Coolant temp / fuse wiring problem

[Forch77]

I just picked up my first Z last Thursday and since it has been raining all weekend I haven't had a chance to really do anything. The person who I bought it from of course said it was running and driving good I just needed a coolant temp sensor. So when I finally got it home I order the coolant tempt sensor and went for a quick spin around the block. The car wouldn't go over 20mph and it would sputter at that speed. So further investigation under the hood lead me to find this. (I've done research all weekend and haven't been able figure it out so any input is greatly appreciated)

Guessing glass fuses are supposed to go here:

Water Pump connections don't look right either:

Edited March 31, 2014 by Forch77

[Zed Head]

Those wires are called "fusible links", which I think is a translation from Japanese which could also be meltable wire. But the big red one looks like just regular wire built as a replacement. See the links below and look in the Electrical chapters.

I have to guess that you have a ZX engine with a Cylinder Head Temperature Sensor (CHTS), because there is no coolant sensor n the picture of your thermostat housing. Plus that "water pump connection" looks like a typical "thermal vacuum valve" from the ZX's. The sensors do the same thing, from different positions. Post a picture of the sensor you replaced, it doesn't seem visible.

Download an FSM from your year of car and read the Engine Fuel chapter. Download the Fuel Injection Guide from the xenon link and read it. Get a multimeter and a fuel pressure gauge and get some numbers. Adjust your valves and your timing, etc. Lots of fun things to do, each will make the engine run better.

Datsun Service Manuals - NICOclub

XenonS130 - S130 Reference

XenonS30

[EuroDat]

Welcome the world of Zeds

It looks like a 77 to me, but I could be wrong? Oil sender is pre 78 and the fuel lines along the frame rail fit description for 77 onwards. The vac thermo switch on the thermostat housing shouldn't be there. Did the PO change the housing with one out of a ZX?

Looking at all the disconnected wiring under the fusable links indicates he has been playing/removing and modifying stuff there too. All the A/C equipment and the vacuum acumulator for the idle are gone. The voltage regulator is gone or not connected, should be underneath behind the fusable links. He must have done the ZX alternator swap.

The fusable links don't look very good. You can buy fusable link sets and new cover on ebay. Dry the water out, replace the links and fit new covers. If they are cleaned, dry and corrosion free they should not give you any trouble.

Chas

Edited March 31, 2014 by EuroDat

[Forch77]

Zed Head: I would really hope it's not a ZX engine because it was sold to me as an "original motor" and it is a 77 (should have stated that sorry). But I was wonder where the vacuum lines are that go to the "thermal vacuum valve" but since this is my first Z I'm pretty clueless . But thank god you said this because I just ran outside to further inspect the engine and I've discovered two things.

Looks as if maybe he replaced it with a ZX water pump due to this blue "sealant" and these tucked away under everything!!

As far as me replacing the water tempt sensor it was supposed to come in the mail today so I haven't yet.

EuroDat: It is in fact a 77! I will have to order the fusible links/cover asap and get them all cleaned up. And it would appear that maybe he swapped a few parts from a ZX over to this not realizing the difference. As you stated with the alternator and how Zed Head pointed out the water pump, I think he may have swapped that over too. As far as the A/C its there but not hooked up and theirs a wire going to the pump that have been disconnected. I was on the fence about removing it all together, I might just have to go that route now..

Here's an engine picture for overall reference:

Edited March 31, 2014 by Forch77

[EuroDat]

I don't have many photo's of mine down the right side of the engine bay, but here are two which will give you an idea what has been removed on yours. The old voltage regulator should be under the metal beacket that the fusable links are mounted on.

You are missing some of the AC stuff on the left side and the idle servo unit on the inlet manifold is gone. I can see an AC dryer on the left side of the engine bay in your last photo. Maybe the PO rerouted a non dealer/nissan system?

Edited March 31, 2014 by EuroDat

[rcb280z]

Water and electrical don't mix. Please dry out the fusible link holders before you do anything electrical. That includes starting it.

A/C is definitely aftermarket.

As Zed Head recommended, get the FSM and read through it. It will give a better idea of what you are supposed to have. Then the forum can help you diagnose problems. Let see some other pics of her too.

Edited March 31, 2014 by rcb280z

[Forch77]

Water and electrical don't mix. Please dry out the fusible link holders before you do anything electrical. That includes starting it.

A/C is definitely aftermarket.

As Zed Head recommended, get the FSM and read through it. It will give a better idea of what you are supposed to have. Then the forum can help you diagnose problems. Let see some other pics of her too.

I haven't even put the key in the ignition all weekend because of the water getting on them. The passenger side vent I'm assuming is missing the under piece to keep the water out of the engine bay. (Had an Evo with the same style hood) A/C is going to go along with the fusible links. I've been looking through the "tech tips" EuroDat linked and I'm going to update it to a fuse box. As far as the FSM I tried to download the one that Zed Head linked but it keeps saying the compressed folder doesn't contain anything. I'll just keep hunting forms until I find another. I started an introduction thread in the S30 discuss area with some exterior pics. Here's a link:http://www.classiczcars.com/forums/open-s30-z-discussions/51933-another-new-z-owner-1977-280z.html

[Zed Head]

The nicoclub links aren't compressed. Open the 1976 or 1978 engine Fuel chapters. Whoever did us all a huge favor copying all of these FSM's copied all of 1977 in to one huge file. The others are split into chapters. The xenon files are zipped, so you would need an unzipping program.

Look between the first two spark plugs, at the bottom of the head and see what is molded there, It should say N47 but might say N42, P79 or P90.

I wouldn't worry too much about original engine. They're all very similar.

[Forch77]

The nicoclub links aren't compressed. Open the 1976 or 1978 engine Fuel chapters. Whoever did us all a huge favor copying all of these FSM's copied all of 1977 in to one huge file. The others are split into chapters. The xenon files are zipped, so you would need an unzipping program.

Look between the first two spark plugs, at the bottom of the head and see what is molded there, It should say N47 but might say N42, P79 or P90.

I wouldn't worry too much about original engine. They're all very similar.

Well it is in fact a N47 head and quick apologies for continuing to call it the water pump housing and making myself look like a total noob . I'll be ordering the proper thermostat housing this weekend along with all the new bits that go along with it as well as the parts for the fusible link upgrade. Hopefully this along with fresh gas, oil, and coolant will do the trick. Thanks for all the help guys and I'll update after I do!

[EuroDat]

The 280ZX thermostate housing on your engine will work, just need to change the vacuum switch for a thermo switch. It looks like the brown one, but smaller hex head.

The housing looks very dirty, but that could be only on the outside. Could be risky removing the switch to fit the other thermo switch. If you can get hold a new one for a 280Z would be safer.

[Zed Head]

EuroDat's talking about the fourth picture down in your first post. Take the lower left valve/switch out, the plastic one, it's not used on your system, and replace it with the new coolant sensor (if the threads are correct, they might not be). Your engine should not really be driveable at all without that sensor. The fact that it is means that it will probably run worse when you install it. Other things have probably been messed with to get it to run. One of those two plugs in your hand in Post #4 is probably the coolant sensor plug. It's supposed to be connected to the sensor. It's critical to proper operation. You have some work ahead of you. Those new parts will probably not do the whole trick but they'll get you closer.

[Forch77]

The 280ZX thermostate housing on your engine will work, just need to change the vacuum switch for a thermo switch. It looks like the brown one, but smaller hex head.

The housing looks very dirty, but that could be only on the outside. Could be risky removing the switch to fit the other thermo switch. If you can get hold a new one for a 280Z would be safer.

Jugding by the work the PO did along with the blue "liquid gasket" that leaks when the motor warmed up I'd feel more comfortable with just replacing the whole housing. That and the fact I was going to do a coolant flush I think this would be the better route. I am also going to replace the thermostat, radiator, and hoses to get rid of the 37+ years of gunk build up and hopefully prevent any future over heating problems.

EuroDat's talking about the fourth picture down in your first post. Take the lower left valve/switch out, the plastic one, it's not used on your system, and replace it with the new coolant sensor (if the threads are correct, they might not be). Your engine should not really be driveable at all without that sensor. The fact that it is means that it will probably run worse when you install it. Other things have probably been messed with to get it to run. One of those two plugs in your hand in Post #4 is probably the coolant sensor plug. It's supposed to be connected to the sensor. It's critical to proper operation. You have some work ahead of you. Those new parts will probably not do the whole trick but they'll get you closer.

Between the "test" drive I did around my block, the fusible links, and now knowing the car doesn't know how hot it's getting I haven't even started it. As far as the car being driveable, it does move on its own but thats about it. I wish I would have taped it and showed you guys the lap around my block it was horrendous. I've been reading through the Atlanticz tech tips write ups and looking at the diagrams and it has been really helping me out.

Thanks for all the help thus far guys I really appreciate it!