Anyone's fuel cooler have a thermostat and spring in the end?

[Designosaur]

Pulled the fuel cooler off to fix the leaks this afternoon. When I pulled it apart on the bench there is a thermostat or something in the cap at the end closest the firewall.

Does anyone know if this is available as a replacement part, the rubber washer on the end of the thermostat is a bit knackered and there is a star washer type of clip thing holding the spring in place which has fallen apart due to corrosion as well.

Does it need the thermostat in there at all? Later ones must not have it because no one mentions it in any of the tutorials on redoing the o-rings.

Can I just leave it out?

Thanks
Bernie

[Designosaur]

Well for better or worse I decided to leave it out. I guess no thermostat is better than a broken thermostat. I will see if they are available somewhere during the week.

All back together and not leaking so far. I will be keeping a close check on it.

It was really good to replace the o-rings as the cooler had been previously bodged with silicone sealant.

Bernie

[twr7cx]

Look it up - Landrover Parts Catalog (http://lrparts.net.ru/)

[bob10]

Does it need the thermostat in there at all? Later ones must not have it because no one mentions it in any of the tutorials on redoing the o-rings.

Can I just leave it out?

Thanks
Bernie

No. That thermostat is an integral part of the system, designed to supply an adequate supply of coolant to the fuel cooler, without it, I suggest the life of your fuel pump may be reduced. Next time you go on a long drive, place your hand on the fuel tank. Also, by removing that thermostat, you could possibly interrupt the designed coolant flow, with dire consequences. The TD5 coolant system is a different beast to all that went before it. You really must purchase a RAVE DVD , & get an understanding of the vehicle. Cheers, Bob :)

[davrac]

I rebuilt mine today and would suggest that removing anything that changes the spped of the coolant flow would be "not a good idea".

However if you want to cool your fuel further it would not be harmful to add an additional cooler. I services a 2009 diesel hilux recently and observed a very nice air/liquid fuel cooler mounted under the passenger side floor. Very tidy indeed. I am going to do some searching during the week to see if I can find one aftermarket.

Probably no different to fitting a B&M or PWR type cooler, just seemed a good idea for the Land Rover due to the temps he fuel reaches in the tank.

Food for thought.

Dave

[northiam]

Removing the fuel cooler thermostat could only increase coolant flow to the fuel cooler thus cooling the fuel more.

Feel the the temperature of the filter near the tank to confirm.
Mine runs hot to the touch.
Rave states the fuel temp runs over 82c
I reckon it will be fine for a while:o

[Designosaur]

Hi All, thanks for the input everyone. I will chase around a bit during the week and see if I can find a replacement thermostat, without having to get a whole new cooler. The input and advice is much appreciated, these are complex engines and I'm learning as I go on this one.

Any leads on a place to get a new thermostat would be great:)

[northiam]

See the attached
Land Rover Defender Discovery 2 Fuel Cooler PIB000080 | eBay (http://www.ebay.com.au/itm/280875077309)
The 04 td5 on had a redesigned plate type fuel cooler and no thermostat...
Regards

[Designosaur]

Thanks for that link Northiam, not that i'm going to run off and buy one if I can at all avoid it, but good to know that the thermostat was redesigned out!

I have tested the thermostat which was in there, it did expand a little in hot water but then jammed in that spot, I'm happier to have no thermostat than the possibility that it might jam in the closed position.:o

Cheers
B

[bob10]

See the attached
Land Rover Defender Discovery 2 Fuel Cooler PIB000080 | eBay (http://www.ebay.com.au/itm/280875077309)
The 04 td5 on had a redesigned plate type fuel cooler and no thermostat...
Regards

Plate type fuel cooler? How does that work, thanks, Bob



https://www.aulro.com/afvb/images/imported/2013/10/821.jpg

[bob10]

just a tip for any one removing/ replacing the fuel cooler. There is a technical Bulletin out regarding the top 2 mounting bolts.

" there is a risk of stripping the inlet manifold threads for the upper two fuel cooler mounting screws when tightening to the original specified torque.

Cause- insufficient screw thread engagement in the inlet manifold to support the tightening torque normally specified for an 8mm fixing.

Fix- tighten the top two screws to the revised torque of 18Nm. , & apply Loctite 242 .

The lower fixing screws torque remains at 25Nm, Loctite not required."

[OffTrack]

but good to know that the thermostat was redesigned out!


I'd point out the MY04 had fairly substantial changes made to the cooling system, so it isn't a matter of LR just deleting the thermostat. There was a revised cooler to radiator hose, and the radiator bottom hose was altered to include a return from the fuel cooler. This suggests that the entire coolant flow through the cooler was redesigned.

The MY04 bottom radiator hose is significantly different to the simple angled hose in the 99-03MY's:
https://www.aulro.com/afvb/



cheers
Paul

[bob10]

I'd point out the MY04 had fairly substantial changes made to the cooling system, so it isn't a matter of LR just deleting the thermostat. There was a revised cooler to radiator hose, and the radiator bottom hose was altered to include a return from the fuel cooler. This suggests that the entire coolant flow through the cooler was redesigned.

The MY04 bottom radiator hose is significantly different to the simple angled hose in the 99-03MY's:
https://www.aulro.com/afvb/



cheers
Paul

That is interesting, I have to go to MR Auto for some hoses this week, I'll see if they can put some light on the subject. RAVE states " A 'T' connection at the rear of the cooler provides a connection for the coolant return from the heater matrix & coolant return from the fuel cooler. The 'T' connection houses a thermostat which opens at approximately 82degrees c. This prevents the cooler opening in cold climates. " Considering our climate, does this mean you can remove the thermostat? Possibly best to leave it in, I don't know their definition of a cold climate. Bob

[mrjc]

Pulled the fuel cooler off to fix the leaks this afternoon. When I pulled it apart on the bench there is a thermostat or something in the cap at the end closest the firewall.

Does anyone know if this is available as a replacement part, the rubber washer on the end of the thermostat is a bit knackered and there is a star washer type of clip thing holding the spring in place which has fallen apart due to corrosion as well.

Does it need the thermostat in there at all? Later ones must not have it because no one mentions it in any of the tutorials on redoing the o-rings.

Can I just leave it out?

Thanks
Bernie
Hi Bernie,just out of interest when you replaced the o-rings did you use one or two on each end? i'm doing mine next weekend some say one some say two. thanks jamie..

[northiam]

Plate type fuel cooler? How does that work, thanks, Bob



https://www.aulro.com/afvb/images/imported/2013/10/821.jpg

See the attached link.
Brazed/welded construction for the D2 eliminated the O rings etc.

Plate heat exchanger - Wikipedia, the free encyclopedia

Regards

[Designosaur]

Hi Bernie,just out of interest when you replaced the o-rings did you use one or two on each end? i'm doing mine next weekend some say one some say two. thanks jamie..

Hi Jamie, I used one because that was what I ordered from the bearing shop, if I had read offtracks post about doing the job before I ordered them I would have gotten two for each end, they were only about 4 bucks each.

Having said that, the second spot where you can fit an o-ring is a little bit narrower than the correct position, so it is not designed to have the two there. I wouldn't think that it would hurt though, even just to prevent the assembly wriggling around as it ages.

They went in a lot easier than than they came out after cleaning up all the silicone and adding a little bit of rubber grease!

B

[rvt]

I'd point out the MY04 had fairly substantial changes made to the cooling system, so it isn't a matter of LR just deleting the thermostat. There was a revised cooler to radiator hose, and the radiator bottom hose was altered to include a return from the fuel cooler. This suggests that the entire coolant flow through the cooler was redesigned.

The MY04 bottom radiator hose is significantly different to the simple angled hose in the 99-03MY's:
http://landstore.pl/media/catalog/product/cache/1/image/800x800/5ba969ee066adb12576a5433872541c4/p/c/pch002080-3.jpg



cheers
Paul
Does anyone have a diagram of the MY04 coolant hoses layout please? I'm particularly interested in whether a restrictor is required for the newer fuel cooler.

I'm fitting the new type cooler to an MY00 D2. Will be using the newer hose layout. Not sure if the radiator has ever been replaced, will check what type it is when it's all apart.

[laney]

I have had no thermostat in my fuel cooler for about four years with no ill effects in fact I think the car runs better without it .

[pjh4159]

Removing the fuel cooler thermostat could only increase coolant flow to the fuel cooler thus cooling the fuel more.

Feel the the temperature of the filter near the tank to confirm.
Mine runs hot to the touch.
Rave states the fuel temp runs over 82c
I reckon it will be fine for a while:o

In Australia this thermostat could be removed as long as you don't live in very cold locations, I live in Queensland and have just removed my thermostat when replaceing the O rings. The thermostat blocks coolant flow for a period to warm up the diesel fuel which typically thickens in cold conditions, the fuel rail in the TD5 system always runs very hot so improving the flow and lowering the temps have to be a good thing in warmer climates.

[Tombie]

In Australia this thermostat could be removed as long as you don't live in very cold locations, I live in Queensland and have just removed my thermostat when replaceing the O rings. The thermostat blocks coolant flow for a period to warm up the diesel fuel which typically thickens in cold conditions, the fuel rail in the TD5 system always runs very hot so improving the flow and lowering the temps have to be a good thing in warmer climates.

Not true, and a similar stance has been the demise of many a vehicle with the Cooling system thermostat removed.

The thermostat has 2 functions.

Initially it helps warm the fuel, warm fuel = better flow through injectors.
Once up to temp, the thermostat slows the flow through the cooler, allowing the coolant more residence time to actually absorb the thermal load. Fast flowing coolant doesn't cool anywhere near as effectively.

There is a reason its called a "Cooler" and not a "Heater" [bigwhistle]

[onebob]

Not true, and a similar stance has been the demise of many a vehicle with the Cooling system thermostat removed.

The thermostat has 2 functions.

Initially it helps warm the fuel, warm fuel = better flow through injectors.
Once up to temp, the thermostat slows the flow through the cooler, allowing the coolant more residence time to actually absorb the thermal load. Fast flowing coolant doesn't cool anywhere near as effectively.

There is a reason its called a "Cooler" and not a "Heater" [bigwhistle]

[emoji736]…. and be sure that the “flow restrictor” is installed in the fuel cooler’s lower radiator coolant feed hose.

[johnp38]

I have removed my fuel cooler completely but vehicle not on road yet. (waiting on injector washers and o-rings)

Keeping everything to refit if it turns out fuel temp climbs, also considering an inline finned one out of the engine bay too .

Cut my return line to reroute now can't get the fitting on to the hard plastic line, and outlet thread on fpr needs retapping[bawl]

Many ways to skin the cat on youtube, but real life not the same as out of the vehicle on the bench everything going smoothly videos, with cockups edited out.

[PhilipA]

I put 2 orings in mine about 7 years ago and it hasn't leaked since.
Regards PhilipA

[laney]

Had no thermostat in my fuel cooler now for about 7 years with no ill effects car runs perfectly.:thumbsup:

[Nashvegas]

Reads entire thread with interest
Googles "what does a fuel cooler do diesel"

- v8 guys

[johnp38]

Re needing a fuel cooler

Has been on road sort of (well, it's a landrover) and no fuel cooler is no problem at this stage.

Did some reading up and diesel has a good operating temp around 45 Celsius , lower temp than that and the gain in power due to density not enough to justify the effort of cooling it further , higher temp is for reductions in Nitrogen Dioxide and slightly better atomization but losses in density/power.

Have done a few drives with Nano attached and it is running 10 to 15 degrees cooler than engine temp with no cooler hooked up (it's on carport floor somewhere)

With fuel cooler in it was at engine temp.

HOWEVER, in the original design of my car (1999 D2) the water flow was through the completely separate section at the bottom of the radiator which I have read somewhere ( have done a lot of reading on this since my last post in this thread but no notes other than in my head and no links sorry) runs a few degrees cooler than the top engine cooling section, so fuel cooler IS a cooler not heater as diesel has additives for cold weather (how is it sposed to stop cold weather gelling when your car is switched off overnight?)

BUT my radiator has been replaced with an aftermarket unit (no lower separate section) and both the two lower nipples are part of the tank (and both open to the tank not top blocked and lowest nipple only flowing as per LR revised radiator), and my diesel temp always followed my engine temp as per pre cooler removal nano readings.

So summer is going to be interesting and I will be nano recording and picking high temp days to go on drives .

I think it operates best as a lower temp cooler in its pre LR radiator mod iteration and in the later revised radiator with no separate lower section and the oil cooler bypass outlet/inlet blocked it operates as a higher (engine temp) cooler to assist with emission demands ( EU3 requirements? ) while still not letting the diesel temp over run..

So from this I believe that the original cooler setup fed from separate lower radiator section with feed from the oil cooler bypass is actually a good fuel cooling setup from factory, and any mods to this system should aim to keep fuel down to I think it was about 60 -65 celsius as a compromise power/emissions or lower again (closer to 45 C as possible) for power chasing.

However my aim is a reduction in plumbing so crossing arse hairs that I get reasonable fuel temps over summer without needing to put a cooler back in circuit.

My diesel temp information is from BP and SHELL papers that I perused in my online wanderings.