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Calling Current Triad Owners


ShaunE

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I don't want to start a war over this dead horse, but I have been wondering about a possible contributing factor to failure.

I read about every Al Eden post on these engines & have most of them pasted to a document that I still send people however, has anyone ever checked the RPM's these tractors are running at?

The point I'm trying to make is the factory throttle-stop bolt on the throttle control linkage bracket is 30mm in length.  On all the Triad engines I have ever seen, there is NO WAY this is long enough to bottom out on that stop-plate to prevent the engine from over-reving if the throttle cable isn't clamped in the correct spot.

When I purchased mine still in dealer inventory a year & a half ago, I performed all the Triad "fixes" that were spelled out.  I additionally did this because it would over-rev & consume more fuel than could be supplied (Impulse Pump) thus sending the governor into a frenzied surging cycle & fall flat on its face.  I simply replaced this bolt with a 40mm bolt so it would make contact with the throttle-stop plate & set adjusted it to 3600 RPM's (No Load) & the problem went away.

I'm just curious if this could have been a contributing factor as well as the other Achilles heels.

Thoughts?

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All of the Triad OHC failures that I have seen are due to severe overheating - caused by valve cover oil leaks which were completely hidden by the engine shrouds.  The oily fins collect dirt and clipping/leaf debris until no air will pass.   90% of the time, the right cylinder valve cover is the culprit - because the mechanical cam activated fuel pump is mounted to the plastic valve cover.  Such a poor design.  If Kohler had only used the trusty pulse-type fuel pumps, metal valve covers and better valve cover gaskets.

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52 minutes ago, victorsnc said:

All of the Triad OHC failures that I have seen are due to severe overheating - caused by valve cover oil leaks which were completely hidden by the engine shrouds.  The oily fins collect dirt and clipping/leaf debris until no air will pass.   90% of the time, the right cylinder valve cover is the culprit - because the mechanical cam activated fuel pump is mounted to the plastic valve cover.  Such a poor design.  If Kohler had only used the trusty pulse-type fuel pumps, metal valve covers and better valve cover gaskets.

I'm not disputing that at all.  I'm simply asking if anyone else has taken the time to inspect that linkage to determine if it indeed stops the engine from over-reving.  All the engines I've seen, it is not possible with that 30mm bolt.  Which would be another design flaw IMHO.

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I had been around a few Triad powered Sovereigns, and RPM was never a concern.  You might be on to something, but the over-rev should have been caught by any decent dealer during the PDI process and never should have made it out the door to a customer.  I would find it hard to believe that the engine would have passed Kohler inspection too.

What RPM did you find yours running at before the adjustment?

A typical pulse pump should put out more than enough fuel to run any twin at least 4000 RPM, probably more.  Your engine would probably run for a minute or more off what is in the float bowl, so any steady stream of fuel into the carb should keep it alive.  Was your governor simply out of adjustment and hunting?  I can't imagine the amount of fuel required to run the engine at 3600 is that much less than what it takes to run it at 4000/4200 RPM.  I would think 4000RPM no load and 3600RPM with a load would need similar amounts of fuel.  3600 with a load may require more - the throttle will be open a lot further with a load than just running fast with no load.

It has been many years since I messed with a Triad, so I can't exactly picture the screw you mention.

 

I guess bottom line is if your adjustment/mod got it running properly, go with it.

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Just all air cooled engines have a 10% speed droop , so if you have  a demand for a true 3600 RPM full load speed, you set your no load speed to 3960 PRM . For generator sets that need a tighter speed droop lets say for electronics, you  can get electronic stepper motors (governor) that will tighten up on the  speed droop to 2% , but they don't come cheap. I don't know of anyone ever reporting the difference . All I care is that the cut grass clears the mower deck and the snow just lands short of my neighbors yard. 

 

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8 hours ago, BLT said:

Just all air cooled engines have a 10% speed droop , so if you have  a demand for a true 3600 RPM full load speed, you set your no load speed to 3960 PRM . For generator sets that need a tighter speed droop lets say for electronics, you  can get electronic stepper motors (governor) that will tighten up on the  speed droop to 2% , but they don't come cheap. I don't know of anyone ever reporting the difference . All I care is that the cut grass clears the mower deck and the snow just lands short of my neighbors yard. 

 

I believe Onan used a different amount of balls in their CCK governors depending if it was used on a generator or Powermax to accomplish the same.  SimpleOrange documented this in another forum.

 

Edited by ShaunE
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On ‎12‎/‎20‎/‎2017 at 10:52 AM, ShaunE said:

I believe Onan used a different amount of balls in their CCK governors depending if it was used on a generator or Powermax to accomplish the same.  SimpleOrange documented this in another forum.

 

You need a heavier spring to react to the additional centrifugal force put out by the additional weights. You can't have one with out the over.

 

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36 minutes ago, BLT said:

You need a heavier spring to react to the additional centrifugal force put out by the additional weights. You can't have one with out the over.

 

You are probably correct. I'll copy & paste the post.  But this is simply a question about experience with the bolt being too short to prevent over-revving.

 

The generator engine as you already know uses a shirt stubby crankshaft, some guys will turn the tapered shaft down then cut a key-way to accept a Lovejoy coupler. Machining can be done with out disassembling the engine if you have a large metal lathe.

Generator 1800 rpm engine uses ten ball bearings in the governor remove the small spring clip to gain access then remove five of the bearings to obtain 3600 rpm.

When reassembling the timing cover make sure the hole on the timing gear with the plastic insert is located in the 3:00 o'clock position. The pin on the timing cover must insert into this hole.

Get the pin location wrong the governor will not work.

Crankshaft end play tolerances  min/max .006 / 012

I've just completed the same parts swap.

 

The slower running 1800 rpm generator engine requires more mass to facilitate the centrifugal forces required to operate the governor. 
 

Centrifugal Governors :

In centrifugal governors, multiple masses know as governor balls, are responsible to revolve about the axis of a shaft, which is driven through suitable gearing from the engine crankshaft. Each ball is acted upon by a force which acts in the radially inward direction and is provided by dead weight, a spring or a combination of two. This force is commonly called as the controlling force and it will increase as the distance of the ball from the axis of rotation increases. The inward or outward movement of the ball is transmitted by the governor mechanism to the valve which controls the amount of energy supplied to the engine.


 

Inertia Governor :

In inertia governors, the balls are arranged in manner that the inertia forces caused by angular acceleration or retardation of the governor shaft tend to change their position. The obvious advantage of inertia governor lies in its rapid response to the effect of a change of load. This advantage is small, however by the practical difficulty of arranging for the complete balance of the revolving parts of the governor. For this reason Centrifugal governors are preferred over the inertia governors.

The governor on the right hand side still installed in generator engine has ten balls, one on the left is from tractor engine.
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