So I need to replace the engine mounts on my Lyc O-360 equipped C170.

The blueprints for the Bush conversion call for Lord J 7402-5 mounts. I called Lord and just confirmed that this is still the mount to use and they said "absolutely".

So I tried to buy some... EXPERIMENTAL AIRCRAFT ONLY is how the product is labeled, and most places no longer cary it.

I called Lord back and they directed me to their two distributors. I contacted one of the distributors via email for a quote and told them what I was going to use the mount for. They emailed back a refusal to quote because that mount is no longer PMA'd for certified aircraft.

I've got another email into Lord (the only people who don't seem to know the mount is no longer PMA'd), but in the mean time I thought I'd see if anyone out here has run into this beforehand.

Thanks.

I thought I heard that the Avcon STC no longer was available. Perhaps the Avcon STC used those bushings, even though they were not pma'd or otherwise approved. In that case, by virtue of the STC, the bushings would become legal on airplanes with that conversion.

If that's the case, the distributors and maybe even the manufacturer aren't aware of the situation, and only assume there is no legal use of these bushings on certificated aircraft.

If you have the STC drawings, take a look at the bushings that are called out there. If those are the bushings, then they are legal on that aircraft by virtue of the approval of the STC. Supplemental Type Certificate.

There are examples of NAPA aviation parts installed on certificated aircraft. No pma, no TSO, just an automotive part. But, because they are on the drawings for that aircraft, they were approved on that aircraft by virtue of that aircraft's TC.

Doesn't mean you can use those parts on another aircraft type, or one that uses a different STC, but......

Unfortunately, or maybe fortunately from what I hear, the owner of the Avcon STC no longer holds the STC. If nothing else, just order the bushings and if anyone asks, tell them it's for an experimental aircraft. Your mechanic should be bright enough to figure it out from there.

MTV

Thanks MTV,

Lord just emailed back and said pretty much the exact same thing. The distributer probably just doesn't understand the STC part.

I'll try again in guise of my alter ego, Hue Jorgan.

So as of now Lord engineering agrees that the STC is all I need, but Lord distribution refuses to allow the dealer to sell me the mounts.

The dealer is talking to engineering in the hopes they'll talk to distribution...sort of funny, sort of not.

Just curious, are these dynafocal mounts? If so, are there that many different ones for a 360 Lycoming?

180Marty wrote:Just curious, are these dynafocal mounts? If so, are there that many different ones for a 360 Lycoming?

Yes, I believe they are dynafocal mounts, and Lord engineering says they are THE mount for the Lyc O-360. "We hang 360's on those day in and day out" is pretty much a direct quote from Lord engineering.

I'm not sure what to make of the whole thing. Obviously that engine is being put in certified airplanes using some sort of mount. Regardless of what other ramifications there might be, my cowling is a very tight fit and I'm loath to start experimenting with engine mounts.

I know that Mooney uses dynafocal with the 360 and I think the old Cherokee with O360 has them. Will look tomorrow to see for sure.

Hammer

Hopefully i will be short with this.
The AVCON got split at a divorce etc. Wife had one STC Husband had another - something like that.
Two phones on the same desk sort of.

I would usually tell you to call Harry Delicker.at DelAir in Porterville Ca. - and warn you to get ready to learn every thing you never knew about planes. But he died sometime back. HOWEVER: Last time I called another Chris - MUCH younger than I, was still there and operating the business. He is a master craftsman.

Any way - Harry had his own version of the "AVCON" STC cause the domestic squabble kept AVCON off line most of the time.

Got a lot of my parts to conver my BUSH system to something closer to his, especially the exhaust system.

Be sure to get the correct amount of large washers under the correct side.
At least for my BUSH STC mount.

Best of luck

Another older Chris C


https://www.google.com/webhp?sourceid=c ... erville+ca

(559) 784-9440

PS: While I have recently moved - and not all unpacked - somewhere I do have a relatively rare FULL set of BUSH drawings and I think a DVD.

Hammer,

I nothing about your situation and what is needed but....

There are many FAA approved STCs (and TCs) that use off the shelf non-PMA parts. A loop hole in the system that is perfectly legal. Your mileage may vary.

Hammer wrote:

180Marty wrote:Just curious, are these dynafocal mounts? If so, are there that many different ones for a 360 Lycoming?

Yes, I believe they are dynafocal mounts, and Lord engineering says they are THE mount for the Lyc O-360. "We hang 360's on those day in and day out" is pretty much a direct quote from Lord engineering.

I'm not sure what to make of the whole thing. Obviously that engine is being put in certified airplanes using some sort of mount. Regardless of what other ramifications there might be, my cowling is a very tight fit and I'm loath to start experimenting with engine mounts.

If they're Avcon, they're not dynafocal mounts.

MTV

MTV

Harry had to do something a bit different - hopefully better - to get his own STC I would imagine.
Might call Chris and ask for sure. (Hammer)

My view of the BUSH one I bought had had a Mooney eng.
I base that on the short canoe paddle blades that went into a "fearther" mode instead of flat pitch.
I did not like hearing the cylinder slap at startup until the oil got up front.

But then what do I know

CC

wannabe wrote:Hammer

Hopefully i will be short with this.
The AVCON got split at a divorce etc. Wife had one STC Husband had another - something like that.
Two phones on the same desk sort of.

I would usually tell you to call Harry Delicker.at DelAir in Porterville Ca. - and warn you to get ready to learn every thing you never knew about planes. But he died sometime back. HOWEVER: Last time I called another Chris - MUCH younger than I, was still there and operating the business. He is a master craftsman.

Any way - Harry had his own version of the "AVCON" STC cause the domestic squabble kept AVCON off line most of the time.

Got a lot of my parts to conver my BUSH system to something closer to his, especially the exhaust system.

Be sure to get the correct amount of large washers under the correct side.
At least for my BUSH STC mount.

Best of luck

Another older Chris C


https://www.google.com/webhp?sourceid=c ... erville+ca

(559) 784-9440

PS: While I have recently moved - and not all unpacked - somewhere I do have a relatively rare FULL set of BUSH drawings and I think a DVD.

Thanks MTV, I'll give him a try.

Interesting what you say about the washers. When we went to try and tighten the top mounts by adding some washers we found that the bolt and nut turned freely under moderate wrench pressure. They were tight, but not tight against the center tube of steel that is part of mount. That the bolts are slightly too long and were just snugged up against the rubber, not the steel tube, is our guess. Lord does not specify a hardware kit other than to say it has to be AN hardware.

Needless to say I'll be replacing all the hardware if I ever get ahold of a set of mounts. My blueprints give a complete list of the required bolts, nuts and washers...be interesting to see if that's what comes out of the old mounts.

Hey Hammer

Might want to be careful who you are giving credit to above!
Personally I take as a compliment that I could never live up to.
But not so sure how MTV will look at it. You might wanna duck behind the couch for a bit.

Be safe

Chris C

Don't know of Spruce is one of the distributors you called, but I just looked in their 2014-2015 catalog and page 386 shows the Lord J7402-5 mounts (p/n 07-02595...$128.75) . The description includes "not FAA PMA approved .....can only be used on experimental aircraft". That said, Spruce has never asked me what a part was going on, or refused to sell me anything.

wannabe wrote:Hey Hammer

Might want to be careful who you are giving credit to above!
Personally I take as a compliment that I could never live up to.
But not so sure how MTV will look at it. You might wanna duck behind the couch for a bit.

Be safe

Chris C

Sorry Chris!

hotrod180 wrote:Don't know of Spruce is one of the distributors you called, but I just looked in their 2014-2015 catalog and page 386 shows the Lord J7402-5 mounts (p/n 07-02595...$128.75) . The description includes "not FAA PMA approved .....can only be used on experimental aircraft". That said, Spruce has never asked me what a part was going on, or refused to sell me anything.

Thanks hotrod,
I did check Spruce, and while they list the part they say they do not stock it and it will take 1~2 weeks to ship. That started me down the rabbit hole of A: trying to figure out why they were not approved for certified aircraft, and B: trying to get them a bit sooner.

My experience with my Avcon conversion has been just as Mike mentioned, where if you did get through, "the other person handles that, he's not here, I'll have him call" and it never happens. However, my IA has become somewhat of an expert on the topic, keeping my airplane going. Granted, Bush and Avcon aren't the same, but he might have some ideas. So I'll PM you with his contact info, and maybe he can help you.

Cary

I don't know who is who here this far down the line. Sure lost my identity recently.
BUT - I have a suggestion .
If you know someone with a Mooney from the time period of your STC, that has a Lyc. 0-360-?!?, ya might ask them about Lord Mnts.

Actually your local Mech. A&P . IA etc should be able to compare #s and order for what ever they go on.

Hopefully

Who ever I am these days.

With the engine mounts all replaced I thought I'd do a summary of the rather baffling process.

GETTING THE MOUNTS
Near as I can tell Lord lost their certification for the J7402-5 mount, which most O-360 engines hang from. This must have been somewhat recent because the box still has the FAA/PMA label.



When I contacted Lord directly and told them what I was using them on (they asked), they refused to sell them to me. Not only would they not sell them to me, but they wouldn't let any of their distributors sell them to me when they recognized my email address or name on the order. Lord's technical staff agree that my Bush Conversion STC is the governing document which gives me authority to use them, as did the distributors, but Lord Distribution refused to sell them to me regardless.

It would appear that most retail outlets don't have them in stock, but order them from Lord as needed. So don't say you're using them on a certified aircraft or you're going to have a bugger of a time getting them. I have no idea why Lord cares what happens to them once they leave the factory, but apparently they do.

I eventually found a place that had them in stock, which is how I got a set. It's easy enough to get them if you don't end up on Lord's no-fly list, but expect at least a week or ten days for delivery.

Barry also makes a set of mounts and they're about $100 cheaper, but the general opinion of mechanics I talked to was that the Lord mounts were probably better. Considering the work involved to swap them out I opted to stick with Lord. Also, that's what was specified on my conversion.

THE SWAP
Once the cowling and assorted scat hoses and wires were removed and the engine hoist was in place, it took a mechanic and his flunky 2.5 hours to change the mounts. The flunky needs to be able to lift about 100 pounds and hold it steady for an extended time, as the engine has to be horsed this way and that to get the bolts out, even with the engine hoist.

Three of my four bolts showed a fair amount of wear. Obviously I bought new hardware for the swap, but I was surprised at the condition of the bolts. I don't know if that's a safety issue or not, but I'm glad to have new bolts for the engine to hang on.



The only reason I addressed the engine mounts in the first place is because the cowling fits very close to the spinner and I could see that the engine was sagging. Not much... maybe a centimeter, but that was enough to start scratching the cowling. My mechanic thought the engine mounts looked fine... no weather checking or deformities. But once we pulled them out it was obvious that they were shot.

I wouldn't have replaced them if the cowling wasn't in danger...never would have even though of it. Lord's technical staff said that at 1000 hours they were past due for replacement, and turns out they were right. Don't know what the ramifications are for running with worn out mounts.

Hammer,

I'm betting that Lord wouldn't sell them to you for a certified airplane for fear of being sued. Even though you TOLD them you had an STC that "legalized" them, they probably figured they still had exposure.

Glad you got it figured out in any case, and, yes, I suspect engine mount bushings are one of the most neglected parts on an airplane. And they do a tough job in an ugly environment.

MTV

Hey Hammer Glad you got that sorted out, care to send me a pm of who you wound up getting the mounts from? I have the Avcon 170 and although my mounts are still "ok" Im thinking in a year or so they are going to need to be replaced. Looking into the future I see trouble coming my way on getting new lord mounts......or possibly the new owner may see trouble.....Thanks! Greg