Fan of slotted shims for shimming engine?

[Joe Larussa]

So my engine needs shimming. My mechanic started the process but it's not there yet. Still needs to come up and to the left. They removed the shims front the top and put an 1/8" on both lower mounts. One more 1/8" on lower right should do it. A slotted shim would be the easiest way but he's not a fan. Read Maxwells write up on it and seems like I get mixed reactions on this. Paid for six hours already and I don't want to go broke but I want it to look right.

Thoughts?

[Andy95W]

Cutting a slot in the shim will save you about 30 minutes per mount, so if you weigh your options, you're probably still better off letting your mechanic do what he's comfortable with.  I've never noticed a difference that would sway my decision, but I'm not the one signing off the work, either.  

[jetdriven]

I don't see why as the issue.  Slot the shim and drive it in.  Takes all of 15 minutes. It's not a cylinder base nut, the fact 10 degrees of the shim is missing doesn't factor.  

[MB65E]

If he is worried about it coming out...You can cut a diamond shape as the slot, then insert the removed portion back in the diamond cut out area. That way it can't ever back out and there is even torque on the washer/mount assembly. Think of it as a locking key. Did this several times on a 400hp Pitts. Never had a single issue with the shim. I'd loose about zero sleep with it on a 200hp 4 cyl. I can draw it up if he doesn't get it. 

-Matt

[Joe Larussa]

Just now, MB65E said:

If he is worried about it coming out...You can cut a diamond shape as the slot, then insert the removed portion back in the diamond cut out area. That way it can't ever back out and there is even torque on the washer/mount assembly. Think of it as a locking key. Did this several times on a 400hp Pitts. Never had a single issue with the shim. I'd loose about zero sleep with it on a 200hp 4 cyl. I can draw it up if he doesn't get it. 

-Matt

Diamond shape. Interesting! What did you cut it with?

 

[MB65E]

Just with a dermel tool (misspelled in my drawing) cutting wheel, Here's a picture. 

-Matt

[Raptor05121]

Ingenious idea

[Joe Larussa]

8 hours ago, MB65E said:

Just with a dermel tool (misspelled in my drawing) cutting wheel, Here's a picture. 

-Matt

Crazy smart!

[smwash02]

Are you sure it's not your motor mounts?

Not long after purchasing my Mooney my spinner started rubbing on my cowl enclosure! I put in new LORD mounts and that raised it up to spec.

[MB65E]

Thanks, on some installs, the new mounts sag the first 20 hours. But yes, If the mounts are over 5yo, make sure the old ones are not the problem.

One nice thing about the old fish mouth cowl, there is nothing for the spinner to be out of alignment with.  ;-)

Good Luck,

-Matt

[jetdriven]

Even new mounts often need to be shimmed after a few months.  They sag a little after install. Mine did (barry controls).   1/8" on one side and 1/16 on the other.  Since then it's deadass. 

Edited August 17, 2016 by jetdriven

[mooneyflyfast]

Be sure your cowling is not moving up and down.. Lasar makes a kit to reinforce the attachment at the lower rear cowling to firewall to stop this.. My mechanic illustrated this by grabbing my cowling and jerking it up about 1/4 in.. (viewed at spinner to cowl).

Edited August 18, 2016 by mooneyflyfast

[jetdriven]

That kit helps but instead of using the fixed camloc receptacles on the top, make an angle stopper of aluminum and it goes against a fiberglass piece in the cowl.  The screw on the bottom holds it down and the stopper on the top prevents riding up. 

[rbridges]

Mine were slotted 4-5 years ago. Haven't noticed any issues. 

[Joe Larussa]

On August 17, 2016 at 6:14 PM, mooneyflyfast said:

Be sure your cowling is not moving up and down.. Lasar makes a kit to reinforce the attachment at the lower rear cowling to firewall to stop this.. My mechanic illustrated this by grabbing my cowling and jerking it up about 1/4 in.. (viewed at spinner to cowl).

With the top cowl off I have movement in the bottom cowl but soon as I put the top back on it pulls the bottom cowl up. Once all the fasteners are back on you can't move it to save your life. I'm going to attempt adding a slotted shim and see what happens.

[Joe Larussa]

Added the slotted shim yesterday and alignment was perfect. Well then I took it flying and of course the cowl lifted a little in flight. It's better but not perfect. I guess the next move is the Laser solid fastener kit. What a pain in the blank.

[jetdriven]

the kit is nice but it replaces the floating upper camloc receptacles with solid ones.  Then the upper cowl  uses the fastener holes to keep it located, and that wears them out even faster.  

Use the lower nut plate straps but put a piece of glass in the cowl to stop against a small piece of angle aluminum on the boot cowl to keep it aligned.  Leave the floating receptacles. 

Edited August 28, 2016 by jetdriven

[carusoam]

Byron,

are you able to point toward the photographs of the fine cowl work that you did? (Are they in your album?)

Some work done by MSers is very memorable.  

Best regards,

-a-

[Joe Larussa]

7 hours ago, jetdriven said:

the kit is nice but it replaces the floating upper camloc receptacles with solid ones.  Then the upper cowl  uses the fastener holes to keep it located, and that wears them out even faster.  

Use the lower nut plate straps but put a piece of glass in the cowl to stop against a small piece of angle aluminum on the boot cowl to keep it aligned.  Leave the floating receptacles. 

Any chance you have a pic? Having a hard time visualizing this.

Thanks!

[jetdriven]

Lmc