Reversion with mild cam???
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Just had a brand new Tyler Crocket 502 hydraulic on me due to reversion. Tyler tore it down and there was water in all 8 cylinders. He thought for sure it was due to a backwash situation, but I was in the marina 100yds from my slip and it was dead calm. I was having some carb issues that day and it was hicuping when this happened, but I'm still shocked that it would ingest this much water.
The cam is pretty mild (114 lsa), but I can't keep an O2 sensor alive, so I know I've been getting at least a little reversion all year. At one point I took the sensor out and felt water even at 1000 rpm.
We're running a stainless marine exhaust that is dry all the way to the tail pipes. We're talking about making it a completely dry exhaust or at least welding up most of the water holes and running dumps.
Any suggestiong? Can I run any sort of flapper valve in the dry section of the exhaust, or will the heat destroy them? Or will flapper valves even do anything with actual reversion, or do they just protect against backwash? I'd really rather not run completely dry.
The cam is pretty mild (114 lsa), but I can't keep an O2 sensor alive, so I know I've been getting at least a little reversion all year. At one point I took the sensor out and felt water even at 1000 rpm.
We're running a stainless marine exhaust that is dry all the way to the tail pipes. We're talking about making it a completely dry exhaust or at least welding up most of the water holes and running dumps.
Any suggestiong? Can I run any sort of flapper valve in the dry section of the exhaust, or will the heat destroy them? Or will flapper valves even do anything with actual reversion, or do they just protect against backwash? I'd really rather not run completely dry.
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I'm running stainless Marine manifolds and risers on a blown 498 C.I. with a 112 lobe center 714" lift solid roller camshaft with extremely high duration and have NO reversion problems... Food for thought. Might want to look somewhere else to the problem for peace of mind......
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you problem might be because you are using too high of a lobe seperation on the cam,i was told that you if you use a 112 degree or less of seperation you will never have reversion problems,just a thought
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In this setup, the tailpipes are the tips and go right through the transome. Water is released right at the exit to the atmosphere. Pipes are very close to the water which is why Tyler asked about backwash, but we're sure there was no wave in the marina.
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I'm running stainless Marine manifolds and risers on a blown 498 C.I. with a 112 lobe center 714" lift solid roller camshaft with extremely high duration and have NO reversion problems... Food for thought. Might want to look somewhere else to the problem for peace of mind......
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Are you sure it is not an intake problem? New motor, right? First time out?
P.S. How is the new drive?
DAve
P.S. How is the new drive?
DAve
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Yes, wet Stainless Marine which is why I commented here. Something just does not sound right. What are the cam specs? At a 114 deg lobe center it would be hard to achieve reversion on any reasonable cam. Maybe the cam specs are incorrect???? I know I'm reaching here and I'm positive Tyler checks all the cams when indexing but It's a thought.
Last edited by ghittner; 09-17-2007 at 09:44 AM.