Parilla Swift top end rebuild (JICA)

Walt Gifford · Posted: Fri Mar 30, 2012 9:05 am Post subject:

Sometimes those rods can be polished and re-used with new bearings and pin.

Jim McMahon · Posted: Fri Mar 30, 2012 9:57 am Post subject:

Kirk I think what you are referring to is the bottom rod bearing. "Main" bearing typically refers to the crank support bearings in the crankcase halves.

Hopefully as Walt said the rod is OK, otherwise it will need to replace it. If its blued in any way it will need to be thrown away. At this point you are looking at stripping the crank so unless you have a bore gauge to measure ovalization on the rod, a hydraulic press to strip the crank as well as a surface plate and pair dial gauges to true the crank its time to get an engine builder involved for the crank rebuild part at least. Then you could do the piston and main bearings yourself if you like.
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Kirk Deason · Posted: Fri Mar 30, 2012 9:58 am Post subject:

Here is the best closeup I could get of the piston top. I noticed tiny little pits on the surface, not sure if they are visible in the photo here, they look like pinholes.

Kirk Deason · Posted: Fri Mar 30, 2012 10:01 am Post subject:

Here is my highly technical (yet effective) hairdryer removal method for getting the wristpin out. I heated the piston and then tapped on the wristpin with a drift and it slid out easily.

Kirk Deason · Posted: Fri Mar 30, 2012 10:07 am Post subject:

Rod pictured following piston and wirstpin removal. Beer added for scale and timeframe. Joy at wristpin removal followed by despair of main bearing destruction was less than one beer. Followed by more beers while contemplating next step and staring silently at the bottom end.

Jim Russell, Jr. · Advertiser Joined: 03 Oct 2001 Posts: 1535

The tiny pits are caused by debris getting smashed between the piston and the head. Could be parts of the carbon deposit, bearing parts, sand or dirt from intake, etc.

This engine needs a major overhaul at this point.

More pictures of the lower rod assembly the main bearings in the case would be helpful in determining if these parts need to be changed out also. Most likely they will.

Jim jr.
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Kirk Deason · Posted: Fri Mar 30, 2012 10:09 am Post subject:

Wristpin bearing slides out easily with light finger pressure.

Kirk Deason · Posted: Fri Mar 30, 2012 10:17 am Post subject:

Best closeup I could get of the lower rod bearing. There was WAYYYY too much play in the rod, when I looked closely at the bearing, it was blackened and had obviously failed. The rod does not rotate smoothly around its complete axis. The binding seems to be only related to the bad bearing and not a bent rod.

I wish I could do a .gif to show the range of movement in the rod--it is sad.

Kirk Deason · Posted: Fri Mar 30, 2012 10:27 am Post subject:

Walt Gifford · Posted: Sat Mar 31, 2012 6:14 am Post subject:

This might sound messed up but if you send it out mark the parts you want replaced with a center punch or something that don't come off in a sand blaster. The rod is a high dollar item that can easily be made to look new again, Crank pins can be polished and turned 90 degrees but if you pay for new it should be new. Best thing is to send the whole bottom end so they can set the end play. Can't see those main bearings on return so, split the case, degrease and drop them out with heat at 375.

Gif Cool

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Kirk Deason · Posted: Mon May 14, 2012 11:52 am Post subject:

I finally bit the bullet last week and shipped the motor to Italian Motors in Washington. I think karting is a sport for masochists who enjoy repeated nut kickings. Apparently I am one of these masochists.

Jean Stafford · Posted: Tue May 15, 2012 8:14 am Post subject:

Sado-masochists is more like it, we enjoy self-inflected pain.

I never saw an ICA, or JICA that didn't have a one-race limit.
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Jim McMahon · Posted: Tue May 15, 2012 1:27 pm Post subject:

I've seen plently, just depends how competitive you want to be. If you insist on revving the pi$$ out of it, then yes it wont last long. But what motors are out there that break into the 20K RPM band with "conventional" materials last long anyway?
The JICAs last a lot longer than the ICAs even in competition as they just dont rev as high anyway.
Keep the JICA under 17K RPM, use 8oz of castor/gal and you will get HOURS out of it. Just be sure to inspect and decoke/degum the ring every couple of days.
I'll take a JICA as a reliable play motor with a bit of performance over a KT100 any day.
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Kirk Deason · Posted: Thu Aug 09, 2012 1:43 pm Post subject: Back in business

I've had the motor back for quite a while but kept making excuses about why my kart wasnt runnning. Well, now the chassis has been straightened and that was my last excuse. I fired it up last 2 nights ago, ran it briefly enough to realize the brakes weren't operately effectively. Fixed the brakes (I think), and now can salivate about a track outing on saturday. Here's a pic. I wish I didn't need to put all of that ugly bodywork on it.

Jim McMahon · Posted: Fri Aug 10, 2012 7:31 am Post subject:

Looks awesome, thanks for updating the thread. You'll have a blast with that kart.
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