Have i messed this up?

[Promc]

Evenin all,
Finally got round to getting a new engine for the 25(bought a F4.6 in the end)but ive got a horrible feeling i may have damaged it during the break in!

So far i have run 3 tanks of fuel through it for break in,the last of which i was able to open it out to full throttle.I had a little trouble starting it on tank 3,and lost maybe a third of the fuel during this time(pulling it through the engine).I finally got it going,warmed it up a little & started the process(slowly up to full throttle then off again).With about a 1/4 of the fuel left,the engine note changed from the boggy,new engine sound ,to something more like it should be.Not too long after that,the fuel ran out,but, me being me(own worst nightmare!:duh: )thought that as it was just starting to sound like it should,i should replace the fuel that i had lost at the begining to make it up to a whole tank through it whilst running properly.So i put another 1/4 of a tank in it & tried to turn it over,but it didnt fire so i left it to cool down.
Upon refilling the tank & trying to restart it for tank number 4,all i am able to do is pull the pullstart for 2 or 3 pops,then it stiffens up.
Ive removed the glow plug and pulled the pullstart without it,& I'm still getting fuel popping up through it,but once the plug is in,again, i only get 2 or 3 pops before it stiffens up.
The only thing i did notice,is that my fuel primer bubble is leaking slightly,i don't know if this will make a difference or not.
Any body got any ideas as to why this has happend/how to resolve it?.If its because ive been an impatient noob,please feel free to tell me 🙂.
Fingers crossed!.

 

[Double-O-Zilch]

Glow plug is bad. When you break a engine in it runs rich and will eventually kill the glow plug. Replace it and your primer and give it another go.

 

[zud00]

Try to start it with the glow plug a bit loose but then remember to tighten it back up once it is running. That works for me when it gets tough to pull.

But like parker said, check your glowplug.

 

[MotoPsycho]

Without witnessing, it is hard to guess.

Here is my .02.......

It sounds as though it is too rich. The fact that it started sounding "better" with a nearly empty tank lends itself to the "half tank lean issue" (something the f4.6 can be VERY sensitive to)

When it started running low on fuel, it was actually getting lean enough to run properly. When you refilled the tank above half, it went back to fat (too rich). This would explain the "tightness" as you crank - the onset of hydrolock.

Try leaning the HSN about 3/4 of a turn and see what it does. Then tune it back to a "somewhat rich" mixture, and continue break-in.

As was said above, verify proper glow plug operation as well.

-Moto

 

[Promc]

Thanks for the advice peeps 🙂.
I managed to get it going in the end (doesnt appear to be any engine damage...hopefully!).I started by replacing the plug,it still locked up on turnover,so i undone the plug & had a look inside the chamber.When i pulled the pullstart to see if it was still getting fuel,i noticed,on the first part of the pull,the top of the piston looked dry & what i can only describe as vapour(?) coming out of the hole.It wasnt rising like smoke or steam,but as the piston moved up,it came out of the top of the engine & evaporated.When i saw this i had an idea.
I remembered(don't know why) that when i was at school somebody showed me that if you close your mouth &, with your mouth still closed, push your breath into your cheeks & keep pushing,eventually,if you breath out slowly,you will see steam(sounds a bit weird,but it does work!).
So i removed the bubble,re fitted the plug,tried it again & it turned over straight away,so i finished the running in(wow,what a beastie! 🙂).
My conclusion(this may be way wrong,i don't know a huge ammount about engines,so i am only guessing!,can anybody verify if this happens?) is that because the bubble was leaking,instead of just fuel going into the engine,air was being pumped in through the fuel line.This air was entering the piston chamber ,being pushed up to the top of the chamber,compressed on top of the piston(the vapour that was seen),and this is why it locked up,because it couldnt be compressed any more.As i said ,this is only my opinion.
Whatever the problem was,the main thing is.......IT RUNS !!! 🙂
Again,thanks all.