Best way to trailer turbo'd tractor

[KennyG]

I am skeptical that the wind could spin the turbo enough to cause a problem. However, if I was shipping any item of equipment a long distance, I would cover all openings to prevent trash, moisture, salt water etc from getting into it. I know we require all pipes (I'm talking about carbon or stainless water pipes) to be completely sealed when they are shipped to protect the inside from corrosion. I would guess this would be reason for tractors being shipped from the factory this way, but only someone from the manufacturer could verify this.

 

[s219]

One thing I remember about turbos from the old days is that they could "coke" oil just by spinning without sufficient lubrication pressure and/or cooling, and this could happen to a turbo if an engine was shut down abruptly. Old-timers will probably remember letting turbo engines idle down before shutting them off.

I am sure most of that problem was due to the turbo already being super hot (the housings can get dull cherry red in normal use), so I doubt this could happen on a cool turbo being towed with wind blowing back across the rotor vanes. But it reinforces that the turbos and bearings and their passages are dainty.

In later years, the problem was solved (at least on cars/trucks, not sure about tractors) by providing the ability for coolant and/or oil to keep passivley circulating to the bearings (coolant loop may have a thermal siphon backup loop or design built in).

 

[TomSeller]

Okay, someone needs to put their mouth over their exhaust pipe and blow in it to see if the air goes anywhere as an experiment.

 

[Winmac]

Just a few thoughts.
On multiple cylinder engines it's almost a certainty that one cylinder will be in valve cross over at any given time when stopped.

A low pressure acting on the stack would draw air out of the exhaust ( acting in normal rotation)would this not turn the turbo?

Turbo bearings are plain bearings or (friction bearings), not ball bearings. Plain bearings rely on precision polished surfaces and lubrication, take away lubrication (oil pressure) and it will not take much to damage the bearing surfaces.

 

[ritschner]

Just a few thoughts.
On multiple cylinder engines it's almost a certainty that one cylinder will be in valve cross over at any given time when stopped.

A low pressure acting on the stack would draw air out of the exhaust ( acting in normal rotation)would this not turn the turbo?

Turbo bearings are plain bearings or (friction bearings), not ball bearings. Plain bearings rely on precision polished surfaces and lubrication, take away lubrication (oil pressure) and it will not take much to damage the bearing surfaces.

That was my point, you do not need heat or even high speed to ruin a plain bearing, just some prolonged rotation without lubrication. With today's oils it is less likely to happen, but why take the chance?

 

[Sodo]

?it is less likely to happen, but why take the chance?

Thats the burning question. ----> Is it a real concern?

There was an interesting point that the valve overlap could open a path for air flow, but that's only if the throttle was left open (or no throttle plate?).

Certainly prolonged rotation could ruin the bearing. I'm gonna assume that (throttle plate left open and) after rotating lazily for 27 months, friction could increase a little, at which point it stops rotating and,,,, well it's stopped now. I don't see it burning up. Nor do I see anyone trailering anything for "27 months" or any duration long enough to even increase the bearing friction. Then someone starts the engine and it gets a fresh squirt of oil and exhaust pressure.

Until an experienced mechanic gives a credible account of bearing damage as the reason for covering the exhaust,,,,, (not birds scooped, or gravel, bees nesting, heavy dust etc in the exhaust) I am writing it off as an old husband's tale.

 

[namesray]

Ok. So far I have gathered that yes some have heard of this issue, while others have not.

It has been mentioned that yes there is a way the air forced in the exhaust "could" find a flow circuit/route through exhaust, through turbo, and open valves if engine happens to stop in such position.

Others have actually seen different equipment exhaust being covered during transport.

Some have mentioned that other damage could occur through dirt/debris getting up exhaust to turbo and maybe into engine. (I do haul on a lot of dusty dirt roads.)

I have ran equipment where the turbo was ruined or weak, and boy they have very little power when really needed like on hills and such. Almost makes the piece of equipment useless, or atleast very inefficient.

So...., with all that being said, wouldnt it be a "piece of mind" sorta thing to just back the tractor on trailer for transport if at all reasonably possible???

 

[Sodo]

If there is a genuine risk to the turbo I'd be interested to know the real problem was so I could make a decision with regards to real prevention. Accepting these things for the "peace of mind" doesn't provide peace of mind. Peace of mind comes when you understand the problem and the solution.

I can see covering a vertical exhaust stack to prevent entry of foreign objects during transport.

 

[C4Ranch]

Wouldn't a FEL deflect the wind if your exhaust was down low like L and MX's?

 

[tjkubota93]

Thats the burning question. ----> Is it a real concern?

There was an interesting point that the valve overlap could open a path for air flow, but that's only if the throttle was left open (or no throttle plate?).


No throttle on a diesel. Unless you mean egr throttling plate on 6.0 and it is normally open. Very likely one cylinder lands with valves in overlap-because one is going to land near tdc compression and companion cylinder will land on tdc exhaust.

I would cover it if getting on highway.

Pushing air past a pipe makes a vacuum. Anyone remember the old pcv draft tubes on old cars? Sucks pcv gases outta the crankcase and lets them into the atmosphere or liquids drip onto the road.