2JZ over heating problems help please??

[the fallen303]

1j and 2j water pumps are almost identical, so shouldn't be an issue.

turbo's on our aristo switch over at about 3500, but as you're not using the 1st turbo to help spool the 2nd, so it's just running true twin, they may come in a bit later?

the stock front bumper shouldn't be an issue until you start running serious power through it, and even then it's not too bad. plenty of high hp cars in japan/usa that still run stock front bumper.

[mjrstar]

have you checked the ignition timing?

[Girvs]

1j and 2j water pumps are almost identical, so shouldn't be an issue.

The GE's and GTE's are different for the 2J, so I wouldn't be surprised if there was some variation between the 1J and the 2J

[trd-drifting]

The GE's and GTE's are different for the 2J, so I wouldn't be surprised if there was some variation between the 1J and the 2J

Im 99% sure it should be fine but the pump was brought from toyota as a 2JZ pump i put on my 1JZ to get rid of the hydro fan setup as i don't have a hydro fan and they are so bulky as well. Lots of people change them over and do not have any problems. Also i changed the pump on my 1JZ just before i broke it, and it wasnt sitting around for long and bearings are fine and there has been no rubbing etc..

[trd-drifting]

thanks for that John sounds about right then i guess boost wise i was just curious.

have you checked the ignition timing?

Ignition timing is all electronicly controlled by the link and i think brent at tunning and performance would of picked that up on the dyno, but I know when like you exhaust cam timing is retarted that can heat up the car more than needed due to the exhaust gases hanging around for longer i think. But cambelt and cam timming is all fine and it is all standard at the moment.

[2jayzgte]

How can i make sure there is no air locks or bleed it correctly? wouldnt 500kms of normal driving force the airlock out due to the coolent expanding?

Also what rpm does standard 2JZ turbos kick in as it seems a lot laggier than my 1JZ. I have removed all the little valves and solonoids and the butterfly valve in the intercooler piping so both turbos spool at the same time. Full boost (12psi) took till 3600rpm according to the dyno charts and im sure my 1jz was like 2800rpm.

Josh

If in sequiential mode you should see boost at 2000 rpm and if you have a EBC setup or not you can have a max boost of whatever as soon as both turbo's come on line which should be at about 3700 rpm.Without EBC in place the boost should be linear and you won't see the factory 11 psi until after 5000 rpm.

[the fallen303]

The GE's and GTE's are different for the 2J, so I wouldn't be surprised if there was some variation between the 1J and the 2J

Im 99% sure it should be fine but the pump was brought from toyota as a 2JZ pump i put on my 1JZ to get rid of the hydro fan setup as i don't have a hydro fan and they are so bulky as well. Lots of people change them over and do not have any problems. Also i changed the pump on my 1JZ just before i broke it, and it wasnt sitting around for long and bearings are fine and there has been no rubbing etc..

sorry guess i miss worded that one girvs. there are differences in pumps due to application, what car they came from, ge or gte, and wether the system runs a hydro fan or not, but the actual guts of the pump is the same, still bolts to the block the same between the two, and still does same job. it's just external differences.

the pump i have on my 1j is listed as being from either a 1jz soarer, or 2jz mk4, lol

[YeMs]

have you checked and double checked that the fan is blowing the correct way? i have seen it time and time again. people come in with an over heating car, especially those dope skyline/cefiro/laurels that people put the big alloy cores on and they wire the fan backwards.

using your hand is not good enough, because u can mistake fan air draw for pressure.

u need to use a piece of paper and see if the fan 'sucks it' onto the radiator (or in your case, sucks it onto the fan)

also, is it definately over heating? i know that using the wrong temp sender for the link ecu's or not having the ecu calibrated right can cause it to read wrong and seem is over heating.

i had issues with my 2jzgte in my cressida. i had the standard cressida radiator, twin fans, and a 700x600x120 intercooler infront of it, a huge unit, i thought that was the issue. but it came down to not having any coolant in the system (as i had just got it all running and hadnt had a chance to flush it with coolant) and only a 13psi cap. once i fixed them it was sweet. about 30 dyno runs. 3rd gear linelocks over 300 metres long before the temp would start climbing.

and also, the water pumps are the same. i ran a soarer 1jzgte waterpump on mine.

[trd-drifting]

have you checked and double checked that the fan is blowing the correct way? i have seen it time and time again. people come in with an over heating car, especially those dope skyline/cefiro/laurels that people put the big alloy cores on and they wire the fan backwards.

using your hand is not good enough, because u can mistake fan air draw for pressure.

u need to use a piece of paper and see if the fan 'sucks it' onto the radiator (or in your case, sucks it onto the fan)

also, is it definately over heating? i know that using the wrong temp sender for the link ecu's or not having the ecu calibrated right can cause it to read wrong and seem is over heating.

i had issues with my 2jzgte in my cressida. i had the standard cressida radiator, twin fans, and a 700x600x120 intercooler infront of it, a huge unit, i thought that was the issue. but it came down to not having any coolant in the system (as i had just got it all running and hadnt had a chance to flush it with coolant) and only a 13psi cap. once i fixed them it was sweet. about 30 dyno runs. 3rd gear linelocks over 300 metres long before the temp would start climbing.

and also, the water pumps are the same. i ran a soarer 1jzgte waterpump on mine.

Fan is deffintly running the right way, I have considered that but not fully eliminated that yet but pretty sure it is fine, when the lap top is pluged in the gauge reads the same as the ecu, and the thermography gun ran 1 or 2 degrees difference between that and the radiator. I started off with using a coolent mix, then ended up trying water as i have removed radiator several times now didnt want to watse the coolent. but both ways with and without coolent still over heats, btu coolent shows up dirty so deff must be a block some where even tho i have by passed my heater core it still over heats.

[trd-drifting]

I removed a few frost plugs tuesday night and coolent in block was perfect colour even tho that the coolent by the thermostate that came out was rather dirty. Will remove one closer to the back of the block sunday when i have time. Cudn't pick up any crap off the bottom of the gallieries etc, with a piece of tig wire.

Any other checks i can do while the cambelt water pump etc.. is off as most things are easyish to get to? And do not want to have to remove it once more just to check things. I will have a look with our snake thing from work, camera on a flexiable lead with light around the lines of the block just to completly satisfy my self they are not slightly blocked, anything else before i put it back together? Maybe pass compressed air through all the lines, and double check the roughting of them with diagrams agian, sure they are all fine tho as it is rather simple.

Josh

[strx7]

possible attach the 2 radiator hoses to the block attach a garden hose in direction of normal flow and turn it on high for a few mins. might be enough to force any air locks out, will also clear out some of the brown crap

[allencr]

I removed a few frost plugs

The heat comes from the head, the combustion chamber & exhaust port, comparatively little from down below.

What's the temp difference between the upper & lower, in & out radiator hoses?? It should be a Minimum of 10C, else the rad isn't doing its job.
Any modifications, tricks or special speed secrets done to the stock cooling system routing?
From the upper hose the water pump should put out a solid stream like a fire hose, same as the hose ID, for about 1m long when the thermostat is removed and the engine is reved up.
Any & all air gets purged once the thermo. opens and its rpm is over 3000.
Heater hoses looped, then it's bypassing the radiator?

If there isn't any combustion gas getting into the coolant and the pump flows well and the radiator flows well, then air isn't flowing through the radiator.
Good luck.

[rollaholic]

'coolant' is no better at cooling than water, by the way.

[sergei]

'coolant' is no better at cooling than water, by the way.

It increases boiling point, although it lowers the specific heat the benefit is a lot greater, as when the water is boiling it can take away great deal of heat, it also creates steam pockets and is a very destructive way to cool a system that was not designed for boil.

[rollaholic]

the difference between pure water and half antifreeze half water is only a few degrees though. similar to what you gain from pressure increase from rad cap. my point was that antifreeze, or lack of, is not going to be the reason his car is overheating

http://en.wikipedia.org/wiki/Ethylene_glycol

interestingly pure antifreeze looks to have nearly double the boiling point of water. it freezes alot more easily than a mix, though i doubt that would be a problem in most places in NZ. do you know anything about its capacity to store heat energy? i presume its less efficent than water in that respect

[sergei]

2.394 J/(g K) for e.glycol
vs
4.18 J/(g K) for water

[strx7]

I know it is reccomended for R32 GTR's to run 100% water for track days on std radiators.

Do i read that right that water nearly has twice the heat transfer of anti freeze?

[sergei]

I know it is reccomended for R32 GTR's to run 100% water for track days on std radiators.

Do i read that right that water nearly has twice the heat transfer of anti freeze?

2.394 J/(g K) for e.glycol
vs
4.18 J/(g K) for water

Heat capacity .

[trd-drifting]

Hey i am bringing up this subject because i have never sorted it out, and the fact i crashed my car and bent the chassis straight after the last post, and never wanted to look at it after that for a long time. Now i have a new shell + cage etc so its already for the motor to go in.
So now i have pulled the head off, every thing seems to be fine, head gasket has not leaked etc... All holes were punched out in gasket, no holes were blocked off etc...

Since the head is off what else can i check on the block, before i prep the block and head and put a new head gasket on?

Basic things like:
its is straight
no oil in bolt holes
Flush it out clean out water gallerys (they are not to bad)
Measure bolts that they are not to long and bottom out

What else????

I do not want to put the head back on and it still over heats and find i have missed checking somthing out.
Note: before i removed the head i did find a kinked heater hose line which i do not think is the root cause of the problem but defintly is adding to it. Cannot believe i did not see this in the car. water still runs through it but just.



Uploaded with ImageShack.us

[deaf_rattle]

The headghasket is probably still leaking because the block wasn't "decked".

Pretty common on JZs if you talk to an engine reconditioner.

Steve

say what?

lol, always one. block surface isnt so important with stock non metal headgasket (but id say 2jzgte runs mhg?)

Ewan had over heating problems with his 1uz in ma61 and it turned out to be one of the rear fittings (heater line) nothing being able to flow enough water through the system.