A Solution to the Hot Running D2 Engines

rovercanus

Well-known member
Apr 24, 2004
9,643
244
65-70MPH on a D2 is where the grill opening/radiator surface area reaches the tipping point of where it's no longer effective at keeping the temps stable. Not saying she's gonna blow by any means, but temps will start to creep past those speeds especially on a modified and lifted D2. I can cruise 55-60MPH and never break 193F with the HVAC on full blast, but speed up to 65-75MPH and the temps will go up to 206F range and sometimes 210F depending on the load on the engine (mountains/hills or hauling heavy cargo).

Inline mod makes it act more like a D1 and it certainly can idle for longer periods of time before the temps start to rise.
Say what now?
 
  • Like
Reactions: jymmiejamz

donniefitz2

Well-known member
Sep 15, 2020
138
56
Scottsdale, AZ
fitzventure.com
I decided to bite the bullet, bought and installed the inline kit. It's a nice kit and has very detailed instructions.

Previously, I had the gray 180 factory stat installed and it worked pretty damn well. But, it's been 115-118 degrees here over the past week and I was seeing temps creep up into the 210's (75mph) with the AC on going up hills. Getting tired of staring at that Ultraguage with anxiety.

My normal temps are 188.8 cruising without the AC on in weather below 90 degrees all day long. It idles at 194-197 without the AC on in sub 90 degrees.

The past few weeks (105+ degree ambient), I've been cruising at 50-55 mph at around 199-201 AC on and idling at about 204-206. Highway can get up to 210 and the highest I've seen is 215 going uphill (long steep grade).

So far, with the new inline setup, I can tell that the temps ramp up and cool down faster. Cruising 55 with the AC on is about 199-201 and highway was around 204-206 (75mph). Idle seems slightly better at about 199-201. All of these are with the AC blowing full blast and only 101 degree ambient. Big cooling trend in our weather today. Had to put on my parka.

It doesn't seem like a drastic difference so far over the gray stat, but it does react faster and is slightly (2 degreesish) cooler.

If anything, it does make changing a thermostat way easier.

I'll report back after I hit some 110+ degree temps on the highway if there's any appreciable difference.
 

Swedjen2

Well-known member
Sep 12, 2018
594
127
California
I decided to bite the bullet, bought and installed the inline kit. It's a nice kit and has very detailed instructions.

Previously, I had the gray 180 factory stat installed and it worked pretty damn well. But, it's been 115-118 degrees here over the past week and I was seeing temps creep up into the 210's (75mph) with the AC on going up hills. Getting tired of staring at that Ultraguage with anxiety.

My normal temps are 188.8 cruising without the AC on in weather below 90 degrees all day long. It idles at 194-197 without the AC on in sub 90 degrees.

The past few weeks (105+ degree ambient), I've been cruising at 50-55 mph at around 199-201 AC on and idling at about 204-206. Highway can get up to 210 and the highest I've seen is 215 going uphill (long steep grade).

So far, with the new inline setup, I can tell that the temps ramp up and cool down faster. Cruising 55 with the AC on is about 199-201 and highway was around 204-206 (75mph). Idle seems slightly better at abI'd like to geeout 199-201. All of these are with the AC blowing full blast and only 101 degree ambient. Big cooling trend in our weather today. Had to put on my parka.

It doesn't seem like a drastic difference so far over the gray stat, but it does react faster and is slightly (2 degreesish) cooler.

If anything, it does make changing a thermostat way easier.

I'll report back after I hit some 110+ degree temps on the highway if there's any appreciable difference.
How old is your radiator? I've got a <2 y/o Nissens. I'd like to get an Allisport, but they don't seem interested in answering emails.
 

mbrummal

Well-known member
Jan 23, 2009
2,893
22
Willow Spring, NC
You could get a custom radiator made to mount in place of the stock one if you have an old one you could send in as a pattern. I had one made by Griffin but C&R or some others could make one too.
 

FatMcNasty

Well-known member
Mar 28, 2006
204
63
Southern Oregon
Ya, got it in. looks ok at first but when you get ready to put it together. Ya find what's wrong, uh the side pins are in the wrong spot. and its too tall!
 

Attachments

  • 20210629_170851.jpg
    20210629_170851.jpg
    181.7 KB · Views: 17
  • 20210629_170926.jpg
    20210629_170926.jpg
    166.5 KB · Views: 17
  • 20210629_171019.jpg
    20210629_171019.jpg
    212.1 KB · Views: 16
  • 20210629_171026.jpg
    20210629_171026.jpg
    161.6 KB · Views: 17

FatMcNasty

Well-known member
Mar 28, 2006
204
63
Southern Oregon
Are you going to be able to use it at all?
With a lot of work, yes. I contacted the seller last night trying to get an exchange or refund. and he comes back with how about I refund $35 so you can get it fixed in a local shop.
To make it work, it needs the pins/cut and pulled out new holes drilled then welded in place. next is the fan shroud. with it being crazy tall I have nowhere to clip the top to. bottom hooks need moved up 3/8 of an inch. then the top needs clip cuts put in 3/8 of inch lower. No shop is going to do that for $35.
Then my line of thinking is, if they screwed up the easy parts, is the oil coolers built right/sealed inside. Ill test that tonight and send him back a counter offer that will be enough to get the work done. Well see where that goes.
 

robertofollia

Well-known member
Aug 3, 2005
555
2
My home is where my Disco is
Excellent write up. we have not had any issues in hot Spain, but the inline thermostat conversion is indeed a very interesting upgrade: save problems, eliminate surplus parts and gain reliability. Best regards and thank you for sharing
 

donniefitz2

Well-known member
Sep 15, 2020
138
56
Scottsdale, AZ
fitzventure.com
To follow up on my last post, this modification is worth doing in my experience (1.5 months). Again, compared to the LR gray soft spring thermostat, this inline kit runs pretty similar temps, but just a tad lower. Nothing drastic. What I did notice is, once you hit sub 90 degrees ambient, the inline will run about 5 degrees cooler than the gray stat (183.1 vs. 188.5). Honestly though, that's not when it matters so that's a wash.

The inline kit does react faster. After idling in traffic in 108+ ambient, I'll see 199-205 and it will fall back down to 197 in a few seconds once I get moving.

Where I see little difference is huge mountain climbs (25% grade for miles and miles. Mt. Ord if you're from AZ, you know) in the heat (105+). The inline is about the same as the gray. I'll see 210 and as high as 215 with both. That's when I hit the magic econ button and kill the AC compressor, bringing temps back down to sub-210's and my family complains about how hot it is. But then I point out all the fools on the side of road at the top of the hill with their hoods open because they overheated. Suck it up kids! It's not just Land Rovers.

Anyway, this inline stat is good, if only slightly better then the gray one. If anything, I do like it's simplicity. It's staying on my Disco.
 
Aug 20, 2007
2,727
45
Nashville TN
To follow up on my last post, this modification is worth doing in my experience (1.5 months). Again, compared to the LR gray soft spring thermostat, this inline kit runs pretty similar temps, but just a tad lower. Nothing drastic. What I did notice is, once you hit sub 90 degrees ambient, the inline will run about 5 degrees cooler than the gray stat (183.1 vs. 188.5). Honestly though, that's not when it matters so that's a wash.

The inline kit does react faster. After idling in traffic in 108+ ambient, I'll see 199-205 and it will fall back down to 197 in a few seconds once I get moving.

Where I see little difference is huge mountain climbs (25% grade for miles and miles. Mt. Ord if you're from AZ, you know) in the heat (105+). The inline is about the same as the gray. I'll see 210 and as high as 215 with both. That's when I hit the magic econ button and kill the AC compressor, bringing temps back down to sub-210's and my family complains about how hot it is. But then I point out all the fools on the side of road at the top of the hill with their hoods open because they overheated. Suck it up kids! It's not just Land Rovers.

Anyway, this inline stat is good, if only slightly better then the gray one. If anything, I do like it's simplicity. It's staying on my Disco.
excellent review and I agree 100%. I see similar on mine in similar conditions.