Look under the fitting that the hose is hooked on there should be a 22mm bolt head .Take the bolt out should be a filter in it. If you haven't done so already blow hose out.
Bob
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Cat 311B weak hydraulics
- Thread starter Theralfinator
- Start date
Bob
As i finally stopped trying to do three things at the same time, ( the con. of working alone ), I re read this conversation and understood that I made fool of myself! I didn’t really paid attention to what I was reading. My train of thoughts was that PRV leaking internally could drop the powershift pressure when it was not supposed to and load up the engine, and when it was heating up it was leaking even more. Then my overloaded brain switched for some reason to problem of leaking seals and overfilled gear drives, which when overfilled get hot and the hotter they get the more load they put on engine. Then I thought that we are talking about CAT excavator and it supposed to have Rexroth pump which is bent axis and don’t really have the case drain, so my overtaxed brain just turned auto pilot “on” and carried on this gibberish! Until I finally finished what I was doing, look at what I wrote and realized that I screwed up!
I apologize! I’ll try not do it again.
You should have K3V63DT in that machine laying on its side. Unless someone installed something different before you bought it. So the fact that you don’t really have the black smoke kinda throws the pump overload and air deficiency out of window.
The correlation of the ambient temperature and severity of the problem is the interesting one, though!
But at this point,if I don’t get some sleep - I am bound to make even bigger fool of my self! Good night!
Dave Neubert
Senior Member
If you can plumb a gauge in the fuel system and see what kind of pressure you have and see if it dropping under a load. First find out what the fuel is supposed to be I would think 20-30 lbs but not sure
John C.
Senior Member
Boost pressure in the intake manifold is usually measured in inches of mercury. It's been a long time since I've done it but I remember most engines in this application running around thirty inches of mercury which is about 15 PSI. The trick will tell you whether or not your engine is putting out the horse power. If you load the engine up and can maintain that boost at around 15PSI, the engine is likely working as it should. If you load up though and the engine maintains the boost and the machine is still slow you know the issue is in the hydraulic system. If you have a fuel or air induction problem it will show up right away on boost pressure.
Theralfinator
Member
Ok, I see what you're talking about now. That nipple is actually the banjo fitting I'd read about.
Attachments
Theralfinator
Member
The manual specs 11.0 to 35.5 psi for the pressure out of the transfer pump. I'm planning on measuring this through the bleeder port on top of the fuel filter housing. That should give me the pressure after the filter, right?
Dave Neubert
Senior Member
yes
Theralfinator
Member
Where would I have to hook a gauge into if I wanted to check the pressure of the main fuel injection pump?
Dave Neubert
Senior Member
Never heard of checking injection pressure as the injectors have a set pressure pop off pressure. if it pops the injectors it should be OK If it cranks good you have enough pressure
He probably meant pressure inside pumps cavity.
Theralfinator
Member
I wasn't able to find the right fitting to hook my gauges up to read lift pump pressure or intake manifold pressure but here's an update.
The machine was run another couple times in high 40s F to low 50s F ambient temps and it ran awesome. Hydraulics had all kinds of power and there were no overheating issues.
Yesterday we pulled it inside, drained and flushed the fuel tank, blew out the line from the lift pump to the tank, and cleaned out the banjo fitting on the lift pump. Attached are some pictures of the screen in the funnel showing some of the gunk and water that was drained along with some shots of what was inside the banjo fitting.
We took the intake hose off the turbo to have a look and the turbo is shot. Quite a bit of play on the shaft, the blades have started rubbing against the housing, and the leading edge of the blades (not the edge rubbing against the housing, but the part facing the incoming air) have a bunch of wear. So looks like we'll be putting in a new one before we get too carried away next year.
We also took samples of the coolant, engine oil, and hydraulic fluid. We have no idea how long the hydraulic fluid has been in there or what the previous owner put in so it very well could be the wrong oil for the temperatures we have during the summer.
A bunch of the foam around the radiators is deteriorated to the point where it's clearly letting air move around the coolers so we'll have to address that issue as well.
Hopefully we can get her ready to hit the ground running next season. Thanks for all the help!
The machine was run another couple times in high 40s F to low 50s F ambient temps and it ran awesome. Hydraulics had all kinds of power and there were no overheating issues.
Yesterday we pulled it inside, drained and flushed the fuel tank, blew out the line from the lift pump to the tank, and cleaned out the banjo fitting on the lift pump. Attached are some pictures of the screen in the funnel showing some of the gunk and water that was drained along with some shots of what was inside the banjo fitting.
We took the intake hose off the turbo to have a look and the turbo is shot. Quite a bit of play on the shaft, the blades have started rubbing against the housing, and the leading edge of the blades (not the edge rubbing against the housing, but the part facing the incoming air) have a bunch of wear. So looks like we'll be putting in a new one before we get too carried away next year.
We also took samples of the coolant, engine oil, and hydraulic fluid. We have no idea how long the hydraulic fluid has been in there or what the previous owner put in so it very well could be the wrong oil for the temperatures we have during the summer.
A bunch of the foam around the radiators is deteriorated to the point where it's clearly letting air move around the coolers so we'll have to address that issue as well.
Hopefully we can get her ready to hit the ground running next season. Thanks for all the help!
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