Jump to content

RB26DETT into 240Z Beginner Progress


Am I a complete idiot?  

32 members have voted

  1. 1. Am I a complete idiot?

    • Yes, either that or completely insane.
    • No, props to you!

Recommended Posts

  • Replies 404
  • Created
  • Last Reply

Top Posters In This Topic

straight up, sorry for downing all your hard work. ive been having a ♥♥♥♥ week and just got told im getting fired..................wtf.

anyways, good work so far, im gunna be doing this as well, i guess im just a huge proponant of suspension mods first, then body, then the engine, but then again, ive never swapped in another engine in any of my personal vehicles, and the customers had alot of money.

anywho, good work, i just know what want to do with the engine before i slap it in.



p.s. who ever said overkill is overkill.......perhaps its just the right about of kill

Link to comment
Share on other sites

That's exactly how I've always felt. Seems like getting the car ready and actually driving it sooner even if that means it might break down sooner and (heaven forbid) you have to do some work on it, you still have a net gain over having the car permanently under construction to be a really sweet car when you're 80.

Link to comment
Share on other sites

  • 2 weeks later...

Quick update. Most of the wiring on the engine side is done, just a few loose ends. Everything lights up and a few gauges are "working". First turn of the key and it hopped over easily. So far so good.


Soon I'll add pictures of all the points of interest for the wiring, but it's going to be tough to remember what all I did for the write-up now that a lot of it is taped up.

Link to comment
Share on other sites

Well stated my good sir. Today I finished all the essential wiring to fire it, but the water temp sensor won't be in til tuesday or so, and I need to pick up another ignition relay. Apparently all stores in socal are allowed one relay at a time and can only order one per month. I ended up getting an ignition relay for a maxima to plug right into the harness without removing the original plug, but it requires two of those as well.


Then it's just add coolant again, cross my fingers and turn the key. My prediction is that it will start with plenty of tlc, but with all the fudge factors I put into it over the past year, it will probably run pretty rough until I figure out all the "what ifs." Just in case, I'll have the camera ready.

Link to comment
Share on other sites

Just dropped by to catch up on your swap - I have been mad busy with work and have absolutely no time for my car at the moment - its distressing!!!


Glad to see that you are still 100% focused though and making good progress.


You sound like you are nearly there so good luck and watch out for the dreaded detonation!


Oh yes - and I havn't got my temp sender sorted either. I am monitoring the temp using the Apexi Power FC hand controller but it would be nice to have my stock gauge working.



Link to comment
Share on other sites

You know that idea hadn't crossed my mind until now!


I keed, I keed. The z sender isn't threaded at all. Also it is larger by all means.


I tried out both senders today, and they have different rates of change (readings are closest at low temp and the rb sensor has a wider spectrum). I'm considering adding a resistor to the rb sensor just to get it to match the z sensor at regulated temp and labeling the ends of the gauge "cold" and "hot" respectively. At least until in the future I decide to upgrade the guauges or rewire it.

Link to comment
Share on other sites

I just realized today that Chris Rummel already discussed using the stock temp gauge for the rb swap. He confirms that the rb sensor will not work for the s30 gauge. Unfortunately he couldn't find the ohm specs on the l6 temp sensor, so he just used it and made an adapter hose to get it to work.


My hope is to figure out the specs of my l6 sensor and find an alternate sensor with the same specs but also the same size as the rb sensor so I can screw it into the stock port. If all else fails I can go his route, which isn't really bad at all.


Just got my RB25 in and running a couple of weeks ago. Ran into the same thing with the temp sensor, but wanted a more elegant solution than adding an aftermarket temp gauge or inline sensor. I usually have multiple projects going on at once, and for the first time it worked to to be a benefit. Knowing that Nissan crosses over many parts, I scoured the garage for a similar sensor. By pure luck, it didn't take long - I had a '91 240SX KA24DE on an eng stand, and sure enough the sensor matched size and style. Taking a multi-meter to it, it had the same resistance at ambient temp and the orig Z sensor. Lacking time, I went ahead and tried it out. Just as I hoped, it read just left of center on the stock Z gauge with the eng at operating temp. It even ran midway right of center one time when I forgot to hook up the electric radiator fan. The toyota one from Chris R's install article (LOTS of good info there) was too small in diameter and wrong thread pitch.

Hope this helps.


In the pic below starting from the left:

Stock '77 280Z, '91 KA24DE, stock RB25DET, Toyota one

Temp sensors_thumb.jpg

Link to comment
Share on other sites

In the pic below starting from the left:

Stock '77 280Z, '91 KA24DE, stock RB25DET, Toyota one



Vehicle Applications


1989 - 1998 Nissan 180SX (S13) L4 2.0L SR20DET

1991 - 1994 Nissan 240SX (S13) L4 2.4L KA24DE

1989 - 1993 Nissan Silvia (S13) L4 2.0L SR20DET


all the same.

Link to comment
Share on other sites

Cheers for sorting this out Stealth Z. I found the Toyota crossover part number for the one that was stated originally on Chris's brilliant thread - I then ordered it but found it was too thin. I thought the slimmer sender must be one that fitted an RB25 and not my RB26. I then became too busy to follow it up but have wanted to. I will give your suggestion a try asap.



Link to comment
Share on other sites

Nissan parts in Australia told me that the 2.4 came in the


Nissan Pintara U12,

the Nissan Navara Ute D21 and

the Nissan Bluebird U13

in Australia


I bought the sensor yesterday Nissan Part No 25080-89907, it has the number 7H stamped on it versus the RB26 one which has 9L stamped on it. The new sensor is the one on the right side (The middle one is the RB26 original)

Hope I have the right one. I will check the impedance later and advise.

See attached photos.


The sensor on the very left is adjacent to the water temp sensor on the RB26 - does anyone know what this one is for? Is it some water temp sensor back to the ECU?

H20 Temp Sensors_thumb.jpg

H20 Temp Sensors2_thumb.jpg

Link to comment
Share on other sites

My brother just tested the sensors I had:


Cold Hot (ohms)


The 240Z water temp sensor 0.3840 0.059


The Bluebird water temp sensor 1.192 0.166


The RB26 water temp sensor 0.485 0.065



The other RB26 sensor (very left photo above) 2.23 0.55


So maybe I bought the wrong sensor as the Bluebird sensor which is the one I was told was the same as the 2.4 motor is miles different to the 240Z original sensor, yet the RB26 original sensor actually isnt that much different - see ohms numbers above.


So question is - Is the 240Z sensor and gauge different to the 260Z sensor and gauge?

Or alternately have I just been given the wrong sensor (Nissan Bluebird) compared to the one Careless has used?


Any ideas Careless? Can you find out what the Nissan part number is of the models you mention - is it different or the same as the part number of the sensor I have bought?


Anyone - I know the 240Z & the 260Z gauges are different in their look and body - are the sensors different - I have a 2.8 motor in my 240Z and the sensor is the 240Z one I think (has a blank sensor with a nut that slides over it and screws into the thermostat housing)

In my 260Z I also had a 2.8 motor but the sensor which did run my 260Z gauge ok, screws into the thermostat housing but has a plastic like tube coming off the back of it? I will post some photos tomorrow.


The plot thickens

Link to comment
Share on other sites

J I had a '91 240SX KA24DE on an eng stand, and sure enough the sensor matched size and style. Taking a multi-meter to it, it had the same resistance at ambient temp and the orig Z sensor.


Stealth Z - Can you remember, or retest what the resistance was on the original and your replacement sensor to see if it matches the numbers we got above?

Link to comment
Share on other sites

Mike, just thought I'd repost that the sensor may FIT the 2.4's that you have there, but the dash guage operates on a different resistance range.


It's the 2.4 litre sensors we have here that use operate on the same range as the SR, CA and KA engines found elsewhere.


It could be possible that the engine is exactly the same in AUS but the guage cluster is differen.

Link to comment
Share on other sites

Mike, I'm assuming when you said ohms, you meant in thousands?


The larger one with the plastic sleeve is (I'm pretty sure) the one for the ecu. There were two sensors, one for the ecu and one solely for the gauge on the dash. The ecu one has two small leads instead of just one large, right? When I went to get that 240sx sensor, they tried to give me the one like yours but I had to insist that I needed the sensor specifically for the gauge. The threads and size except for the head looked the same, but I was unsure of their rating. By your readings it looks like the ecu one is more sensitive. And my findings on the rb vs. z sensors were similar in that the difference between the two was ranged, at least 30 ohms hot and 100 ohms or so cold, so using the rb sensor wouldn't be very accurate.


I put my z sensor and the 240sx sensor on the stove today. At room temp they read identically, 330ohms or something like that, and at 180F they read about 45ohms, and were within 5ohms of each other, which I figure is simply the margin of error.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...