Hey guys,my 300zx is leaking coolant again ive done the water pump,coolant bypass under the plenum,heater core bypass and now it started leaking again its leaking coolant from behind the plenum when i fill coolant up it comes out straight away i also dont need to start the car up for it to leak its also a quick leak ive spent over 1k to fix the coolant leaks but everytime i fix one thing it just starts leaking from a different place,would any one have any idea what it could be? Thanks Joseph
All your hoses are ancient, the pressure always breaks the weakest link so you only pop one hose/gasket at a time. You'll eventually change them all and if you've done it right they'll be good then.
I know my turn will come,when it does motor out do every hose I can see. If I don't there will always be doubt. Its the only safe way,but yes I know cash is the decider.Good luck
It will be a metal tube or a rubber hose. Why on earth didn't you check all the coolant hoses & pipework when you had the plenum off. This is a typical result of not paying attention to details. If it turns out to be a metal coolant tube/pipe that has corroded, it is possible the core plugs could be in a similar state & that's not good at all.
Yeah i was thinking that too and i had a mechanic to do the plenum pul for the bypass and he really didnt tell me anything is rusted but when i look at the back of the engine most of the pipes are rusted
Thank you and im honestly kicking my self next time definitely the engines coming out and im getting everything at once
A pressure test will help to locate the leak. A pressure test on re-assembly would be a good investment.
Just saying a pressure test can start a new leak,yes I know it will find it but good chance get extra, if in doubt run 13 psi rad cap will help give you time to save up to do every thing right.My TT has know leaks yet but I changed cap to 13 psi not a problem runs 182 on gage all the time or less.But warning a lot of 13 psi caps are not good sealers,so when you fit a new cap apply hand pressure to top hose listen for air escaping from new cap:rolleyes2:
That's kinda the point... Considering the cooling system can be pressurised with the plenum off (once the initial bypass has been done) you can potentially save a lot of labour by testing prior to reinstalling. Running a lower pressure cap actually reduces the efficiency of the cooling system; I don't think this is a good substitute for maintenance.
Please read all that I said,we can if and but or what all day,my offer above is to keep him on the road till he has the cash to do it all the right way.Not a thing will out do brand new,i know this to well but I have seen how hard it can be for some one that cant pay thousands straight up :br::zlove: Happy Z sunday all:rolleyes2:
Even running a lower pressure cap pressure testing it to that level would be quicker than assembling, test driving up to temp then pulling it apart again.
Here's the deal with metal coolant tubes & core plugs. If they are corroding, they are corroding from the inside to the outside. Even though a tube or pipe is corroded it can appear OK externally. I would not recommend replacing the radiator cap with a cap with a lower relief valve pressure.
Has not hurt my Z and a car even a z will run all day with no psi but what do I know only been around cars bikes 60 years,a lot of think they know it all on the net.But that's life :rofl:
Lol, ECZ is qualified mechanic, probably fixed more cars in week than you've owned so you probably want a different draw card. Truth is most Zs around are already struggling with sub-par unserviced cooling systems, reducing the performance even further is hard to recommend. They'll run fine at 95C on the daily but doesn't leave much wiggle room if you start to push it harder or something else fails.
