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Engine Specific Info and Questions => IDI Engine => Topic started by: Jet A on October 27, 2008, 01:35:55 pm

Title: Oil pressure
Post by: Jet A on October 27, 2008, 01:35:55 pm
What kind of oil pressure is everyone running? my pressure gauge is reading 40-60 psi at idle and nearly 100 psi under heavy foot boost.

Also, I still cant get my damn oil dipstick tube sealed at the block. Oil is leaking like a mofo. I am begining to think something is wrong.
Title: Oil pressure
Post by: autoholic on October 27, 2008, 01:50:30 pm
The spec for a 1.6 TD (when fully warmed up w/15w40) is like 10 psi @idle I think. My Samurai motor was running like 12-14 at idle when fully warmed up, when cool it would peg the gauge.

Is the crankcase breathing unrestricted to atmosphere? you must have some pretty heavy blow by to be spitting out the stick.
Title: Oil pressure
Post by: zukgod1 on October 27, 2008, 01:53:28 pm
Where are you reading it at?

A rule I have always lived by is a min of 10 psi pr 1000 rpm.

So 3000 rpm is a min of 30 psi.

Those #'s are off the head not the oil filter mount. Need to read pressure at the end of the system.
Title: Oil pressure
Post by: autoholic on October 27, 2008, 02:01:56 pm
Good point,
I saw a spec in the VW shop manual which called for reading a Quantum TD differently then others - I don't know why. Spec called for 7psi at idle which seems low (?)
Title: Oil pressure
Post by: stewardc on October 27, 2008, 02:14:54 pm
On my just-broken-in AAZ running Mobil 1 TDT oil, I'm getting 1 bar (14-15 psi) warm idle. Pegs the gauge cold.
Title: Oil pressure
Post by: Jet A on October 27, 2008, 03:24:05 pm
Sorry, the specs given were oil cold. have not gotten to operating temp yet.

Its not comming out the tube, its comming out the base of the tube. where it connect to the block. I dont have an oring on the top of the dipstick, no oil comming out of there.

crankcase breathing unrestricted? Valve cover tube port is open to atmosphere.

running 0w-30 chevron. pressure being pulled just before block after filter and oil cooler(aftermarket) via a sandwhich plate.

I did notice the pressure dropped once it was warmmer. 15 or 20 seems closer. maybe is the viscosity of the oil. Still 100psi when its cooled? seems awfully high.
Title: Oil pressure
Post by: zukgod1 on October 27, 2008, 04:43:37 pm
You need to read it @ the head. Move the sender.
Title: Oil pressure
Post by: Jet A on October 27, 2008, 04:57:25 pm
how do you propose i do that? move the stock sender and re drill and tap the head? or find an adapter? what size are the threads in the head?
Title: Oil pressure
Post by: zukgod1 on October 27, 2008, 08:13:53 pm
Remove stock sender, I just used 1/4" NPT, the fitting that came with the oil pressure gauge. The light will go out with the wire un plugged which is not a problem if your reading the oil pressure at the head.one.

Reading it at the filter is before everything, after the filter it goes to the IM bearings, crank and rod bearings then the head. The head is the last to see the oil.
Title: Oil pressure
Post by: maxfax on October 27, 2008, 08:25:08 pm
I'd be curious to know what your pressure is at the head..... Had two early N/A's that had crazy oil pressure till they broke in...  That was on 5w20 taking the reading at the head..
Title: Oil pressure
Post by: gldgti on October 28, 2008, 01:12:28 am
my AAZ with 180,000km's on it reads:

idle (900 rpm) 13-15psi HOT (at the head)
cruise 3000rpm freeway 42-25psi HOT (at the head)

you can buy 3/8 NPT brass fittings pretty cheap. i used a male-male joiner, a 3-way female t-pice to plumb in the sender AND the dummy light, so that i have both.

running 15W-50 Penrite HPR diesel, semi-synthetic.
Title: Oil pressure
Post by: Jet A on October 28, 2008, 09:22:00 am
Head is not tapped npt. its some sort of straight pipe. oil pressure sender is 1/8 npt.

3/8 npt is freaking huge for an oil sender.
Title: Oil pressure
Post by: Vincent Waldon on October 28, 2008, 09:41:43 am
Unless someone has done some fancy plumbing, both the oil filter flange and head oil pressure senders are tapped M10x1 from the factory.  Same with the extra port on the flange, where equipped, for oil temperature.

Which is why people get the two different oil pressure sensors in the wrong spots all the time.

On cars with a turbo oil filter flange the fitting for the oil feed to the turbo is bigger... I vaguely recall M12x1.5 perhaps.
Title: Oil pressure
Post by: zukgod1 on October 28, 2008, 10:15:41 am
Mine was NPT, maybe by someone in the past but 1/4 was the one.

I used a metric adapter on the oil filter flange for my bypass filter.
Title: Oil pressure
Post by: 53 willys on October 30, 2008, 06:10:48 pm
what plugs the hole on the dipstick tube?? (block side)....I got a rubber oring and a copper washer....mine started to leak today...I think its cause I was experimenting with some crank case venting...
I'm just wondering what is factory to seal the oil dipstick tube??
my old engine never had anything on it when I pulled it apart...
Title: Oil pressure
Post by: zukgod1 on October 31, 2008, 07:29:40 am
O-ring is all.. Loosen the bolt holding the dipstick and push down on the tube and tighten at the same time to put some pressure on the o ring.

I agree though, you probably had some venting issues..
Title: Oil pressure
Post by: Jet A on October 31, 2008, 12:33:02 pm
Quote from: "53 willys"
what plugs the hole on the dipstick tube?? (block side)....I got a rubber oring and a copper washer....mine started to leak today...I think its cause I was experimenting with some crank case venting...
I'm just wondering what is factory to seal the oil dipstick tube??
my old engine never had anything on it when I pulled it apart...


JB weld..... :oops:
Title: Oil pressure
Post by: zukgod1 on October 31, 2008, 12:44:29 pm
Quote from: "Jet A"
Quote from: "53 willys"
what plugs the hole on the dipstick tube?? (block side)....I got a rubber oring and a copper washer....mine started to leak today...I think its cause I was experimenting with some crank case venting...
I'm just wondering what is factory to seal the oil dipstick tube??
my old engine never had anything on it when I pulled it apart...


JB weld..... :oops:




 :lol:  :twisted:  :lol:  :twisted:

JB weld is your friend..
Title: Oil pressure
Post by: rabbitman on October 31, 2008, 01:19:11 pm
I got 50psi@head hot. My bentley only says min 28psi@2000rpm I get about 35psi @hot 2000rpm. Not sure 'bout idle.