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3406B Pacbrake? through connector

Chrisso

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Apr 6, 2021
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468
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Australia
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Diesel Mechanic
I'm hoping the (slightly) older generations can help identifying this through connector that runs through the compression brake housing. Cat part number would be ideal.

I've searched through SIS, came up empty. Thought it might've been a 6I-1486, but that has a round bullet style connector, this one has spade terminals.

I believe it's off a 2EK 3406B, no full s/n sorry. Customer believes he has pacbrakes, but cannot confirm. That's all I've got.

Oh and this picture...

1685156586121.png

Any thoughts?
 

Truck Shop

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I just threw two of those away today, if it has Pacbrakes it will only say Pacbrake.
The Packbrake model is P36, it covers all B and C models. If Jacobs it will say
Jacobs with a series number on a tag, the series are 346B/C/D. To rebuild a set of
Pacbrakes it will use a Jacobs tune-up kit. The internal parts are the same, Cat is
the outlet for Jacobs rebuild kits and parts. Some dealers carry them also. The
rebuild kit number is 143-6479.
When the patent ran out is when Pacbrake started. Located in Richmond BC and
Bellingham Washington. Separate parts can be had but it's a slow boat. The kit here
costs $296.00 now use to be $150.00 and it doesn't contain allot of parts, the box
is big enough for a large pizza containing a hand full of parts. The kit has the pass
through connectors your looking for.
Years ago I worked a winter for a shop in Seattle that was a Pacbrake distributor and
had the contract for installing Pacbrakes on B model Cats at Kenworth factory.
I installed allot of Pacbrakes on B Cats.

Good luck mate.
 

Chrisso

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Apr 6, 2021
Messages
468
Location
Australia
Occupation
Diesel Mechanic
The kit has the pass
through connectors your looking for.

Thanks TS, good info. That kit fetches just over 500 bucks down here, at least from Cat anyway.

The parts breakdown of that kit lists 2 of the 6I-1486 connectors, that's our round bullet style connector. So it ain't that.

It also lists 2 x 170-6273 TERMINAL-LEADOUT... wish I could find a photo of these. Might be an $18 gamble for the customer.
 
Last edited:

Chrisso

Senior Member
Joined
Apr 6, 2021
Messages
468
Location
Australia
Occupation
Diesel Mechanic
No doubt about it... has to be the 025663 Jake p/n
1685174681102.png

Cat converts this to a 170-6273 Terminal-leadout.

Thanks again.
 

Chrisso

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Apr 6, 2021
Messages
468
Location
Australia
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Diesel Mechanic
Sure did, but that protector seems to only marry up with the round 6I-1486 connector... from what I could see.
 

Chrisso

Senior Member
Joined
Apr 6, 2021
Messages
468
Location
Australia
Occupation
Diesel Mechanic
Also found this reference, which when zoomed in is slightly more convincing...

1685177987926.png
 

RocketScott

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Sep 8, 2013
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173
Location
Lexington, KY

Truck Shop

Senior Member
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The parts breakdown of that kit lists 2 of the 6I-1486 connectors, that's our round bullet style connector. So it ain't that.
The rebuild kit comes with both type of pass throughs. But you may as well rebuild those engine
brakes, more than likely tired. The Jacobs 346 used both styles of pass throughs, later brakes used
the bullet type connector, early spade type.
 

Truck Shop

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BTW, I just finished rebuilding a set of P36 Pacbrakes yesterday-Friday using the 143-6479 kit.
Removing a set of worn out Jacobs 349A models, Jacobs doesn't support the 349's anymore.
It was a option/offering for extended weight/GVW or just any GVW. 349's were known as the
Super Jake for the B Model. 349's had twice the valving/moving parts and incorporated a
plenum for extra oil to build more pressure against the slave piston, which caused extra wear
in the slave piston bore, rendering the housing as useless after time.
One huge problem that Jacobs had was achieving closer timing at TDC for opening the exhaust
valves. The 349 corrected that problem with a higher oil psi within the the jake housing, but it
caused extra wear at the slave piston. When it came to the 855 Cummins Jacobs had the timing
worked out, that's why a 855 had better jakes than a Cat. Jacobs never sold that many sets of
349, 349A models, I've only seen maybe 5 sets in my life.
 

Tyler d4c

Senior Member
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Mar 2, 2016
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1,931
Location
Salix Pa
Much like TS I have 2 that I should toss away there yours if you want them!
 

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