Jake Rebuild Kits.

This topic contains 2 replies and was last updated by reggie 9 years 8 months ago
February 16th, 2012 8:35pm
We often get complaints from drivers of “weak Jakes”. The coaches I work on have two speeds, high and low. First we verify that the jakes are in fact coming on. If they are active in both speeds, most then do a rebuild of the jakes. My question is, if the springs aren’t broken and the solenoid is working properly, is there any point of doing a rebuild? Keep in mind these are series 60s with over a 1,000,000 MILES.

July 1st, 2012 1:39pm
What about a valve adjustment before they get rebuilt?
July 1st, 2012 8:50pm
This is an example of dead ended oil gallery. The brake head is charged with oil at engine oil pressure but the oil has no place to go. The oil stays in there and any impurities gradually settle out or the oil starts to varnish the galleries where the pistons are supposed to slide. End result: engine brakes slow to apply, partially apply, or fail to apply.

Electrical faults are the most common cause of "fail to apply" but severe dirtiness in the head can also cause a fail to apply condition.

As to replacing the parts during a cleaning, why not? Everyone wants these things to work and be problem free. If they only come off every 8 to 10 years, again, why not?

Another place where dead ended oil galleries tend to be a problem over time: the HEUI injectors on Ford and International engines. Very little oil circulates through the injectors. Again the oil settles out or varnishes the injectors creating hard starting, and poor running of the engine.

All dead ended galleries require that high quality oils AND filters be used exclusively. Oil monitoring and changes need to be done religiously. This is a heck of a lot cheaper than replacing the injectors.

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