285 - I give up!

[Trainsernie]

Well, I've been working on my 285 for a month now, and I'm ready to set fire to it - and it's not insured!
It started with a rattle in the engine. I took the head off (big mistake) and then the oil pan. Turns out it had spun a bronze bearing out of the harmonic balancer. Got it replaced and back together.
Now, here's my problem.
It runs very rough. Obviously, one cylinder is not firing.
Additional symptoms are:
1. Took exhaust manifold off. When I turn the engine over with the stop cable pulled out, there is a 'mist' comes out of the front exhaust port, but nothing from the back.
2. There is a little 'burst' of diesel from the top of the injector pump on a regular basis when the engine is running.
3. There seems to be diesel coming back up around the no. 2 injector.
4. I cannot get the return line connector on top of the no. 2 injector to stop leaking, even with new washers.

Is there an easy (or any) way to determine which injector is not firing, and if one is not, what do I do?

Thanks
Ernie

 

[Anonymous-0]

There is an old saying For MFs with the number (8) Long life and realiable tractor 85s and 285s are not. There will always be a problem. For Parades and tractor shows they are good! Sorry! Just the Facts

 

[Anonymous-0]

Loosen the lines at the injector as the tractor is running. If there is no change when loose, thats the bad injector. For the leak on the pump it may be a line or bad sealing washer or gaskets. Blow it off with air and wacth it close to see the leak.

 

[DavidP,South Wales]

Hi Ernie,
First of all I don't agree with the comments below. As far as I am aware we do not even know which engine you have fitted. My info gives the A4.248 and also the A4.318 and A4.318.2, so the tractor can't be condemned that easily.
Did you set the timing correctly between the balancer shafts and crankshaft?
If the engine appears to be running on three cylinders then as has been suggested slacken one injector pipe nut and note the difference in engine running if that cylinder is good or little or no difference if it is the bad one. This will pinpoint the cylinder.
Is the weak cylinder number one or number two. If one of the tappets is tight and the valve not closing fully this may be the 'mist' that you are seeing. Check the tappets again following the 'Principle of Nine' Adjust number one with eight open. Number two with seven open etc.
Is there a fuel leak from the upper part of the pump?
It is not uncommon to have some air-bubbling passing the body of the injector. A leaking washer due to some debris (carbon) can cause this.
Injectors should be tightened evenly and squarely to 12 lb.ft. Occasionally it is necessary to go a little more to prevent a leak.
If the return pipe is still leaking, don't overtighten the bolt and risk snapping it or stripping the thread. Determine which side it is leaking from. Using VERY fine emery paper or 'wet and dry' on a flat surface suach as a piece of glass, rub the leaking side of the pipe in circles until any imperfections are gone. Likewise with the top of the injector but only as a last resort and wash out thoroughly after.
Aluminium washers are best if you can get them.

If you find that one injector appears to be faulty, change it to another location. If the fault moves with it then its the injector but if the fault remains then it may be valves or something else.

DavidP,