Engine Mounts

[Richard Boyer]

This is the 5th year in a row that I have had to replace my engine mount bushings. No chemicals have been used to clean the engine that would deteriorate the rubber.

The edge of the rubber that your can see becomes cracked (severely), in a couple whole sections are coming off. When removed the conical part that is covered looks perfect.

I have been getting the bushings from aircraft spruce part number 22387. Is there a better part??

I have been getting wear on my cowling and my IA thinks it is from the engine sagging. I'm not convinced, but can't argue with the condition of the mount bushings.

I'm getting tired of having to take the engine off every year!!! Any ideas???

Richard

[cvavon]

Re: Engine Mounts

Same thing on a thread on supper cub.org title is c85 motor mount rubbers or something like that same problem on my plane 2 year old same cracks from acs

[Guest]

Re: Engine Mounts

This is the 5th year in a row that I have had to replace my engine mount bushings. No chemicals have been used to clean the engine that would deteriorate the rubber.The edge of the rubber that your can see becomes cracked (severely), in a couple whole sections are coming off. When removed the conical part that is covered looks perfect.

I have been getting the bushings from aircraft spruce part number 22387. Is there a better part??

I have been getting wear on my cowling and my IA thinks it is from the engine sagging. I'm not convinced, but can't argue with the condition of the mount bushings.

I'm getting tired of having to take the engine off every year!!! Any ideas???

Richard

Hi Richard,

I am not being a smart Alek but what chemicals were/are used to clean the engine area?

Maybe they are assumed not to effect rubber but in fact do?

I have experienced similar issues but it was definitely a result of the solvents used.

Dave

[NY86]

Re: Engine Mounts

ECI makes green ones. Not sure if they are any better.

At the risk of insulting someone, is the torque correct?

I had the same problem, but the second time I went to replace them and found the damage to be only cosmetic, I stopped worrying. That was about 10 years ago. Nothing ever separated...

[cvavon]

Re: Engine Mounts

the tork will not cause this as there is a sleeve and it will stop the washers be for it gets to tight the engine is on the rubber and my bolts were 80 in lbs only water under presure

[Richard Boyer]

Re: Engine Mounts

no chemicals at all.

[Pearson]

Re: Engine Mounts

Maybe there are some hot spots comming off your heat shroud, or an exhaust leak, or some other source of heat.

[Hank Jarrett]

Re: Engine Mounts

Might be a stretch, but is there any alcohol in your fuel (auto fuel STC and they aren't telling you the truth about the fuel being alcohol free)? Alcohol can tear the heck out of some types of rubber. Even small spills while refueling or vapors trapped in the cowl could damage the exposed rubber.
The other thing that can damage exposed rubber that way is Ozone. Any electric motors close like an engine heater fan?
I know you said there were no cleaners used but just for info, NEVER use Armor-All on rubber! It has Formaldehyde in it and leaches the plasticizers out of rubber. Makes it really pretty......for a while.
Hank

Yea, I know, this is a REAL stretch.

[Marv]

Re: Engine Mounts

Check to see where these mounts were made. If they are foreign made they are probably junk when new. I removed the hood rubbers from my antique car that was 50 years old because they were deteriating and put new ones on that were made in Argentina, which i would not have boughten if i had known this, but to make a long story short, a year later sitting in a closed gatrage the new rubbers were in worse shape than the 50 year old ones. Marv

[M Towsley]

Re: Engine Mounts

I think Marv is probably onto something. Probably the materials being used, especially if two members bought them from ACS. ACS needs to be informed of this issue, they may already be aware and have different ones now. I would ask for new, I subscribe to the 'You never know unless you ask' way of looking at things. You might be surprised.

[NY86]

Re: Engine Mounts

It's not limited to ACS. The Continental part, regardless of the vendor, has been doing it for about 10 years now. I think it's Ozone, or something similar. That explains why it is only the exposed part that deteriorates. (I think...)

[fearofpavement]

Re: Engine Mounts

Our mount bushings are 17 years old and doing fine. The plane is hangared if that matters.

[NY86]

Re: Engine Mounts

Our mount bushings are 17 years old and doing fine.

Before the fall...