My car got pretty hot last night (not to the H only top of the bar) when I checked I found the resevoir bottle leaking, so took it to the Radiator place and pressure tested it, all the water came pissing out the back of the motor somewhere, my mechanic wasnt interested in doing the job because the top all had to come off(too big for a small job) he suggested taking it to Nissan because they will have all the new gaskets etc to do the job. Does anyone have any experience with these hoses, and can I do it myself without too much difficulty.... It happened just after I turned the boost back up to about 14psi on a long run, I dont know whether this has any bearing on it or not !!!
If it's heater hoses needed that's easy. RHS turbo hose also not hard, LHS a pita. Underplenum hoses may be bypassed without plenum pull if you know what you're doing.
none of these leaks are easy. There are a few possibilities. 1) The hard pipes that go to the heater are corroded through, (gearbox out to fix) 2) Rubber heater pipes are leaking ( hard but doable from the top) 3) Turbo feed rubber pipes have failed, (Possibly doable from the top but easier with upper plenum off) Iikely Item 1 or the bastard hose on the left or right side going to turbos. Its a reasonably biggish job. Suggest UAS or another zed specialist.
I'll try to identify leak Thanks, I will try to find where the leak is coming from if possible, the problem is it is so tight in there and so bloody low from underneath !!!
Just above join between motor and Gearbox It looks as though the leak is coming somewhere behind the motor low down very close to the connection between the motor and the gearbox, cant exactly see it, but up high the motor looks dry, it may be slightly towards the drivers side!!!How many outlets are there for the water, I might be able to rule them out one by one !!!
i agree, dont bother picking, just pull the plenum and it will be obvious, then replace all other dry/brittle/old hoses you can find
Yup what the others have said.. do a plenum pull.. i put off doing a plenum pull and kept replacing little hoses one after the other... it got to a point where i was so frustrated that i decided to do the plenum pull... that way u get all those little buggers.. theres heaps of post on what u need to buy for a plenum pull and how to do it.. just search it it's gonna take time and GOOD/RELIABLE tools... but worth the piece of mind
Pull the plenum Do a hose bypass or take it to a reliable mechanic like UAS or others before it costs you heaps to get the above done. :zlove:
Leaking between manifold & Plennum The leak looks as though it is coming from underneath the monifold and plennum, got to get the manifold off, will replace rear pipes as well as the thermostat. Will check to see if timingbelt has been changed at 100k. I've just bought the car and it has done 115k. Whats involved in removing the manifold and possibly replacing the timing belt whilt I'm at it. What is th pipe that goes under the manifold made from ? Can it be repaired or does it need to be replaced ? How much does a new timing belt cost and is it time consuming to do? Thanks for everyone help!!!!
It's all aluminum or alloy of. Plenum off first time = about 3-4 hours, as there are so many thing so detach. On reassembly, a lot can be left off (esp water hoses aka bypassed) 100K service under $800 for parts I believe (See caz1 on this forum), and maybe around $900 for a mechanic to do in labour (prices and hours may vary). The water pipes/hoses under the manifold (Plenum) are a labyrinth of metal and rubber sections. These can be removed and bypassed so as to not create weak points in your cooling system to re-manifest themselves later on (Piece of mind)
Which pipes to bypass Ok, sounds like a good idea to by pass these pipes if they are not needed, but which pipes are they and what do I do ????? I want a good rock solid cooling systm to start any future mods lter on. If anyone has a pic of the pipes or hoses it would make it so much easier. Thanks heaps.....
You just basically take out the loop of coolant lines that run under the plenum and replace it with a length of hose(s) across the back of the motor
um if its a heater hose they arnt that hard just akward so yea i did mine myself. you should be able to see if it is so just have a good look around there
A Bit Contrversial here but ... Mate, If you have leaking hoses under the plennum then just replace all of those hoses, why be a smartass and bypass them. Just replace them and they'll last another 15+ years. If you own the car after 30 years and have to replace them again, I guess you'll be an old bugger with dementia, in which case ... Hello, this is a NISSAN 300ZX !! I just relaced all hoses in the Godfather, just before COWRA at Easter. It costs about $6 in hoses - 8mm low pressure hose. Easy and effective. I just don't understand the benefit of a bypass. Why be clever just for the sake of it, just replace the hoses 1 for 1. It's no extra effort. btw I'd also recommend replacing the 2 heater hoses - cost heaps, can't remember if they're total of $100 or $100 each, but this makes a plennum bypass cost insignificant. Of course, all costs exclude labour. Cheers, Peter
Timing belt whilst Im at it??? What else should I be looking at whilst the top is off the motor and access is easily available ?? Eg Timing belts, etc, Im not sure about the history of the maintenance on this car although it seems good I think if I can just check a few items while I'm under here it might be wise!!! What should I look at ? and what should I replace ? Whats involved and HOW MUCH DOES IT COST ? I plan to start today...
