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logan66

New to Ratsun

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Hey guys, haven't posted on this in forever.  Been busy with school and other crap.  Anyways I've decided to go a different direction with the car.  I finally found a good deal for an l28et to put in the car.  Anyways I've ran into what i think is a potential problem that i think one of you might be able to enlighten me on.  So it look like there is an oil cooler adapter plate that goes where the filter should be.  Unfortunately it didn't have one on it when i got the motor.  I read that an oil cooler wasn't a necessity (which may not be true) but looking at the block with the filer goes. I see and inlet for the oil and the threads where the oil goes through the filter and into the block, the only thing ive noticed is there is no bypass for when the oil is cold.  The L28e has a little bypass valve where the L28et doesn't.  So my question is, did the oem sandwich plate for the oil cooler have a bypass valve in it?  If anyone has any info on this I would appreciate it because I can't find any solid info on this.

Thanks in advance!!

bypass_zps9x9rql6h.jpg

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Yes the sandwich plate had a bypass. You can run it without the oil cooler or get an aftermarket one. You can order the stud from online. Check MSA.

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Only the much later 280zx turbo automatic came with an oil cooler.

 

The oil cooler adapter is cast steel so maybe yours is some after market thing.

 

There is a small round ball with spring behind it in the block called a by pass, but is a safety device should the filter become blocked. The oil will force past the ball/spring and still lubricate the engine.

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I see what your talking about with the ball and spring by pass.  I have a pic of the l28e bypass but i guess i just dont understand where the bypass is on the l28et, can you not see it on that motor? It just scares me with that plug on turbo block where the bypass is on the other block. Is it physically in the block where you cant see it?  Basically i just want to know if i can buy the oil filter stud like and throw on a filter and still be safe.  Thanks for the info guys i appreciate it.  Also this is an 83 L28et but i dont know if it was from an automatic if that helps.

bypass2_zpsafgjolk5.jpg

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LZ23015Large-1.jpg

 

This is the ZX turbo oil filter adapter for the oil cooler. It only came on automatics. It does not have a 'by pass' for when the oil is cold. It is clamped to the block with a large hollow bolt in the center.

 

LZ23014Large.jpg

 

This is the oil tube than came on this Z22 block.

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So I started wiring up the FI harness today and realized that the harness the guy sold me wasnt the harness off of this particular motor.  Which is a bummer but thats my fault for not looking closer at it when i bought it. but is there anyway i can tell from the harness or ecu what year it is?  Also i ran into an even bigger problem the the FI harness that there,s no throttle position sensor on the harness and i cant find anywhere that looks like it was cut to be missing.  This is the plug i thought it should be but it doesnt fit the sensor, so maybe is there a different sensor plug in for the year of harness i have and motor if they are from different years.  I was following a thread on hybrid z that went through the wiring in fairly good detail but he was doing an 81 harness so mines a little different but everything was mostly the same up until this point of me not having the throttle position sensor.

 

sensor_zpszff1bdbk.jpg

 

heres maybe what i thought it should of been, it basically is the same plug as the fuel injector plugs and from the layout of the harness is kind of the right spot.  Anyway i have the right throttle position sensor plug that will fit from my 77 harness i could probably make use of if that is the case.  But any info you guys can give me would really help me out, Ive been on the internet all day today seeing if anyone has had similar problems but im getting pretty frustrated with it.  I also have a pic of the motor in the car, the motor doesnt really look nice but i thought it looked cool in the car without the fenders on it so im gonna post it anyways, again thanks guys!

 

in%20car_zpskmkuvgxx.jpg

 

 

 

 

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so i just found from the jecs number that the ecu is from an 82 turbo/manual so I would hope the harness is as well, if that info helps anyone. Thanks again!

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I mean really if you had to it wouldn't be horrible just making your own harness if you can't get something that'll work.

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You need the 82 280zx fsm and turbo supplement. Have a few hours with the wiring diagrams, and fuel sections. Its going to be really hard to get it running if you don't know what everything is, what you have or is missing. Everything you need to know is in there.

 

Does your engine have the CAS on the dizzy or on the front cover? If it is on the dizzy you "most likely" have and 82-83 engine. If it is  on the front cover, a 81 engine.

 

You can use the manual to locate the ECU connector pin for the TPS. Follow the wire from the connector and voila! You can use this method to find just about any connection to an electronic device on the harness.

 

I believe only the 81 harness used the dropping resistor pack, might want to double check, but the absence of it would let you know if you have the appropriate harness.

 

While you are at this stage, make sure you test all of your sensors and clean all of the connections.

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As far as the Factory Service Manuals go, 1981 had the suppliment. 1981 280ZX manual covers the non-turbo and has a separate smaller book for turbo specific parts as that is the first year the turbo Z was sold. Then in 1982 and 83 you have different chapters inside of the main book that go over the turbo related parts.

 

Not knowing the harness can be pretty bad. I would say that 1981 was the odd year and 1982/83 are the same for most everything on the turbo Z.

Mainly you'll find differences near the distributor. 1982/83 will have a round plug that connects to the distributor for the internal crank angle sensor. 1981 that plug wire is longer and goes down to the front of the engine where there is a large metal crank angle sensor.

 

All three years should have the same type of throttle position sensor and those sensors look the same as the non-turbo. I think the turbo Z lacks one switch inside. So the non-turbo has: Idle, off-idle, full throttle. The turbo Z might have idle, and off-idle only. (if I'm remembering correct)

 

What you had pictured in your hand looks like the plug that goes on top of the throttle position sensor and those two black wires look exactly like the ground wires that connect to any part of the top of the intake manifold.

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Thanks for all the info guys, it really helped my hands on the wiring diagrams.  I ended up just getting a Haynes manual for the 280zx turbo supplement. I have either an 82 or 83 harness because it doesn't have the drop resistor. And following the wiring diagrams from the Haynes manual the two little blue wires in the pics I posted above were for the tps sensor haha so I have no clue where the acutual plug went but it made sense because the wiring diagram only showed two wires headed back to the ecu from the sensor so ill eventually steal the plug sensor off my other harness for it.  Anyways I got the entire FI harness ready to go today and just started with the ignition side, but I ran in to problems with me not having this loom the guy talks about in the write up ive been following and also I didn't realize I needed the coil bracket from the zxt.  Anyways I looked them up online and they aren't cheap, so I feel like I should be able to make something work with my old ignition harness but its probably going to be a bit over my head so one of my dads friends who is a mechanic is going to come take a look.  He's a very skilled mechanic but I was just wondering if there's anything huge I'm missing that will cause me and him problems trying to make something out of the old harness and ignition parts?  From what I saw from the write up on hybrid z the guy wasn't really using much from the ignintion harness.  If anyone who knows of maybe problems we might run into trying to use the old harness or things to look out for I would appreciate it because it will help us both out.  But anyway thanks for all the help so far I got a lot further than I originally thought I would haha heres the post from hybrid z if anyone is curious to what im talking about with the coil bracket and stuff.

 

http://forums.hybridz.org/topic/38461-240z-260z-280z-turbo-swap-guide/

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Pro-tip: Don't let you mechanic friend tear up your harness. He's probably not going to understand the l28et wiring setup just by looking at it. You probably know way more about it than he does at this point.

 

You are defiantly going to need a l28et ignitor. A HEI might work, but i haven't tried it.

 

Really though, sit down with the harness and ecu, and go through the ecu pin-out diagram in the manual. Look and learn about the function of all of the devices and how to test them. If you try to short cut this you will have problems. Label all of your connectors and see what if any you are missing.

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Yeah that's a good tip lol there was a lot of stuff I had to explain to him and it was really unproductive but hopefully ill get this bracket with the ignitor soon.

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It's alive!!!! Had a couple hiccups with the wiring but it's all worked out now. I have a lot of work to do now to get this thing road worthy but hopefully it will start coming along faster. Unfortunately I only have weekends to work on it because I'm working in kc this summer and living at my sisters through the week. Anyways, thanks for all the help guys. Here's a link to a YouTube video of it running and a couple light revs. It sounds like crapt because I have no exhaust or downpipe for it right now lol but oh well.

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Man, that is awesome! good job.

 

What were some of the last things you did to get it running?

 

Funny thing is, I'm currently unable to get my 280ZX turbo running and right now I even left the engine in the original car. (parts car) No fuel, and possibly no spark. Really strange.

 

When your ignition is on but the car is not running, do you get 6v at the two plugs on the coil or do you have 12v ? Mine only has 6 which I thought was strange.

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Thanks! The very last thing I did was change out the fuel pump for a walbro 255 pump. Before that with the 40 year old stock fuel pump I could get the car to turnover but wouldn't idle. I had to hit it with a hammer a few times to get it to work so I knew it was about shot., I also had to plug up all the vacuum leaks on the intake. It's currently with duct tape so I'll need to do something a little less haggard later on haha. Are you taking about the the plug to the ignitor by the coil? I'll have to check when I go home this weekend, when I was doing all the wiring I was just using a test light but I'll look and see what I find.

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I didn't hear the fuel pump at all, so I replaced it with a Walbro. Still no pump noise and after all this cranking, the spark plugs are dry and still look new. I don't have a fuel pressure gauge but its safe to say no fuel is getting up there. I also put in a new fuel filter before even attempting a first start.
(drained the tank and put in 2 gallons fresh)

 

I'm talking about the two main terminals on the coil. They have small nuts that hold the wires down. Black is power, green is ground.

 

I'm collecting some ideas on what to troubleshoot next. I have to travel a distance to go work on the car so once I'm there, no time to get parts or tools that I didn't already bring.

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Well ran into trouble again lol I had my tach wire from the negative side of the coil setting o. The valve cover when I started the car this morning because I was going to solder the wire to the tach wire. So long story short I shorted the coil and it got super hot, now the car idles at like 1200 to 1100 rpm and idk what it could be. I switched the coil which I didn't think would change anything g and it didn't. I'm worried that it could of messed with the ignitor or ecu since the positive post is connected to both of them. Other than that I made a bracket for the afm and got a pod filter for it. I thought maybe the afm was touching the metal brackets and grounded it?? I took the brackets off and the idle dropped from about 1500 to where it is now. If anyone has any thoughts on what it could be because I have no idea what else to look for or try next. Thanks

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I guess I should also mention I shortened the charge pipe quite a bit between the turbo and afm. Idk if that would have any effect on anything

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idk what i did but its back to the normal idle  :confused:  so whatever i guess.

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The pipe between the turbo and MAF should usually be around 6 inches. The reason it has to be long like that is because it prevents turbulent air from the turbo hitting the MAF again. Obviously that wouldn't affect your problem but just figured I'd throw it out there.

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The pipe between the turbo and MAF should usually be around 6 inches.

It sounds like you're saying that the pipe between the two items should be at least 6 inches at a minimum, right? It could be longer and still function properly.

 

The same goes for the later Z with a MAS. The pipe between the throttle and the MAS should be at least 12 inches long so that the airflow seen by the MAS is a steady velocity.

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@Bleach

 

Yeah the minimum distance recommended is 6 inches. It can be way longer if you want it to be. I'm not sure how long the L28ET is but I know the pipe between the MAF and turbo on the RB25 is like 10-12 inches long.

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