Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties K style lifter block holes

K style lifter block holes

Post Sun Apr 15, 2018 1:18 pm

Posts: 569
Location: Wa, USA
Does anyone have the location information for the K style holes from the lifter blocks into the crankcase?

Post Fri Apr 20, 2018 8:04 am

Posts: 1731
Location: Interlaken, NY USA

Are you referring to the additional holes added to "G" blocks in later production to drain and or add oil to the tappet area? I might have one of those blocks in the stuff upstairs, I could look.
DD

Post Fri Apr 20, 2018 7:10 pm

Posts: 569
Location: Wa, USA
Dr.,
Yes that is the one. Pics I have found show that it was also done on Ks. I am looking to do it to my U. If you can tell me the hole diameter, the angle, and how far down from the top of the lifter block top the hole is, that would be a great help.

Post Fri Apr 20, 2018 7:29 pm
don

Posts: 593
Location: Spokane WA USA
In the bore, about 1/2" down in the groove, is a #31 drill hole at 30 degrees exiting in a oval just below the underside of the flange, that if extended would lead into the flywheel side of the crankcase.
Is this peculiar to any specific model or just a racers mod? Looks Professional!
Or is this to aid in low RPM lubing of the valve train, ie, servicars? The three I have are screwdown type, both intake, and front exhaust.
None of the 12 U camsides I've seen are drilled to match.
Don

[This message has been edited by don (edited 31 January 2000).]

Woody! do You need A loaner to hold in Your hand?
don.

Post Sat Apr 21, 2018 5:34 am

Posts: 1731
Location: Interlaken, NY USA

Thanks Don, beat me to the punch. I never figured out which way the hole was supposed to work, extract excess? oil or allow more oil.
Woody, what problem are you trying to resolve? I've never used those blocks, although at one time I might have considered retrofitting the late style BTSV blocks with the holes.
I run only the screw type blocks and early covers. With the added oil from bigger pumps, I just couldn't keep all the oil that was working up into the lifter/valve stem area inside. Gave up on the spring clip covers and went with the screw together ones. I groove the early style lifter blocks for sporty o rings to seal them in the cases, countersink the 2 mounting screw holes in the cases and "o" ring them too. Then, use those same sporty o rings stretched some, I'll admit, to seal the lower cover to the block, the screw joint between upper and lower, and the telescoping joint between the 2 upper pieces. It's a process, but it makes the covers oil tight. Oh yes, and custom seals from inner tubes between the upper cover and the valve guide. There's probably a better material for that juncture, but the inner tubes get kinda hot, and mold themselves to the job at hand and seal pretty well.
Just thought I'd pass that on if leakage is your issue.
OH yeah, I also rework the breather pipe that exits the cam cover, make my own. Use the biggest diameter tubing that will fit into that cavity in the cover casting, notch the top so that the side facing the exit area from genny gear flange is taller than the far side for max opening area of the tube at top, then brazed up an extension of the breather on the outside of the case so that this extension runs just above the exhaust pipe past the rear of the cam cover, then slip a large diameter flexible tube on it to carry the breather exhaust over towards the chain.
I also cut down the genny slinger gear until it looks like the flat washer that's mounted on a sporty genny. I eliminate the brass tube slip fitting that "seals" against the gear slinger as well. the resulting gap approximates the space found on a sporty between the "washer" and the cam case. Gives a great increase in clearance and resulting greater breather flow capability. No discernible increase in oil mist in breather output, and gets the breather mist off my exhaust pipe! Always hated that design, with the resultant burned on mess on the exhaust pipe below the breather output. Got some pics somewhere I think.
The idea in all that is that my 88" stroker motor overwhelms the stock breather system I think, and needlessly pressurizes the cam chest momentarily with each downstroke.
All this in the quest for a cleaner motor, hate oil covered machinery :D
DD

DD

Post Sat Apr 21, 2018 6:05 pm

Posts: 569
Location: Wa, USA
Don,
Thanks for the offer. Having one to copy exactly would be perfect. Do you still sell the gasket sets you used to have? If you do, I would like to buy one and then the shipping could be combined and you can just add it to the price.

Dr.,
I am not really trying to solve a problem. I was told by someone who runs these things for LSR that the extra holes aid oiling to the tappet/valve area and eliminate the usual cupping wear on the top of the tappet adjusting screw. I thought it was worth a try. I have custom made valve covers that use several o-rings and do not leak. I am interested in your breather modifications. Do you have any pics?

Post Sun Apr 22, 2018 6:35 am

Posts: 1731
Location: Interlaken, NY USA

pipe800.jpg
pipe800.jpg (233.63 KiB) Viewed 2053 times
breather1.jpg
breather1.jpg (200.56 KiB) Viewed 2053 times
profilegear640.jpg
profilegear640.jpg (121.9 KiB) Viewed 2053 times

Hopefully here are some pics of the modified breather
Doesn't show the modified profille on the breather tube where it fits into the breather cavity.
This system doesn't appear to throw any more oil out the pipe than the original.
Oh yes, the genny gear is the ratcheting type for the fan generator I have mounted. However, the regular slinger style should be able to be modified in the same manner. Just chucked it into the lathe and turned the excess off.
DD

Post Fri Apr 27, 2018 5:33 pm
don

Posts: 593
Location: Spokane WA USA
Woody,
I believe that Don resides in Meridian Idaho.
I am In Spokane WA.
I am awaiting contact from You.

Post Fri May 04, 2018 6:50 pm

Posts: 569
Location: Wa, USA
Don,
I sent you my contact info. Did you get it?

Post Sat May 05, 2018 6:20 am
don

Posts: 593
Location: Spokane WA USA
Woody,
No! -All is well with Contact Now!-
Something was wrong with message exchanges on the board.
I have verified my E-mail address in Profile under Account settings on this board.
Users and Administrators are Yes to E-mail. Users are Yes to Private messaging.
I have sent You E-mail and Private message 2 weeks ago.
My last Private message stored in 2007.
This is being sent through E-mail and PM icons under your name.

don


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