• Welcome aboard HomebuiltAirplanes.com, your destination for connecting with a thriving community of more than 10,000 active members, all passionate about home-built aviation. Dive into our comprehensive repository of knowledge, exchange technical insights, arrange get-togethers, and trade aircrafts/parts with like-minded enthusiasts. Unearth a wide-ranging collection of general and kit plane aviation subjects, enriched with engaging imagery, in-depth technical manuals, and rare archives.

    For a nominal fee of $99.99/year or $12.99/month, you can immerse yourself in this dynamic community and unparalleled treasure-trove of aviation knowledge.

    Embark on your journey now!

    Click Here to Become a Premium Member and Experience Homebuilt Airplanes to the Fullest!

AutoPRSUs engine discussion

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

pfarber

Well-Known Member
Joined
Feb 21, 2019
Messages
1,064
Location
Dollywood
They mainly sell a $15k PSRU but also offer a FWF package in the $40k range



I'm surprised to see many of the same faults. I'll time code the video since it jumps around

On the clutch at 7:56 the bolts are flush with the nuts, not locking mechanism visible. None of the nuts/bolts appear to have locking mechanisms

At 8:22 he talks about the starter size. Um... geared starters are a thing. OK, not a real issue but 'salesmanship'??

0:48 at the bottom there is a container (yellow) with a hose. Hose not secured with a clamp.

0:57 white K&N filter (for PSRU? Engine?) not lock wired, nor does there appear to be a method to wire it.

Overall no safety wires. Most of the bolts appear to be the proper length, but I see some lock washers against aluminum. They need a steel washer under them. Note that the prop governer IS PROPERLY LOCK WIRED. Most likely because its a certified unit and its required. But the rest of the $40k motor? NOPE. One one piece of lock wire anywhere. This is a HUUUUGGGEEE tell for me. They bolt a certified part to the E/AB motor and INSTANTLY you can tell that its done to a much higher standard.

BBUUUTTTT at 2:27 they show a close up of the governer. You can see the actuation cable..they went with a jamb nut. HARD FAIL. Read AC 20-71:

6. DUAL LOCKING DEVICE. A dual locking device on a fastener consists of any two separate locking features described in paragraph 5. (note jamb nuts are not listed)

7. BOLTS SUBJECT TO ROTATION. A bolt is considered to be subject to rotation ·if it serves as an axis of rotation producing relative motion between the bolt and one or more components attached to the bolt.

e. Bolts which are subject to rotation must have at least one nonfriction-type lock. The other lock, if dual locks are required, may be either a friction or nonfriction-type lock.

If they replaced one of the jamb nuts with a self locking nut (a $.15 part) they are golden.

3:22 The upper radiator hose. I get that they don't have a molded custom hose, but that splice in the middle with hose clamps... who wants to bet that the metal insert is not properly beaded for hose retention?

3:24 on the firewall, there is a hose fitting that bothers me (its red and blue) on the firewall.. but its probably for the test stand.. but still... its a tell that they are not thinking up to certified AC standards.

I did like that they went to with AN fittings for hoses and cable clamps were properly insulated. These two items, out of a $40k motor are the only aircraft level of build I can see. And if they charge $15k for the gearbox, that's a $25k motor (lol really? For an LS3?.. sorry, I digress) without any of the proven techniques of airplane maintenance/construction.

Again, I have NOTHING against AutoPSRUs, I'm just looking for 'best practices' from companies with products out there to compare them against certified engine best practices.
 
Back
Top