Overheating

[McNamara]

Hi Guys
I am a newbie to the forum and already wanting to pick your brains.
I have a TD42 1995 that has had a turbo and intercooler fitted. For the past 1 and a 1/2 years and 15000km no problems. Then she overheated and the head gasket went. This was repaired and 4 day later the same problem. Nissan found a crack in the head and this was replaced.

I was advised to upgrade the cooling system to cater for the turbo. I have fitted a 3 core radiator and removed the electrical fans and gone back to the viscous fan and shroud. The temp still moves between 1/4 and 1/2 so i had a Madman EMS fitted to get a better reading. Water temp goes to 114deg and then i back off and the oil does to 90deg. The EGT go to 350 and this is where i thought my problem was with over fueling but as far as I understand this is acceptable.

Can anybody give me pointers where to from here.

Many thanks

Wayne Mac

[Peter Connan]

Wayne these motors are notorious for overheating when turbo'd and (possibly) not correctly set up.

However your EGT's seem very low. Most guys struggle to keep it under 600 or so. Where is the sensor for the EGT located?

I would recommend speaking to Tour de Frans and also Pieter du Toit, who both have experience with this problem.

[Grant]

Wayne,


Disagree with Peter. These engines over heat when incorrectly set up with a turbo.Guys are trying to get too much power and hence the heat issue. I have a GQ 4.2 diesel, with 378k km on and to date no problems. I keep the Troll service and go through a maintenance schedule where I replace components before they fail. The Aussie form has a thread for overheating issues. Your egt seems very low. Mine gets to around 600 as a maximum. Many comment but the Aussie guys recon depending on whether you have a silver to or black top you can push to 700c. For safety I do not exceed 620C . My max coolant temp is 97 to 98 C. My suggestion is to look at the thermostat, water pump, radiator and viscous coupling.


Master Parts in Belville should have water pump for you.

http://www.masterparts.com/contact.php


I have always had great service from SAC, try Richard at SAC Capetown.

SAC Cape Town
450 Koeberg Road,
Milnerton, Cape town,
Western Cape, South Africa.
Tel: +27 021 552 1003
Fax: +27 021 552 3486
email: sacct@iafrica.com

[Peter Connan]

Sorry, phixed it. This happens when i am in a hurry and don't read through my posts a third time

But if you speak to Tour de Frans, he had serious overheating problems that he was never able to sort out. And Pieter had to go to extreme lengths to cure his problems, including adding bonnet scoops, adding an oil cooler and moving his air-con radiator underneath the car.

[McNamara]

Hi Guys
Thanks for the pointers.
I think i am going to do the water pump and then make a turn at SAC. All the other parts have been replaced. This weekend we went to Hermanus and again water temp was 115deg, oil got to 99deg and EGT max at 360deg. Grant where is your EGT sencor fitted. Mine is in the top centre of the exhaust manifold and maybe it should be lower down.

Thanks again.
Wayne Mac

[ricster]

Hmmmm... no you want that EGT probe as close to the heads exhaust ports as possible. Something sounds wrong with your EGT's only reaching 360deg C. I'm going to ask a silly question, but is your gauge set to Celsius? I struggle to get my EGT's to stabilize at 380deg C when on a flat highway without a head wind!!!!!! Mine can get to 620deg C by the time I reach the bottom of a highway on ramp, if I push hard.

I think your probe might be faulty, if your gauge is set to Celsius. This happened to me when I bought my Patrol. I would cruise on the highway and register 120 Deg C on the EGT gauge..... I quickly changed that !!!

Another VERY VERY VERY .....ummm.....let me say it again... VERY important thing to check is antifreeze (Coolant). Do yourself a favour, go to any Silverton Radiators, and buy 6 x 1l bottles or their antifreeze. Drain, flush, rinse well and slap all 6 bottles in and top up with good clean water. I think I paid R60 odd per bottle. The difference was quite something. Remember your Patrol takes something like 15l of water, and at a ratio of 50%/50%, 6 bottles is still under that ratio, but was told by the Silverton branch I've been to a few times, that should I need more it is easier to top up with another bottle than to try get rid of some antifreeze/coolant. DON"T BY THE CHEAP SHHHHHHH..... stuff i mean, there is, I have been told a certain amount of Hydrochloric acid and all sorts of shhhh... stuff I mean, that is supposed to clean the radiator and parts. Acid and steel...... not a good mix in my books. Silverton are the guru's when it comes to radiators, their antifreeze/coolant is the one they recommend and they cant't sell us rubbish, cause if it stuffs up the radiator its their warranty at stake.... just my

I have a bigger radiator in my Patrol.... I think it came from a diesel freight locomotive... ... just kidding, but I know it is a bigger radiator, and I don't have a water temp gauge to get an exact reading. My only reference to the water temp is on the dash instrument cluster. I know there is a big degree of error on these gauges, but mine since all the hiccups I've had with my Patrol, NEVER even reaches the half way mark!!! It sits a fraction below the half mark, doesn't matter if I'm climbing a long steep hill, with EGT's sitting between 580 & 600 degC for the length of the hill with aircon on. I have also recently found out that my viscous fan is seized solid, so the fan spins flat out all the time. I'm sure this help get the temp down too.... but this also drains power which in turn works the motor harder, which makes the temp rise..... hmmmm.... ( note to self:- I must replace my viscous!!!)

I also have an external oil cooler fitted, but again no accurate gauge to see what the temp is..... ( another note to self: get a Madman system).

I would consider a serious flushing of the system. The water ports that allow water up from the block into the head are small little holes, getting bigger towards the rear of the engine.... trust me I know every bolt on the TD 42 motor.... ... as I have re built my motor once and replaced the head twice ..... so over time maybe those holes have narrowed. Do you know how the radiator water was maintained prior to you owning the Patrol? I noticed on the 3month old head I had to replace how quick the "rust" build up around the water ports

Keep us posted !!!

[ricster]

I second what Peter Connan said.... speak to Frans ( Tour de Frans ).... I'm up here in JHB and he's in the Cape..... He assisted me many many times with info on what to do and how !!! The man is the King with regards to the overheating side of things and anything to do with the TD42.

[McNamara]

Thanks Ricster
"Old Red" is in this morning to Dacon Diesel for a 2 stage fuel pump. We also decided to move the EGT probe to just above the turbo and for good measure change the water pump. Silverton did the 3 core radiator and I will make a turn there to get their antifreeze. The cooling system I don't think was well maintained as the reserve bottle was brown with rust build-up. Deg C or F I will have to check.

Regards
Wayne Mac

[ricster]

2 stage fuel pump??... tell us more??... I'm a bit "doff" regarding this...

If your radiator water bottle was/is brown in colour from rust particles then there is a good chance that the water chambers inside the block and head are a bit yuk. Check with the silverton if they can recommend a product to give the internals a good clean !!! Maybe even do this a few times. If it is an aggressive product ( probably high hydrocloric acid content) then make sure that you flush the entire system ( with the heater set to max ) many times to get it all out!!

The td 42's we get here were almost all with aftermarket turbos, and don't enjoy the turbo being fitted..... BUT... look after it and pamper it with GOOD QUALITY OIL regularly and it WILL give you a lifetime of fun.

The head that I have fitted on now I got from Nissan Agents, apparently is for the TD42 motor they fit into the Patrol pick up, which comes out standard with a turbo & intercooler from Nissan. I assume there was a slight change to the way the water circulates in the head, but I can only take Nissans word for that. This too could have made a difference to my cooling temps.

Just a thought here..... if your egt's readings are wrong ( assuming they are ) could the oil and water temps also be out of whack??..... just a thought. when your water temp is high ( 115deg ) what is the gauge on the dash showing?...

[ricster]

You know what... I just re-read your first post.

You say the head had a crack in it?? I assume it was replaced? Was it replaced with a Nissan Agents head, or from a head repair/ remanufactured shop?? Before fitting the Nissan head, I bought a new non genuine Nissan agents head ( not reconditioned )from a certain motor spares company ( not going to mention names) and never pressure tested the head as it was brand new. Turned out that the plonker that did the machining did not drill the holes that take the water from the block to the water chamber in the head all the way through on 5 of the holes!!!! therefore water was not moving through quick enough, which caused that 3 month old head to badly crack at the no 2 and no 5 cylinder !!!

While at silverton let them do the test with the blue liquid to see if there is exhaust gasses in the system...... I don't want to be the bearer of bad news but there could be a crack in the head that opens up when you work the motor, probably around the no 5 cylinder between the precom chamber and the valve.

I tried to load a photo .... but it still won't let me. PM me your e-mail address and I'll send you a photo of the crack in my head..... no wait.... that just sounds wrong... I'll send a photo showing the rust on the water ports and where the crack developed between the precom chamber and the valve....