Real time help with 2h Governor diapragm!

[Freewheel]

Hi Guys,
I'm taking off the cover of the injection pump governor and engine oil starts pouring out of it. Enough that I soaked a 1 foot square rag in stemming the flow.

Should there be oil in here at all?? I emptied out the waste oil from the normal drain spot through the little drain plug in the side of the IP before I started and just a few drops came out. Then as I loosened the diaphragm cover screws, a steady flow started coming out.

Any ideas??

[Freewheel]

ok I get to answer my own question! The Outer cover of the governor diaphragm housing was full of oil - I don't know where from - but there was a lot in there! The drain plug is on the other side of the diaphragm so the oil couldn't get out. I'm sure it couldn't have been good for the proper function of the diaphragm. Another thing for you 2H owners to worry about...

I'll report back after my test drive. (there wasn't much wrong with the truck - sometimes a bit of black smoke -and slightly variable performance - nothing terrible - but I'm just slowly inspecting and replacing everything suspect in the truck)

[lostmarbles]

Was it engine oil or neatsfoot oil?

Actually it may be hard to tell because old neatsfoot can get very cruddy.

Interesting!!!

I'd guess some previous owner filled it up. (In ignorance of course - because it should only receive a drip or two of Neatsfoot oil every so often. ---- Barely enough to cause any build-up at all.)

If it was engine oil - it would have done the leather (in the diaphragm) serious harm I would think. (By tending to break down the fibres within it.)

[Freewheel]

It's definitely engine oil - and I can't even blame someone else for inadvertently filling it 'cause the Neetsfoot oil filler screw is on the OTHER side of the diaphragm. Either oil is somehow getting into the vacuum hose or getting past the diaphragm somehow.
The original diaphragm is completely oil soaked, but no holes - seems actually in good shape. - it's going to get cleaned in Neetsfoot oil and put in the spare parts pile.


On the plus side, now the truck seems to have way more power in the range between 1800 and 2500 rpm. It use to kind of fade a bit at those rpms and now it keeps the torque that it always had in the low end of the rpm range!

[lostmarbles]

Perhaps it might pay to have a look at the venturi in the throat of your intake manifold to see if there is engine oil around that? Maybe you have your "blowby" fed into your air intake and your engine is "tired" and is carrying a lot of oil into the manifold that way. (I'm assuming you don't have a turbo so the source of the oil won't be turbo seals.) But even so, I find it hard to believe it would flow down that vacuum line to the diaphragm. (I think oil getting into the manifold would simply get sucked into the engine's cylinders.)

And oil can't pass through the diaphragm to get to that vacuum side unless the diaphragm has a hole in it. And besides, you knew about the drain plug on the other side so presumably you had drained that side before and not noticed any excessive quantity of oil accumulating there.

Are you REALLY sure the oil came from the vacuum (outer) side of the diaphragm and not the pump-side????

The vacuum line simply supplies vacuum to the diaphragm to force it to move and the overall air flow through that line is ZILTCH (unless you have a torn diaphragm) so there is no flow to carry oil to that location.

Perhaps the oil got there somehow after a vehicle-rollover? - Although I consider that possibility unlikely too.

Unless someone has another idea - And unless you are mistaken as to which side the oil came from - Perhaps it will remain a mystery. (Although there is still the posibility that a previous owner removed that neatsfoot-adding-plug and filled the cavity with engine oil for whatever reason.)

[Freewheel]

Totally sure the oil came from the outer (vacuum) side. I had to wipe off the cover, shims and return spring 'cause they were covered in oil. And it was skanky black engine oil, so it's doubtful that someone put it in there on purpose.

The truck's got only 246000 kilometers on it, and it doesn't seem too tired. The blowby tube (which IS fed into the air intake manifold) is a bit oily, but nothing unusual.

The rollover idea is not likely. I've had the truck for a year and a half and I've found evidence of a rear end crash, but no evidence that it rolled.

If, however, the blowby tube is where the oil comes from on the pump side of the diaphragm , it makes sense that it is as likely to go down either tube, since they both feed into the air intake manifold.
So maybe the yearly maintenance procedure becomes
1. empty oil from drain screw on pump side.
2 loosen diaphragm cover to release oil buildup on the vacuum side.


As you say -a bit of a mystery- although maybe it's just 22 years of collected blowby condensate.

[Freewheel]

Well, I've had a few days to drive around with the new governor diaphragm, and it feels like a new truck. I've gained a full gear speed on most of the hills around here - meaning hills that I used to gear down to 3rd to climb, I'm now doing in 4th. And I'm even staying in 5th for some uphill grades - which was unthinkable before.

No black smoke either.

If your truck feels wimpy in the 1800 to 1200 rpm range, and you've never touched the diaphragm - it might be time!