wear issue on L/S RR oil cooler baffle panel

[JCN247DE]

Group,

Thought I would pass on my recently found wear issue on the left side rear baffle panel. CB6-5-360 is Van's part number. This is the panel that the oil cooler is assembled to for behind #4 cylinder positioning. This is an area not easily seen during visual checks of the engine compartment.

http://img409.imageshack.us/img409/6674/lsrrbaffye7.jpg

http://img409.imageshack.us/my.php?image=lsrrbaffye7.jpg

The lower wrap around portion that contours the outer #4 cylinder cooling fins is nearly worn through in several of the grooves shown.

There are just shy of 400 hrs on the set up at this point. O360 bart engine with balanced Superior parts and dynamic balanced Hartzell prop (for everyone that is going to say there is excessive vibration). Neither the cooler or hoses contact the engine mount at any point as well. The oil cooler assembly is braced well beyond the plans and you cannot move the assembly up and down, side to side, etc.

When the new parts go back on I will be securing the under cylinder safety wire that holds front and back baffling together even tighter. I suspect this is the culprit.

Any other suggestions from those who have experienced this?

Thanks,

Jeff -7A flying since Nov 05, getting close to 400 hrs.

 

[az_gila]

Two items...

Two items.. directly from my Tiger experience.

1. Use a spring instead of twisted safety wire. Use two short springs from each "baffle wrap" to the central inter-cylinder baffle piece. Reinforce the spring mounting hole at each end. Some folks use a pop rivet with the "pin" popped out.

2. Use a small strip of high temp. red RTV as a "rub strip" across the baffle piece. Let the strip completely harden before assembly. You can see from your wear pattern where the strips should go...

...hope this helps... gil A

PS .. the above came from one of the Grumman engine baffle experts who rebuilt my Tiger baffles...

 

[JCN247DE]

Thanks Gil

Gil,

Very helpful info and I appreciate it! I looked at my cylinder fin profile and will need to bend the wrap tabs on the baffles more aggressively to conform to the radius. It seems that just tightening the "pull together" underneath will cause them to conform to the cylinder, but it still places the majority of stress on the area in the preceeding photo.

Maybe this will allow a more even distribution of pressure the next go around. When I was at this point with the baffles originally, I was just elated to be finished and didn't really look at this contour area.

Hopefully this helps those in the baffle phase....

Jeff