Lifter Valley Oil line Question

[RAMBLINFSJ]

When I drill and tap for the Lifter Valley Oil Line Mod, what size hole would you recommend drilling as a minimum? Also, what minimum size line would you use? I plan on just buying what I need at the hardware store so I just need the minimum recommended size of the fittings and the line. Thanks guys.

[jeepsr4ever]

Well anything 1/4" or bigger helps. Many have used a small 1/4" brake line believe it or not. Most use a -10n with a 1/2npt tap. When you drill for a 1/2-npt you want to get a close 45/64" drill but I suggest a 23/32 and make sure to grind off the first 5 threads of your tap or you wont get it deep enough...yep thats 5 threads on your 1/2-npt tap. Be sure and test fit you adaptor whichever way you go and keep in mind intakes like the R4B have a large baffle that will hit most valley lines and wont let the intake sit down all the way. You can ball peen a large dent in the baffle and it wont effect anything.

[RAMBLINFSJ]

jeepsr4ever, I am beginning to like you, not like that, you're the man. :lo1l: Thanks for the help.

[jeepsr4ever]

Just passing on the grape seeds man :?:

[fifesjeep]

Well anything 1/4" or bigger helps. Many have used a small 1/4" brake line believe it or not. Most use a -10n with a 1/2npt tap. When you drill for a 1/2-npt you want to get a close 45/64" drill but I suggest a 23/32 and make sure to grind off the first 5 threads of your tap or you wont get it deep enough...yep thats 5 threads on your 1/2-npt tap. Be sure and test fit you adaptor whichever way you go and keep in mind intakes like the R4B have a large baffle that will hit most valley lines and wont let the intake sit down all the way. You can ball peen a large dent in the baffle and it wont effect anything.
23/32 sounds kind of big for such a small oiling line plus, what is the passage-way I.D.? You can't go too big.
Here you go man... here is a link that will help you out to decide...
http://ww2.mne.ksu.edu/classes/ME300/Reference/npt%20tapdrill.htm
I personally drilled mine with 7/16" for 1/4" 18 NPT.. Plenty of room on either side for good threads etc.. You want to be careful not to drill off center or completely through it. If so, you might scrap that block unless you want to dump $$$ into repairs etc.

[1980_Cj7]

We made ours from hardware shop fittings and 3/8" soft copper tubing. We got a 45 degree 1/4" NPT to 3/8" flare fitting, and a straight 1/4" NPT to 3/8" flare fitting, 2' of 3/8" copper tubing, and 2 flare nuts.

BUT, since we have our engine apart anyhow, I'm seriously thinking of redoing it using steel fuel/brake line this time. Reason being, you need to make a hard tight bend on the back end, and it's easier to get a nice bend with the steel than it is with the copper. Don't get me wrong, the copper tubing we made worked just fine, that bend is just too URGLY for my liking. And even though nobody will ever see it, I know it's there. (And yes, I used a tubing bender.)

Just something to think about.

We were able to keep ours flat enough that the intake fit without ball-peening the baffle. We did have to cut a small notch out of the tin intake gasket to clear the front fitting though.

[46flattie]

Have any of you guys had concerns with the tubing cracking over time due to vibration, etc. whether it is copper or steel (stainless especially)? I used Aeroquip SS braided line on mine and have run it for 7 yrs or so w/no issues. Any opinions on the Aeroquip line good or bad? I'm building another 401 right now and plant o use it again.

Thanks, Scott

[Patf10]

my engine builder didnt put mine in. i was kinda angerd by that but its not gonna see alot of revs anyways nothing more than 3000 most of the time

[1980_Cj7]

Have any of you guys had concerns with the tubing cracking over time due to vibration, etc. whether it is copper or steel (stainless especially)? I used Aeroquip SS braided line on mine and have run it for 7 yrs or so w/no issues. Any opinions on the Aeroquip line good or bad? I'm building another 401 right now and plant o use it again.

Thanks, Scott

I actually heard that vibrations are more of a problem with the braided line. Heard that it can vibrate and rub against the underside of the intake and wear thru eventually.

I think it would take an awful lot of vibration to make the copper or steel crack. Who knows?

[82Waggy]

Why put it in at all? It does not do anything but go along for the ride. Can't flow any extra oil - it is looped back upon a feed path from the same source. Doh! 111!!!

[fifesjeep]

:-| I don't know about that... If you have decent oil pressure and you run an extra line that's feeding into the back part of the passage-way.. You'll essentially end-up with more Volume/velocity going to the rear bearings etc... If it didn't or doesn't help then why do all of the High HP/Performance AMC'ers do it?... 111!!! (Along with various other oiling mods etc)... :!:

[46flattie]

I actually heard that vibrations are more of a problem with the braided line. Heard that it can vibrate and rub against the underside of the intake and wear thru eventually.

I think it would take an awful lot of vibration to make the copper or steel crack. Who knows?

Thanks for your input. I suppose that is possible if you use too much line. I have seen no chaffing, rubbing, etc. on mine.

As far as copper or steel tubing cracking, as I think more about it, due to its short length in the valley, it probably doesn't have the opportunity to move enough to allow a crack to develop.

[jeepsr4ever]

I have seen copper fracture but I believe now it was from over-tightening and not vibration related. I have not heard that a braided line can wear through a intake yet....whew seems like it would take many many years :mrgreen:

[82Waggy]

:-| I don't know about that... If you have decent oil pressure and you run an extra line that's feeding into the back part of the passage-way.. You'll essentially end-up with more Volume/velocity going to the rear bearings etc... If it didn't or doesn't help then why do all of the High HP/Performance AMC'ers do it?... 111!!! (Along with various other oiling mods etc)... :!:

I'll give you my best reasoning for my "not needed" opinion.

1) The secondary feed paths from the lifter gallery to the crank bearings are smaller and therefore more restrictive than the lifter gallery - so adding a second feed path from the front to the rear of the lifter gallery will not increase flow to the bearings.

2) As stated above, it is the restriction through the bearings for a given flow rate from the pump that determine system pressure. For a given size of restriction the only way to increase flow through it is to increase pressure.

3) If there is any pressure in the system at all, flow rate from the pump must be in excess of the leakage rate through the bearings and valvetrain. To suggest that pressure decreases as you move downstream from the pump is to suggest that the bearings and valvetrain are able to pull oil from the feed paths in excess of the flow rate of the pump, and that cannot be the case if pressure exists. This is not a free stream system like a river with open capillary branches - at least not until the oil has left the bearings and valvetrain and begins to gravity flow back to the pan - it is a closed pressure system up until the oil has passed through the restrictions at the end.

4) If pressure exists it must be equal from one end of the system to the other. If it is not equal at both ends of the lifter gallery there must be a blockage. If there is a blockage in the lifter gallery that is more restrictive than the feed paths to the bearings you have bigger problems that need fixing.

5) Pressure measurements taken at both ends of the lifter gallery during dyno testing show no measurable drop in pressure from one end to the other. The valley bypass line is in effect tied back to the same feed source at both ends and therefore must have equal pressure at both ends. A line with equal pressure at both ends will flow nothing. The lifter gallery bypass line is therefore of no use.

6) Extended high rpm operation has been known to deplete the oil capacity in the pan by pumping all the oil up top before it can drain back down, resulting in the unporting of the pan pickup and subsequent system pressure loss. Higher capacity pans, improved drainback, and smaller ID pushrods to slow the flow of oil to the top are probably the best solution to this problem.

7) In my opinion the only oiling mod a common lower rpm jeep motor may benefit from, aside from a properly functioning pump and clean system, is a larger capacity pan with either baffles or a swinging pickup to help feed the pump during operation in unusual (high angle) attitudes (more unusual than my own).

[1980_Cj7]

I have seen copper fracture but I believe now it was from over-tightening and not vibration related. I have not heard that a braided line can wear through a intake yet....whew seems like it would take many many years :mrgreen:

No, what I read wasn't that the line wears thru the intake, but that the intake wears a hole in the braided line. Again, just read that somewhere, and can't vouch for it's accuracy.