Hoover mod question

[Axitech]

New aluminum case. Looking at possibly doing the hoover mods to it as I build the motor. Specifically, I'm at the 'drill the oil passages to connect the cam gallery to the lifter gallery on the right case half'. Anyone done it at home, with a hand-held drill? I've done all the measuring, several times. I think I can do it here, but want to hear the experienced guys say it's possible, or not possible, or it's a horrible idea.

If it's not out of the question to do it, what size drill bit. I swear, I searched high and low and cannot find that answer. It looks like it would have to be less than 5/16", but other than that, I can't tell.

Thanks,
Y'all have a Merry Christmas too!
_________________
He said to them, “But now if you have a purse, take it, and also a bag; and if you don’t have a sword, sell your cloak and buy one. Luke 22:36


The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.-Thomas Jefferson

[theDrew]

are you willing to buy a new case if you screw up?
_________________
Turbo 2276 MS3X build http://www.thesamba.com/vw/forum/viewtopic.php?t=673125
1985 Vanagon Campmobile w/ 2005 EJ25

[slalombuggy]

It's an easy mod I did it on both my aluminum cases with a cordless drill.

I think it's a 1/4" drill. Pull the plug out and you'll be able to fit a short drill bit on the hole to check and make sure.

I used a steel rod to measure to the end of the bore and then measured from the side of the web to the center of the hole in the cam journal and added those to get the depth. Then I marked the bit with a piece of tape.

I drilled the main galley out first and then drilled down through the journal,angling it slightly towards the back of the case as the hole is a bit bigger than 1/4". Clean it out good and tap for a pipe plug and you're good to go.

brad

[58Dub]

its easy to do.... jsut measure and mark your bit for depths
_________________
58 Beetle (now just a pile of parts in the corner)
60 Beetle (2221 turbo under construction)
70 Beetle Baja project

[esde]

http://www.thesamba.com/vw/forum/viewtopic.php?t=599478&highlight=hoover+mod
learn from my mistake

[ALB]

Mr. Hoover claimed 7/32 (or 1/4" if you didn't have the smaller size) was big enough, and Mark Tucker has done it with a 3/16" drill (which when you think of it should provide plenty, as all your looking for is a steady supply), so 5/16" is rather large. With the possibility of going through the case going up with the larger sizes it might be a good idea to stay on the small side.
_________________
On a lifelong mission to prove (much to my wife's dismay) that Immaturity is Forever!!

[Axitech]

picked up a 5/16" bit tonight. It's too big, . I'm going to go with 3/16".
_________________
He said to them, “But now if you have a purse, take it, and also a bag; and if you don’t have a sword, sell your cloak and buy one. Luke 22:36


The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.-Thomas Jefferson

[EPETREA]

Who manufactured the case? I was to the point of drilling the same yet when I measured the area below the lifter boss, it seem to taper off and if I had drilled I most likely would have drilled through the casting. Pay close attention to the horizontal area between the thrust #1 cam bearing boss and #4 exhaust lifter. Measure down on outside of boss to be drilled vertically (crank pulley end)

I have my case sealed up but will try to find some pics to show what I am talking about. My case is from CB. I did however do the other mods and I'm not saying it cant be done, actually I think as long as there is enough meat in the area where you are drilling I think it will be fine.

Another option is to have the area built up by someone who knows how to weld aluminum (if you don't) and then drill. If you do , don't forget to lightly deburr your lifter bores where the bit enters.

[58Dub]

pretty sure I used a 1/4 inch bit
_________________
58 Beetle (now just a pile of parts in the corner)
60 Beetle (2221 turbo under construction)
70 Beetle Baja project

[EPETREA]

Who manufactured the case? I was to the point of drilling the same yet when I measured the area below the lifter boss, it seem to taper off and if I had drilled I most likely would have drilled through the casting. Pay close attention to the horizontal area between the thrust #1 cam bearing boss and #4 exhaust lifter. Measure down on outside of boss to be drilled vertically (crank pulley end)

I have my case sealed up but will try to find some pics to show what I am talking about. My case is from CB. I did however do the other mods and I'm not saying it cant be done, actually I think as long as there is enough meat in the area where you are drilling I think it will be fine.

Another option is to have the area built up by someone who knows how to weld aluminum (if you don't) and then drill. If you do , don't forget to lightly deburr your lifter bores where the bit enters. Here is a chart of the mods. area of concern is the lower red circle between boss and lifter bore for #4e

[slalombuggy]

Both my cases are from CB. Didn't have a problem with going through the case.

Editted my previous post as I found my build sheet with drill sizes on it.

brad

[Axitech]

It's an Autolinea case.
_________________
He said to them, “But now if you have a purse, take it, and also a bag; and if you don’t have a sword, sell your cloak and buy one. Luke 22:36


The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.-Thomas Jefferson

[raul arrese]

I did my autolinea by hand , its actually better by hand so u can go in at an angle , the angle is so you will meet with the other passage and not go out of the case and ruin it , well even if you did go through it could be fixed , aluminum is easy to fix.
_________________
" Hot vw feature , may 2014 issue "
" 2013 Bug Jam class winner "
" Bug Jam best motor and best paint "
" 2013 Lakeland Classic Best of Show "
" 2014 Show and Shine , First in class "
"
Like my facebook https://www.facebook.com/pages/Raul-Arrese-custom-fabrication-and-performance/1832968110262608

[Howard 111]

I would never do any of Bob's mods. They may actually help this or that, but I want to run my engines based on the original design, but get as much HP out of it I can. But that's just how I would do it. You could wring real HP out of them long before Bob came along.
_________________
1973 Karmann Ghia
Turbocharged, Fuel Injected
http://www.thesamba.com/vw/forum/viewtopic.php?t=531270

[mcmscott]

Or you could just start another thread about the same thing!
_________________
There are no stupid questions, only stupid people,

68 Ghia
67 T-1
65 Notch
02 Mexican beetle
74 Thing
15 Long travel rail
07 Nomad
05 f-250

[Howard 111]

I looked through all the Hoover Mods, and I actually have one in my current engine. Connecting the oil groves on the lifters. Berg did that on his lifters a long time ago. Then Bob came along...after Berg was dead...and made it look like HIS mod. Oh well, to each, their own.
_________________
1973 Karmann Ghia
Turbocharged, Fuel Injected
http://www.thesamba.com/vw/forum/viewtopic.php?t=531270

[Axitech]

[Axitech]

Ok, I did it! Lots of measuring, praying, more measuring, then a drilling. really slow. I drilled to a depth where the lifter bore hole would barley intersect the cam bore hole. Then I drilled the cam bore hole , angled like some advised, then really slowly advanced the bit until it broke through. I pushed just a bit further until I got to the depth of what the lifter bore hole would be, and stopped. Went back and drilled the lifter bore hole through until the two were fully intersected.

Later on I went back and drilled the cam bore hole to 5/16" so I get lots of flow to the point where the lifter bore hole is 3/16". Lots more measuring and it looks like I missed blowing through by a pretty wide margin. Just to reassure myself, I flipped the case, open side down, and filled the 'valley' with really lightweight penetrating oil. If I did break through, it should seep out overnight. We'll see, but I am very confident my wife won't be shooting me anytime soon.

Another question. On the third pic, bearing surface closest to the flywheel, I saw a hole in the bearing mounting surface (looking again, it appears to be on the back of the flywheel seal area) that goes into the crankcase. Normal, or needs plugged. Purpose?

_________________
He said to them, “But now if you have a purse, take it, and also a bag; and if you don’t have a sword, sell your cloak and buy one. Luke 22:36


The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.-Thomas Jefferson

[esde]

Nice work!

[mark tucker]

in addtion to that, if you do widen/deepen the slot going around the center cambearing so it flows more, be sure to only widen on the pully end of the slots, due to the stroker clearancing the forward side is alreays way closeer than comfert .Ive seen some that were almost clearanced right into the slot, and thats lost oil pressure inside the engine where you cant see it being sprayed and lost. I dont enlarge the oil gally going through the lifter bores but I do enlarge the gally going from the driver side between the cylinders that go's to the center cam bearing tower. it's kinda tiny.