When I use my D69U, after about 30 minutes it gets warm and loses power. What would be a suggestion to fix this? I sprayed out the radiator thinking it might be full of dirt but that didnt help either. Anyone else run into similar problems?
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My D69U loses power after a half hour???
- Thread starter daxlw
- Start date
Are the temp regulators working, are they installed? What kind of temp drop from top to bottom of rad? Is coolant blowing out of the rad when hot?
Later Bob
Coolant isnt blowing out. It seems to lose a lot of its guts and power once it gets warmed up. Like a 25% decline in overall power. Is it due to age or do I need to get a new radiator or some other part? Any suggestions will be helpful.
No coolant blowing out is good news, If we knew the temp drop over the rad it would tell us if it needed cleaning internally.
Later Bob
hector gemme
Well-Known Member
Did you check your fan belt if she't loose or the puley is worn and belt slide in
grandpa
Senior Member
have you serviced the fuel system recently?
ben46a
Senior Member
When you say it get warm... Do you mean it overheats or just up to temp?
OzDozer
Senior Member
Clean out your fuel system, starting from the tank, then going through the lines, and then all the filters. I'd say the problem is in fuel flow requirements once warmed up.
Old tanks develop a buildup of cotton fluff from rags, rust particles, dirt, gelled lumps of diesel - and these partially block fuel line elbows and filters.
Does your 9U have a primary, brass mesh screen, fuel filter? Has it been removed and cleaned?
Old tanks develop a buildup of cotton fluff from rags, rust particles, dirt, gelled lumps of diesel - and these partially block fuel line elbows and filters.
Does your 9U have a primary, brass mesh screen, fuel filter? Has it been removed and cleaned?
Old Magnet
Senior Member
What does the fuel pressure gauge read?
sstocker31
Well-Known Member
Just a guess here.....does your machine have a vented fuel cap thats not working as it should???
OzDozer
Senior Member
Yes, the old Cats have a vented cap that can be taken apart, it's full of steel mesh. The hole in the cap can block up, you can discover this by shutting the tractor down after a few hours work, or when it's losing power, unscrewing the cap, and listening closely for the big "sigh" the tank gives, as it sucks in air.
Fuel lines on old Cats are steel, and often rust out and develop pin holes, particularly where they lie closely against the chassis or steering clutch housing.
These pin holes will often just weep a little, which is often not particularly obvious - but the fuel transfer pump can suck in dust via the pinholes, and block up the fuel filter faster than normal.
As OM says, check your fuel pump pressure gauge, if it's not in the green, the fuel pressure is inadequate to produce full power.
Always remember to flush and drain the fuel filter housing as part of filter replacement. A lot of crud can collect down there.
I do not know the last time the it fuel system has been serviced. I will start there, but it will have to wait till the weekend. A little more about what happens before it gets warmed up it seem strong will roll dirt and spin the tracks. but after a while it seem to hit a wall. the temp gage says it is operating at the 3/4 stage in the blue. It becomes sluggish, it wont push, and even has a hard time turning sharp. I also have to drive it back it to the shed in first because it will come to a stop going up a hill if in second or higher. just no power. thanks for the replies. I will keep updated if i can get to it this weekend but we might be getting rain finally.
OzDozer
Senior Member
With these old diesels, it's simple - No power = no fuel or no air. Make sure the air intake isn't being restricted in some manner (critters nests? piece of rag?), and if that inspection shows up nothing, then you've got a severe fuel restriction happening, a short period after warmup. Often fuel will flow adequately through a restriction, then it will gradually clog up.
I once had a Perkins 6-354 in a truck that wouldn't pull after a short period on the road. Shut it off and leave it standing for 20 mins, and it would roar off again, only to run out of puff 5 miles down the road.
It was absolutely infuriating, because I did everything I could think of, that might clear a fuel blockage. New filters, checks for leaks, removal and cleaning of fuel lines - still the same.
Then one day, whilst lying on my back under the truck, with the glass bowl removed from the lift pump, I spotted a flat, fine brass mesh screen, that was inserted into the lift pump housing at the top of the glass bowl.
This screen was full of fine cotton fluff, tiny paint particles, rust particles, and other debris. Removal and scrubbing of the mesh screen took all of 10 mins - and upon re-installation, the Perkins performed as good as a new engine.
The fuel flow was being steadily restricted by the blocked mesh screen, and with increased fuel demand, it would restrict the fuel flow to a bare minimum, thus making the engine die, right when I needed some power.
I once had a Perkins 6-354 in a truck that wouldn't pull after a short period on the road. Shut it off and leave it standing for 20 mins, and it would roar off again, only to run out of puff 5 miles down the road.
It was absolutely infuriating, because I did everything I could think of, that might clear a fuel blockage. New filters, checks for leaks, removal and cleaning of fuel lines - still the same.
Then one day, whilst lying on my back under the truck, with the glass bowl removed from the lift pump, I spotted a flat, fine brass mesh screen, that was inserted into the lift pump housing at the top of the glass bowl.
This screen was full of fine cotton fluff, tiny paint particles, rust particles, and other debris. Removal and scrubbing of the mesh screen took all of 10 mins - and upon re-installation, the Perkins performed as good as a new engine.
The fuel flow was being steadily restricted by the blocked mesh screen, and with increased fuel demand, it would restrict the fuel flow to a bare minimum, thus making the engine die, right when I needed some power.
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Jeembawb
Well-Known Member
Does it have a muffler or a straight stack? If it has a muffler it is possible that a baffle has come loose inside (especially if there is some muffler damage) - what can happen is that a loose baffle can act like a flap that gradually forces the muffler "closed" as it heats up and when it gets to the stage of crippling the engine if you leave it off for an hour the baffle comes back towrds it's original position to allow to breath a little bit for next time. It is an unusual scenario but fairly easy to check for - take the muffler off & put on a straight stack to see if it's better. I have seen it happen recently on a hitachi excavator that had been rolled at some time in history & have heard of it happening maybe a couple of other times in the second hand memories of people I know.
Worth a crack mate. Good luck.
Jimbob
P.S. If it works with a straight stack you can do an autopsy on your mufller and take out the offending baffle and stitch it back up ready for more years of service.
Worth a crack mate. Good luck.
Jimbob
P.S. If it works with a straight stack you can do an autopsy on your mufller and take out the offending baffle and stitch it back up ready for more years of service.
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3rdgendslmech
Well-Known Member
Dax, if you get a blade full of dirt after its warmed up and starting to have the issue, does the engine die down under the load or does the tracks just stop pulling? If its not wanting to pull and will only travel in first and is hard to turn sharply, you could be looking at a torque converter issue.
hector gemme
Well-Known Member
Your d6 have a fuel probleme and if you have a fuel streaner he must be pluged 90%
d9gdon
Senior Member
Whoa, how about that custom twin tilt set up. What's the story there?