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I find it odd that two cranks fail in the same boat. I have used picco 45 engines for years and only ever had one fail like this one. And these were the smaller 7mm cranks. Something else is going on. Not trying to stand up for picco but this seems very strange to me. Is it possible to get pictures of the set up??
 
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Norm possibly too much power :lol: Brian it was the fifth tank on this motor and I will get this shot and post it .I'm with Jim and Tom as only Picco's presented failures.If someone want to see the set up in the Jae go to my website www.grsboats.com.br .The Jae in that article is equipped with and old black head(2000) that is running strong till now.....only the new motors failed in different areas of the crankshaft.Nitrosnifer I'was a Picco dealer since its first release in 1979 untill 2000 when they started to mess with the exr series .....a complete disaster that ended with marine production until they announce they were back.with the 45.Anyway I stuck to CMB and will see how the new Nova performs..hopefully we have good options.Tim K the flex collet is ok as all my collets are checked on my lathe for possible misaligments..Georgia I'm quite impressed with the Jae's Fe running here(up to 80mph) so this is another possibility even with no smoke or noise :p
 
I really don't know what is happening with Picco's engines but in less than a month a second failure....maybe someone has a clue.Motor mounted in a Jae fuel Wildcat 35% nitro 18% oil during break in.
Gil,

Measure that crank diameter at the small end, something dosent look right, it almost looks like a older 7mm crank, which wont work in a 2000-2011 case.

The threads look fine - 1/4-28 on your crank
 
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Would be interesting to know what the material is.

Anyone have the ability to have it analyzed?

What about Rockwell testing the break for hardness?

Had this happen once in a 45 disk motor after many gallons, looked like it cracked a bit before it finally broke. Metal fatigue can be hard to analyze... :unsure:
 
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Would be interesting to know what the material is.

Anyone have the ability to have it analyzed?

What about Rockwell testing the break for hardness?

Had this happen once in a 45 disk motor after many gallons, looked like it cracked a bit before it finally broke. Metal fatigue can be hard to track down... :unsure:
Can't Rockwell a surface that is not smooth on the top & bottom. Round shapes will have a correction factor. Also care must be used when testing something that is surface hardened.

Jim Allen
 
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um...in my case..

after awhile, i could tell which cranks were heat treated by sight...

the cranks that were breaking had a new/raw finish to the metal, whereas the "good/hardened" cranks had an uneven dark brownish finish on the non machined portions of the crank
 
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Joe you are right and sorry for the wrong piece....this is .the right crankshaft.Actually we had three failures in the last 5 months with Picco engines...the 7mm crank was of a Blue head. that failed in the end of last year after many many galloons ....something acceptable and part of this hobby.Anyway I'm glad with my Mac's ,CMB's and Nova's running great with no issues.

Gill
 
I spent an afternoon with Alberto Picco at their factory. My impression is that they are a good manufacturer, using good materials and wanting to provide a quality product for the price. I got the opinion that if they had a problem, they want to hear about it.

In my opinion, they would appreciate learning about your trouble so they could check to see what might be the cause. I also think that they would be happy to tell you the material used in their cranks.

I am sorry that you had this problem, but it can happen with any manufactured items.

As for the A/A engines, I will save any parts failures to take with me to Italy and show to the Rossi family. Failures need to be identified and inspected by the manufacturer so that any problems can be corrected.

Just my opinion,

Al Hobbs
 
Hi Al thanks for your input and yes I 've sent two or three e-mails to them but had no luck with answers.In 1982 during a trip to Europe I visited the factory ,at that time in Monza, and was quite imptressed with the treatment they gave to us,reason I became a Picco fan but in the begining of 2000's with the constant changes in their line of motors even spare parts I decided to stop the local distribution.After asked these unhappy owners I will send the parts to the factory and see what happens...at least a decent feedback is waited..

Thanks

Gill
 
I agree, constant changes are a pain.

Hopefully you will get a complete and timely response.

Al Hobbs
 
Gil,

My guess as a toolmaker, would be that there was way to much torque applied to tighten the flex collet to the engine. And the steel is on the britle side of it's hardness range. But that is just a guess.
 
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Just to get you all informed that a new crankshaft is going from Italy to downsouth for free.I couldn't have the second one sent to the factory due to customer's decision ....anyway I'm happy with the final of this story.

Gill
 
All the manufacures have periodic times of crank failures. I even remeber when Novarossi went through a rash of failures. Sometimes it's because the hardening process goes one point above the upper end of the "envelope" making the steel too brittle. Sometimes the steel composition is not within the "envelope". Not every batch of XXXX steel comes out of the mill with the exact same properties. Now if everything was "military spec" than we wouldn't have these faliures, but then an engine would be $5000, not $500. And yes there are stronger steels and more precision processes, but most r/c boaters do not have access to a $$PrintingPress$$.

Jim Allen has some pretty bullet proof engines, but he'll be the first to tell you that each one is a $10,000 bill.
 
I broke more picco parts in a 2 year period, then in my 19years of model boating...

broke a crank one day, went home put a new crank in next time at the lake BOOM there go's another crank.. :(

you soon get over it, was not even about the $'s as most of my picco parts etc where given to me...

but as we all know. NO ENGINE IS BULLET PROOF!!!! ;)
 
Don't even get me started on the CMB 1.01 pistons breaking. not the hole melting deal but snapping in half thing.

2 in a row now.

You find out real quick where the weak link is when you push the limits.

David
 
Don't even get me started on the CMB 1.01 pistons breaking. not the hole melting deal but snapping in half thing.

2 in a row now.

You find out real quick where the weak link is when you push the limits.

David
David, any pics of the pistons? I havent seen that before, I have melted pistons, broken a crank pin, killed a few bearings, had carbs break, but not pistons!
 
I think it is possible to greatly improve the realibility of present day manufactured engines without a large increase in the engines cost. It seems that the things that fail the most are, the piston, the connecting rod assembly & the crankshaft, especially in larger size engines. When adding up the cost of these replacements parts, wouldn't it be better to pay more up front.

The best material available for pistons is RSA-444 T6, 30% silicon aluminum. The best material for the connecting rod is AISI S-7 tool steel. The connecting rod needs a caged roller assembly. The best material for the cage is C-350 maraging steel. Rollers & crank pins can be made of M-2 steel. The crankshaft's best material is AISI S-7 with a seperate pressed in M-2 steel crank pin.

There are steel alloys & aluminums available, that would make possible, a "bullet proof engine".

Jim Allen
 
Over the years, I had many discussions with John Brodbeck. On one such occasion, I told John that if K&B would just come out with a high quality engine, almost every boater in North America would run it instead of Italian and Japanese produced engines.

John told me that 80% of the engines K&B produced were never started. They were gifts to fathers, sons, brothers and friends. Then, these engines ended up in a closet somewhere and were never used. The reason that he sold so many engines is that he kept the prices as low as possible which meant he had to keep his costs as low as possible.

He said it was no problem to replace broken parts for the 20% of the engines that were actually run, because he kept his costs so low to sell the other 80%.

I do think that it is a natural decision for any manufacturer to save on any and all production costs, wherever possible. The only model engine manufacturer that I think did not follow this pattern was Gennadi Kalistratov and while he made great engines, they never became as popular as the lower priced engines.

So, if a manufacturer can save 5 cents on a part, his inclination is to make the savings.

I really appreciate Jim's suggestions as to what materials to use for the various parts. And the aditional costs involved for a run of 100 to 200 engines surely would not make that big a cost increase. But getting a manufacturer to just make a seperate run, using the better materials would be a noticealbe expense.

Al Hobbs
 

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