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Cat 304cr mini problem...

truecountry

Senior Member
Joined
Sep 24, 2007
Messages
410
Location
clarksville va
Occupation
Shop Manager and Tech
Ok guys back in the early fall 70 degree weather I was called out to work site ...The 304 couldn't walk its self out of a hole 3 feet deep not a very steep ramp grade out of ditch with out the bucket helping it ....2 weeks later no start ....6000 hours on machine ....Now
Things I have replaced last year all injectors and glow plugs new caterpillar parts
Older tech that was helping me with a bigger job asked me what was up with mini I tolded him and he grabbed a can of ether and said mind if I have a look I said no but I don't like ether, my boss was there and said let him check it out .
Smoked no start .really didn't spin over fast enuff for me
he pulled dip stick and sealed blowbye tube and said spin it over I did and he said rings are gone I asked how can you tell he tolded me watch and boss spun machine over and he said stopped released fingers off tube and air blew out ....Back of my mind I think this is a sealed system no blow bye tube open
I check older threads here often ....I notice one same thing but was slow to start but does start and mention of hydraulic problem
I start back to work tomorrow after 2 weeks off paid for Christmas and new years...Nice I like this
But I think tomorrow I'm pulling hydraulic pump far enuff off engine to see if it cranks and see where it goes from there.....
Ill report back what I find ..
 

74inchShovel

Well-Known Member
Joined
Jan 19, 2008
Messages
164
Location
Washington
Ether in any diesel with glow plugs is a bad idea, both for the motor and the person spraying it-explosion, motor damage etc. Check glow plugs, make sure they are getting enough voltage, if you suspect rings do a compression test. If you have to squirt something in a diesel to start it, use WD 40. I'm not sure your reasoning behind pulling the pump, but I don't think your solution lies in that direction. At 6000 hours rings are a good bet.
 

murphy777

Well-Known Member
Joined
Mar 14, 2010
Messages
130
Location
Weybridge, Vermont
Occupation
mason/landscaper
have you checked the fuel pump? it would be nice if it was something that simple….new rings sound like a pain, good luck
 

truecountry

Senior Member
Joined
Sep 24, 2007
Messages
410
Location
clarksville va
Occupation
Shop Manager and Tech
have you checked the fuel pump? it would be nice if it was something that simple….new rings sound like a pain, good luck

Pump was good ....Compression was way off ...421 was borderline ...1 -352 ..2- 85.. 3- 120..4 -50
One broken ring on 4
stuck ring on 2-3
rings worn on 1

Rod and main bearing looked great ..
Called cat and got prices on boring and checking head
Was tolded they rather bore and sleeve cylinders then over bore 025 and new pistons and rings Hmmmmmmmmm
 
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