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Discussion Starter · #1 ·
Ok where to start. 1999 HP 500's new crane double springs installed in 2005. Motors were test fired and installed in a Sonic we have for sale. Never ran until last week. The started and ran well on fresh Fuel. 3 short runs to check boat out and shakedown before poker this weekend. launched Friday night port motor sounds horrible. Put back on trailer to go home to check it out. had some noise in valve train so pulled outside rocker cover to trouble shoot found 3 visible outer springs broken. Well I had another set of springs so decided to change them and make the run. All in all found 8 outer and 7 inner that were good all the others were broken. Also found inboard head gasket burnt between 3 & 5 when I pressurized the cylinder with air to hold valves. This was at 5:00 am and decided i was done.


So has anyone else had problem w/ these Crane springs They are the same that Merc uses. So now I'm going to tear down both motors. Even Stb motor is strong.
 

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I believe Merc switched to Comp's after seeing same issues.

I have not heard of them breaking so fast though. Interesting.

Do a search in SW and OSO on HP500 valvesprings and you'll find a ton of info.
 

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Discussion Starter · #3 ·
I know the problems w/ 500's and springs these were done while motor was out as preventive maintenance. I did them every 2 years no matter what. But they maybe had 2 hours on them. Any experience with the comp bee hives? I heard they are great in cars haven't heard anything about boats.
 

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I have not heard reports about the beehives made/marketed for the BBC's but the one's that are made/marketed for the small blocks are breaking too. :dead: They wheren't at first because PAC was making them for them, but as freakin usual, they took it over seas and then 'bustage' became more normal.

Also, problem some have with beehives is that since they are single springs is the fear if it breaks. Why ? No other spring to hopefully keep the valve up when the other spring breaks.

If you go beehives get them from PAC.
Website is www.racingsprings.com

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If you do a search you'll see many recomendations with part#'s for Comp, ISKY, and etc.

Personally, I'd probably go with a good dual spring set up from a reputable company like ISKY or PAC. I'd also run a little more psi than the norm.
 

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Interesting thread - i have Crane springs on order (4 weeks so far) #99896 to match the 139021 cams for the BBC's in my Checkmate. I've ordered +.100 valves and expect to shim the springs to hit the correct (installed) height.

I presume the issue with installed height is binding at full open?
 

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Combination of poor spring quality and something a-miss in the geometry. Interestingly enough, not getting a spring close enough to coil bind can be hard on springs as well. Installed height less coil bind less net lift should yield no more than .060" or so. More than that and the spring can be unstable and get into destructive harmonics. Allowing the spring to run closer to coilbind helps stabilize the spring and settle down destructive harmonics. Even more important on "cheap" valve springs. Isky tool room springs are my choice.
Just a thought.
 

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steelcomp said:
Installed height less coil bind less net lift should yield no more than .060" or so. Allowing the spring to run closer to coilbind helps stabilize the spring and settle down destructive harmonics. Isky tool room springs are my choice.
Great information! I finally gave up waiting for the Crane springs - two months - and went with Comp. Better pSI and delivery was two days..
 
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