Wet vs. Dry

[Big_Cajun]

Hello Gents:

Need some ideas and I know you've got plenty for me. I know the difference between wet sleeve engines and dry sleeve engines, but I want to know which is better as far as durability, life, rebuildability, etc.

Also, Wet clutch or dry clutch?

I was also reading up on inboard vs. outboard planetary gears. I also hear of something called a bull gear. Clarification, which is better, etc.?

Indirect vs. Direct fuel injection...which is more efficient, better, etc.

I'm just trying to learn as much as possible about the options available. I want to be an informed buyer.

Thanks for the input. I know that this may start some debates, but I want a feel for what your thoughts are.

Thanks again.

BC

 

[HGM]

BC,

I cant comment much on the other stuff, but I'll give my vote for direct injection. Its generally quieter,provides more performance, and lower emmisions. Most new diesels I am aware of are DI. Though, I'm not sure about tractors... Been doing some reading huh? /forums/images/graemlins/cool.gif

If I remember correctly,wet sleeves require anti-cavitation additives in the coolant to avoid cavitation from electrolysis....

Wet clutch, do tractors use them??? Thought this was just only available in motorcycles. Not sure of an advangage to either....Maybe the wet clutch would provide a little slippage and reduce heat?

In vs Outboard planetaries...... I've got a pretty good grasp on planetaries, but never heard of these types.

Good luck, I'll be watching this to learn more myself.. /forums/images/graemlins/grin.gif

 

[daTeacha]

Clutch and brakes -- the general industry consensus seems to be that wet is more resistant to heat buildup for both, especially under heavy loads at low speeds such as in ag equipment. You'll notice these are usually found on the bigger machinery, even in the CUT size ranges. Oil is better at removing heat from the metal than air is when there isn't a lot of fast moving air available like there is at highway speeds. On higher permformance cars there are special ducts to direct air at the brakes to help cool them. The cooling is necessary to keep the brake fluid from boiling and vaporizing, causing failure.

The thought of a device that works by friction running in an oil bath is a little counterintuitive to me, but they've been around a long time and work well, especially when subject to heavy loads, compared to dry units.

 

[wushaw]

Wet sleeve motors are usually large displacement motors like in OTR trucks and avg 800k - 1m miles before inframe ovehaul. I would figure the large ag tractors would be the same.

 

[NHeuro]

A wet clutch is the best chose, but don't worry when it isn't available.
It depends of the model, the brand and the Hp of the engine.
There are also different dry clutches like a organic dry one
or a cerametallic dry clutch.
The cerametallic is the best but also the expensivest.
And the wet clutch is better as an cerametallic clutch but it is more expensive a it.
But it depends of the hp and if you have a good brand, i don't think you need to worry about the chose of the engineers.

 

[Big_Cajun]

I can't believe that these are all the comments on this topic...Are tractors built in such a way these days that these differences don't matter?

Please fill me in.

BC

 

[RoyJackson]

</font><font color="blue" class="small">( I can't believe that these are all the comments on this topic...Are tractors built in such a way these days that these differences don't matter?

Please fill me in.

BC )</font>

I think you'll find dry clutches on older designs...my 790 Deere has a dry clutch.

I'm sure the wet clutch may be better (longer lasting) but dry clutches have been in tractors a long time.
As long as one is not abusive on a clutch (riding the clutch, for example), i reckon the dry clutch will last 1000 hours or more...or ten years, in my usage.

 

[daTeacha]

And a lot of that will depend on what the clutch does -- tranny, PTO, both, shuttling, etc. I'd expect more than 1000 hours. Both of my 8Ns were well past those hours, just based on age, and neither showed any sign of having been "broken" to fix the clutch. All the bolt heads had intact paint and so on.

 

[NHeuro]

I've a friend and now he is abusing his DRY clutch for more as 1800h, the tractor is 4 years old. But it depends a lot of the usage.
Like using the clutch in turns to slow down or using him at 2500 rpm...

 

[3RRL]

</font><font color="blue" class="small">( As long as one is not abusive on a clutch (riding the clutch, for example...)</font>

I figure this would apply to wet clutches as well? They have a life span dependant on useage as well. Correct me if I'm wrong here...