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Just another day in paradise

Bluox

Senior Member
Joined
Jun 19, 2010
Messages
1,960
Location
WA state
Just a thought from the past.
Kinda weird to have a one way compression leak.
Some trucks had an air operated heater water control valve that if it leaked it would blow water out of the radiator.
Bob
 

Mike L

Senior Member
Joined
Dec 1, 2010
Messages
1,901
Location
Texas
Occupation
Self employed field mechanic
The truck is a 2007 peterbilt 379 so no air operated heater valve. Your post got me thinking. I guess I’ve never paid much attention to the thought of a one way compression leak. Way back when I worked at a truck dealership we would use the pressure tester and if it built pressure quickly we’d rule out the compressor and then off with her head! I did see one time a guy was pushing coolant and had an overhaul done. Continued to push coolant. That’s when someone noticed the weep hole on the water pump was plugged.
 

kshansen

Senior Member
Joined
Mar 11, 2012
Messages
11,129
Location
Central New York, USA
Occupation
Retired Mechanic in Stone Quarry
Not really directly related to this problem but figure it might help some here. Many years back had a coolant leak getting into the oil of a V16-71 Detroit. Yes I bet everyone says injector tube orings, NOPE! Checked all 16 not a drop. Dropped pan to see if I could spot where on the engine the water was going while putting 15 psi pressure into radiator. Not a sign of a drip. Believe I also had pulled engine oil coolers and tested them with no leaks.

Well end of day and they didn't want me to work overtime so I went home for the night. Next morning walk into shop to see a large puddle of coolant. What the heck? Now could see drips coming from under engine near front cover. Like Mike's engine turns out this one had a plugged weep hole and a bad water pump seal that for some reason only leaked when no pressure on it but as soon as you put pressure on the cooling system to look for leaks it stopped leaking!
 

John C.

Senior Member
Joined
Jun 11, 2007
Messages
12,865
Location
Northwest
Occupation
Machinery & Equipment Appraiser
They swell up when warm and retract when they are cooled off. I helped a young up and coming wrench on one of those this summer.
 

Bluox

Senior Member
Joined
Jun 19, 2010
Messages
1,960
Location
WA state
I would guess... without any air in the system, a small volume could build pressure quickly. Sorta like a skid steer attachment in the Sun, builds hose pressure to prevent connecting to the machine.
Your kidding right?
Bob
 

kshansen

Senior Member
Joined
Mar 11, 2012
Messages
11,129
Location
Central New York, USA
Occupation
Retired Mechanic in Stone Quarry
I would guess... without any air in the system, a small volume could build pressure quickly. Sorta like a skid steer attachment in the Sun, builds hose pressure to prevent connecting to the machine.
I have never had that problem, but actually never had to deal too much with quick connects on hydraulics. I can see that if say you had a cylinder bottomed out and disconnected the couplers on a cold day then came back a day latter in the afternoon with the sun beating down on the cylinder it could build up a good amount of pressure.
 

Mike L

Senior Member
Joined
Dec 1, 2010
Messages
1,901
Location
Texas
Occupation
Self employed field mechanic
A5D8E4CA-5B50-4820-869C-7764FA627EB2.jpeg 4254E558-9ECF-4869-A871-7001266B2352.jpeg Started tearing into my buddies truck today. A platinum kit for a cat was 8-9 weeks out. A long block was 2-3 days out. Considerable more money but when he’s done he’ll have a nice rig. Now here’s where I’m going to start complaining. All the rockers and vva’s are installed, and marked with a paint marker so they’ve been torqued. I have to swap the injectors from the old engine. So that means I have to remove all rockers and vva housings. Wtf? Engine also comes without a new oil pump. Why? Nobody in their right mind is reusing an old pump on a brand new engine. We have to swap all the filter housings, oil cooler, thermostat, on and on. Not one single o-ring or gasket included so he’s placed another large order just to get enough parts to continue.
 

Mike L

Senior Member
Joined
Dec 1, 2010
Messages
1,901
Location
Texas
Occupation
Self employed field mechanic
Stopped at a customers farm on the way home to put a shut off solenoid on a case loader. Found this beauty sitting in the shop. I wanted to swap my labor on the loader for it but couldn’t make a deal.B259B299-2E76-4204-83D4-FE3E756ED61F.jpeg
 

JLarson

Senior Member
Joined
Aug 23, 2020
Messages
656
Location
AZ
Occupation
Owner- civil and heavy repair/fab company
Engine also comes without a new oil pump. Why? Nobody in their right mind is reusing an old pump on a brand new engine. We have to swap all the filter housings, oil cooler, thermostat, on and on. Not one single o-ring or gasket included so he’s placed another large order just to get enough parts to continue.

You act like this is an oversight instead of a design o_O
 

Truck Shop

Senior Member
Joined
Dec 7, 2015
Messages
16,548
Location
WWW.
Pretty normal on a long block. Years back Engines didn't come with jakes-it was a option.
When I worked for a shop in Seattle years ago, it was the distributor for Pacbrake. We would
trade out weeks and one of us would go to Kenworth plant and install up to 6 sets of jakes
in a night on B model Cats. I know I installed my fair share, or so it seemed. Now it's just
standard that jakes come on new engines.

Long blocks normally don't include the outer accessories, other wise it would be a complete assembly.
 

Mike L

Senior Member
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Dec 1, 2010
Messages
1,901
Location
Texas
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Self employed field mechanic
Tied up the engine swap today. It took two of us 35 hours start to finish. Removed engine and transmission, swapped over all parts, new clutch, flywheel turned, new turbos, etc. Of course that had a few extra parts runs included. Truck runs excellent like it should. Test drove it and lo and behold the alternator quit on us. Thinking it maybe got hit with the pressure washer before we started. Now I got a few smaller jobs to do and next Monday I’ll start overhauling a C18 in a Peterson chipper.
 

JPV

Senior Member
Joined
Aug 20, 2015
Messages
756
Location
S.W. Washington
How many hours on the C-18? I have heard they only make it about 5 or 6000 hours in a chipper. We work with an outfit that has 3 Morbark chippers, 2 have C-18s and 1 has a k series Cummins. The Cummins was recently overhauled with unknown hours on it, both Cats are approaching 6000. They just bought a brand new complete engine for 60,000 dollars to have a spare on hand for when one goes.
 
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