HELP!!!!! coolant/radiator leak. HUGE STEAM COULD

[Ricardosaurusrex]

So this morning i warmed up my Z everything working fine. I am a block away from work and suddenly a huge plume of white smoke starts coming out of my car. its not coming out of the exhaust so i figure its a coolant or radiator leak. i open up the hood and again, more white smoke (i assume its steam) comes out. its coming out near the back of the engine.

Ive searched this forum and the concensus is that yes, this in fact is a coolant leak. my question however, is a three part question.

1.) does this mean i have to pull the plenum? i have never done this so perhaps someone can direct me to a link that could explain the process. i am a visual learner so pictures help

2.) i have read that if you have to replace one hose its best to replace all the coolant hoses, if so, where can i find a complete hose kit for my tt Z. id like to just have all the hoses in one nice kit.

3.) i have found some hose kits on ebay however not sure if these are worth their weight in gold or just their weight in feathers. please let me know. i would really like to get this project done by this weekend.

Thank you so much for your help.


here is a link to the ebay item: http://www.ebay.com/itm/27PCS-silicone- ... 344wt_1126

[NolimitZ32]

1. most likely

2. absolutely, its a PITA to do any of them so replacing all of them together is best

3.can't look at the link but I am a fan or going with either OEM or stuff from Z!, CZP or SZ.

[Ziggy1621]

You need to find exactly where the leak is coming from before you start pulling stuff. Fill the radiation, put it up on jack stands or something of the like and start it up, keep a flash light handy.

Also, moving this thread to Tech

[Ricardosaurusrex]

So I did as you said ziggy, and the leak doesn't seem to be coming from below and it's a bit hard to tell where it's coming from since the transmission blocks the rest of my view up.

Thanks for the quick reply nolimit. I was wondering if you had a list or maybe part number of the hoses I need for under the plenum as well as other things I should go ahead and replace while I'm under there.

Thank you so much you guys have been very helpful.

[ThisIsSparTTa]

Everything you need to know: http://z32.wikispaces.com/Intake+Manifold+Removal

[Ziggy1621]

So I did as you said ziggy, and the leak doesn't seem to be coming from below and it's a bit hard to tell where it's coming from since the transmission blocks the rest of my view up.

Is it pouring out? The reason I said get it up on jack stands is so that you can get under it with a flashlight. You may get wet, but if you do it while the car is cold, you will be able to see where it is coming from. Again, don't just start pulling parts until you KNOW where the leak is coming from. If you pull the plenum and do not see the leak, you can't just crank the car with the plenum off If you have a radiator pressure tester, you could try that as well.

[Ricardosaurusrex]

Thanks for the link, it really helps.

Ziggy, I did as you said I lifted the car checked under with a flashlight and am unable to see past the transmission. I turned the car on and let it go until it started leaking. The leak is coming from above the transmission. Not sure where or how to see where it is coming from. I know it's a coolant line Cuz when I go to check my radiator it is empty. I refill it turn the car back on and check for leak tests. I'm not sure how else you would have me locate the leak without removing any parts. I am still open to suggestions, so please keep them coming. Perhaps if you have a link or a video showing me how it would make things a lot easier. Thank you so much guys you have been most helpful.

[Metacom]

There are two metal coolant pipes with connecting rubber hoses (short ones) right above the EGR. One may have split on the under side. Find the highest point of where everything is wet and the leak will be in that area.

Check your water inlet and outlet pipes to your turbos for cracks/loose fittings.

[Ricardosaurusrex]

awesome, does this require a plenum pull or would this just be checked by removing the balance tube/connections near the back of the plenum? thanks, wonderful advice.

[Ricardosaurusrex]

Im located in san jose, anyone that has done a plenum pull interested in helping me this weekend? i dont have much money but you get all the beer you can drink and all the ribs you can eat pm me if you are interested. id love to get thsi thing done, also contemplating the idea of doing the coolant bypass however im a bit aprehensive about all of this so if there is an experienced person here that would be willing to lend me a hand i would appreciate it.


Thank you!

[po8pimp]

use flour to find the wet spot :P

[po8pimp]

no for real though http://www.youtube.com/watch?v=FgCLGXTlim0 all you need. This guy is so weird sometimes.

[Ricardosaurusrex]

Thanks for the advise. I picked up the leak test out last night. I have been reading, and some ppl say that it might be the heater core hoses, is this a possibility? And in the event that it is the heater core hoses, how would I reach them? Would the plenum pull be enough or would this require reaching them from underneath via transmission drop? I found a post where someone mentions the absolute and only way to reach those hoses is by pulling the engine, how much truth is behind that post?

Thanks again for all your support.

[nissanfreak12]

The heater hoses can be done with pulling the plenum, and could be a possibility, but its a PITA. The turbo cooling line on the back side of the engine needs at least a plenum pull, dropping the transmission would be optimal, but can still be done with just the plenum pull. Its tough, just take your time.

[Ricardosaurusrex]

phew! thank you so much i was sweating the big one. thank you very much for that wise insight. i will be replacing all my hoses this weekend. per nolimitz im going with z1 performance parts. thanks guys for all your help.

[Metacom]

The two coolant hoses on the back and above the EGR can be replaced without pulling plenum. I watched a Z shop do it. It took them 1 1/2 hours to get it on and a lot of frustration. Also lube up the pipes before you slip the hose on. You'll need a very long pair of needle nose pliers.

[Ricardosaurusrex]

thanks for the reply. it sounds like it would be much easier to just drop the transmission and work on them from underneath. with that in mind, can anybody point me to a good guide/tutorial on dropping the transmission and possibly also point me towards a diagram of the coolant lines?

Thank you

[Ricardosaurusrex]

forgot to mention, my car is an automatic.


Thank you!

[ThisIsSparTTa]

I really doubt you'd get a better shot at the coolant lines from the bottom. Taking the plenum off is going to be your easiest bet, and you can take care of some other common maintenance issues while in there, if you want: EGR removal, coolant line bypass, valve cover gaskets.

Also, getting the transmission off isn't a simple feat, especially your first time. With 2 people, and our 2nd time doing it, it still collectively took probably 3-4 hours, including all the other stuff that has to come off (exhaust, driveshaft, etc). Also, if you've had exhaust work done by a hackjob muffler shop where they welded everything together, it makes it even more fun.

If for some reason, you do decide to pull the transmission, take off the torque converter and do the rear main seal while you're right there. Its a very common oil leak point, and you'd rather not need to do the transmission twice. http://www.nicoclub.com/archives/rear-m ... ement.html

You could also consider getting a set of downpipes to replace your stock pre-cats while you're in there too, if they're not already done. But that's not maintenance work, and a good bit more money.

[Ricardosaurusrex]

thanks for the insight. I have pulled off other transmissions however not one on a z. i would still like to know how to do it. i understand that going slow and steady will be key in dropping the trany your first time. ive read several other threads where ppl say its a simple job but with no guide for the removal.

with that in mind, is there any article you could point me towards that describes the automatic transmission removal process? i would really appreciate that support.

Thank you

[t.mcginley.jr]

thanks for the insight. I have pulled off other transmissions however not one on a z. i would still like to know how to do it. i understand that going slow and steady will be key in dropping the trany your first time. ive read several other threads where ppl say its a simple job but with no guide for the removal.

with that in mind, is there any article you could point me towards that describes the automatic transmission removal process? i would really appreciate that support.

Thank you

Here's a somewhat how-to:

http://www.twinturbo.net/nissan/300zx/f ... ssion.html

The hardest parts of the job will be removing the bellhousing bolts and then getting the trans lined up correctly when you reinstall it. Some other tips:

1) drop the exhaust, either from the headers back or just the midpipes and H-pipe
2) remove the driveshaft (obviously)
3) drain the pan beforehand, IIRC there is no drain plug so just drop the whole pan
4) unbolt the torque converter from the flexplate, theres a little black shield between the engine/trans for access
5) you will need to either remove the cooling lines at the trans or at the radiator (if you do it at the radiator, I have no idea how you will get the trans out without messing them up)
6) remove the dipstick tube
7) you MAY be able to get the top 2 bellhousing bolts from the top (usually with the plenum off anyway), or use a 30-36" extension with one or more swivels on an impact gun from the back
8) don't forget to remove the shifter linkage from the trans, I honestly can't remember how but I think there's a linkage with some cotter pins
9) also don't forget to disconnect the electrical connections, there should be 2 or 3. I don't remember be able to get to mine so I remove the whole subharness with the trans (disconnect the other end from the alternator)

[Ricardosaurusrex]

awesome, thank you for this. really appreciate it. i will let you guys know how it went

[ThisIsSparTTa]

In regards to getting to the top 2 transmission bolts. Definitely recommend a 2nd person. For the one on the passenger side, you can get it on from the top, it either takes 1) someone with small hands that can squeeze through the AC lines and other BS there or 2) being very crafty and patient with a magnet, and screw driver. IIRC, you'll need 1, if not 2 U-joints to get it to line up. You'll need a second person under the car to turn the socket wrench.

I dunno how you would get to the drivers side from the top, there's just SO MUCH going on in that area. I put together literally ALL of my 3/8" extensions to make a roughly 3' extension. The key is socket>u-joint>~2" extension>u-joint>~3 feet of extensions>socket wrench. I really should have taken the picture of my setup last time I did it. You'll need 1 person at the bell housing to get and hold the socket on the bolt, and someone at the back of the transmission to turn the socket wrench.

http://zhome.com/ZCMnL/PICS/clutch/clutch.html

[Ricardosaurusrex]

I FOUND THE LEAK! so after much toiling and bruised knuckles I was able to remove the plenum. The heater core line had a sizeable hole and was leaking coolant. I also noticed that my EGR feed lines to the plenum were clogged, is this a common issue? Is this a sign of other issues I should address while the plenum is off? (other than coolant bypass)

Thank you, and thanks again for the transmission info just wanted ed to be prepared for the worst

[ThisIsSparTTa]

Delete the EGR, they're all clogged and not working. Do the coolant line bypass. You could have done your valve cover gaskets.

[Ricardosaurusrex]

Will deleting the EGR affect passing smog in anyway? To my understanding that's what they are for?.... Idk.

[ThisIsSparTTa]

Yes, it can affect it, if it was working anyways. It depends on how stringent your local laws are. If you're in California, they will actively look for it. In TX, not so much. If you don't have to pass smog, then you're all good!

[t.mcginley.jr]

Will deleting the EGR affect passing smog in anyway? To my understanding that's what they are for?.... Idk.

Yes, it can affect it, if it was working anyways. It depends on how stringent your local laws are. If you're in California, they will actively look for it. In TX, not so much. If you don't have to pass smog, then you're all good!

^This. It really depends what state you live in and what kind of testing (or lack thereof) they do. I can tell you that in NJ I passed emissions without my EGR valve. For reference, these are the times when the EGR valve is NOT operating:

1) Low engine temperature
2) Engine starting
3) High-speed engine operation
4) Engine idling
5) Excessively high engine temperature

It basically only opens up when you are cruising at a constant speed and the engine is fully warm.

More info about the EGR valve and why you can delete it: http://s95014253.onlinehome.us/63104/197828.html

[Ricardosaurusrex]

Thanks for the info. I live in California and they have started that whole state star testing thing. So for now I think I will keep the EGR system.

[t.mcginley.jr]

Thanks for the info. I live in California and they have started that whole state star testing thing. So for now I think I will keep the EGR system.

Oh yeah California you're at like ground zero for emissions testing haha. You have to keep the EGR valve then (they will still have a ridiculously hard time trying to find it). I would clean all of the crud out of the EGR tubes and reinstall with new gaskets. How many miles are on the engine? New EGR valves aren't cheap (over $200) but unless you have really high miles you shouldn't need a new one.