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Old 05-26-2015 | 09:03 AM
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Tim,

I am no engine builder. But I can't help but wonder about temp differential on a fresh engine. You mentioned you do not run stats in another thread, and show coolant temps of 100 or less this time of year. With the engine being new, and the relatively high EGT's that marine engine runs is it possible that is stuck because the valve grew but the head did not because coolant temp was so low?

Bob is a great guy, I'm sure he will do whatever possible within his means to get you back up and running.
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Old 05-26-2015 | 09:05 AM
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I never ran stats and never issues before, so not sure what yet just trying to find cause at this point and how to avoid it again and other engine, very stressed out....
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Old 05-26-2015 | 09:15 AM
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Originally Posted by Full Force
I never ran stats and never issues before, so not sure what yet just trying to find cause at this point and how to avoid it again and other engine, very stressed out....
Well you never had brand new engines before either And lets face it, the water is unusually cool right now, even for this time of year. Breaking in a new engine with coolant temps under 100 degrees scares me, but I am no expert, just trying to give you some perspective.

I run 120 degree stats in mine, and right now am having trouble getting the oil temps I want, because the water is so cold.
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Old 05-26-2015 | 09:28 AM
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Originally Posted by 4bus
Well you never had brand new engines before either And lets face it, the water is unusually cool right now, even for this time of year. Breaking in a new engine with coolant temps under 100 degrees scares me, but I am no expert, just trying to give you some perspective.

I run 120 degree stats in mine, and right now am having trouble getting the oil temps I want, because the water is so cold.
do you have oil t stats?we must keep in mind that when things like stem to guide or lifter to bore clearance is checked the parts should be in a room that is around 70 deg f.
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Old 05-26-2015 | 09:37 AM
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Originally Posted by mike tkach
do you have oil t stats?we must keep in mind that when things like stem to guide or lifter to bore clearance is checked the parts should be in a room that is around 70 deg f.
My oil system is stock merc, I'm sure there are stats but it still effects the temp.


Sure the clearance is set at room temp. My question is what if that head is still at room temp while operating and the valve is at 900 degrees? I think we all have put a bearing a freezer to get it to drop in a race. If the race was room temp and the bearing is hot its not going in.

Why do we warm engines up before using? I have seized a piston in a snowmobile because the piston warmed before the sleeve, no room.

I am not trying to beat Tim down, I consider him a friend. Just saying all new parts and ice cold coolant in a full load 5000 rpm environment maybe could be part of it? Don't they make stats for crossovers?
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Old 05-26-2015 | 09:39 AM
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Originally Posted by 4bus
Well you never had brand new engines before either And lets face it, the water is unusually cool right now, even for this time of year. Breaking in a new engine with coolant temps under 100 degrees scares me, but I am no expert, just trying to give you some perspective.

I run 120 degree stats in mine, and right now am having trouble getting the oil temps I want, because the water is so cold.
Totally get that, I never had issues with other new engines, and scott runs same setup with no issues in cold water, not to say that don't play a role but going off past not having issues, I think my lifter stuck or guide issue plain and simple just got to determine what one
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Old 05-26-2015 | 09:51 AM
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Originally Posted by 4bus
My oil system is stock merc, I'm sure there are stats but it still effects the temp.


Sure the clearance is set at room temp. My question is what if that head is still at room temp while operating and the valve is at 900 degrees? I think we all have put a bearing a freezer to get it to drop in a race. If the race was room temp and the bearing is hot its not going in.

Why do we warm engines up before using? I have seized a piston in a snowmobile because the piston warmed before the sleeve, no room.

I am not trying to beat Tim down, I consider him a friend. Just saying all new parts and ice cold coolant in a full load 5000 rpm environment maybe could be part of it? Don't they make stats for crossovers?
your sc 575 has oil t stat from the factory.we warm up our engines because cold oil does not flow well.the snowmobile engine is a totally different anamil and cannot be compared to a marine engine that runs in much warmer conditions.
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Old 05-26-2015 | 10:05 AM
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Originally Posted by mike tkach
your sc 575 has oil t stat from the factory.we warm up our engines because cold oil does not flow well.the snowmobile engine is a totally different anamil and cannot be compared to a marine engine that runs in much warmer conditions.
Ok, I get the sled thing is not relevant, it was more talking about metals that a direct comparison.

Yes I have oil stats. But they must have quite a bit of bypass because my new coolant temps definitely effect my oil temps significantly. Again, I am not hear to harp on Tim, I just want to learn more and discuss.

I was always under the impression that marine engines had larger tolerances because of the extreme load and the heat it makes, coupled with the cooler engine water temps. The temp delta from ECT to internal engine parts on a marine engine are much higher that a car that is running around at 180-210 all day no?

Tim, with your coolant reading less that 100, what was your oil temp?

I'm still thinking it was a machining issue, as Tim suspected. However, I am curious about ice cold engine temps, and a new engine in high load for break in. I wouldn't think it could be good but I don't know
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Old 05-26-2015 | 10:13 AM
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Up here with a crossover, and this time of year, good luck getting good oil temp before you drop the hammer. And yes, even with a tstat'd oil cooler.

Fact.
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Old 05-26-2015 | 10:18 AM
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Originally Posted by SB
Up here with a crossover, and this time of year, good luck getting good oil temp before you drop the hammer. And yes, even with a tstat'd oil cooler.

Fact.
Why not run a T stat with a bypass to feed the exhaust. I run crossovers and this is how I set up my engines when I went back to NA.
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