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I am lost!!!
Hi everyone, I hope someone can help!! I just installed a BBC Mark 4 built 588 motor in my boat, first three times out no issues fourth time about 10-15 minutes of use white smoke started pouring from the valve cover breathers- more on the right than the left. Did a compression check and everything it dead on, changed the oil- no water in oil, checked carb power valves not blown. Motor runs and sounds perfect doesn’t skip a beat. I don’t think it’s water reversion because I don’t have a big cam.....what the heck am I missing?? Thank you. |
What do the plugs look like?
Any dark coloring or are they all bright white? What exhaust ? |
Temp?
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Smoke
Plugs are perfect. I have EMI Thunder dry exhaust. Temp is normal |
Smoking
Sorry to do this guys but I have to have 10 posts to show a picture/ video so I am going to do nonsense posts |
Smoking
I want to run it this weekend for the last fun run i bummed |
Smoking
Really had enough with this boat- bought it had to put a new transom, transom assembly, motor, drive, exhaust |
Smoking
Almost to 10 posts I am very sorry |
Smoking
My wife hates me because of this boat |
Smoking
Ok last nonsense post thanks for bearing with me |
Smoking
Nope sorry need two more |
Smoking
Ok next one thanks again |
Smoking
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have you pulled the valve covers, that's crazy, does it smell ?
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Smoke
Valve covers taken off and didn’t notice any issues. Smells like burnt oil
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Smoke
What would be electrical inside the motor? I am screwed if there is anything that’s supposed to be in there lol |
Originally Posted by Raging Boater
(Post 4706944)
What would be electrical inside the motor? |
Are you sure its coming out of the breathers and not a leaking valve cover gasket getting oil on the exhaust manifolds ? That's crazy looking :( Is it smoking out of the exhaust at all ?
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Smoke
Right I have the sensors but idk how those would cause this... 100% sure it’s coming from valve cover breathers. It gets worse as the engine warms |
might be a little messy, but start it without the covers on
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Is it puffing like with pressure behind it or just gently drifting out?
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Smoke
Starts as drifting as motor warms it starts puffing
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Video
937833eb-a38f-47e3-9c01-354 |
how many hours are on the engine ? are there valve stem seals installed
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Hours
2-3 hrs, yes valve seals, however I was told a lot of performance motors don’t have them |
Video
I can’t get the video to play |
Curious
Originally Posted by F-2 Speedy
(Post 4706952)
might be a little messy, but start it without the covers on
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Good chance you have damaged a piston/s and pinched a ring/s but i would expect a plug or two to show some oil
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Tested
Originally Posted by Mbam
(Post 4706971)
Good chance you have damaged a piston/s and pinched a ring/s but i would expect a plug or two to show some oil
checked plugs- perfect compression test was dead on also the motor runs normal it doesn’t skip or sputter at all |
Does the MK IV run a lifter valley pan ? what intake are you using...Bowtie 10.2 block
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What type of oil are you using?
Not that it is the cause just asking |
Originally Posted by abones
(Post 4706974)
What type of oil are you using?
Not that it is the cause just asking |
wondering if there is some type of additive in the oil that burns off as it warms up,
There should never be any spitting out the breathers if the engine is in good shape, do you run a PCV system? |
I would do a leak-down test, it will show problems not identified by a compression test.
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is it smoke or steam???
maybe you have alot condensation in motor, when gets hot , pushing out breather. but it looks more like smoke?? |
You're absolutely sure the oil looks good? No fuel smell, no white streaks, foamy, changes in viscosity? What ever this is, it has to pass through the crank case. I had an old Pontiac 389 that the valve guides were so bad the engine wouldn't run with the valve covers off and it didn't smoke like this. Puffing indicates this is a combustion related issue or at least related to one or a few cylinders not all. Is this a closed cooled motor or seawater? If you have through hull exhaust watch your exhaust closely, have someone follow you and see what your exhaust is doing. What temp does your motor run at?
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odd it was fine the first few times out, you may have cracked a ring, or somehow created this during the breakin ????
please keep us posted! |
Originally Posted by abones
(Post 4706976)
wondering if there is some type of additive in the oil that burns off as it warms up,
There should never be any spitting out the breathers if the engine is in good shape, do you run a PCV system? |
Originally Posted by abones
(Post 4706984)
odd it was fine the first few times out, you may have cracked a ring, or somehow created this during the breakin ????
please keep us posted! |
Originally Posted by Raging Boater
(Post 4706986)
Wouldnt that show on a compression check? So did you build the engine or somebody else ? |
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