam up ad cause an oil failure. Happened on my Yamaha jetski.

I'd also be looking closely at the waterpump and testing the warning system in particular the overhat sensors, although all this should have occured upon first rebuild.

Finally the carbs (top in particular) and the whole fuel system needs to be inspected.

[Vitamin Sea]

looking at the end pic ,looks like detonation on the exhaust side [lean] i would say ,the other side might of just been effected by schrapnel,yamahas run 2 to 3 thous clearance so pretty tight ,it doesnt take much.
id bet both cyclinders are out of round,resleeving is around 350 dollars rebore 50 ,but if your cranks gone,well the cost of the rebuild will start getting up there.


I spent about 4.5K rebuilding a 175 johnno fast strike, it then lasted about 320 hours.

Bloody outboards

Cheers

Bill

[Jarrah Jack]

I feel for you Mustang5....If I could intrude with a question from someone who knows SFA about these things.

What do the boys mean by detonation caused by running lean. Is it that there is not enough fuel oil mix getting to that cylinder so therefor it is not being lubricated enough causing failure. How would the gudgeon be forced out? could that be because the piston doesn't want to go up and down any more but is being forced to by the crank so something had to give way?

[Dignity]

Mustang5 I feeel for you having ben through some constant headaches with my motor. Just a question, how reliable is your fuel supplier, any chance that E10 is getting into your system as detonation has become far more prevalent since it's introduction. There is a servo near me that I swear has that sweeter smell than usual and I wont use it.

[mustang5]

Hey mate, I filled up with caltex 98 octane, all oil was also caltex. Tested the temp sensors before going out and always plenty of telltale. Felt the heads each time I pulled over to inspect and were always cool to touch.

I had a second outboard mechanic test oil delivery and all was good.

Anyone know a good place to take the block in Gladstone/rocky???

Looking at a full rebuild kit from the states, and a new crank when I find one.

[FishHunter]

I feel for you Mustang5....If I could intrude with a question from someone who knows SFA about these things.

What do the boys mean by detonation caused by running lean. Is it that there is not enough fuel oil mix getting to that cylinder so therefor it is not being lubricated enough causing failure. How would the gudgeon be forced out? could that be because the piston doesn't want to go up and down any more but is being forced to by the crank so something had to give way?

Detonation has nothing to do with oil quantity its what happens when the combustion temperatures are high enough that the end gasses spontaneously ignite before the main flame front from the spark plug reaches them. The two flame fronts collide and cause a "knock" these damage the piston and this in conjunction with the higher than normal combustion temperatures that result from lean running damage the piston crown and in extreme cases can pieces of the ring lands to break away and holes in the piston crown.





If you have ever heard a car engine knock at low rpm under load you have heard detonation, sometimes its a much lighter sound almost like sand being thrown under the bonnet but high speed detonation is inaudible without specialized equipment.

[dnej]

how old was the fuel you were using?

[mustang5]

400 liters straight into an empty tank and jerry cans the morning we left mate.

[OPTI]

with the dollar so good id definately be looking at a new powerhead from the usa,although you still need to find what caused the trouble in the firast place,pull that top carbie apart on a piece of clean newspaper and check the main jet.

[FishHunter]

I would be looking into another motor myself, my little brain would always be in "whats that noise?" mode everytime I ventured out.

[four_button_arnie]

Go have a chat to Steve Fleetwood, that's who I'd go to anyway.

Steve Fleetwood Marine
4972 9463


Josh

[Dignity]

Detonation has nothing to do with oil quantity its what happens when the combustion temperatures are high enough that the end gasses spontaneously ignite before the main flame front from the spark plug reaches them. The two flame fronts collide and cause a "knock" these damage the piston and this in conjunction with the higher than normal combustion temperatures that result from lean running damage the piston crown and in extreme cases can pieces of the ring lands to break away and holes in the piston crown.





If you have ever heard a car engine knock at low rpm under load you have heard detonation, sometimes its a much lighter sound almost like sand being thrown under the bonnet but high speed detonation is inaudible without specialized equipment.

or when octane is too low which means it actually burns too fast, higher octane actually burns slower but when it comes to E10 it is as Fishhunter mentions it burns hotter and several marine mechanics I have spoken to recently have confirmed their observation of what appears to be a significant increase of detonation in motors and quite a few of them are in newer motors.

[FishHunter]

or when octane is too low which means it actually burns too fast, higher octane actually burns slower but when it comes to E10 it is as Fishhunter mentions it burns hotter and several marine mechanics I have spoken to recently have confirmed their observation of what appears to be a significant increase of detonation in motors and quite a few of them are in newer motors.

Actually the alchohol burns cooler the reason it may cause detonation is the fact that in 100% alchohol you require 2.3 times as much alchohol as petrol to make the same power.
So adding alchohol to fuel actually leans the mixture out. On cars which have 02 sensors the ecu compensates, on motors without them which are tuned lean at cruise for emissions and consumption reasons it can be enough to push it into detonation.

[wrxhoon]

Have you checked the fuel pumps? If they not up to scratch and not supplying enough fuel that could be the cause of leaning out . You say she started hunting as if she was running out of fuel!!

V6 Yammies use to run 2 small fuel pumps, the 2 pumps run to their limit to supply enough fuel.. I don't know how old your is but pull the pumps out and have a good look at them.

If the engine is a bit old I would be looking at re-powring with a new DFI or 4 stroke .

[novice23]

been there and understand how you feel.
Can't agree with fish hunter more... if you lose confidence in your motor you'll also lose the enjoyment you get from boating. If that's you piss it off and get a new motor.

[mustang5]

Yeah I hear ya. Starting to look at pricing for a newie, and will see tomorrow what sort of trade in I could possibly get, if anything.

Best part is, as soon as I start winning over the missus after justifying the cost, our 1yo plasma decides to die.... Oh joy!!!!! Hehe

[trymyluck]

Honda have 5.99% interest at the moment.............:-X

[mustang5]

Tempting. Whats a new Vtec 200 Honda worth?

[Vitamin Sea]

Here's something else to think about, but a 175 upgrade to a L4:-X
http://www.kingswoodmarine.com.au/product137/detail/mercury-four-stroke-upgrade-2011/latest-mercury-deals/

[mustang5]

What's a good price for the 175?? I like these deals, adds credibility to my argument with the boss hehe cheers

[BM]

Have u stripped it down yet to see precisely what it actually needs?

No point writing it off prematurely but I certainly hear and understand the comments re loss of confidence.

Seems to me that the first rebuild potentially didn't address the original failure issues. If so, you have a case against the first repairer and hence, your rebuild costs could be covered by the original rebuilder if evidence is found to demonstrate that they failed to do their job properly.

It's not over yet mate, unless you fold..

[mustang5]

Haha I agree mate, the motor itself is not far from repair given the only dramas I can see is a fuel system overhall and a couple of pistons..

However, given my use, and my lack of confidence before this occurred, I think a new Outboard is well and truly called for, or at least something in newer nick...

A trip up here is at least 250ks round trip, however, when I was in Brissy, I never once doubted the 20 min trips to Moreton and so on. Just one of those things really.

Will get it repaired and sell her cheap :)

[Lucky 1]

Mustang, my heart feels for you. It would be hard to get this one past my missus(buying a new moter). Something I would do, but not without a lot of pain. Not a real expert in this field, but wouldn't the repair costs be close to, if not match the resale value of the ceased motor ?

[mustang5]

Resale on these motors in good nick is about 5k, based on private sales.

Been quoted $1200 for repair given the crank and bearings are all pretty much only 80 hrs old. Unfortunately items like carbs and wiring and pumps and so forth are all aged, and dont exactly match the new pistons and bearings (as it currently shows lol).

Will whack her together and keep it in the shed until sell time. Right now looking for a new outboard :)