Patching a Perforated Picco

[rctinman]

Long ago, I used to race with K&B 6.5 & 7.5 inboard motors. Needless to say, I had my share of ventilated cases from rods coming through. I always carried J B Weld epoxy with me, and if the hole wasn't too bad, I'd place a piece of packing tape on the inside of the case, and poured J B Weld in the hole from the outside. It worked great, and never had a problem with the J B Weld letting loose.

Recently, I had a chance to purchase a Picco 45 from an IW member that had had a crank let go, and poked 2 holes in the bottom of the case. I bought it mainly for the rest of the good parts, but after I took a look at the case, I thought I'd try and fix it. Here's how I went about it.

Here's pics of the damage before I started work

 

[Al Hobbs]

Please post some pictures when you are done.

 

[rctinman]

I used a Dremel with a carbide burr, and opened up the damage in both spots. I made sure to taper the hole on the inside also to give the epoxy a way to lock in the patch.

 

[rctinman]

The problem with the Picco that I didn't have with the K&Bs, was that the Picco has a deep grove in the inside bottom of the case for rod clearance. With the K&Bs, it was an easy matter of taping the hole from the inside. With the grove in the Picco, getting the tape to stay down in the grove might be a problem. I used a catalyzed silicone mold product called Quick Set, to make a plug in the grove to hold the patch in shape so I wouldn't have to do any clean-up in the grove. The only thing this product sticks to, is itself. The first picture is a shot of the silicone plug, right after I poured it. The second pic. is of the plug after it was cured, and pulled from the engine and trimmed.

Sorry, the pics are reversed.

 

[rctinman]

More to come!

Thanks,

Steve Ball

 

[rctinman]

Now, lets fill the holes. First, I clamped the silicone plug on the inside, at the spot of the bottom most hole. I held the case with a clamp so the hole was as level as possible, so the epoxy will pool evenly. Then, mix enough epoxy to fill the hole. Before I fill the hole, I take a heat gun, and warm up the case so the epoxy will flow nicely. warm the top part of the case, so the heat sticks around the longest. You don't want to heat the epoxy for fear of quick curing it, and loosing strength. As soon as the epoxy hits the warm case, it will pool nicely. I'm showing the pics for this stage for both holes.

 

[rctinman]

Here's what the patch looks like after the epoxy has filled the holes.

 

[rctinman]

Here's what the patch looks like from the inside on both areas. No work needed for either spot on the inside. I will wire brush each area on the inside, to break loose any thin flakes of epoxy that might be around the edge of the hole. I'll wait for a week before I reassemble the engine to give the epoxy a good cure time.

So, there you have it. This is a good way to save a case that may no longer be available, or if you're cheap like me, and don't want to spend the bucks for a new case. LOL

Have a good one!

Steve Ball

 

[David Murany]

Nice Steve. We have actually had them welded up and then refinish the inside of the case after. Beats buying new ones.

 

[Tony Jacuzzi]

that was informative great post Steve

 

[rctinman]

Thanks David and Tony!

Steve

 

[David Bryant]

yes, very well done Steve, thanks

 

[longballlumber]

Good stuff Pops!!! Thanks for taking time to share! As usual, clean and neat.

 

[Terry Keeley]

Good stuff!

 

[Al Hobbs]

Looks really good, thanks for the post and follow ups.

 

[Duck899]

Thanks, thats my old engine, lol

 

[Tom Foley]

Looking good Steve !!

 

[John Beardslee]

We once repaired a full size Mercury stock outboard (Mark 20H) engine crankcase with 5 minute epoxy on Saturday night between a two day race, circa 1960's. A rod bolt came loose and poked a hole in the case and the engine died before exploding. Patch lasted through 3 heats on Sunday, placed 2nd overall. Still a vivid memory. Just don't ask me what I had for dinner last night!!! Thanks Steve, good info and pics for everyone.

John

 

[Stephan Peterson]

Steve were do you get the silicon quick set?

 

[John Beardslee]

Hi Steve,

Alumilite makes one that is used in mold making, not sure what Steve uses but the Alumilite is a good one.

John