14-19 down lock actuator

D

Dover

Member
Hello all, Happy Holidays

What I've learned;
On my 14-19 the downlock release actuator has two ball bearings in it, one small and one large, along with a spring. It is critical that they are installed in the proper order. The bottom, or pressure side for retract, the hardline connects via a AN fitting. Just above the AN fitting the spring is located. Above the spring is the large ball bearing, following that, and above, is the small ball bearing. Any other combination or omission could be catastrophic. For instance, if the spring is omitted, the gear will retract normally but will lock in the up position. The large ball bearing will cause a hydraulic lock against the AN fitting thereby not allowing the gear to extend. Be aware that if you take the AN fitting off for any reason, you will have parts falling out.

Hope this helps the next guy.

Merry Christmas
 
Dover, do you happen to have one of the first dozen or so 14-19s made? I have heard of this down lock actuator ,but never seen one. Do your retract struts have the hinge point between the long and short portion below centerline or on centerline ? I have only seen one early Cruisemaster with gear that at first glance looks like Cruisair gear. I understand that Johnathens Cruisemaster had this type of gear, and my theory (and it is only a theory) is that improper adjustment of the gear after a repair is what caused the metal fatigue that caused his gear collapse.There is a Service Bulletin on Cruisairs concerning this issue, and if you have one of the early Cruismasters it would be good to look at it and see if the adjustment advice should apply to your plane._____I hope this helps.____Grant.
 
Serial no. 2032. Hinge point is below centerline. From the pics of his plane it looks the same. I inspect that area with lots of care and time. What is the SB number that your refering?

Thanks
 
Dover, The SB for the 14-13 is #24 from 1948. The hand crank gear is enough different from yours that the only part of the SB that is of note is that you dont want to PRELOAD the two end plates on the retract struts when the gear in extended. On the 14-13 it is done by limiting the jack screw travel, on a hydraulic set up you need to determine the best way to limit the actuator travel so that the two end plates still have a little clearance when the gear is down and under hydraulic pressure. I have never been able to find anything in print that tells what the clearance should be, so I assume 20 or 30 thousands.Thats just a guess. I dont know if your early 14-19 has the same actuators as the 14-19-2, but to make the later model actuators adjustable you can take an even later actuator shaft from a Viking which has a threaded adjustment on the end and put the piston from the 14-19 2 on it ,and create an adjustable 14-19 actuator. You could also have your shaft ends threaded and put the adjustable ends on them. I dont know if I am right or not, but I think that Jonathans gear collapse was from the previous repair that didnt check for this clearance. Some times it is the little things that bite us.______Grant.
 
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