65tripleblack

Is there anyone here who has a crank scraper installed and which does not cause the right side of the pan to leak? If so, how is it mounted and sealed.

How much power is it worth at 7500 RPM?

Pop Chevy

10 to 12 hp. It keeps the crankshaft from wrapping up with oil. I remember that Smokey built a pan with a clear window on the side and saw that the oil would wrap around the crank like rope. I've used one ever since on my race cars. Also keeps the oil in the bottom of the pan where the pickup(s) can get it.

63 340HP

The scraper on my 357 is thin sheet metal and is sealed with Gasgacinch on the pan gasket side and thin silicone on the block side. I use thin silicone on the pan gasket and scraper on the block side. The pan gasket is stuck to the pan with Gasgacinch. No leaks, and a number of 7500+ rpm runs over two years.

You should not have a leak unless the crankcase pressure is excessive and the pan rail is warped.

Power?

DansYellow66

No, I gave up after a couple efforts on my BB. I think a scraper that has a full pan rail surround is about the only way to accomplish a no leak installation - sort of like the Mopar 383/440 oil pan baffle that installs between two gaskets.

Powershift

10-12 HP increase was about the same as the MOPAR engineers claimed back in mid-1960's.

Larry

EDIT: Since those MOPAR engines did NOT wind to 7500 RPM very much, you might see more savings from your engine at those higher RPM.

65tripleblack

Would be good to have power loss as a percentage.

Shift: 439 HP @7500 (wide ratio 5 speed)
Peak: 476 HP @6569
Drop: 429 HP @5250

65tripleblack

I'm thinking about how effective the scraper would be in conjunction with the not very effective flat windage tray that I have installed. It is the original SHP tray.

I saw Grumpy's website, and he uses a much better windage screen which is cylindrical rather than flat. It has built in wipers. I haven't been able to find one for sale. There are full length ones but they won't fit a stock oil pan.

Pop Chevy

Screen is much better than a flat tray, it tends to break the oil mist back down into droplets. Moroso used to sell it, you had to trim it to fit.

PAmotorman

the scraper works better if you have a pan with a kicked out pouch so the scraped off oil has a place to go.

tuxnharley

For those of us not familiar with crank scrapers - and who will probably never need one - anybody got a of the scraper itself?

Thanks!

tuxnharley

https://www.crank-scrapers.com/What%...k-scraper.html

Seems like the term covers many different types of devices - baffles, windage trays, etc. Those I am familiar with.

The pics shown in the link cover all, including some that come mighty close to actually scraping in the literal sense!

63 340HP

Your post brought me back to a frustrating memory, and correction.

My 357 has a low profile 7qt pan and a custom made expanded metal windage screen (diamond screen). When I was test fitting the pan on the engine stand I found my usual method of setting the pan over the pump and sliding in the crank scraper between the block and pan gasket was complicated with the scraper hitting the windage screen. Bending up & out the screen edge sheet metal rail made room for the scraper, but then the screen edge pushed down on the scraper as the pan's baffles were worked over the pump. I spent a weekend trying different ways to get the scraper between the crank and screen with the pan, trying pan studs, bending the screen, and even cutting the scraper (defeating the purpose), and finally gave up. I looked at the screen edge sheet metal and how close it could be bent to fit to the block crankcase wall, to minimize oil climbing the wall from the pan, and called it good enough. The scraper was hanging on a nail in my garage for years as a reminder.

Looking at modern systems the Milodon diamond windage screen is narrower than mine, and sits above the pan rails. You can probably use Gasgacinch and studs to hold the scraper and set the pan without the drama I suffered.

I almost forgot. Check the dip stick entry and path before setting the pan for the final assembly. Mine hit the windage screen, and I had to pull it apart to cut a path through the screen for the stick. It was one of those weekends.

TCracingCA

65tripleblack

I installed mine by screwing it to the right side pan rail for positive location because I fit it by cutting to provide about .005" clearance to the crank. I used 2 flat head screws which I countersunk into the scraper, silicone between the scraper and rail. The gasket is one piece, blue rubber which goes on dry, except for 4 corners.

I might have made a "mistake" by screwing the flat head screws tight while the silicone was still soft. Maybe I squeezed all of it out around the 2 screws. Again, I did this for "positive" location. Should I have let the silicone set up before tightening the 2 screws.

I'm thinking of eliminating the screws and substituting pins. Then I can press the scraper in place without squeezing all the silicone/Gaskacinch/Right Stuff/whatever out.

Thoughts?

65tripleblack

From what I understand, modern close-fitting windage screens fit close enough to scrape the oil off the crank, and should be carefully fitted. They take the place of old fashioned crank scrapers. I also understand that louvers are better than mesh because mesh can let some of the oil get sucked back into the crank from the sump, while louvers are more "one-way" and more effective.

The first photo is Canton's version. The photo shows the version used with a full length sump. Front is to the right. The type used for a SHP oil pan would be slightly shorter in front and is about 70% as effective as the full length version.
The second photo shows the Milodon product for an SHP rear sump pan. Front is to the left. It looks like mesh but is actually a grid of small, directional louvers which supposedly keep the oil in the sump rather than being re-introduced into the wind stream around the crank.

63 340HP

Deleting the silicone may help. A better seal may be found using a thinner gasket sealer like Gasgacinch that is used for sealing metal to metal without a gasket. Letting the scraper float, on pins or with the screw heads set below the gasket surface but a little loose floating on the thin sealer. This should allow the scraper to block to be sealed evenly with the pan hardware to provide more even torque on the pan and scraper gasket sealers.

Motorcycle engine split cases are sealed metal to metal with Gasgacinch, and is preferred to silicone, because it is self leveling, and does not creep with time, and leaves little or no excess sealer in the assembly to get loose and sucked into an oil gallery. My father would kick my *** for using silicone where Indian Head was needed to keep stuff together forever, or Gasgacinch between metal to metal, and Aviation Permatex #3 if it had to remain soft and pliable (I spent a lot of cold pre-race nights and post-DNF days cleaning gasket surfaces to learn the lesson).

During my youthful Pontiac GTO days I made a few crank scrapers for my 400 poncho engines and a buddy's 427 BBC using 5052-H34 aluminum sheet. The stock Pontiac connecting rods are not known for reliability at high rpm, so any help to reduce rod forces was implemented (short of aftermarket rods that were rare and expensive). I don't know about power gains, but with a scraper about 1/4" off the crank and the stock windage tray & pan, the engine almost survived an entire season of racing and street fun with many runs through the timing lights in excess of 6500 rpm. I broke a valve spring, and then dropped a valve and broke a rod, at the Bracket Finals at Famoso (after driving there with 4.88 gears, over 120 miles, to get a flatbed ride home - youthful confidence & optimism). The thing I did notice with the scraper was less oil blow-by through the passenger valve cover vent to the air cleaner, compared to earlier engine builds that previously averaged two or three per year.

TCracingCA

63 340HP

The mesh screen I have looks very much like the Milidon mesh, with somewhat directional diamond shaped expanded metal holes.

TCracingCA

Pop Chevy

For optimum performance the scraper should be within .050 of the rotating assy. Very careful fitting is required. I like to use Yamabond for a metal to metal sealer. Great stuff.