First Failure?

[58vintage]

So my FPM has done 17 hours since a full engine rebuild plus some other stuff being done.
I'm after some advise on a possible 1st failure.
I was running the tractor at no more than 1400rpm and shut the throttle down to a fast idle of 800rpm. On the way down there was what I can only describe as a popping backfire and a puff of grey smoke. Since then I have a runny sticky black fluid chugging out where the exhaust pipe slides into the manifold. The engine has been completely rebuilt so maybe something has failed.
I'd think oil but I'm not loosing any according to the dipstick. I'd think trouble with one of the renozzled injectors but I would have thought that would wash the bore and I'd gain oil. I'm also not loosing any water.
What do people think?

[AdrianNPMajor]

In the 17 hours post-rebuild did the engine run correctly up to the point where you began to experience the symptoms described above?
Did you have the injector pump and injectors overhauled?
Best, Adrian.

[Brian]

Take the valve cover off and carefully check all the valves, springs and push rods. I have seen collets drop out if not fitted correctly or valve springs break.

[58vintage]

Morning Adrian and Brian,

Yes the pump and injectors were run up on the benches in work and had a recon, one of my older guys remembers working on these when new. We even managed to get the NL123 nozzles from Delphi diesel, as a power major should have rather than the NL144 that everyone else seems to supply. It's run perfectly before this.

I've just been in the rocker cover Brian, everything looks like it should and is bouncing round correctly, rocker arm to tappit clearence is correct to.

It's a thimble full in 20 mins.

I thought valve guide missed or replaced incorrectly and letting in oil but I'm not loosing any and it feels like that sticky unburnt fuel soot mix.

Suppose it's nothing to get the boys to recheck the injectors in work tomorrow just in case.

Unless you fine gents can think of something I'm missing?

Best regards,

James.

[AdrianNPMajor]

Hello James
The black, oily discharge and white smoke indicate unburnt fuel.
The popping indicates a timing issue.
If the rocker/valve assembly is set up and working correctly, and the timing gears were mounted correctly (as they must have been), then we are back to looking at the fuel delivery.
I may be missing something here. Will continue to ponder!
Best, Adrian.

[Brian]

When she is running, are you getting any miss or smoke or is it just the black gunge? If the tip had gone off an injector and you were getting straight diesel into the engine, I would have expected a miss and a knock as well as the smoke.

Having had it happen myself, I would lean more towards a valve spring failing, what you describe is exactly what happened to me, the bottom coils of an intake spring broke, you could not see it until I got the springs off the valves, but I still got a slight misfire.

I was coming down the road to home, with a new engine and I shut down to draw up at the gate when it went.

[AdrianNPMajor]

Hello Brian and James
Brian, your explanation makes most sense, given the symptoms, especially as it seems the issue was of the sudden onset variety.
I wonder what James will find upon closer inspection.
Best, Adrian.

[RH]

They can also run terrible if a vacuum line is cracked, but you only get bad smoke if trying to work, and they won't idle down all the way. will also miss & pop and such.
Not usually the black oily stuff mentioned above though..

[58vintage]

Morning Brian and Adrian,

No noticeable miss or farting and banging after the initial pop backfire.

The injectors have just come off our hartridge bench and are perfect.

I'll have a lot more detailed look at the valve springs this week.

Reading previous topics I wonder if I've got a little of the old fordson diesel slobber. With the backfire and puff of smoke being a little bit of it igniting in the manifold. I'm only managing just about about 155℉ to 160℉ coolant temp at the moment and if say agrilines 181℉ thermostat would sort it?
Regards,

James.

[Brian]

You could be right, sounds like she needs a bit of hard work on a dynamometer or plough. My Nuffy is a bit smokey and oilly as she has been just ticking over on the potato harvester but I just cleaned the three furrow plough up and she will be on that as soon as the land dries.

[AdrianNPMajor]

I'm not a fan of the instruments on the Power Major and the Super Major.
The oil pressure gauge tells you nothing until something is wrong - a light comes on. By then it's too late to react.
The temperature gauge leaves you to scratch your head - what does the colour banding really mean?
In both cases you can't really beat properly calibrated dials.
I think there is wisdom in the quote below. The first sentence sets up the rationale that follows.
Best, Adrian.

Diesels run most efficiently at approximately 200° or above. A factory equipped 192°/195° thermostat will maintain an operating temperature at approximately 165°-170°. The Powerstroke has such an efficient cooling system, that this low flow when the thermostat is slightly open is normally enough to keep the engine cool. The downfall to this is that the engine -- when our trucks are not under load -- never begins to reach its optimal operating temperature. Our 203° thermostat maintains a minimum operating temperature of 190°. This brings the operating temps up from as low as 170° to as high as 203° depending on the operating conditions of the truck. This is closer to the operating temperature range that is preferable in our trucks for optimal efficiency.
When our trucks are under load and are producing higher combustion temperatures the 203° will allow the engine to run even closer to its optimal operating temperature. If the truck is under load and reaches the 203° setting, the thermostat is then fully open. This means you are at the maximum coolant temperature that the truck will reach. Your maximum temperatures are only a few degrees higher than in stock configuration, but these are degrees that you want for better performance. The best benefits come when the same truck is under a light load and would have a hard time reaching this optimal temperature. As stated above, you will never reach this optimum temperature with the stock 195° thermostat. The end result of installing the 203° thermostat should be slightly better fuel economy, less smoke, and maybe a few extra "ponies" to go along with it.

http://www.dieselsite.com/dieselsite203thermostat.aspx

[58vintage]

Ordered a hotter thermostat to see if that will help and will go find some hard work for it. We are so far from getting a plough in the ground down here it's silly, dad has never known standing water in fields we have it at the moment. Might have to resort to pulling a really heavy trailer up the hills for a bit or one of the 9ft mowers that takes 40 BHP on the shaft just to get them to spin.

[AdrianNPMajor]

Hi James
Any chance of some photos of your tractor? A video of it running would be even better?
This is a frustrating time of the year. It's not easy to find some serious work for our machines. I haven't used mine for a few weeks now.
Best, Adrian.

[58vintage]

Hi Adrian,

I know I keep promising I'll have to get some photos up etc.

I could easily put either loaded 3.5t, 5t or 10t trailers to make her grunt and we have some majorly steep hills on the edge of our place.

Obviously the 10t trailer is going to be to much for a FPM but is it safe to pull 5t?

[AdrianNPMajor]

Hi James
I don't have a lot of experience of pulling heavy trailers, so I'm not the best person to answer your question as to how much weight to pull.
Best, Adrian.

[Brian]

The question should be how much can you stop not how much can you pull Majors do not have the best of brakes.

The problem with bedding an engine in is you need a sustained load for a time, with varying engine revs, pulling her down but not too much, (if that makes sense).

A plough or cultivator is ideal because then load and the revs are fairly constant over a long time. (Say five or six hours) with short periods of throttle down at the ends as you turn.

A load on a trailer only lasts until the top of the hill, unless its a very long hill, you will not work her hard for five or six hours. If you were to take her on a run of say. six hours, with around three tons on the trailer, so she was under constant load for that time then it would work.

[58vintage]

Lol that's a fair point Brian. I'm use to bigger stuff with air brakes not use to thinking can I stop this but well worth thinking about with the FPM.
No the longest steep pull I could manage would be up a field out a gate and keep going up some common ground at the most it would be 0.5 of a mile. Might see if anyone round me has a pto attached dyno, we've got a wheel driven one in work but I don't know how useful that would be to a tractor.
James.

[AdrianNPMajor]

Hello James
Re Brian's point about bedding in the engine, did you do as Brian advises after the rebuild?
If not, you really need to put the engine through this procedure before you put any more hours on the clock.
Pulling a trailer won't really do it.
This is what I did, even before I had sourced mudguards and some decent tyres.
Best, Adrian.

[URL=http://s1216.photobucket.com/user/ ... .jpg[/img][/url]

[58vintage]

That's a good idea Adrian getting something like a mole plough to get her really working. Looks like I'm going to have to wait for everything to dry out before I get things sorted.

[oehrick]

Dry out a lot quicker with some mole drains

[AdrianNPMajor]

Hi James
I used this Morris running-in oil. Once you have a serious bit of work lined up, it might be worth doing a few hours work with this oil in your engine.
Best, Adrian.

http://www.morrislubricants.co.uk/golde ... n-oil.html

[58vintage]

Might well give that stuff a go. We've had a week of dry weather now so we are drying out fast. My new rear tyres are going to be fitted tomorrow so that will help to. Will slap the new thermostat in to.

[58vintage]

Problem fixed with any luck. Put a 181℉ thermostat in and its now reaching middle of the blue section with a 9ft topper on the back for 3hrs.
Put her away now till I can get a mole plough on to bed the engine in.

[paudie]

Hey guys I'm following this story with interest. I see on the last post that you are going to fit a 181 degree thermostat.I understand the reason, but I've herd before, and i think I even read It here on these pages ?. That sometimes this type of higher thermostat pressure may put excessive force on the ageing engine block rubber groves and the single rubber ring at the base of the liners.This may cause the engine oil and water to mix which would be a much bigger issue if it happened than what you are experiencing at present .Just a word of caution, I think I'm correct in my comments ?.if not feel free to correct me ,
Regards Paudie

[oehrick]

The more critical thing is probably not using a pressurised rad cap Paudie - something I was warned about by our local Nuffield parts supplier - in fact he gave me a non press cap to make sure (I passed the pressurised one back in fairness)

Not certain what difference the thermostat change will make but will continue to watch the thread with interest.