Thread:

Blow by problem 496 BBC alcohol injected

We run puke tank & the valve covers are vented. When it's cool(motor not air) it will spew oil all over the back of the boat & still draining like 10oz mostly oil outta puke tank. Will adding a vacuum pump help or do we put non vented valve covers on & keep draining the puke tank?

Okay anybody got a solution, advice or maybe just a shut the hell up and get to moppin oil??

Originally Posted by wagspe208

Your vents should be to the front side of the valve covers. (front of boat)What engine?Why are you running your engine cold?What do your vents look like? Oil separator style, or just adapters for the tubes?Whos puke tank?Wags

Thanks for the advice Steve & got the link u sent too. oh lemme know if you can't find somebody to pick up ur wheels in Witchita falls, I can bring em to wheatland.

After mulling this over last night I realized that the day I drained so much out of the puke tank it was morning, Sunday morning. So it would make more sense that the excessive amount came from Sat's last pass when the oil was hot and thinner. We always warm it till the pan & head is hot to the touch. Once I did have the barrel turned around and it was so fat you could see the fuel coming out the zoomies, but figured that out quick like since we were on warm up and in a hurry.

Do you have any kind of baffle in the valve cover below vent/burndown? It's possible the burndown is lined up with a rocker arm and oil is getting flung out the vent. I found on my drag boat with the burndowns in the wrong place it would put the same amount of oil in the puke tank at the launch (Rear of valve cover). Same problem on the Kboat under deceleration (engine turned around same valve cover). Fixed it with an 1/8" peice of aluminum 3"X8" inside the valve cover using the burndown bolts. I spaced it down with 4 washers. No more problems. My $.02

Originally Posted by FLTFLYN

Do you have any kind of baffle in the valve cover below vent/burndown? It's possible the burndown is lined up with a rocker arm and oil is getting flung out the vent. I found on my drag boat with the burndowns in the wrong place it would put the same amount of oil in the puke tank at the launch (Rear of valve cover). Same problem on the Kboat under deceleration (engine turned around same valve cover). Fixed it with an 1/8" peice of aluminum 3"X8" inside the valve cover using the burndown bolts. I spaced it down with 4 washers. No more problems. My $.02

No baffles below vents, hell not even a screen. We also thought about swapping the valve covers from side to side & flipping them (so the bolts line up) so the vents would be further forward and install longer hoses and have them come off the front of the covers instead of the rear where they are now. Was told running vented puke take AND a vacuum pump was as redundant as wearing two bras. I think we may try plugging the vents on the valve covers and just run it a couple times with nothing but puke tank then install the vacuum pump and see what changes if anything. So 1/8" thick 3X8 inch ~ like a patch held in place by the bolts? Then vent doesn't have internal/external bolts to hold it in, its more like a single allen screw collar like a itty bitty prop shaft collar with only one screw in dealy whopper.

An engine built for blown alky requires much less skirt clearance in the cylinder bores, one setup like a gas motor will have far too much piston slap and will effect the ring seal.
Keith