View Full Version : Surging Govenor

12-25-2006, 02:07 PM
Looking for some suggestions on how to cure a surging govenor on a " U " series D-2. The engine will surge at idle as well as under power... when pulling a disc it behaves when working hard such as climbing a hill, but will begin to surge when the load lightens.
I have been told that worn bearings or flat spots on the govenor rollers can cause this condition.... the bearings and shaft all look good... the 2 rollers each have a small flat spot worn in them ( see pic ) .... could those small flat spots account soley for my problem ????? or is there something else to check ????
In may 2003, Mike Cremonini posted on this forum that he had cured a surging D-2 govenor by " tweaking the govenor spring " .... can anyone elaborate on this ?? Thanks , Wayne

12-25-2006, 02:51 PM
Yes a gov. spring will cause it & the flat spots & bearings worn too but the pins in the weight assem. is a factor & also a sticky injection pump will cause that problem.Unhook the rack linkage from the gov. & see if it is free of binding but I think the big problem is in the weights & related parts that,s the cause & the thrust bearing could contribute too so this is the places to check out.

12-25-2006, 03:46 PM
look for slack or binding in something, spring is unlikely to make much difference there.

12-26-2006, 10:58 AM
Thanks for the suggestions..... I did order new rollers and bearings..... I will inspect the linkage, injection pumps, and weight assembly more closely before reassembly. Will post the results when shes running again. Wayne

12-28-2006, 05:59 PM
I had my dads 4U in bits 2 time and it is fine under light load but slugish under heavy load every thing looks ok?????:confused:

12-28-2006, 06:48 PM
When I purchased my Cat 10 it had a surging governor. I thought when I tore it down that I would take the governor apart and see what was wrong. I had partially taken the tractor apart and had to move it. When I did it ran like a clock. After checking things out I discovered the air cleaner was completely clogged with gunk,and that was one of the parts that I had taken off. The engine was starving for air making the governor surge. I don't know if it would work the same on a diesel but might be worth checking. - Wally

12-28-2006, 07:10 PM
D23J What it sounds like with your dads tractor is the gov. spring is weak & also check the RPMs & should be 1710 RPMs high idle with no load on the engine (tractor setting).The correct gov. spring for it should be a 5F1940.All components inside a gov. has to balance out & when they don,t then power & performance suffers from it.

12-28-2006, 07:57 PM
I will second brewzer, if the other things you check out aren't the trouble, that air cleaner is a good place to start.

12-28-2006, 08:14 PM
Every time I washed my 5J D2 the governor would get sticky. It would over speed when a load was lessened, then die dead when it was slowed to what should be idle speed. I dried out the back housing, hosed the rack down with a good penetrating oil and put in a new cover gasket with some silicon sealer. No more trouble. It doesn't take much crud on the rack to make it pretty darned sticky.

12-29-2006, 03:20 AM
Thanks SJ, the governor spring is not a good part number any more so I well have to look for a used on as every thing else is ok and they do not give specs for the spring thanks.Have checked the air cleaner more than once.

12-29-2006, 06:02 AM
D23J, Also you could try a 5F1941 or 5F6413 spring in it but you,ll have to possibly reset the RPMs as they are slightly different in tension so will effect the RPMs. I have replaced dozens of springs in larger engines than the D2 with the 5F6413 spring & helped the engine to work better but again the RPMs had to be reset.In bigger dragline Cat engines they were the answer when a power problem & performance was the trouble.The 5F6413 spring is used in some applications of the D311 industrial version engines & the D2 of yours has the D311 in it but again the RPMs will need to be reset & really should whatever spring you put in, new or used.

12-29-2006, 06:36 AM
Left my books with the tractor and need the correct part number for my govenor spring. Its a D6-9U 29187 ser# , of course it has the D318. Understand that there can be differences with that engine so it needs to be for the specific tractor D6. Not sure if it is like other parts but have found that some parts change with that (very) late serial #. (Experience is a tough teacher) Thanks for the assist.

12-29-2006, 08:08 AM
I don,t have it in my book quite high enough but yours I,m sure has the counter bored nozzle so the 5F6413 is what it calls for & the other nozzle uses the 5F1941.My book calls for 1540 RPMs in the book I have but the later engine in them were basically the same specs on that part of it.

12-29-2006, 04:27 PM
SJ just tried dealer for both springs so I will have too try for a used one thans again.