3b pressurized oil access for turbo?? (1 Viewer)
- Thread starter In2cruisers
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stevebradford
In the shop
- Thread starter
- #4
Sorry brother not getting much from that pic ??
- Thread starter
- #5
Don't know where you are..... might I ask where t
You sourced the T .....metric items like this are hard to find in my area
That's the best part. All the block oil fittings are 1/8 npt. I used a 1/8 male male adaptor to thread the block, brass 1/8 T with one port facing up and one perpendicularly out. Thread pressure sender to the horizontal T port facing out and 1/8 male npt with AN -4 fitting to my oil line facing up (I use AN fittings on my oil lines). if you want more adjustability you can use a 1/8 npt 90degree elbow onto the T for the oil line and instead of putting the T facing up you face it forward towards the radiator and use the 90 to face up. This lets you rotate the 90 degree fitting up towards the turbo or decrease the angle a bit and take some of the stress out of the oil line as they often aren't the ideal length and tend to lay against other objects. I never allow an oil line to touch anything. It will eventually wear a hole and rupture. I lost an engine that way. If that is too wordy I'll see about taking pics as it's easier to understand it when you see it.
cruisedeisel
Toyota's for life
Theres plenty of un-used oil plugs on the 3b oil galley. They run front to back on exhaust side inline with the oil pressure and low oil pressure shut off.
P.S. I was under the impression that the block has British standard threads that are 1 thread per inch off from NPT 1/8th threads. I had the put a greased up 1/8th pipe tap to re-thread before installing all three turbo installations I have completed. The grease was for any metal fillings.
P.S. I was under the impression that the block has British standard threads that are 1 thread per inch off from NPT 1/8th threads. I had the put a greased up 1/8th pipe tap to re-thread before installing all three turbo installations I have completed. The grease was for any metal fillings.
All good solutions. Any of these will offer you an oil supply.
In2, in the picture on post #3 on the right side, middle of picture there is a (10mm I think) plug sticking out. It is inline with the boss that is on the far left by the bolt hole for the bellhousing. That plug is the last one along a ridge in the block which has (iirc) 3 (might be 4) small plugs threaded in. When I was looking for a fitting to supply oil to an AXT turbo many moons ago I discovered the threads on the block are BSP (but so close that NPT are used at times): 3B Oil Pressure???
I don't know if there is enough difference in pressure to change things up, but a fellow I knew way back-when suggested supplying a turbo from the most frontward hole and supplying an oil pressure gauge from the most reward hole. I've never hooked pressure gauges to both to see.
hth's
gb
In2, in the picture on post #3 on the right side, middle of picture there is a (10mm I think) plug sticking out. It is inline with the boss that is on the far left by the bolt hole for the bellhousing. That plug is the last one along a ridge in the block which has (iirc) 3 (might be 4) small plugs threaded in. When I was looking for a fitting to supply oil to an AXT turbo many moons ago I discovered the threads on the block are BSP (but so close that NPT are used at times): 3B Oil Pressure???
I don't know if there is enough difference in pressure to change things up, but a fellow I knew way back-when suggested supplying a turbo from the most frontward hole and supplying an oil pressure gauge from the most reward hole. I've never hooked pressure gauges to both to see.
hth's
gb
You know it fits so well I just though it was NPT. I've never had leaks or even damaged threads on soft brass stuff. Better to use brass then as if anything gets damaged it would bet the fitting and not the block. Only used npt with teflon tape on my 3Bs for 20yrs mind you. Always learn something new!
The block oil fittings on Toyota engines (as well as most Japanese engines) are NOT your standard NPT threads--they are also NOT metric threads. They are BSP (British Standard Pipe). The sender unit is a 1/8in X 28BSP. It is 1/8" in diameter with 28 threads per inch.
The 1/8in NPT fittings have 27 threads per inch. The threads on BSP versus NPT are cut with threads with a 5deg difference in angles. The depths of the threads are also different due to the shapes of the peaks and valleys. The correct male BSP fitting is also tapered. The only thing that happens to fit with an NPT fitting is the 1/8in diameter--otherwise, you might as well just drive a square peg into a round hole.
The correct 1/8in x 28BSP to 1/8in NPT adapters are available from Amsoil, Autometer, and Mcmaster-Carr. From there you can add whatever T or elbow fittings you need.
The other question you should ask if you are adding a turbo is "what are you using for an oil return?" The return is just as important as the supply. FWIW, having talked with two manufacturers, the return should only flow unimpeded, by gravity, straight down to the oil pan. It should never be plumbed in to any other return line, or run back into the valve cover or top of the engine.
The 1/8in NPT fittings have 27 threads per inch. The threads on BSP versus NPT are cut with threads with a 5deg difference in angles. The depths of the threads are also different due to the shapes of the peaks and valleys. The correct male BSP fitting is also tapered. The only thing that happens to fit with an NPT fitting is the 1/8in diameter--otherwise, you might as well just drive a square peg into a round hole.
The correct 1/8in x 28BSP to 1/8in NPT adapters are available from Amsoil, Autometer, and Mcmaster-Carr. From there you can add whatever T or elbow fittings you need.
The other question you should ask if you are adding a turbo is "what are you using for an oil return?" The return is just as important as the supply. FWIW, having talked with two manufacturers, the return should only flow unimpeded, by gravity, straight down to the oil pan. It should never be plumbed in to any other return line, or run back into the valve cover or top of the engine.
My square pegs go into their round holes easily by hand and don't mar any threads and don't leak so I'm ok with them. I've only built a couple dozen 3B turbos over the years but what do I know.
Thanks
g
Thanks
g
- Thread starter
- #12
Thanks Boys...
cruisedeisel
Toyota's for life
I have attempted threading in the 1/8th npt with no luck several times. I can't believe you did it gerg.
Yeah, so much so I wonder if there is a variation in the blocks or something? I have a spare block in the shop I'll test on tonight just to be sure. I mean it was easy enough it was simply a non issue for me.
whitey45
SILVER Star
No problem here as well!
- Thread starter
- #16
Same here...no joy......ordered a BSPT fitting via fleebay
Well I'm sorry I steered you wrong. I don't know what's up with my block but always better to use to right fitting. Could you post up a link for your fitting? I'll have to buy one to check it out.
Thanks
g
Thanks
g
RufusTheDufus
SILVER Star
I kinda agree. I forced a 1/8" NPT into my H block for a mechanical oil pressure sender. Seemed to fit well at first but when I tightened it the brass threads on the fitting that came with the kit stripped right off of it. The BSP-NPT adapters are fairly cheap on Ebay. I just bought 5 of them this week for I think $US3 ea.
Edited to add:
I bought these
- Thread starter
- #19
No worries.....I recieved a BSPT adaptor I ordered in the mail today....nice fit, screwed right in
My block had two sending units one below #1 and the other below #2 as is the one in picture 1 above.....so I did as same pic did but went with both sending units at the T and dedicated the #1 port to the turbo feed
Very well written Redrock,
You are correct. The BSPT is an oddball in various ways. The oil return for the turbo kit he is describing is built by us and includes a 1/8BSPT. The return line is as you've described, unempeded, 1/2" with no 90's that loops from the turbo drain directly into the oil pan via a weldable bung.
