Installing a lifting point

[mhorowit]

Although I asked the mechanic to install a lifting point when the engine was o/h, he didn't do it. I"ll ask him to mail me the lifting point and plan on installing it myself. Question: this will involving removing two bolts which hold the engine halves togeher. I plan on measuring the torque when removing the bolts and re-torqing them with the lifting point in place. It's that simple, right? I mean there wasn't a sequence of tightening that I'm screwing up was there? Won't have a problem with the bolts being too short now that the lifting point is in place? - Mike (who worries too much)

[Hank Jarrett]

Re: Installing a lifting point

DON'T retorque to the break-away torque to remove the bolts! That will NOT be the correct torque to tighten to. I don't have a manual here for the correct torque but I am sure someone will chime in.
To do it right just put the two bolts in to about 1 or 2# UNDER the required torque and then run around the whole set of case peremetrer bolts and click them up to the required torque in order. I would be amazed if at least a couple (other than the two new ones) aren't a couple of pounds short of spec. After you run a newly overhauled engine a few hours you should go over all the bolts and check torque. Lots of times the warm up and cool down cycle lets some of the bolts "seat in" and show low torque.
Don't forget that when you put the lift lug on the bolts may need to go up a grip (unless your IA was nice and put an extra washer on).
Hank J

[mhorowit]

Re: Installing a lifting point

Hank -Here's the key phrase "around the whole set of case peremetrer bolts and click them up to the required torque in order." - which answers the question "can I get away with simply removing the two mounting bolts, adding the lifting point and replacing the bolts (assuming correct length) with the correct torque?" The answer is "no, there is a sequence of tightening, just like you do with and engine head cylinder to avoid warping". So I need the sequence and torque. . - Mike

[Hank Jarrett]

Re: Installing a lifting point

Mike,
Send me an email at home and I will pull the overhaul manual. I can probably come up with a number system so you can tell which bolt we are talking about and give you the order that way. If not I will just Xerox the page and mail it to you.
Hank
[email protected]

[mhorowit]

Re: Installing a lifting point

Hank - thanks for the offer; however, since I'm going to drop by to pick up the lifting point (and perhaps the bolts), I"ll ask the A&P for the correct torque, sequence, and how to proceed; that makes it easier for all concerned. - Mike

[Garry Crookham]

Re: Installing a lifting point

Mike:
Don't know if you found the answer to your questions about installing the lifting eye:
On the A65/A75 engines, the bolts used to install the lifting eye are 1 5/8 in long (p/n 24878) vs the other 10 case bolts which are 1 1/4 in long (p/n 24251). There are also 3 dowel bolts installed which align the case halves.
The bolts are torqued to 100-125 in/lbs. On the 4 cylinder Continental engines, no sequence is specified for tightening the case bolts. The 6 cylinder engines do have a specific tightening sequence.
Teledyne Continental's website www.tcmlink.com has some good info concerning this: SB96-7C Torque limits.
Hope this helps.

Garry Crookham
N5112M
Tulsa

[mhorowit]

Re: Installing a lifting point

Here's the result of talking with the engine mechanic.
He said "use the german measurement "Gutentight". So much for my expensive torque wrench. I got the impression even if he were tightening down the complete case, his advice would be "snug all the way around, try to make it even, this isn't rocket science" - none the less, I'd probably tighten down bolts in sequence that were opposite each other (same as tightening down a car wheel. - Mike

[Hank Jarrett]

Re: Installing a lifting point

When I majored the 65 for mine the IA working with me was very emphatic about the tightening torque and order. We went back and forth, top and bottom (a lot like tightening a wheel) and we snugged them to a couple of pounds below an ultimate value he (I thought) got from the "book". Once we could go all the way around at that torque we criss crossed to the final torque. He was pretty serious about how important it was to get them tightened evenly but I have to admit I was the one with the greasy hands and I didn't actually look at the book he was holding. He also wanted me to be sure I re-torqued them after the engine had run for 10 or 15 hours. He didn't act like this was an "option".
Hank

[mhorowit]

Re: Installing a lifting point

Hank - My A&P advised he's taking tomorrow off, so I can't work on the beast tomorrow. I had planned on building a make-shift engine stand, lifting the engine off the tire and onto the stand, but I guess I'm left to dream for another week.

What I planned on doing was mounting a 2x8 in place of the prop and bolting that 2x8 onto a pair of 4x4's(laying parallel, on the floor, 4 ft. apart). Visually the physics look OK and it won't tip over while I apply the lifting point, exhaust, etc.

The big accomplishment for tomorrow was to make a template of the flange so I could replicate the holes in that 2x8, but with the shop closed, I can't do that. Do you have any idea where I could find (on the Internet) the dimensions/positions of those holes? I'm not sure... is the flange flat to the prop or were there some sort of 'bumps' that fit into the prop?

- Mike

[Hank Jarrett]

Re: Installing a lifting point

I'm a little worried about the idea of using 2x?s for an engine holder. The one replacing the prop will be bolted (I assume) to the other two and there will be quite a stress between them and the "prop". If I am imaging this right you are talking about something that looks like an "H" on the floor with the engine (shaft down) at the center of the cross bar. The stress at the "H" sides where they meet the cross bar could be too much for the bolts.
The best designs I have seen use a bent prop hub (lots of them around, they don't straighten worth a hoot, not the prop, the hub it mounts on that goes on the shaft of the engine). You weld that to a pipe and the pipe to a BIG car wheel or plate with some triangle stiffeners. All you do is stick the end of the crank shaft in the hub and work away on the engine.
Make SURE you lube the end of the crank so you can get it out again!
Hank

[Howard Wilson]

Re: Installing a lifting point

Mike, Can't you just bolt up the exhaust with the engine lying upside down on the tire, then when you are ready get a couple of guys to pick it up, flip it and hold it while you put the bolts in???? Should only take about 10 minutes to hang it. Maybe use the butt guys from hanging the wing;-)

[mhorowit]

Re: Installing a lifting point

Hi Howard - the butt guys are drinking beer and playing games with a cigarette lighter.

No - most of my work is done alone, in the dark, off in the corner, I'm going at my pace, so I gotta mount the eng. somehow.

I spent the complete day ignoring a guest lecturer, dreaming about my makeshift engine stand and Hank has to go and make a valid point.

Well, now I got a week before I can go out, so I'll re-look some of the previous suggestions. - Mike

[Garry Crookham]

Re: Installing a lifting point

Mike:
I don't know if you engine has a flanged or tapered crank. If it's a flanged shaft, the flange (per the type certificate data--available on the FAA website) is 5 1/2 " in dia with 6 equally spaced holes (.621 dia) on a 4.375" bolt circle.
If your engine has a tapered crankshaft, it is an SAE 0 taper...you will need a prop hub to bolt to your proposed engine stand.
Places like Wholesale Tool Supply or Harbor Freight sell inexpensive steel stands made for power tools....you could probably find one of these that would be suitable....just drill the top to fit your crankshaft (or prop hub).
Would be happy to loan you an engine stand if you want to come to Tulsa .

Garry Crookham
N5112M
Tulsa

[mulwyk]

Re: Installing a lifting point

I received the zero time SMOH engine for my project upside down in a tire. First I lifted it off the tire with a come-along winch ($20 or so at the farm store, they called it a "calf puller") attached to a 2X4 between the rafters of my garage/shop. I left it hanging on the calf puller while I removed the rotten carb and defective magnetos. But when I discovered that my zero time engine needed to have 2 cylinders removed and repaired, I wanted a more solid support.
So next I bolted the engine back to its engine mount using the same rubber cones and bolts that came with the airplane. I bolted the Mount to 2 2X8's each about 6 feet long. Then I screwed the 2X8's to the wall of my garage/shop. I used 1/4 inch lag screws, 8 of them screwed into the wall studs.
The resultant engine "stand" is solid as a rock and is great for working on all sides, top and bottom. A little snug in back, but no problem. I ended up doing a complete top overhaul, paint, baffels, accessories, everything but splitting the case, all on my $2 scrap lumber off-the-wall engine stand. When I'm ready I'll just hook up the calf puller again, unbolt the mount from the 2X8's on the wall, swing the whole engine 180 degrees and bolt it to the fuselage.
Bob Gustafson

[mhorowit]

Re: Installing a lifting point

Bob - I like your thinking! Half the fun in working with these a/c is figuring out how you're going to do something - Mike