I have a problem with a P7-R and was wondering if anyone can help.

When I first bought the engine brand new I went through the typical break in cycles. Around the fifth or sixth tank I noticed that the crankshaft was hard to turn when the piston was all the way down. So I took the back plate off and noticed it was rubbing quit a bit, so I sent it in for warranty repair. I know it may rub a little, but this was excessive rubbing, so much it become almost impossible to move the crankshaft at all.

They went ahead and replaced the crankshaft and sent it back to me.

Now I got it back, and all looked good, was spinning with no rubbing when the piston was at the bottom. But now it is rubbing again after about 6 tanks.....

I have checked the clutch bell nut, I have tried to make sure the crankshaft is pushed forward as much as possible, but those do not seem to be the problem.

Anyone have any idea what could be causing the crankshaft to shift rearward far enough to make the con rod pin rub the rear plate?

Yo G,
Julio and Dave had the same problem with your Picco's twin brother the Mega ZX21. They sent them back got em warrantied and they are just now sitting in a box waiting to be sold. Next time stick to Novarossi [:-]

BTW- If your looking for a good deal on a P5T Rex my buddy at Extreme has the Ghetto LOW on them right now. PDL style. Call me you got my number.

flywheel nut u not tite enuogh not picco problem it you problem[:'(]

qwertydvorak,

I meant to say flywheel nut, called it a clutch bell nut by mistake..



I have recently read on another forum that Picco is having an issue with the crank pins walking out of the crankshaft.

ok i understand now my friend that no good then

also every engine rub about 0.01mm you can see the rod scratch a bit i fix on all my engine by dremel 0.05mm on the backplate i never have and mark on the rod after i do that

aopparently the US spec P7-R has a different crank now that has a hardened big end pin pressed into the crankshaft! this was done to enable a harder more wear resistant material to be used for the big end pin while not having a complete crankshaft that had been over hardened & become brittle
it sounds like your pin has worked its way out a little, unfortunately this has happened on a few engines[&o]

adam knows what he's talkin about!!! Thats why he said a few months back that his "RB's scream louder than yo mommma" Novarossi all the way, Call Thomas MNassari at Extreme!!!

Yep that should be it. The best solution is to try and get hold of an original P7-R OFF-ROAD crank. But if you've rad the instructions to start with you'd have seen that this mill only needs 15 minutes of breaking in. The hardened pins have become known to loosen when the engines are run in for too long at a rich seting. The extra stess from trying to compress the denser mixture in the chamber then the crankcase just hammers the Big end pin and that will loosen it allowing the scoring of the back plate. This will cause swarf to fall off and enter the bearing and also g throung the chamber, both wearing away the bearing and the liner face. Basically you broke the engine in for too long.

Well thats put me off buying one

What they are one of the best on the market, just follow the run-in guide in the manual and they dont break.

You havent had any problems with yours then?

Not one problem with either of them, New plug every gallon and ARO every day their run and they are sweet. They are though the original P7-Rs with the single piece crank so that might explain why. Also they have done 20 Imp gals between them now and still no drop in performance. These mills just dont seem to be phased by anything.

Is there a way to know if its a original or not without taking it apart? I dont think my LHS would like that to much

Uberchav Alex,

I followed the instructions to a T, and when I got it back from warranty repair and it was already broke in, and then it broke again.

So not sure it's my fault like you state, I pretty much think it's a manufacture defect and no fault of my own.

And I had it running perfect, SKYLINE350GT actually drove, I’m sure he will attest it was not running too rich.

I know you like this engine and praise it often, but personally I’ll never buy another Picco again.

No you nver, you admitted that in your first post, you ran it rich for 6 tanks, way too long. If they only replaced the crank then the damaged rod would have remined thus hammering the new crank pin the hell and once more back to the same problem. Your engine needs a new crank, rod, back plate, piston and liner. Nothing less than this will fix it.

I forgot to mention IMO the second occurance was not your fault if it was only the crank that was replaced, so I believe the warranty is still valid. Send it back and tell em it's the second time.

I would think it be better off buying a new engine, them parts will be close to the price of a new one.

I think we have established the problem is with the 2 piece cranks, and Alex has a one piece crank...

Therfore you are gonna have different results...

Why they couldnt just harden the crankpin like most of the other motors I have no idea...

[X(]

But they screwed up the first time they warrantied it. So You should ask for a new one or whatever your local Law allows.

I drove netmasters car- That sucker was not running to rich at all. Had gobs of power. Made my Collari 7 port look like a dog. As for me. I'm going back to Novarossi based motors and Novarossi motors alone. Nothing less will keep me happy.

Netmaster- call Thomas man. He's got the stuff to cure your itch!

found an intersting post from a Picco supplier in the US

sounds like he thinks there's definately a problem[:-]

glad mine is one of the early 1 piece crank versions

Hey I have a Picco P7-R and i had that problem with the engine not starting. I was going to get rid of it. But i decided to send it away. I got it back and they said that there was nothing wrong with it. But ever since then it has been going and starting the best. I run it with a small carb restricter, i dont know wat size. But just keep at it and it will eventually come.[sm=thumbup.gif]

Sky, thanks for the tip. I got with Thomas and he hooked me up with a P5. Great guy and great deal