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« Last post by Jeff XL79 on February 17, 2025, 02:23:10 PM »
I've checked the fundamentals and believe that the issue was the huge carbs on a better half. The vm 26 carbs are on the way.
Like I said in my previous post the original builder went along the general guidelines for construction of the better half version of the engine . He must have made the error in carb selection based upon an article Leonard wrote describing the build process. Leonard references a 32mm Mikuni for use on the better half. What wasn't clear was the 32mm was for single carb use . The vm26 is the actual recommendation for dual carb use. Everything else on the engine looks correct. I don't know the compression because I don't have a gauge that fits.
Jeff
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« Last post by Jaggedscars on February 17, 2025, 11:29:26 AM »
Hello. Is there more history you can provide on the XL and engine you bought? Dual Mikunki's shouldn't be an issue if they are jetted appropriately, but your statement on 'run on choke' leads me to believe that there is a lean condition. Has the engine sat for quite some time? Could the carburetors need cleaned rather than replaced? Have you checked the compression and if so what were the numbers for each cylinder?
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« Last post by Tom H on February 17, 2025, 06:29:06 AM »
On the Treehugger mount as seen in the photos above, we used a combination of 1/2" and 5/8" od 4130 tubing. Thickness was either 0.035" or 0.049", maybe a combination of both - can't remember.
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« Last post by Jeff XL79 on February 16, 2025, 08:56:51 PM »
I think that I found the issue. The original builder used dual 32mm mikunis where Leonard had used one 32mm with a dual intake manifold. There is no way dual 32's would have worked. I'm going to try dual vm26 carbs.
Jeff
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« Last post by Jeff XL79 on February 16, 2025, 02:41:34 PM »
I'm trying to sort out the engine that came with this xl I bought. I got it to run on one cylinder with the choke on. I've checked all of the simple things like float level. I measured the engine side of this mikuni and it's 32mm. Isn't that rather large for a 30 hp engine. I thought this size used a vm26 . What the heck?
Jeff
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« Last post by Dan_ on February 16, 2025, 12:40:03 PM »
Maybe you could do an actual compression test on both cylinders... But they should feel the same doing the "armstrong" compression check propping it.
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« Last post by Brock on February 16, 2025, 08:43:48 AM »
Reviving an old thread for a quick question.
What diameter and thickness of tubing have folks been succeeding with on the Verner engine mount?
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« Last post by Kamcoman77 on February 16, 2025, 07:44:43 AM »
Camshaft turns at half speed of crank. Cam gear twice as large as crank gear. Turn crank twice, camshaft turns once.
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« Last post by Jeff XL79 on February 16, 2025, 06:52:01 AM »
I will check both suggestions. Thank you.
I was able to see the timing marks using a mirror and my cheap endoscope. The marks line up every two rotations. I'm baffled but there has to be a reason that's fairly simple.
Update: when #2 is at tdc the valve gap is 6 thousands. I'll check the mushrooms next.
Jeff
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Eight or nine years ago I had a bent valve lifter push rod that was due to bad heat treating or lack of heat treating. It would run on only one cylinder.
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