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Discussion Starter #61
Update on this disaster: Jake Raby got the motor back and took it apart. The rear main bearing and adjacent connecting rod bearing is destroyed. He felt it was caused by a slipping clutch. Will take a lot of money and time to get this fixed. Most likely will source a used motor and give up on the converted motor.
 

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So, a slipping clutch destroyed main and rod bearings? I'm curious what chain of events could have led to that failure mode determination.
I'm really sorry for your loss of time and money, and the ultimate disappointment after such a promising debut. Best of luck going forward.

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Discussion Starter #63
So, a slipping clutch destroyed main and rod bearings? I'm curious what chain of events could have led to that failure mode determination.
I'm really sorry for your loss of time and money, and the ultimate disappointment after such a promising debut. Best of luck going forward.

Sent from my XT1650 using Tapatalk
I know. It sounds weird. Never heard of such a thing. I have heard a few dissenting opinions from other mechanics that contradict this but I am stuck in the middle. Major disappointment. Might just put in a factory 3.8, a proven recipe and be done with it. Will be talking to BGB soon.
 

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Sorry to hear. Guess Raby's not warrantying the engine?
 

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Discussion Starter #66
Jake Raby has been helpful. He is not offering to cover everything for free (the warranty is good for 1 year), but he offered to repair at cost-the problem is this means a replacement case and possible a new crank. It is interesting that they are no longer doing the 4.2 liters-4.0 being the max. I am not entirely convinced the slipping clutch was the problem-it happened after 6 minutes of driving, the clutch wasn't slipping (it was a heavy duty Sachs unit that BGB uses on their conversions). I think the bearing failed/spun and put a ton of heat into the surrounding metal after the failure. I went into this knowing it was science experiment and I assumed the risks.
 

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I hope that you'll be on the road again before too long, and all these troubles will be left far behind you.

Sent from my XT1650 using Tapatalk
 

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not offering to cover everything for free (the warranty is good for 1 year)

My mistake. I had forgotten how long ago this thread had originally started (holy cow, has time passed that quickly??? :oops:). I know there hasn't been that many miles on the engine but didn't realize how many years had passed. I got pinged because I had previously commented on the thread.

Whatever happens, best of luck to you.
 

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Discussion Starter #70
So we are making progress. The 4.2 liter Raby motor spun the rear main bearing. The case was ruined. The custom stroker crank is not useable since after machining the bearing surface my builder can't find a bearing to fit it. We are going back to my original crank shaft and rebuild will be a 3.8 liter. Hopefully a much stronger build than the 4.2. On the car so far is an Ohlin adjustable coil over kit and a Stoptech big brake kit. SPL front and rear control arms are going on the car next. Numeric shifter kit is installed. Counting down the days until I can drive it again.
 

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What a QUEST.

...do you think that the original formula given by the factory, excessively tested and adjusted - is possibly the only way to go, assuming you dont want to experiment?
 
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