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Messages - maxwells-demon

#1
Turning Wrenches / Cylinder Rebore - Who does this work?
September 03, 2022, 10:59:55 PM
I've got a set of Daytona cylinders that need to be rebored.  Anyone have recommendations for someone who could do this work?
#2
Turning Wrenches / Daytona Engine Rebuild
September 02, 2022, 04:24:44 PM
The background on this project is that I bought this Daytona from the original owner's son with 5000 miles on the odometer.  It was ridden occasionally until the late 80s when it was parked in a warehouse where it stayed until I bought it.  The son thought that it had been parked due to his fathers age and not because there was anything wrong with it, but could not confirm.  Based on that information, I decided to clean it up and fix only the parts that obviously needed fixing before trying to start it up.  I rebuilt the carbs, replaced the head/exhaust/cover gaskets, and replaced all the rubber parts (intake manifolds, tires, air box pipes, etc.) as they were crumbling.  I did not pull the cylinders or split the cases at this point, but did a leak down to verify the engine was still sealed.  When I got it all put back together, it started up fine, would idle stably and rev out on the center stand.  When I tried to take a lap around the block, I found that it wouldn't take throttle under load...i.e. I could putt around the block, but not under any significant power...the engine would stumble and fall on its face if you applied much throttle.  Sooo...I decided to do a complete tear down on the engine.  The pictures below are what I found.  Substantial blow by is evident on the pistons, which is strange because it passed compression testing.  I measured the ring gap and they were symmetrical...top ring on both cylinders was at 0.0350" and second ring on both was 0.030"...WAY above spec.  Interested in your assessment on what needs to be replaced.  I'm assuming new pistons and bore are in order...should I rebuild the crank too?  Is it safe to assume that whatever caused accelerated wear in the cylinder also wore the bearings?  Is there a way to check the crank/rod bearing health?  Any thoughts or recommendations are welcome.

Also...the pistons look to be different.  As far as I know, no one has been inside the engine...would it have come from the factory with different markings between the pistons?

Chris

#3
Looking inside the lens...maybe this was bonded to the red transparent plastic, but became unbonded at some point in its life?
#4
Cleaning up the tail light on my Daytona...opened it up to find this part inside the lens.  Obviously it was sitting against the bulbs and melted pretty bad.  Looked on the parts fiche but couldn't find it as a stock part of the tail light assembly.  Thoughts from the group?  Was this a stock part, or something the PO installed for unknown reasons?