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Sorry I'm not familiar with that brand. But maybe you can help me, or anyone else. I switched oil from merc 25w 40 to Penzoil 40w high performance marine oil. Since I have, my friends and I have noticed smoke at start up and my plugs fouling up with less idel time! We wonder if the oil has caused this. I'm going to do a compression test tomorrow to make sure the is no loss. Has anyone herd of this happening? My engine is a HP500EFI with 120 hours.
 

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Marvel mystery oil is and additive oil. You can also use it to mix with gas in motorcycles. I have recently tried it and other than some smoking (probably burning up sludge and cleaning the sytem out) seems ok to me. It actually stopped oil from accumalitng in my bilge. I do not have any leaks in my system and I do change my oil and filter every 25hrs. My friend who is a harley mechanic siad it is great for all the gaskets and seals.

I have heard on this board and others great stuff about Amsoil and Redline. A little pricey but definetly less than the cost of the engine.
 

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JG-It was good for Harleys, especially when they took the lead out of gas. A capfull in a tank helped lube the valves. I don't think I would use it in a current motor, especially one with FI.

Based on police fleet experience-engines run almost 24/7-idle a lot and also power up a lot-the best thing to do is frequent oil changes. Remembering that oil also serves as a garbage can-a filter can only do so much-so take out the trash on a regular basis. Pull a valve cover on an old engine that has not be serviced regularly and you will find the trash buildup in the valles and rails. We looked in 80-100k engines that had 3,000 oil changes and they were perfectly clean.

Unless you have an extreme heat operation-the cost of sythetic oil in an engine would be better spent with a good straight oil and more frequent changes.
 

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CJ-Don't know why you have problems but it shouldn't be the oil. With the straight 40 you need to spend a little more time to warm it up at idle before you take off-but the oil should't be causing the smoke or plug fouling.
 

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Canada Jeff, in very rare cases, I've seen where different oil brands will not interact together because of their additives. This will usually affect a tired engine by way of cylinder washdown, much like a flooded engine. Its hard to prove, but it can happen.
Sometimes adding a fuel additive to an injected engine can produce the same problem of washing down the cylinders and resulting in compression loss. Check for high oil level or fuel smell in the oil. :(
 

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I've used Marvel to "Fog" motors down for years. Just poor a little down your carb before you shut off your engine after it's flushed. This will prevent the moisture from corroding your internal parts.

Doug
 
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