Ideas for improving the 2LTE (1 Viewer)

[GTSSportCoupe]

One thing I've pondered is that the intake piping between the air filter and turbo is not particularly generous and also runs right over the top of the hot engine. Strikes me as being sub-optimal. I thought perhaps in the case of an intercooled setup this may not be very relevant but it'd be interesting to know just how much pre-heating of the intake air is happening pre-turbo.

The air coming from the turbo is much hotter than the engine bay. So the pipe over the valve cover probably cools the air more than it heats it. Marginally of course....

 

[Peter P]

Yes I realise that the turbo will heat the air significantly, but I also understand that a snorkel can help lower EGTs by supplying cooler air from outside the engine bay. I haven't fitted mine yet so the proof is still to be seen, but assuming for a moment this is true, it suggests the temperature pre-turbo has a not insignificant effect on the temperature post-turbo, in spite of the heat from the compression of the turbo. Alternatively perhaps it could be a case of the snorkel simply being less restrictive than the factory intake thus feeding the engine (turbo) more air than stock and this extra air could account for the lower engine temps. Perhaps it could be a bit of both. Anyway, I will find out any snorkel effect myself shortly. FWIW I was actually referring to the section of the intake piping before the turbo no after. Ie. logic was, if cool air from a snorkel helps, having the intake piping running over the top of the engine probably does not help. It would be interesting to measure the temps right before the turbo and compare this to ambient under different loads then do the same post snorkel install. That would clear a lot up.

 

[gerg]

Before I did my snorkel on my 60 my air box was sucking hot engine bay air. Despite all the extra plumbing from the snorkel my egts dropped and the turbo spooled noticalbally sooner. I was shocked but welcomed the improvement.

 

[GTSSportCoupe]

Sorry, I miss-read your post, I thought you meant the pipe after the turbo. Yes of course, cooler air into the turbo is a good thing. I forgot that the Hilux has the pre-turbo pipe running over the valve cover as well. I was picturing the Prado engine which doesn't have that...

 

[Peter P]

Aah yes, that looks a better design!

Finally got around to finding the exhaust side EGR block-off and what I discovered was pretty ghetto! Looks like whoever deleted it just cut the pipe off, bent it inwards and did some quick welding to seal it off. The gasket was this weird thing made of four thin layers of what looks like copper. Everything pretty rough and probably not sealing, so hopefully I have found the source of the mystery lawnmower sound my engine makes. Will fashion a better plate and figure out some sort of gasket.

Viscous clutch fan removed and all old oil drained. I'm planning to use 40mls of a mix of 7000 & 10,000 cSt silicone oils and will see how that goes.

Acquired a Tridon 82oC high-flow thermostat and tested this and the one it was set to replace in a pot on the stove. The existing thermostat was also stamped 82oC and began opening at that temp and was fully open at 87oC. The Tridon didn't even want to know until 87oC and wasn't fully open until about 92! So I assume this is faulty and they're not all like that. The opening is definitely bigger which I assume will be advantageous.

 

[Nas90tdi]

That's a correct exhaust gasket with the multiple thin sheets. The pipe fix is definitely ghetto for sure though.
There are 2 Tridon tstats. An 82C (180F) and an 87C (190F) If you have the 87C tstat. I wouldn't be too surprised to see it not fully open for a couple of degrees over that.
I run the 87C tstat and it works great. It was the final piece of keeping my temps down actually. The high flow means it will turn a larger volume over faster. So, it actually doesn't stay open very long. I have a temp probe on the radiator side of it as well. Let's me watch how it's working.

 

[nightwind]

What a great how to thread! It inspired me to action. I already did the EGR block but was a little leery to take out the whole EGR system and clean out the intake system. It all came apart pretty easy, cleaned up nicely, and went back together without a hitch, almost. I'm just not sure where this one vacuum line should connect.

[/IMG]

It's amazing all the extra parts that are leftover

[/IMG]
Chad Wells

Sent from my iPhone using IH8MUDp

Do you have any pictures from how was it done / parts required

 

[AirheadNut]

Do you have any pictures from how was it done / parts required

I posted some photos when I disabled the EGR in my first Prado, they are in the first link in my signature. I didn’t completely remove the system, I just blocked off the exhaust pipe, took out the VSV’s and removed the butterfly plates.

 

[Peter P]

That's a correct exhaust gasket with the multiple thin sheets. The pipe fix is definitely ghetto for sure though.
There are 2 Tridon tstats. An 82C (180F) and an 87C (190F) If you have the 87C tstat. I wouldn't be too surprised to see it not fully open for a couple of degrees over that.
I run the 87C tstat and it works great. It was the final piece of keeping my temps down actually. The high flow means it will turn a larger volume over faster. So, it actually doesn't stay open very long. I have a temp probe on the radiator side of it as well. Let's me watch how it's working.

That good to know re high-flow. No, my Tridon is definitely the 82oC/180F version, starts opening at 87 and is fully open by 92. The existing 'stat in the truck is also marked 82oC and this one functions bang on. Anyway, I will test the Tridon in the truck and compare as I guess I can just consider it an 87oC thermostat. Good thing is I know it will be fully open by 92oC so maybe it'll be just fine regardless.

I'd be curious to know what the principal behind the 4 layered gasket it. I'll probably ditch it, make a steel block of plate and I was thinking I'd use some red gasket seal between it and the exhaust manifold. However some quick googling suggests this sort of product might only be ok up to about 600F. Not sure what would be the best way to seal this properly.

One other thing... can anyone confirm or deny that it is necessary to use some sort of lock-tite product on the screws and bolts that are used in the viscous fan and to mount it? Or is "gudensnug" sufficient!?

Apologies for the terrible photo...

 

[GTSSportCoupe]

That good to know re high-flow. No, my Tridon is definitely the 82oC/180F version, starts opening at 87 and is fully open by 92. The existing 'stat in the truck is also marked 82oC and this one functions bang on. Anyway, I will test the Tridon in the truck and compare as I guess I can just consider it an 87oC thermostat. Good thing is I know it will be fully open by 92oC so maybe it'll be just fine regardless.

I'd be curious to know what the principal behind the 4 layered gasket it. I'll probably ditch it, make a steel block of plate and I was thinking I'd use some red gasket seal between it and the exhaust manifold. However some quick googling suggests this sort of product might only be ok up to about 600F. Not sure what would be the best way to seal this properly.

One other thing... can anyone confirm or deny that it is necessary to use some sort of lock-tite product on the screws and bolts that are used in the viscous fan and to mount it? Or is "gudensnug" sufficient!?

Apologies for the terrible photo...

You'll get best fuel economy with the engine running around 88C apparently. This is why I went for the 88C over the 82C.

The EGR gasket is MLS (multi-layer-steel). Even if they look terrible, they often work great! Don't throw it out yet. That spot is too hot for any gasket maker. Just make a new plate if you don't like the look of the welded one, and torque it down nice and tight on the MLS gasket. If you really want, you could just buy a new OEM gasket as well.

I've messed a bunch with the factory viscous fan hubs. I've never used lock-tite. Just 'gudensnug', haha. Have not had any problems yet.

 

[Peter P]

Great, thanks GTS. That's interesting re fuel economy. Perhaps it was fate that I ended up with the faulty Tridon that opens at 87oC

I've just been testing my viscous fan as per the instructions on the 'Blue fan clutch mod' thread linked on your original post. Turns out my fan was set with the screws almost to the anti-clockwise extreme which didn't open the valves until 145-150F. There's a big difference between this and 95F as suggested in the other thread! Thinking I'll set mine to 100F and see how that goes.

 

[Nas90tdi]

Same here. I didn't use any type of thread lock on them. No issues.
My fan was set to come on really late as well when I did the fluid. Works so much better now. Couple that with the larger diameter fan blades and it move substantially more air now.

 

[Dprio34]

@Peter P , Use at least 3/16th" steel when blocking the exhaust manifold. If you use a piece of 3" stock, there is very little cutting to do, since the layered gasket is approximately 3” in length. 3 linear cuts with an angle grinder, and drill 2 holes, and you are done. Clean it up with the bench grinder if you like.

Ditch the layered Toyota gasket after you used it to trace your template. Black RTV will be fine to seal that plate to the manifold, just a small amount around the perimeter. I'd use anti-seize on those bolts just in case you want to take that plate off in the future and tap it for a EGT probe.

I used blue locktite on my fan bolts/stud bolts to the water pump, but I have been known to screw stuff up.
I'd go with what @Nas90tdi recommended.

 

[Peter P]

Well folks... in spite of my best efforts to prevent it happening, the cylinder head on my truck gave out

I know that the cooling system was far from adequate when I bought the vehicle and I can recall at least two times I have let it get much hotter than I should have so it's not 100% surprising that this has happened. Not to mention what might have happened before I got it. Anyway, I'm just about to commit to having my mechanic replace the head, gasket and bolts. I think an engine swap would be too expensive and at least this way I will know I have a clean slate. After working on the cooling system I have had it performing much better but it is still prone to climbing in temp faster that I would like so I am considering taking this opportunity to upgrade the radiator as well.

The radiator below is available locally however it is apparently only suitable for the auto version of the 2LTE Surf. Can anyone here shed any light on why this would be and whether there may be a way to get this to fit my manual?

ALLOY RADIATOR TOYOTA SURF HILUX 2.4 & 2.8D - Redline Performance

The help in this thread is much appreciated as always.

 

[GTSSportCoupe]

Well folks... in spite of my best efforts to prevent it happening, the cylinder head on my truck gave out

I know that the cooling system was far from adequate when I bought the vehicle and I can recall at least two times I have let it get much hotter than I should have so it's not 100% surprising that this has happened. Not to mention what might have happened before I got it. Anyway, I'm just about to commit to having my mechanic replace the head, gasket and bolts. I think an engine swap would be too expensive and at least this way I will know I have a clean slate. After working on the cooling system I have had it performing much better but it is still prone to climbing in temp faster that I would like so I am considering taking this opportunity to upgrade the radiator as well.

The radiator below is available locally however it is apparently only suitable for the auto version of the 2LTE Surf. Can anyone here shed any light on why this would be and whether there may be a way to get this to fit my manual?

ALLOY RADIATOR TOYOTA SURF HILUX 2.4 & 2.8D - Redline Performance

The help in this thread is much appreciated as always.

Sorry to hear, was it the original head on there?

The newer model OEM heads (both 2LTE and 3L) seem to be much tougher and longer lasting. HOpefully the repair is a good investment.

That rad looks decent. I've run both a 52mm and a 48mm core in my LJ78. The 52mm core actually made a much bigger difference than I thought.

The difference with the auto version of the radiators usually is that they include an auto transmission cooler in the bottom. Other than that I don't know if there are any other differences. They probably both would work for you as yours is manual, but maybe would be a good idea to check with the other surf owners.

 

[Peter P]

Yeah, a bit of a bummer... Right before it happened I was thinking of how well the vehicle was running!

No actually the engine was already on it's second head. It seems it lasted about as well as the first one (80,000kms ish). Anyway, cooling is now much improved and I can keep EGTs below 1000f post-turbo so I will make sure I don't overheat it in future and hope for the best with the new head. I have put up a post on the Aussie surf forum so will see if I can track down a bigger radiator.

I knew full well when buying this truck that it would be a challenge but I hadn't quite realised just how under-engineered certain aspects would be. It's a shame because this Surf is in great nick and I really do like everything else about it!

 

[Dprio34]

@Peter P If your current radiator is in good condition / isn't leaking, I wouldn't replace the old one as insurance against damaging a new head. I have a stock radiator and thermostat, and I only see a 4 degree Celsius Water Temp rise with a 275 degree Celsius EGT rise during drives up steep grades. Meaning on flat terrain I'm at 375-410 Celcius and 80 degree Celsius Water Temp. On steep prolonged climbs, water temp may only rise to 84 degrees Celsius max while EGT approaches 700. That is too hot for my comfort level, but I don't think a aftermarket radiator would do anything to address those high EGT temperatures that the right foot won't address. Just my thoughts. I would invest the money elsewhere if your radiator is in good shape.

 

[GTSSportCoupe]

Yeah, a bit of a bummer... Right before it happened I was thinking of how well the vehicle was running!

No actually the engine was already on it's second head. It seems it lasted about as well as the first one (80,000kms ish). Anyway, cooling is now much improved and I can keep EGTs below 1000f post-turbo so I will make sure I don't overheat it in future and hope for the best with the new head. I have put up a post on the Aussie surf forum so will see if I can track down a bigger radiator.

I knew full well when buying this truck that it would be a challenge but I hadn't quite realised just how under-engineered certain aspects would be. It's a shame because this Surf is in great nick and I really do like everything else about it!

The second head that was put on your engine may have been one of the original part numbers still, and so still had the original flaws. The later generations heads seem to be lasting 200,000kms+ here in Canada. I spoke with one of the import part company owners here. He was selling containers of heads when the 2LTE first came to Canada. He said none of his customers have come back a second time for another cylinder head (they still own and drive the vehicles and many have put more than 200,00kms on them).

Honestly, I've run my engine up to 120C a number of times every summer the last 6 years while towing. I've put nearly 100,000kms on my new head with no issues. I do use Evan's Waterless Coolant though, which is the reason I'm not as worried about how hot I get it. Under normal driving it never gets hot.

 

[Peter P]

@Peter P If your current radiator is in good condition / isn't leaking, I wouldn't replace the old one as insurance against damaging a new head. I have a stock radiator and thermostat, and I only see a 4 degree Celsius Water Temp rise with a 275 degree Celsius EGT rise during drives up steep grades. Meaning on flat terrain I'm at 375-410 Celcius and 80 degree Celsius Water Temp. On steep prolonged climbs, water temp may only rise to 84 degrees Celsius max while EGT approaches 700. That is too hot for my comfort level, but I don't think a aftermarket radiator would do anything to address those high EGT temperatures that the right foot won't address. Just my thoughts. I would invest the money elsewhere if your radiator is in good shape.

Hmm... are you talking about 700 celsius? Pre-turbo? That's pretty hot!? I can keep EGTs below 1000f if I ease back when the going get's really tough (this can get sloooow though!). The cooling system (which I know is very clean) even with a newish radiator, high flow thermostat, water wetter, new water pump can't really handle those temps for long though. I have a test run I do with some suitable hills and before I serviced the fan and cooling system the water temp would hit 100oC. Now it hits 94oC on the same run but there will be times it will get pushed harder than this and I suspect I'll still hit temps up near 100. I didn't get a chance to find out before the head went though! This is all without much of a load and in cool weather too... hence my comment about the cooling system being under-engineered. I have found the cabin heaters give about another 5oC of cooling but I feel embarrassed for the poor old thing when I have to resort to that haha.

I've also had a 2.5 inch exhaust fitted and this really opened up the engine up around 3000rpm. Can't say what this did for EGTs as I didn't have the gauge in beforehand.

Then I removed the throttle plates and this improved the response a bit at low revs. Also reduced EGTs 30-40F.

The last improvement was fitting a good snorkel. This seemed to help the engine breather better again but for some reason has had only a negligible effect on EGTs.

I plan to fit a boost gauge, controller and am interested to try the Pradocruzer bleed value idea to see if I can create a bit more headroom

Bit more of a journey than I had anticipated!

 

[Peter P]

The second head that was put on your engine may have been one of the original part numbers still, and so still had the original flaws. The later generations heads seem to be lasting 200,000kms+ here in Canada. I spoke with one of the import part company owners here. He was selling containers of heads when the 2LTE first came to Canada. He said none of his customers have come back a second time for another cylinder head (they still own and drive the vehicles and many have put more than 200,00kms on them).

Honestly, I've run my engine up to 120C a number of times every summer the last 6 years while towing. I've put nearly 100,000kms on my new head with no issues. I do use Evan's Waterless Coolant though, which is the reason I'm not as worried about how hot I get it. Under normal driving it never gets hot.

Actually I did wonder this as I think it was fairly early on that the head was replaced the first time. The head I'm looking at this time around is an aftermarket version that is $500 cheaper than the genuine Toyota. My mechanics says they've fitted a number of these and they've all performed fine. The manufacturer claims their heads all meet or exceed OEM quality and that they have improved some designs that have been problematic from factory but I don't know if this applies to their 2LT head. Probably I think, with all the changes I have made and with a new head, I'll be just fine going forward. I am going to fit a LED/buzzer to my Auberin water temp gauge. Should have done that at the outset as it's easy to forgot to look at them occasionally.