Outer Limits 4x4 Board

Ok so the sd33' and sd33t's run hot.. Does anyone know how to keep them under 95deg. ?? When towing with and SD they always sit around 95, regaurdless of weather.
I have a SD33T. Had a brand new rad. pressure reverse engine flush, serviced injectors, new water pump (old one leaking) Have put a new head on it, (got ripped off with 2nd hand motor) brand new genuine nissan bare head 1200$. Fan shroud that suits 2 inch body lift, and loacked up viscous hub, and a 10 blade fan not 6 or 7 or what ever they are.

After all this being a mechanic i still think it runs too hot. I want to buy and off road camper but cant see the point. Towing it with the old nissan will be sure to make it run hot considering is runs at 85deg. on a hot day. Ive towed 3.5tonne with the old girl in the early morn and arvo pulls like like a train, sits on 110kmh easy, just the heating..


Something in the cooling systems is very in-efficient. I thought maybe the hole in the back of the water pump cover, not letting enough coolant through. 2 things ive done that have made a huge improvement is more blades on fan, & advance the timming 5 to 8 degrees. Wholy shit go like a dog shot in the arse. No white smoke totally different engine tune. This has got the temp under control i hope.. Any thoughts let me know...

Sterlo

some times they biuld up shit in the oil cooler on the back rhs of block from memory not hard to strip n wash gunk of the cooler fins aslo a good idea to intercool sd33t to stop them cracking heads its a common fault
good luck
should only run 1/4 on std temp gauge

nastytroll is on the money! I am in the process of changing the oil cooler setup on my sd33t. I pulled mine off the block and it had corroded the casing and was all blocked - water couldn't circulate around the oil cooler. I had and 14â€

Hey sterlo, tell us more about advancing the timing, would be cool to get a few more ponies out of the old girl.

also, i put twin falcon thermos on one, and seemed to help heaps. also have a bonnet with 2 wrx scoops facing backwards to get some of that heat out of the engine bay, just need to fit the bonnet.


mine seem to slow down once the temp gets about half on the guage

CHeers

mine sits just on 1/2 way. pretty much independant of the weather. I thought that was a variable of the thermo valve spring that sits behind the waterpump.

at any rate yeah Sterlo, how do you go about changing the timing? a few more ponies sure as heck wouldent go astray.

Also a bit more info would be nice on how to go about intercooling the old girl. cheaply too if possible.


Vanne

if it always sits on 95 wouldnt that mean that the thermostat is regulating the temp at that and so if you wanted it cooler you could just get a cooler thermostat?

mine heats like a biatch atm.. just got a new old radiator... see what happens

Hey guys thanks for the responses.. Another thing i did find out during my troubles is that (thanks for reminding me Will) the dayco T-stat listed for the SD33 has a smaller hole in it than a genuine one and is set at 81 degress. The genuine T-stat is set at 76.5d and has a much larger valve hole.. Little thought there...

Pulled another SWB P40 home this arvo on heavy trailer but back wards with no back on it. wholy shit didnt get out of 4th or over 90kmh.. A lot of wind drag I think.. But it ran between 85 and 100de..

Nastytroll,, Ive often looked at the heat exchange and wondered,, Now u have mentioned it i might as well yank it off and have a look or bypass it altogether..


Inter-cooler hell yeah a top mounted 13B mazda rotory coolder.. I have seen picks of these they r VERY easy to fit. Im getting around too it, and tryin to source a ute cab to put on the SWB chassie!

You guys that are interested in the timming. I hold no responsibility for what you do but wholy shit u will notice the differance. Basically look under the P/S pump where the injector pump meets the timing cover and you should see a small line on the pump and on the timing cover. These are the factory base marks. All motors will run at this mark, wheather or not it is at its full potenial is up too you. I moved my pump about 8degrees anticlockwise.. So now from one line to another is about 3.5--->4mm. SD33'S are already very advanced for a 6, when the 2 lines are lined up that is 20 BTDC (before top dead center) Mine is greater that 25d. So far its a ripper even towing that huge trailer and car.. No white smoke at all, little bit of black under full throttle.

Too move pump simply loosen 4 retaining nuts @ front of pump (can get at these with a longish extension and universal joint) and 1 bolt under the rear of the pump, (support bracket) Move pump anticlockwise, tension everything back up again.. Start and head the totally different tune of the engine,, sound like a truck motor now..

Another thing i found hard on a motor that has 350 000 on it was that where the rocker arms pushed on the top of the valves the valve wore a massive resess in the arm. So when you set the clearance it was far from right depending on how worn they are. Me being in a hurry when I put the head back on wasnt going to fix them but a bit the bullet and pulled all the rockers, springs and shims off the pivot rod. Simple fix BENCH grinder,, dressed up all rockers arm so now spot on clearances .35mm and suprprize surprize 0 valve train noise,, I was quiet happy with them... People say why was time on such an old motor, get a TD42... I like my SD33T hope all you guys do too...

If anyone wants help let me know, let me know how you got with the timing pongo.. Its worth it for sure

Cheers Sterlo

Thats interesting, Very interesting. My friend is a mechanic for nissan was saying that my sd33 sounded like i needed to change the timing.


It also runs pretty hot, Round town and crusing through the bush slowley 1/4 temp On the highway 1/2 temp And Driving with a little bit of work up the bush It goes to 1/2- 3/4 temp. A little hot for my liking.

I've had an l28, p40, sd33 n sd33t the sd33t was the last before I went td42t. The sd33t went hard for what it was 186km/h according to the gps.
I would'nt advise bypassing the std oil cooler as they are very efficient just give it a clean, I,ve done a gu td42t std intercooler conversion on 1 n thet stoped all the EGT problems that kill the sd33t heads. My dad bought the sd33 new n it had 500,000km before it had blown the head gasket then another 250,000 with blown head gasket it always ran on 1/4 before then 1/2 after even towing 23 foot caravan when we stripped the engine it still looked new, still had hone marks in the bores.
My sd33t ute never got over 1/4, fit the intercooler n maybe an oil cooler aswell as std 1, also a good 2.5" exhaust n safari snorkel every 1 I know that has had a sd33/t has never had heating probs only EGT probs, n the dayco thermostats do make them run hotter

Hey guys, new to the forum here but after seein this thread had to join. I'm in the same boat as alot of people by the sounds of it.

My MK SD33 will sit on 1/4 maybe 1/3 around town and down the highway but as soon as you load it up going up a long hill it'll climb just over half, and one day goin down to rover park it was a really hot day climbin some monster of a range and it was right up to 3/4+ But that entire day it was sittin over half. Was loaded up and it must've been 37 degrees or something outside.

I'm pretty sure the radiator is in good condition and so is the coolant. The other day I brought a speco oil temp gauge, water temp gauge and a oil cooler. The plan was to hook the oil temp onto a T with the oil pressure switches and the water temp on the cold side of the rad to see the water temp going into the engine. Not sure where to hook the oil cooler up to though, is the line going to the VAC pump on the alternator OK or not enough flow. A guy from a 4WD shop suggested mounting it to the bonnet with a bonnet scoop. That way when you lift the bonnet to change the oil all the oil drains out of it. How would this affect oil pressure though?

Cheers
Michael

bung your oil temp sender in the sump. I reckon that would be the best spot. But ive never had anything to do with fitting an oil temp sender.. Datto as you have prob read Ive done everything spent lots on trying to keep it cool. It's gettin better but i'd want to keep it cooler.. I want to buy a off road camper but i cant see the point unless i can get the old nissan running cooler. Might buy a GU turbo i think!!

Mine sitts 1/4 most of the time even off road.. sand sits 1/2 depending. towing a small car on tralier will sit 1/3 with a/c on but u work the old donk hard all the time on the turbo it will get just over 1/2. 46d day a/c on and no towing sits 1/2 bit over if on a hill,, Too me its too high and spent 1200$ on a new genuine head so im very careful.

Yeah, i've seen people spending shitloads of money to no advancment. I've been warned that the SD33 heads are very sustepible to cracking if they overheat, and after some heavy low range work out at cruiser at night i looked down to see the temp on the hot line, or over abit. I shat myself just stopped, after that i fitted twin thermo fans to the front on a manual switch, if i went offroading, the fans went on but i never needed them after that. The only time it'll get hot is going up big long hills or loaded down on a hot day. Usin ac brings it up abit too.

I havn't pulled the standard oil cooler off yet to inspect it, is there anything i should look out for when doing it?

on a side note i've noted my rig looses shitloads of power when it gets hot too.

Nissan put out differant radiators for some strange unknown reason, asthetically they all "appear" the same......


BUT


If you count the number of actual rows you'll find a HUGE diffearnce !
( just count down the rows on the front of the radiator)


I have seen as few as 36 cored radiators ( usually fitted to L28s without aircon )

43 cored jobs, mostly fitted to L28s with air and SD33's

49 cored radiators SD33's with aircon and the nissan factory TOW PAK.


&


I have two 51 cored radiators ( No your not getting em either ), both of these radiators came from lwb utes, one was a SD33T and the other was a L28, both had aircon & auto trans coolers fitted ( external unit thats very factory looking ).


I've also heard of 39 cores, 46 cores, & a 33 core radiator .......

Not all MQ/MK radiators are made in a 3 row configeration either, there are the odd ones kicking around with only 2 !!!



Count ya cores for starters and lets see where the differances are

49 here on my one, though not sure about 2 or 3 rows.

Mine has 37 rows down including the top and bottom.

MQ 1982 Factory diesel (now 308) 240 volt

Hey V8patrol.. You raise a bloody good point about the No. of cores in the rad, well I got no idea i might count them.. I hope its a lot because the bloody thing is new 430$ worth. I said SD33T when i ordered it. I also have a 3 other SWB MQ-MK's here one with L28 had A/C, N/A SD33 no A/C and a P40 no A/C. I'll count them up and post it. Also if anyones after any spares let me know.

And was the SWB turbo diesel 5sp meant to have 4.3 diff ratios??? Giving around 2200RPM @ 100kmh. My SWB staarted out as a L28 4sp. now turbo diesel 5sp with wrong diffs i think, Im doing about 2400-2500Rpm at 100kmh.

Cheers Sterlo

Mmm note to self, count rad cores and rows tomorrow. Mines a SD33 with air....actually, bugger it, i'll go check now

Ok i've got a 3core and i think i counted 36 or 37 but that was from the inside and i may have missed a few. Either way sounds like i got jibbed.

49 cored radiators SD33's with aircon and the nissan factory TOW P

Jibbed to the max! Ok, what physical size are the radiators, I know i'm been a pain, but lets see if we can get a chart up with the vehicle its in, engine (standard) no. of cores and rows and physical dimensions (If you can be arsed)

I'll check mine properly tomorrow with dims and post up

ok, im no machcanic what part am i counting?

the little bars that the water runs along from side to side with the fins attached.

Ok my details

Car: 87 MK SWB
Eng: SD33 NA with Air (5speed man)
Cores: 3
Rows: 37
Dims: 645Wx440H

Oh yeh my 37 row 1982 diesel had aircon and it doesnt have a factory tow bar now.

How can you tell how many cores the radiator has?

Get a torch or light and shine it through the radiator and see how many flatish tubes there are behind each other going from tank to tank. I would assume most would be 3, but as V8Patrol said earlier, apparently theres some 2 core ones getting around.

juls wrote:How can you tell how many cores the radiator has?

You count them

The radiator has what are known as "cores"

These are small tubes that run across the face of the radiator and are seperated by a very thin brass webbing.
If you get a magnifying glass and have a close look you'll see small rectangular tubes running between the two tanks of the radiator, they are usually around 3mm high and 10mm across and run the width of the radiator

A bit like this..........
____________________________________________________
____________________________________________________
WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW
_____________________________________________________

As the air passes through the radiator water in the cores passes heat into the air passing between the cores and the brass webbing

There are usually 3 rows of cores in a single plane of cores & there may be up to 51 of these planes of cores.

The 3 row setup is called a 3core radiator, obviously if theres only 2 than its a 2 cored radiator.



Simply count the number of horizontal cores from the top of the radiator down to the bottom. The smaller numbered radiators will have a larger core size, it will be around the 3.5mm thick mark.
The larger numbered radiators will have thinner cores, somewhere in the 2mm vacinity

To fit extra cores in they make em smaller and fit em closer together, simple really .

Now to really confuse ppl .............
some cars have verticle cores and some have horizontal cores

Patrols have horizontal cores

Kingy

Obviously the more cores you have the greater the air to core surface area is & therefore the better the cooling capacity


Kingy

saw an explorer radiator today, only 2 cores but each core was twice the size of mine. The whole radiator looked bigger then mine

i just checked mine, seems i have 13 horizoltal bars across it, then i grabbed my fone to take a pic and i turned the light on(bloody fone has a betta light than my petzl tikka!! grrr) and saw what appeares to be a second radiator behind it with shitloads of these bars in it, one every cm rather than every 3 cm it seemed, if not moreso. is this a 2nd radiator or is my head jst makin fun of me again?


ya can see the smaller barred '2nd' rad just behind the bracket in the right side of the pic. (appologies for bad quality)

i think k1barh has had his head off his for so long it may never run again. now he's killed the clutch what are mates for

tilts wrote:i think k1barh has had his head off his for so long it may never run again. now he's killed the clutch what are mates for

wow you have that many cores?? am i the only one failing to see the heating problem in tilts post?? hehe

dattopimp wrote:saw an explorer radiator today, only 2 cores but each core was twice the size of mine. The whole radiator looked bigger then mine

trust me mate what ever your thinking DONT just stop thinking its not worth it...... ah... ah ... i said stop it... ok STOP!

anything from an exploder is a piece of sh*t, i work for ford. anything and everything that could possibly go wrong, snap, overheat, make a worrying noise, render a vehicle unsafe to contemplate driving out of your driveway, leak copeus amouts of anything onto the worst possible place or componet. Ford have designed and mannaged to fit into the explorer