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Discussion Starter · #1 ·
Newbie Here

So I was looking for a Jake and see they are few and far between
So Questions I have are:
Has anyone tried using the 71/92a?
Is the bridge still available? 71/92a use a different type
Last have not found the switch the screws into the governor maybe I'm not looking in the right place or what it is called

Thanks
Bill
 

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A Jacobs Engine brake from a 71 series or 92 series engine will not fit onto a 53 series engine.
The proper Jake Brake for a 53 series engine is a Model 53A

To install a Jacobs engine brake you need:
- a Jacobs Buffer Switch (screws into the governor body where the buffer screw threads in)
- a valve cover riser, or a cast aluminum Jacobs extended valve cover
- Master and Slave Jake Brakes (One master can drive one, two or three slave cylinders - on a 4-53 you can have one master and three slaves (single stage engine brake), or two masters and two slaves (dual stage engine brake - low and high))
- flexible or rigid oil lines
- right side rocker arms with the Jacobs bridge (one rocker arm with bridge per cylinder)
- longer rocker arm retention bolts (two are necessary per cylinder)
- clutch/neutral safety switch
- a switch to activate the Jacobs Engine Brake

An entire setup for a 4-53 can run you anywhere between $500 and $3000 depending on how lucky you are finding a set.
You can still buy the 53 series engine brake from Jacobs, but it is roughly $1000 a cylinder for the kit.

Take a read through of the Jacobs 53A PDF:
http://www.jacobsvehiclesystems.com/files/support/docs-pdfs/018411A.pdf

The 71 and 92 series Jacobs Engine Brakes were much more popular, as they were used in the automotive field extensively, whereas 53 series engines were not. You can find 71/92 series Jacobs Engine Brake kits for 8V71/8V92's on ebay any day of the week for < $500 for the complete setup.

Chris
 

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Discussion Starter · #3 ·
Thanks for the reply

Guess to rephrase the question
Has anyone tried to modify the 71/92a to work on the 53?
And I take it I can still get the Bridge and Buffer switch from Jacobs

I do not have 3k to spend on a brake :(
I do have a drill press and know how to use it
I have installed a Jake before but it was on a 262 and long ago

Thanks
Bill
 

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I think the quick and dirty answer is, if it could be done everyone would be doing it and the price of the 53 series jakes wouldn't be what it is.
 

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Discussion Starter · #5 ·
Thanks
Guess I will call the dealer see how much the Jacobs bridge is if they are to much I will make my own.
Then order a Jacobs Buffer Switch
Think I will run 2 masters
Bill
 

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Discussion Starter · #8 ·
I have found nothing used corse Calif is a non 2 Cycle state
Grigg PM me your address or paypal I will get one
I am cheep not going to pay 300 bucks for a set I will just make a set

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Bill
 

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I was referring to the 4 Bridges
I'm confused, even if you did have the right rockers or made them from scratch, how would that help you if you didn't have the right jake units? If a 71 or 92 unit would work, looks like Jacobs could have saved themselves a whole lot of tooling expense over the past 5 decades and made a one brake fits all model.
 

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I'm confused, even if you did have the right rockers or made them from scratch, how would that help you if you didn't have the right jake units? If a 71 or 92 unit would work, looks like Jacobs could have saved themselves a whole lot of tooling expense over the past 5 decades and made a one brake fits all model.
The brake unit bolts to the rocker stand bolts with special longer bolts. the 71/92 rocker stands are spaced about 1/4"farther apart than the 53, and the holes thru the jakes are spaced accordingly. Plus, the jake is operated from the injector push rod, which is spaced closer to the rocker stands, and the exhaust bridge is also closer to the stands on the other side. Any one of those problems could be dealt with in a number of creative ways, but they all add up to not worth it, and beleive me, I have spent many nights thinking about it...

I am likely to dive in and make some 53a jake replicas at some point and offer them for sale. I'm guessing I could do alright at $500 per cyl. We'll see. I'm at least going to make 3 for myself. I also have a Mack Dynatard type system for the 5.9 cummins almost completed and plan on offering them for sale at some point.
 

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How's the set up for the 5.9 going to work?do you Have pics of work in progress? Id be interested in to setups.
 

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The brake unit bolts to the rocker stand bolts with special longer bolts. the 71/92 rocker stands are spaced about 1/4"farther apart than the 53, and the holes thru the jakes are spaced accordingly. Plus, the jake is operated from the injector push rod, which is spaced closer to the rocker stands, and the exhaust bridge is also closer to the stands on the other side. Any one of those problems could be dealt with in a number of creative ways, but they all add up to not worth it, and beleive me, I have spent many nights thinking about it...

I am likely to dive in and make some 53a jake replicas at some point and offer them for sale. I'm guessing I could do alright at $500 per cyl. We'll see. I'm at least going to make 3 for myself. I also have a Mack Dynatard type system for the 5.9 cummins almost completed and plan on offering them for sale at some point.
You may want to tread lightly about making your own Jakes and selling them. Jacobs still sells them and they may be patent protected. If there aren't any legal issues then go for it! I too have looked into making my own 53A jakes and may well do it someday, but they won't be for sale.
 

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Keep in mind new price for 53A Jakes with all the hardware is about $1,000 per cylinder, that's all new.
I couldn't make them for that and do as good a job as Jacobs does at the same time.
 

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Keep in mind new price for 53A Jakes with all the hardware is about $1,000 per cylinder, that's all new.
I couldn't make them for that and do as good a job as Jacobs does at the same time.
Are you guys sure jacobs is still marketing and making these? I've called a couple times and I can't get new jakes OR tune up kits for my jakes from the dealer....none in stock, listed as obsolete and none in the country.
 

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Yes, I just checked prices last week, and ordered some bridges and long bolts.
The small parts I've needed in the past Timothy at Leid's has always had or could get quickly. Only exception are the cast iron spacers, they're long gone, everything else I'm pretty sure is available.
 

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Discussion Starter · #19 ·
Been to hot for me to do anything outside on the 453 still hoping to get the 71/92 to work if not I can make a new housing that will
I will look into making a spacer I do a 4" blower spacer for ruderon dot com
This will just take time I'm old and slow these days

Bill
 

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huh. any idea what tune up kits go for?
I forget... something less than 2K for 6 cyl worth. Thinking it may be cheaper to piece together what you need and or just buy the seals and not the pistons if they're still OK . Some of the rebuild parts are same as 71/92 and those are reasonably priced, which is why it may be cheaper to assemble the kit from individual part numbers, haven't checked yet.

Grigg
 
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