Author Topic: 230sl crank issues ac??  (Read 1261 times)

Ahealey12

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  • USA, TX, San Antonio
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230sl crank issues ac??
« on: August 16, 2024, 04:35:47 »
I’m not finding very many posts about a crank breaking just seeing posts that it is common on a 230sl when added stress with air conditioning. Is this still an issue with the buds Benz kits with updated compressors? I’m daily driving this in San Antonio and am pretty interested in getting ac but also don’t want to destroy my engine just to have ac.
1967 230sl auto
1967 Chevelle ls swap
1968 bronco ls swap project
2022 zl1 Camaro
2021 Range Rover velar daily family car

ja17

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Re: 230sl crank issues ac??
« Reply #1 on: August 16, 2024, 14:24:43 »
The newer style rotary compressors are much kinder to the crankshaft with less vibration and drag. The problem is often caused by the installer not performing the specified torque on the crankshaft bolt. Eventually the crankshaft pulley assembly and vibration dampener become loose and ruin the end of the crankshaft. You must be certain that the bolt is torqued to specs. In addition the Factory manual describes an upgrade procedure that can be performed using an improved stretch bolt, and three heavy belden washers along with larger dampener pins which greatly strengthen the assembly. The set-ups with the newer compressor may not need the upgrade as long as the crankshaft end is in good shape and the bolt is torqued correctly. Your engine might already have the improved stretch bolt and washers. A different torque procedure is used with the stretch bolt assembly (described in the BBB). Just having the new stretch bolt assembly greatly improves the set-up even if you do not perform the difficult procedure to install larger pins. After the 230SL the pagoda engines did not have this issue. The pulley/dampener/hardware assembly was improved.
« Last Edit: August 16, 2024, 14:31:30 by ja17 »
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

Ahealey12

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Re: 230sl crank issues ac??
« Reply #2 on: August 17, 2024, 02:03:24 »
Awesome thank you Joe!!
1967 230sl auto
1967 Chevelle ls swap
1968 bronco ls swap project
2022 zl1 Camaro
2021 Range Rover velar daily family car

Lenosa

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Re: 230sl crank issues ac??
« Reply #3 on: September 12, 2024, 16:53:56 »
I’ve got a 230SL myself and was worried about the crank issue too. From what I’ve gathered, the Bud’s Benz kits with the updated compressors seem to address the problem pretty well. I drive mine daily in hot weather, and the AC has been a game-changer, but I did have my engine checked before installing it.