69 Case 580CK...Loses Power under load

[rasman57]

My first backhoe for helping me out with general clearing and cleanup of a cabin site in Michigan. I bought this old worker with no illusions and understanding a 40 year old TLB machine will need some attention. I have fooled around with old cars and trucks for 25 years so it appeals to me to have an older fairly straightforward machine. It sits next to an old Allis Chalmers 1960 D-14 loader tractor that really does some chores for me.

The good news.... It is clean, has been well maintained, starts right up and runs smooth with no load and works well. The bad news.... the old gas engine is tired and smokes, consuming about a quart every 3-4 full work sessions and when put under any load (even moving from a stop in gear) I really have to goose the rpm's to allow the engine to "catch up" and then sort of over throttle to compensate. This is both the movement of the machine and/or the use of the hoe. Any up hill drive and she is sure to bog and stall if I do not really get the revs up.

When I bought the machine I used it a bit and had soem of the power issue but not nearly as bad. I stored and parked it all winter. In the spring I found the governor pivot arm was almost froze solid in place and took me a while with the PB and some tapping to free it up to get throttle control back but the under load loss of power is worse. I nurse it and nudge the throttle up and ease into work to get it done and allow the engine to bog but not stall usually. I have no experience with a governor other than what I have done to free up the pivot a bit. Besides doing a compression check next weekend and sorting out the issue of worn rings/valves and some engine work in the future, is the governor operation suspect in some of this bogging down under load? I would like to work it through this season if I can.

Can anyone explain how that governor is designed to work. Does a load on the tractor relate to the governor responding with increase revs? One of the old timers in the cafe told me that the early Case engine governor set up is the most mickey mouse engineered deal he has seen and they were prone to problems with linkage and freezing up with lack of use. I guess if I knew what is supposed to happen then I could
help troubleshoot a bit. Appreciate your experience and input. Ralph

 

[rasman57]

Some progress....

I was able to see the exploded view of the timing cover and governor assembly on the CASE Construction Parts Search site and am thinking that the pivot shaft is allowing the throttle linkage to work BUT the actual governor mechanism must not be working. I am wondering if the weights fail? They become stuck or corroded in place? The diagram shows the shaft assembly which I think contacts a round bevel like part that must be pushed in and out from the gear on the front of the camshaft? Anyone have any insight on what to replace or look for when troubleshooting a non working governor on the early 580 gas CK? Once I get into the cover it may be evident but I do not like to go searching and wondering without some idea. I am hopeful some experience of others may be useful. I know the pivot shaft is moving as the throttle works but I am convinced now that the governor is not and that is causing the failure of the engine to respond under load. Ralph

 

[Phil]

A quick check for governor action is to suddenly place a load on the machine, like lifting the boom, and have someone watch the throttle shaft, while you do this. If the throttle shaft does not move, your governor is not working. Could be linkage adjustment, worn linkages/pins, a spring problem or in the governor assembly itself.

I quickly went over the service manual and it does mention disassembly of the governor itself. " weights must swing freely on the hinge pins. The pin shoulder must be tight against the gear. Also check the weights for excessive wear in the grooves where they mate with the governor shaft assembly".

There is a page on governor and throttle shaft adjustment.

Usually, the throttle lever/foot pedal is only changing the pressure on the governor 'arm', and the governor is actually setting the position of the carb throttle shaft. With this in mind check that the rod between the governor and carb has been adjusted properly(not too long or too short). I would not take the timing cover off until you had to. It is possible the mechanism itself has gotten gummed up but rule out other possibilities first. Phil

 

[rasman57]

Phil,
Appreciate you taking the time..... I will check all of the linkage and adjustment possibilities first. I had not thought of an independent check of the operation of the governor. I am just about certain though after thinking about it that the governor is not operating. I may get lucky and free it up but I bet I am diving in to the cover in the future. Ralph

 

[OneWelder]

I do not know on your tractor - but on a lot of the gas jobs you could advance the throttle - then if you grabbed the one of the two rods going to carb ( one will move the other will not ) pull it to slow motor down, the Governor rod should immediately try to speed it up

 

[Phil]

I think OneWelder has really got good advice there.

On the 188 diesel engine, when removing the timing cover, the crankshaft seal always needs replacing and about half the time the pulley needs a speedi sleeve repair, it's a SKF 99212. Not sure if the gas engine uses the same pulley or not. Also the front of the tractor has to be unbolted and moved ahead about 1 1/2" to give enough clearance to get the pulley off the end of the crankshaft. It's a big job on a diesel 580CK to remove the timing cover. Phil