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D6c cat loss of oil pressure

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
Lost oil pressure

hey Steve, a bit more info would help. S/N for starters
Mark
HI Mark,
I lost oil pressure on my d6c cat 1974 year serial number 10k11.First noticed a small oil leak up front down by the flywheel pulley,I checked the oil level and was still good so I continued on pushing a tree ridge down. Worked it for about 10 minutes, noticed the engine oil pressure dropped slowly, then the engine completely shut off. Next day I disconnected oil line to the pressure gauge, started the engine, no oil coming up to the gauge, engine stopped again, nowI am dead in the water. Your help is greatly appreciated. Thanks,
Steve
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
Lost oil pressure

Does it turn over? Does it smoke while turning over?
Yes, turns over great, but little smoke. I am going to try new fuel filters this morning, but why no oil pressure? ??Does this machine have a sensor that senses no lubrication and shuts down the machine ?I am lost...
 

bam1968

Senior Member
Joined
Nov 1, 2014
Messages
533
Location
IA
Occupation
Excavating Contractor
Are you perhaps somehow mistaking fuel pressure for oil pressure? Just a thought.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
Lost oil pressure

HI Mark,
I lost oil pressure on my d6c cat 1974 year serial number 10k11.First noticed a small oil leak up front down by the flywheel pulley,I checked the oil level and was still good so I continued on pushing a tree ridge down. Worked it for about 10 minutes, noticed the engine oil pressure dropped slowly, then the engine completely shut off. Next day I disconnected oil line to the pressure gauge, started the engine, no oil coming up to the gauge, engine stopped again, nowI am dead in the water. Your help is greatly appreciated. Thanks,
Steve

Thanks for your input on diagnosing my lost oil pressure. I pulled the belly pan off and the oil pan and found that the oil pump gear bolt sheared off and metal was all over the bottom of the oil pan. I will order one tomorrow morning. I just hope and pray that there is no damage to the engine. Time will tell! Thanks again
Steve
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
Cat service representative said that when you loose oil pressure, the fuel pump automatically shuts down to protect the engine from further damage. That explains why the engine wouldn't keep running. Thanks again for all your help!
 

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
Steve, dream on about you CAT Service Rep comment, instead of ordering an oil pump I would start unbolting the engine, with no oil pressure they will run the crank out in around 5 mins, it's usually marked by a puff of black smoke as the effort to turn builds up.
tctractors
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,379
Location
G..G..G..Granville.........!! Fetch your cloth.
I agree with tc. An oil pump alone isn't likely to fix that however much you would wish it to. Simply for peace of mind IMHO you should be pulling the main & rod bearing caps to inspect. It's very little extra work considering you already have the oil pan off.
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
I think that I will do that. Thanks for the suggestion. Should I replace bearing inserts as long as I have pan off? I am planning on spraying gasoline inside the crankcase.
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,379
Location
G..G..G..Granville.........!! Fetch your cloth.
TBH my first thought would be take a look at a couple of representative crank bearings, and based on what you see start to think straight away about yanking the engine out. Remember you can inspect the crank & bearings but what about the camshaft bearings..? You can't see those. What you're probably going to have to do to the engine at the end of the day will be much more succesfully accomplished with the engine out of the tractor where you can work on it somewhere clean & dry.
 

fast_st

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Joined
Dec 1, 2010
Messages
1,468
Location
Mass
Occupation
IT systems admin
possible for an oil pump pickup to fall off? manual oil pressure gauge?
 

tctractors

Senior Member
Joined
Oct 9, 2007
Messages
2,412
Location
Worc U.K.
Steve, I think you are missing the point some, the only way the oil filter gets bits into it is if the oil pump pumps the oil through the filter? if the oil pump has calved down it's not going to pump ow't, as a matter of interest did you cut the filter pleats out and pull them apart so they are flat, I have been working on CAT stuff around 46 years and will be really happy to think your crank is A1 , as it will be a first, you need to check the main bearings and the big ends, they can be changed in frame but I think you will be Un-Plugging the engine.
tctractors
 

Steve.ahlgren85

Senior Member
Joined
Jun 4, 2016
Messages
399
Location
Darwin, mn.
What do I need to see in the filter, microscopic flakes? I really respect your knowledge of cats, but if I am not seeing anything, what more can I do?It wasn't like I ran the machine for an hour or two. It lost oil pressure and within a minimum the engine shutdown. I am hoping no damage is done. What more should I look at without pulling the engine? I am very confident that the machine will start, not so confident on how it will sound!!!!
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
29,379
Location
G..G..G..Granville.........!! Fetch your cloth.
The flakes won't be very big or easy to see, although the fact that they are not obvious could potentially be regarded as a plus. If there was a significant quantity of really large flakes the engine would have been sounding like a bag of bolts long before you stopped it.

However think of it this way. Any flakes that end up in the filter ended up there because the oil pump was pumping oil round the system. What was your oil pump doing while the engine was shutting itself down..? Not pumping oil that's for sure. Therefore even though the filter does not have flakes in it is not a 100% guaranteed indicator that all is well with the engine. If there is crank bearing damage then it is entirely possible that the debris from that damage never reached the filter because of the oil pump failure.
 
Last edited:

nowing75

Senior Member
Joined
Aug 5, 2009
Messages
898
Location
coatesville indiana
Y generally not good when they stop after losing oil pressure I had a farmer last year forgot to fill the motor with the oil after draining it he started it didn't get above wider I drop the caps and looked at the bearings and only one was questionable I was able to polish it I put it back together so far it's running fine for him you would have to find out why you lost oil pressure I'm not sure how the pump is driven with that engine pump set up
 
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