Hi all, newbie here

 

Ok i'll list what i've got then tell the problem.

Rebuilt engine

new water pump

nismo thermostat

AMS pully kit, under driver crank,p.steeringand alternator with over drive water pump

Z-Centre electric fan kit

Defi blue gauges, water temp, oil press and boost

555 injectors

Z1 intercoolers

Z1 Howe Rad

Upgraded turbos, about 22 psi. Running boost jets at 14.5 psi

and JWT Air filter.

 

Problem is it's running really hot, and once the elec fan kicks in at 85 degrees it don't turn off. It'll go as high as 215F ( gauge is in fahrenheit ) 101C. If I turn the heating on in the car full blast I can knock 15F off the gauge. The fan is sucking air and it is really hot the engine, almost burnt fingers. The wierd thing is the Aux fan has never come on even when the gauge showed 215F. Also the normal dash gauge for temp doesn't budge. sits just below half way.

now with the Howe Rad when driving at 70mph i'd expect the temp to be at about 170F (76C) but it sits at 185 (85C). now this is thebit that really concerns me. If i boot it at full boost, the temp jumps 15/20F them takes a while to come down again, 10 mins or so.

At first i thought the elec fan wasn't up to the job, then thought it shouldn't be needed when driving at 70mph. I'm starting to think the thermostat is dicky? anyone agree ? just thought i'd get another opinion before pulling it all apart. Or anyother ideas i'd be grateful.

I would take the thermostat out, stick it in jug of hot water and check it opens and what temp first off.

there should be a fan running from startup? the electric fan is auxillary incase the viscous fan hasnt enough power to cool the engine.

 

Target running temperature is about 80*c i believe.

and check the aux fan is working, on mine i test it with the conzult low/high speed to show it works (not that that means it would click in over said temp when needed but would hope so)

Hello mate

 

Mines simialr set up: zcentre fan kit, howe TT rad etc. And I have the same both fans will be running almost permanently. I have got the garage to check it but they are convinced that it is running within safe limits. You can test the aux fan y removing the temp sensor on the water pipes. It may be that your aux fan is duff. Are you running a standard ecu or aftermarket one?

Aux fan works, tested that by removing ecu temp sensor connector. Running aftermarket ecu, it has JWT software.

Sounds like it could be a duff thermostat then but seems odd that its a new nismo one. Does your aftermarket ECU have a setting which tells the Aux fan when to come on?

I don't know if it does. but i shall ask the guy who did for me, just for piece of mind. Only since reading up tonight i realised the ecu controlled the aux fan.

I'm getting nissan thermostat on tuesday, so going to fit that next weekend. Along with the standard fan setup. Just to see if it brings the temps back down.

The other reason i think it's running to hot, forgot to mention this , is that when i turn it off i can remove the key from ignition before engine shutsdown, which isn't right.

Is that because you have a turbo timer? as this will keep the engine running longer and sometimes I can get my key out before it turns off.

 

As I said I have a similar set up. I think with the viscous fan which runs from the off it slows the engine building up heat as quickly but with the leccy ones it gets hot faster and so they kick in. Mine was staying on and draining the battery! I raised the temp of when it kicks in to about high 80s and it now seems to work alot better, I also have a Nismo thermostat so maybe this works to higher temps? the guys at the garage spen some time finding the aux fan setting on my AEM but it now seems to be on as soon as Ive been going 20 mins? On my old TVR I had a two stage fan kit which ran slow all the time and fast only when hot? might be worth getting a switch fitted to the fans to be able to turn them on can't see why having them both running permanently would be an issue when on the move

no turbo timer, I just don't like the idea of it going up to 100c when it's normal running temp is 85c. Just had it rebuilt costing over £7K with mods. Don't want to do it again cos it's over heating. Just been reading the Aus forums and tt.net and it appears the nismo thermostat can be troublesome. It's coming out of my car for definate now. I'll see how hot it runs on another thermostate.

Let me know matey if you find it brings the temps down I'll ditch mine too

have you done water bypass, that helps bring the temp down abit

ChrisD, water bypass was supposed to have been done on rebuild, is there away to tell by just looking?

 

Radron, I will let you know. Hopefully will do it this weekend, though that depends on our lovely British weather. I'm also going to blow out the rubbish from the aircon radiator, alot of dead flies etc in there, so my thinking is it might be hindering cooling. Once done i'll post back here, i don't like the sound of yours either, appears to be running to hot to me, the Aux fan shouldn't come on until over 100C, ( correct me if i'm wrong ) which is way to hot.

Deffo something wrong, spec is not dis similar to mine and certainly teh same Howe rad.

I constantly run approx 76 - 79 degrees and going up to a max of 82 on real warm days and slow traffic. Though i don't have the Zcentre electric fan, if i did, it shouldn't even really be used.

Thermostat or air lock in system perhaps, easier to check the latter first before going to the hassle of changing the stat.

smithy

The coolant level hasn't dropped at all, check it every morning. Though one thing did happen which i wasn't sure about. I took the radiator cap off ( cold engine ) and turned on the engine, just to help get any air out of the system. But after about 3 mins, the water level started rising to the point it was going to over flow out of the radiator. I then shut it off. Any ideas what this means, wasn't sure if this should happen or not.

Whats the best way to clear an air lock smithy

Dunno if it's the best way, cos i just have Zedworld do my stuff, :p

but if i was home i'd park her up on a steepish slope and release the air vent plug ontop of the rad. This should release any air in teh same way a house radiator does. Run it and add water slowly through this vent until yer happy.

cheers

smithy

Not sure on the bypass was done for me but looking just under the plenum i have some open small metal pipes.

Maybe im lucky my rad (if i lost lots of water doing maintance) sort of self bleeds, when i think its full i slowly see blows coming to the top and refill again (while cold) and always keep the top up bottle with plenty of water. Then the next day (after a good drive) undone rad cap and pressure is there.

I just have a feeling its your stat, if it was me i would prob have a drive with it removed and monitor temp.

Thanks for the input guys. I'll get back to you with the results hopefully this weekend.

I'd be very interested to see if the thermostat cures your issues. I have a similiar issue with a similar build. Electric fan, 555's uprated tubs and how front rad.

 

It does sound like a thermostat problem, but if it's not that or an air lock, it's going to be pretty hard to figure out what is causing the problem.

Also - welcome to the site mate. Nice to see another local (to me!) on here too. If you ever need a hand with anything, give me a shout, because I'm just down the road.

Are you running a oil cooler? I had similar problem with my car when first had the engine build and when through a mirriad of changes to try and resolve it. First being Scrapping my aircon Rad and system. Then going for a McCulack Racing Rad from SPL. It makes the Koyo rad look peuny. Then I went from a 15 row oil cooler to a 24 row cooler. Only when I blanked of the standard 10 oil feeds and got a remote filter plate and take off plate and piped it to the cooler in 22mm pipe did it solve the problem. Which was being caused by the heat generated by the bigger turbos and the higher compresion.

 

Once done the car was running too cool so the introdution of a Thermostatic valve return on the cooler feed finaly solve the problems. I then returned to a 15 row cooler and re introduce my aircon Rad. Oil temp only ever got to 110c after a severe thrashing from Tenby in South wales upto Chester Via a redlinine drive though the welsh A roads.

 

The other thing you should check is is your timing set properly. Even phil a C & S Wood got mine wrong because he was unawhere that his gun was faulty

 

Ps the other thing I've seen on two of my Zeds now is numties who are supposed to be knoledgable mechanics putting the thermostate in upsidedown which doesn allow the small amount of flow through required to get the hot water from the engine to the thernostate bulb quick enough to open when it should

 

+if its a genuine Nismo Thernostate it will open fully at 79c not 84 as with the OEM and your oil temp should normally be about 10 c hotter.

Edited September 1, 200817 yr by markzx

i have the following coolers in order front to back:

Auto oil

Power steering

Engine oil

air con rad

and water rad

 

all standard except auto cooler and the howe radiator. I have good oil pressure at cold ( 60psi) and when very hot at idle its at 25psi. Unless i'm wrong i don't think my oil is cooking otherwise i'd have a low psi when hot.

Interesting what you say about stat being in upside down. Didn't think they could but will check that out when i take it apart at the w/end. I have turbo dynamics 360 degree bearing turbos, i'm told can do 22psi. As i'm only running 14.5 at the mo the oil shouldn't be getting that much hotter should it ? Even then i'm only using in quick bursts as it's still running in. I've done 1000 miles since rebuild so only just started to give it full boost.

Hey Mark

 

OK this has all got me worried now. I had an oil cooler fitted where I didnt have one its a Z1 job. What are the changes that are needed to the way its fitted that I need to make. Thanks

Well I took mine out last night after about a month of not using it. Once it was warm I had a little play. I forgot to check the temp gauge for a few minutes.

I look up and it was sitting just below 250F :o.

 

Pul over and left at idle with the fan on while I opened the bonnet.... too late looks like the pressure already found it's way out via the gasket around the water pump.

 

Felt the rad and it was boiling hot near the water pipes, however the other side was stone cold.

 

I'll be stripping down the front of the engine at some point and changing the water pump and gaskets, hopefully it's not found another way out as well. I think I'll switch back to a stock rad cap/ thermostat as well.

Ok confused about the stat temps now, just got one from nissan and it says 76.5C, Would that be the temp it starts to open or the temp it is fully open? As Markzx states above the nismo fully opens at 79 and the standard is 84. Can anyone shed some light on this please?:confused: