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2003 GUIII - TD27T
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Interested in how you tested this.
We've found the opposite through testing (with a modified pump) that the vacuum created from an undersized bypass is relieved when the thermostat opens.

In regards to thermostat operation, the one thing I don't want is the thermostat to be a FULL open. As you state the thermostat has lost control and only reducing load will reduce temps
what's the questions about pressure about?
when the bypass is fully open /thermostat fully closed,
this is not a normal operating area.
as soon as the temp gauge starts to move that's is indicative
that the thermostat has done it's 1st task,
remained closed so the engine can heat up faster,
it's now onto the 2nd part of it's job.
i don't think a cold engine gives a hoot about high vacuum on the suction side or high pressure on the output side.
and these conditions are null and void once the thermostat starts to operate.

You are doing thorough testing, but to what benefit?

I mean, when the thermostat is just opening
is never going to be a situation under normal operating conditions
where the potential/likeihood of the cooling system not being able to cope is going to happen.

I'd be more interested in what's going on when the thermostat is fully open and bypass fully closed.
because that's when temps run away uncontrollably.


and how is that the opposite? or even relevant,
TD's aren't in any danger of overheating when the thermostat is just opening.

I find it interesting when you keep saying "undersized" bypass.
when earlier in this thread "GQShayne" and I were discussing coolant flow
and the role the bypass plays
and that the bypass could possibly flow a lot more than it's gets credit for,
you suggested he has a rethink, what's changed between now and then?
 

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nissan patrol
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i don't think a cold engine gives a hoot about high vacuum on the suction side or high pressure on the output side.
and these conditions are null and void once the thermostat starts to operate.

These two measurements of the cooling system would have to be some of the most important in relation to cooling system stability.

Firstly you talk of a cold engine, if your cooling system has issues when cold, they aren't magically going to disappear when the water heats.
If you water pump is creating a vacuum, it's telling you a couple of things.
Firstly the flow into the pump is insufficient.
This will relate to not maximising flow out of the pump. Cavitation can also be created. But not always. Having a variable speed engine can also show the pump to behave at low speeds but turn to a milkshake output at rpm above 2000. Again why it is vitally important to have visual on water quality entering and leaving the pump. Alleviate the guess work.
Secondly creating a vacuum in a cooling system would have to the last thing you need.
If your pump makes 15psi pressure but also makes 2 inches of vacuum on the inlet then they ate basically cancelling each other out.
The vacuum will also lower the boiling pressure in the system and exactly where the vacuum is greatest......
IN THE EYE OF THE PUMP.
 

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2003 GUIII - TD27T
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These two measurements of the cooling system would have to be some of the most important in relation to cooling system stability.
I don't think a cold engine gives a hoot about high vacuum on the suction side or high pressure on the output side.

Do you not understand english or have a problem comprehending sentences?
or did you miss the last sentence?

"and these conditions are null and void once the thermostat starts to operate"

i'll put this here again, cause i think you missed this too.....

I'd be more interested in what's going on when the thermostat is fully open and bypass fully closed.
because that's when temps run away uncontrollably.
 

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nissan patrol
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I don't think a cold engine gives a hoot about high vacuum on the suction side or high pressure on the output side.

Do you not understand english or have a problem comprehending sentences?
or did you miss the last sentence?

"and these conditions are null and void once the thermostat starts to operate"

i'll put this here again, cause i think you missed this too.....

I'd be more interested in what's going on when the thermostat is fully open and bypass fully closed.
because that's when temps run away uncontrollably.

I'm trying to explain so I don't offend.

But what don't you understand??

If it don't work when the coolant is cold, what makes you think it will suddenly be OK when the coolant reaches 90°c??

And your testing???

No existant.
 

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GQ Dual Cab. TD42Ti with fruit.
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For most engines the bypass is not a variable, thermostat dimensions excepted. It is close to being a constant for all of us.

But I think that each individual size radiator that is used is a variable that will effect pump effectiveness. Also, each brand water pump may be different, with tolerances between 3mm and 6mm noted in the past. Then you add in any of the modified versions that are being used, and there are plenty of those. Just between the three of us, we have three different water pumps.

So you fellas have noted different results, but I would expect that to be the case.
 

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2003 GUIII - TD27T
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I'm trying to explain so I don't offend.

But what don't you understand??

If it don't work when the coolant is cold, what makes you think it will suddenly be OK when the coolant reaches 90°c??

And your testing???

No existant.
It's hilarous that you think you're trying to explain something
when you don't even understand or fully comprehend what is going on.

I've stated a few times my conclusions on my findings and even asked a few times for you to share your tests results, but you don't want to do that do you?

Here i'll put up the question again......

What happens when the thermostat fully opens and the bypass fully shuts.

Testing for a closed thermostat is a complete waste of time, all your're doing is simulating a cold engine with a seized shut thermostat. hardly normal operating conditions.
 

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nissan patrol
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What happens when the thermostat fully opens and the bypass fully shuts.

You have lost control of cooling system.
What's happening is the system is trying to push all of the water to the radiator for cooling.
This is when the band-aid fixes come out. Bigger radiator, more aggressive fan and hub.

The question is why has the cooling lost control.

The pump plays a major part here.
It needs to have good flow, make pressure and NOT cavitate.

I have only seen one pump meet these criteria.
 

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nissan patrol
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Screenshot_20201227-104758_Gallery.jpg

Testing for a closed thermostat is a complete waste of time, all your're doing is simulating a cold engine with a seized shut thermostat. hardly normal operating conditions.
Unfortunately No.
The thermostat should cycle dependant on load. Low load circumstances will see the thermostat close and very marginal open then close.... only if you have a stable cooling system.

If not, then It will open, stay open and only close after the engine is turned off.

With the thermostat shut, the water has more time to cool.
As seen in the photo. Top temp is top hose.
Bottom temp bottom hose.
 

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It's hilarous that you think you're trying to explain something
when you don't even understand or fully comprehend what is going on.
Screenshot_20201227-120339_Weather.jpg
20201227_120353.jpg


Just out to pick up some lunch and these are the current conditions.
Over 40°c differential between top and bottom hose on a 27°c day at highway speeds.


Not bad for a bloke who has NO IDEA.
Could you image what we could achieve if we had half an idea??

Ohhh, if you couldn't work it out??

I run a hotter thermostat than the standard Nissan 77.5°c.
 

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nissan patrol
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20201227_120353.jpg


A picture tells a thousand words.

This is what I mean by light load.
Unladen car travelling at 100kph on freeway.
Bottom hose temp is at 44.6°c which the engine fan would be disengaged.
Top hose temp at 87.5°c, (actually still a little cold), but 10°c over standard.
The combustion process is starting to optimize, smoke is almost non-existent, optimizing fuel economy.
 

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2003 GUIII - TD27T
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You have lost control of cooling system.
What's happening is the system is trying to push all of the water to the radiator for cooling.
This is when the band-aid fixes come out. Bigger radiator, more aggressive fan and hub.

The question is why has the cooling lost control.

The pump plays a major part here.
It needs to have good flow, make pressure and NOT cavitate.

I have only seen one pump meet these criteria.
Yeah, tell me something i don't know.
you're claiming to have access to sight glasses
and pressure sensors placed all though the cooling system.
and could easily confirm or deny my earler statements on what is happening in this scenario,
yet you appear to avoid this.

As for you having no idea, yeah, i stand by that statement,

You tried to postulate that because the pressure in the cooling system was reducing
when the thermostat opened by as little as 1mm
that this was proof that the radiator was a path of lesser resistance than the bypass.

All it proved was that the combined (2 paths) was of lower resistance than just the bypass alone.
like i've asked earlier what's actually going on when the bypass ends up fully shut.
does the pressure drop off? does the pump suction skyrocket? have you witnessed a lot of aeration?

Why do you think i was asking for whatever testing you have on thermostat fully open/bypass closed scenario.
pressure measurements, visual accounts and so forth,

I know that when the happens my cooling system used to run away uncontrollably,
leading me to believe that the pump suffers greatly
when it has to suck all the coolant the long way through just the radiator,
leading to heavy aeration, hence the runaway situation.
i'm not going to say cavitation because i've seen no damage at all usually associated as such.
although there have been pics of cavitation damage posted, so it can happen.

The bypass fully closed situation is a last ditch attempt
to bring the cooling system back under control, yet it fails.
and fails miserably.
why does it fail?
it should by all rights sending the full volume of the pump through the radiator
bring the cooling system back under control very quickly. but it doesn't.

nice work on the outlet and inlet hose,
i was expecting about that sort of a difference,
i haven't got around to whacking another sensor on mine yet.

how much flow is going though the bypass and radiator at this 87 deg outlet temp?
50% through each path?
 

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SUI GENERIS UTE
GQ Ute 1990 Silvertop
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View attachment 527051



The thermostat should cycle dependant on load. Low load circumstances will see the thermostat close and very marginal open then close.... only if you have a stable cooling system.
That statement is a key criteria for a cooling system that works as intended.

My opinion and my understanding of what are solutions from a logical approach to our TD stability issue.

Firstly To achieve that you need a pump with enough volume and its associated pressure to overcome the block, head and radiator's resistance without the pump cavitating or producing aeration issues in the eye of the pump. Then you need a pump thats capable of flowing volume with velocity to be able to remove the engines loaded tune level heat production from the head to stop boiling bubbles forming on the precomb water gallery surfaces and possible the exhaust jackets. Then you need to balance the resistance of the system with bypass water to keep the pump within its effective volume flow criteria for the engines varying loads of heat demand. All the while having a thermostat heat controlling valve bypass enough volume of water through a radiator to cool sufficiently enough so the cooled returning coolant mixes with the high flowing internal bypass water to keep the system at a stable temperature.

Obviously there are a couple of ways to achieve a stable high volume bypass cooling system.

One being a fixed open ended bypass system so the pump is always near its full potential of flowing coolant volume This requires a high capacity water pump with volume ability to spare at all rpm points, so when the thermostat opens the pump has more than enough capacity to overcome the extra resistance and volume demand, but still maintaining that high volume velocity through the block/head. The tricky bit here is to have a thermostat valve (No bypass flap) that opens at the right point and amount to allow enough water to bypass to the radiator but not too much water so we get a good temps differential or cooling in the radiator or a big enough or oversized radiator with enough air flow to give more volume at the biggest differential of cooled coolant. Its all a balance of course but the idea is to have more than enough water flow in the block/head with a radiator capacity flow and cooling ability so the thermostat can cycles all the time at all load conditions. For example at light engine loads the thermostat will cycle slowly and for high loads we want a high cycle rates very quickly. You do not want the thermostat to reach a full open position at high loads thats when the system becomes unstable or over powered. This condition happens when you have way to much flow through the radiator or not enough air flow to get a good temp differential for the volume flow amount. So when the cooled coolant mixes at the internal bypass and into the pump lowering the input temps into the block/head is enough to be stable or to stop a run away over temp condition. Once the thermostat reaches full open the system is now unstable and zero control, Which also puts the thermostat in a condition where it cannot react to any temp changes up or down quick enough. Added to this in this full open condition the radiator is over powered and cannot cool the volume of water flowing through it with any effective differential. For stability i would logically suggest you need at least 15 degrees C differential in the radiator to start to be effective.

And secondly a good enough pump capacity matched to the heat load demand of the engine so as water flow volume in the system stays adequate for each rpm point and load condition by balancing internal bypass volume flow to radiator volume flow.. This is achieved by using a thermostat that controls radiator flow balanced against internal bypass flow like our standard bypass flapped thermostat is suppose to do. The very tricky part about this is to have enough volume and velocity in the block head without having too much or too little volume flowing through the radiator and or the internal bypass. Remember their is no such thing as too much velocity or volume through the block head but the bypass systems both radiator and internal bypass there can be too little and too much flow so a balance has to be achieved. This is harder to do compared to a open ended bypass with a huge capacity pump.

Herein lies the problem of the STD TD42 kettle issue. Our pump due to many design issues and set up issues and probable a gambit of other issues i could mention but wont go into here, is just not up to the task of keeping a performance tune level TD42 temp stable in all load heat conditions. First we need a better pump and or lower the flow resistances between block and head so the pump can work in its sweet spot for suction ability to output head pressure. But that will not fix the stability or temp run away issues. So then we need to control the bypass volumes internal system to keep flow volumes adequate in the block/head so more water flowing for a more stable or lower temp between head and block. Then to control radiator bypass to keep a nice temp differential to mix with the high flowing coolant in the block/head to keep temp stable. We also need enough flow volume velocity in the block/head so the reaction time to heat load is quick and reactive so the thermostat can react fast enough to push enough volume of water into the radiator to dissipate enough cooled water back into the system but not too much back into the radiator to lower the radiator temp differential too much or over power the radiator with heated water flow..

Its very difficult to test flow volumes in our system, i have tried and got nowhere except melted flow meters. But a good guide is temp probes in the block and head in different positions and inlet and outlet of the radiator. Also for a good complemented measure is pressure between block and head and at the radiator. Also a good guide is pressure in the internal bypass if you have a external bypass. Ideally i believe we need enough pressure or a pressure where there is little differential between block and head and external bypass if you have one. And BTW there are different ways to plumb in external bypasses to varying degrees of success depending on what pressure you can stabilise at the different rpm points.. From my testing i did find at about 10 psi @ 2400 rpm cruse speed loading and above without system pressure added, the pressure differential did become acceptable head and block as did temperatures head and block and through the head. My logic then suggests we have enough volume flow to be at a equilibrium to maintain temp stability in the block and head. Firstly i have to say i did modify the holes in the block head transition, to maintain a lower differential pressure between the head and block so less resistance so to speak for more water flow through the head logically. As i said above, i failed at measuring flow volumes so this is guess work with logic. The secondary benefit with this criteria is i managed to see a lot less aeration from the pump when pressure and temp differentials were lower in the block and head. Only logic here as its impossible to look in the head and pump inlet while running or for that matter at any time. But my theory with logic suggests we have enough volume flow velocity to keep bubbles from forming on the precomb's and possibly exhaust jacket galleries, no proof here of course. But with a modified std pump ( a sort of closed top impeller) operating at 2400 rpm @ 10 psi loaded on a fixed speed load dyno we have zero aeriation and or cavitation if you must that i could detect using clear tubes or in a clear tube external bypass. The STD pump with 3+mm impellor clearance will not reach 10 psi, system pressure compensated at any rpm ever, actually its busting its ass to make any pressure when the thermostat cracks open even at idle it hardly makes 0.1 psi thermostat closed and cold..

Also to remember here all this testing and logic is for a true 200 rwkw @3700 rpm 780Nm @ 2050 rpm TD engine so my heat load is very much higher than the average TD42 engine hence the varying degrees of adjustment for each tune level engine.

I apologise again for my wall of text.
 

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SUI GENERIS UTE
GQ Ute 1990 Silvertop
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Yeah, tell me something i don't know.
you're claiming to have access to sight glasses
and pressure sensors placed all though the cooling system.
and could easily confirm or deny my earler statements on what is happening in this scenario,
yet you appear to avoid this.

As for you having no idea, yeah, i stand by that statement,

You tried to postulate that because the pressure in the cooling system was reducing
when the thermostat opened by as little as 1mm
that this was proof that the radiator was a path of lesser resistance than the bypass.

All it proved was that the combined (2 paths) was of lower resistance than just the bypass alone.
like i've asked earlier what's actually going on when the bypass ends up fully shut.
does the pressure drop off? does the pump suction skyrocket? have you witnessed a lot of aeration?

Why do you think i was asking for whatever testing you have on thermostat fully open/bypass closed scenario.
pressure measurements, visual accounts and so forth,

I know that when the happens my cooling system used to run away uncontrollably,
leading me to believe that the pump suffers greatly
when it has to suck all the coolant the long way through just the radiator,
leading to heavy aeration, hence the runaway situation.
i'm not going to say cavitation because i've seen no damage at all usually associated as such.
although there have been pics of cavitation damage posted, so it can happen.

The bypass fully closed situation is a last ditch attempt
to bring the cooling system back under control, yet it fails.
and fails miserably.
why does it fail?
it should by all rights sending the full volume of the pump through the radiator
bring the cooling system back under control very quickly. but it doesn't.

nice work on the outlet and inlet hose,
i was expecting about that sort of a difference,
i haven't got around to whacking another sensor on mine yet.

how much flow is going though the bypass and radiator at this 87 deg outlet temp?
50% through each path?
Bathy i haven't decided if you are posturing with Plumma or genuinely searching for answers. I write here with the presumption you are after some answers or different views on our TD cooling issues.

To start with i have fitted sight tubes be it acrylic which change colour very quickly with heat. I have fitted temps probes in the block where i could and a couple of extra drilled holes at 1/8 BSP in the block to check heat distribution. I fitted probes in the head as well using the 5 x 3/8 BSP plugs in the head under the rocker shaft using short 90 degree probes also 2 probes solded into the 2 welch plugs at the back of the head.

With the std pump i didn't observe radical temp differences through the head like some others suggest. I didn't observe cooler temps at the first bung at the edge of the cylinder between 5 and 6 exhaust side and the last bung near the edge and on top of number 1 cylinder. But i did observe the block temp was near the same as the temps at the back of the head in the core plugs. There is a pretty big temperature differential between block and head though with std pump, even when i closed up the impeller gap to under 1mm or so. This observation set me in a different direction from what others did. I changed some temp probes to tube and pressure gauges as i couldn't fit pressure sensors under the rocker shaft. This data told me a lot more than temps could alone. I found there is a substantial pressure drop across the head and a substantial differential from block to head. This suggested a difference in flow rates in the head with the tiny temp differences to suggest this theory. The main cruncher to this was a suggestion by my very smart engineer, was to put temp and pressure probes in the side of the head at the welch plugs between exhaust ports and intake ports. Contrary to some perceived logic the temps on the intake side were considerably higher than the centre head temps and higher again than the exhaust side temps. This can be explained by where the probe are positioned in relationship to the precomb chamber. The precomb chambers are in the biggest galleries on the intake side.

With other very smart engineers advice i removed the head and adjusted all gallery transfer holes head and block to the gasket. The 2 little holes between cylinders in the head i adjusted these to near match the gasket head side and drilled out the block angled holes to 5.5 mm leaving the front holes alone. On the block i used a magnetic base drill to drill the 4 back holes to 6mm straight down not at the angle. so the 4 back holes have an 5.5mm angled hole and a 6mm hole straight down. This mod is obviously not for everyone.

But the results with a std pump 1mm impeller gap was substantial and moving in a positive direction. I now had near equal pressure head and block at 2400 rpm. And temps were near equal side to side but a little cooler on the bungs under the rocker shaft. Assumption we have higher flow in the head. With my 200 rwkw engine it didn't solve temp run aways but it did prolong that condition and recovery was a lot faster.

At this point is when i started on the thermostat condition so i have no idea on what really happens pre head gallery mods. But i can confirm when the thermostat cracks you do see near zero pressure in the system at idle. That condition happens at 2400 rpm as well when cold. Under load the temps keep rising steadily and combined system pressure rises to about half thermostat travel (doesn't matter what temp crack thermo you use same result). At this point you can reduce the load and temps will recover quickly but continuing loaded temps rise a lot more quickly as pressure drops to near zero and more water travels into the radiator and the flap closes off the bypass hole. Then as the thermo hits full open all things get very messy head temps and pressure dont read logically some points pressure is readable and other positions near zero, and the pressure can bounce at times (i assume from aeriation) temps get erratic through out the system block and head as more and more bubbles are seen in the clear tubes. My theory is as temps rise as the thermostat opens more the pump just cannot supply enough volume flow to control boiling bubbles in the head and or the pump cannot get enough water into the suction side to work in its sweet spot so cavitation and aeriation happens causing instability in flow volumes as more volume is pushed through the radiator. To prove this theory A very simple bypass hose fitted from bottom radiator hose to thermostat housing under thermostat no other mods prolongs the overheat run away temps and aerations considerably. But doesn't fix my 200 rwkw engines overheat condition. Pump and thermostat mods are required to address that issue. As said i really haven't done any real long term testing on a STD power engine to suggest a fix.

Sorry again for my wall of text..
 

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nissan patrol y61 td4.2tdi
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Hi Team,
as I have said previously I am no expert on cooling systems either but I know what I have seen work in the past albeit on non-Nissan engines so I stand to be corrected.

I have previously mentioned on certain models of their engines Caterpillar use an orifice above the thermostat to limit coolant flow thru the radiator to help stop overheating--keeps the water in the radiator longer to cool more effectively for a greater temperature differential between the inlet and outlet--they call for an ideal temp differential of around 8 to 10 degrees F.

After reading of OM's and others experiences with our TD42 engines I wonder if the water flow thru the radiator when the thermostat opens and causes imbalance in the system due to possibly too large a thermostat opening could be controlled with a similar yet to be determined orifice above the t/stat.

Another approach may be to limit the thermostat opening/closing of the bypass that a limited opening/closing thermostat be used to the same end.
It seems the system becomes unstable when the thermostat opens beyond a given amount and so passes a possible sweet spot.

I have experience of when thermostats are removed to cure overheating engines for example with side valve Ford V8's they then overheat worse due to excessive water flow thru the radiator--the fix of the day was to fit a welsh plug in each bank upper radiator hose with a 5/8" orifice in it to limit water flow thru the radiator.

All the above waffle is an attempt to think outside the box somewhat and try to suggest another way to stablise the TD42 cooling system by limiting the outlet flow to the radiator with a fixed orifice---due to the common thought that when the T/stat opens beyond a certain amount the system becomes unstable--also to not completely shut off the bypass.

This is all worth what you paid for it and is my 2 cents worth.

Best Regards,
Eddie B.
 

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2003 GUIII - TD27T
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157 Posts
Bathy i haven't decided if you are posturing with Plumma or genuinely searching for answers. I write here with the presumption you are after some answers or different views on our TD cooling issues.

..........

Sorry again for my wall of text..
Genuinely after answers and don't be sorry for your walls of text. It has been most helpful.
your research/development has answered many of the questtions i was looking for answers for.
It is clear to me now (as i had "guessed" hahaha) that the water pump,
when faced with block/head restrictions as illustrated in your wall of text,
when coupled with the longer path through the radiator when the termostat loses control and fully shuts the bypass
can not cope and efficiency goes down the gurgler, and there is no recovery, it's all bad, unless you lift off the loud pedal.

Just shows how that at standard HP levels the cooling system is just barely adequate,
start pulling more power/putting more heat into it, it can't cope.

like i stated pages ago, i got real lucky with my TD27T,
a new waterpump, which coincidentally, i was in too much of a hurry to check impeller clearance
and big 3 core alloy radiator has managed to stop my bypass from closing,
under normal operation and towing even up to 3T, stable at 93 deg C.
but i do fear that if that bypass ever does reach it's closed seat, it'll still runaway uncontrollably.

If i ever have to pull the pump, i'll definately be checking impeller clearance,
may even mod it to a closed ring design like GQshayne posted up pages ago
and if i have to lift the head, then i'll be looking at opening up those passages too.

Cheers, Bathy.
 

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nissan
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Hmmmmm.
this is one interesting discussion one must say.
It has gone stale so I will rock the boat. hopefully.
It has morphed from we have too much bypass to too little, and every other ill fated conclusion someone can think of in between that.

So where are we all at??

Personally I have a blocked bypass in the thermostat housing and have massive issue that it on occasions reaches 196degF.
 

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nissan patrol
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Hmmmmm.
this is one interesting discussion one must say.
It has gone stale so I will rock the boat. hopefully.
It has morphed from we have too much bypass to too little, and every other ill fated conclusion someone can think of in between that.

So where are we all at??

Personally I have a blocked bypass in the thermostat housing and have massive issue that it on occasions reaches 196degF.

So, you have no bypass or do you have the 'Derk' bypass?

Which thermostat are you running?
 

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601 Posts
I can only speak for myself I think it's combination of things timing, fueling etc, I just come back from towing 2t brick away ( 33,4.1s, ufi 12,efr, new adrad, shimmed thermo mod allowing 4mm bypass ) and I'm hard pressed getting it to 600 in the dump,sitting 125 5th gear , AC on
guage didn't move.
But when I did the cam timing change when I rebuilt, I didn't move the pump so it was woeful and getting high egts and got the guage moving, since retarding timing and abit of tinkering it's finally close to where I want
jono
 

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nissan patrol
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I can only speak for myself I think it's combination of things timing, fueling etc, I just come back from towing 2t brick away ( 33,4.1s, ufi 12,efr, new adrad, shimmed thermo mod allowing 4mm bypass ) and I'm hard pressed getting it to 600 in the dump,sitting 125 5th gear , AC on
guage didn't move.
But when I did the cam timing change when I rebuilt, I didn't move the pump so it was woeful and getting high egts and got the guage moving, since retarding timing and abit of tinkering it's finally close to where I want
jono

When you say ' guage didn't move' that leaves alot of temp differential.

On my GU Ute, the guage moves to operating temp at 69°c and doesn't move a millimeter until about 100°c

If I was going by the factory guage then there was never a problem.
 

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With ill timing/tuning or stock pump/ turbo it did fluctuate ,
And at roughly 180 kw, I guess if it does start to move over say over 3/4 , ill need to look for a better solution
 
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