CRACKED BLOCK? Read This!!!
 

Well, I just got in from a nice, LOOONG drive with my 2004 Disco. The temperature never climbed above normal, and I stayed warm the whole time.

Yes, this is the SAME engine with a cracked block, that was overheating if I tried to drive it and turn it off, then on repeatedly (ie, going to town and making some stops).

How did I do it?

I noticed that my problem was that my thermostat would not open when the air pocket created by the crack would get around to it.

So what did I do?

I have 3 thermostats lying around from all the testing I did, so I took one, and placed it on my work bench so that the "Y" faced up. Looking down the vertical pipe, you clearly see the thermostat. There is a horizontal metal "bar" going across the middle of the pipe, and right below that is the copper "guts" of the thermostat. If you press on the copper with a screw driver, it will go down toward the bottom of the "Y". (In other words, it opens so water can flow through).

Test it by pouring water into the top of it- none comes out the bottom.

Well, remember the horizontal piece I just mentioned? If you put a flat screw driver on that, and tap nice and hard with a hammer, you can see it start to bend. Keep tapping, and it'll make contact with the copper. Keep tapping, and it will probably split in half, with both halves bent down into the copper.

Reposition your screw driver up higher on the metal bar, and tap on both halves until the copper is jammed down as far as it'll go- that is, until the thermostat is stuck open, and cannot close.

Test it by pouring water into it from both sides- it should flow freely! Mine did.


And, after putting it back on and bleeding the coolant system, this thing is freaking SET.

Here's what happens:

Basically, your engine can't get up to temperature. The thermostat cannot function normally, and open and close to keep the temperature at a nice (I don't know, 180-210?) degrees. Now, when it idles, it MIGHT get up to 180, but as soon as you start driving and wind starts whipping, it drops back down close to the blue.

Is this a bad thing? Well, it's a lot better than having an over-heating disco! I have at worst luke-warm air blowing from the heater, and at best, nice, hot heat.


NOW- I think it's going to depend on HOW your block is cracked that either allows, or disallows this method to work. Mine is cracked in such a way that doesn't allow any coolant into the crank-case. In other words, mine is burning the coolant, but at such a slow rate, I think I could drive with this "open coolant system" for years and years.

I'm pumped about this, and though I'm still getting a new engine, I'm thrilled that I'll be able to drive it until the new block comes in.

Pat

Just, for the love of God, keep an eye on your oil. That crack could get worse.

Do you really think it could get worse? If it was caused by intense heat, I sort of feel like, given that the engine can't really warm up, it won't get any worse.

I'll keep checking the oil, but since I'm getting a new block in a couple weeks, what's the harm?

Could it hurt the heads, if I get coolant in the oil?

Could it hurt anything else that I'll have to put on the other engine?

Pat

Well, the first rule of thumb with Land Rovers is to have spare parts. Do you have to send your short block back as a core? If not, I would keep the crankshaft out of it. You can sell it, keep it, do what you will with it, but it's always good to have a spare.

If you have to send yours back for any sort of a core charge, then never mind.

No, I don't have to send my block in. That's a good idea; I'll keep the crank if it's not too much trouble.

Since you block is shot anyways you may want to try one of those head gasket fixes in a bottle like steel seal or blue devil. I think the blue devil has a guarantee so if it does not work you get your money back. If your block leak is small enough it may plug it up.

I will say that if you run a cold engine, it will stay in open loop and overfuel the whole time you are running it. This will cause carbon build up and heat your cats a little more than they are used to. If you throw a coolant leak into the equasion, you could melt your cats.

Your heads do have carbon cutters, so you should be ok for a couple of weeks, but check your oil constantly! Start getting coolant in it and you will kill your rocker shafts.

Great advice, OKD- I have never thought about the catalytic converters.

I won't be driving it much- just to my office 8 miles from home a few times per week for the next couple weeks, until I leave for Colorado (hiking).

By then, she'll be back in the shop for the new block.

THANKS!

i just did the same thing before reading your post. I believe its more likely a headgasket issue that is obviously fixed if you put a new block in it. I would be highly surprised if your block was cracked. I just put a screwdriver in mine and bent the sealing plate in the thermostat. I cant believe that more people havent done this with some success. It allows some coolant to flow thru all the time so that the air bubbles dont get locked up in the thermostat housing. Mine runs just above the blue line now and thats great for me. heat doesnt work super good like it did but at least this thing doesnt overheat now. It cant because its in open loop. Worst thing that can happen now is i have to fill the overflow every once in a while. I believe alot of people on this forum arent really car guys and listen to what others have said and get the trusty headgasket fix and then the problem persists. Im just not one of those guys. good job on fixing it or at least band aiding it without throwing money at a vehicle that is not worth a block change in a truck worth less that a block...lol cheers Kevin

SWEET- I'm glad I am not the only one. I noticed that if I run my heat on "MAX" with the fan set two notches from the bottom, it holds a pretty good operating temperature and gives me decent heat. If I put it on MAX with the fan cranking, it gets too cool.

Just above the blue- a LOT better than in the red, eh?! HOAH!

But, my truck is definitely worth a new block- I'll be doing it in a few weeks.

You could always put a piece of cardboard infront of your radiator to help keep the engine warm.
Just like on over the road trucks, except they use basically a tarp specially made to fit their truck.
When I drove truck I just used cardboard, stuck it right behind the grill, engine stayed nice and warm, removed it come spring.
Next winter new piece of cardboard.

Very nice job. I'm glad u didn't go by the usual advice "don't mess with the stat or ur asking for it" advice I've seen on alot of different forums. My truck is a 2000 disco 2 with 110k on it and I believe most bluebooks value these at around 4500 and I think that's what a shortblock costs minus the labor time if u have it done. Hardly a wise investment at my stage of the game. Did u get a chance to drive it on the highway. That will be the real test I believe. Just exactly how did someone come to the conclusion u have a cracked block. Unless it's visible or spewing out the side do not trust this diagnosis wihout seeing it with ur own eyes. It could just be a headgsket leak and could be checked by backing off the rocker arms so all the valves are shut and apply compressed air to the cylinder via the spark plug holes. Look for air entering the coolant system which u should be able to see in the overflow since u have the stat altered. But u kinda have to be a car guy to do this. Lmk if u decide to try this method and I can walk u thru it over the phone. I'm so happy I don't have to worry about his sucker for a couple months. Cheers. Kevin

Man, I guess I don't know, friend. The Rover dealer said it's a crack, so I assume it is just the crack.

I just had the head-gaskets replaced, but man... I don't know. I think it's burning a little bit of coolant in #7, and it seems to put out more exhaust "smoke" than the 2000 does.

Assuming I DO have a crack, I think you're right: I feel confident that I could drive this for a year the way it is. I have to make a trip to Wisconsin on Thursday, and if I could have a couple more weeks, I'd drive it there... but I don't feel confident in it YET.

But more good news: I drove on the freeway today, cruise set at 79. The engine stayed just below the normal operating range, and it ran perfectly. I had all the power in the world with this baby, and the heat wasn't that bad.

It worries me that I might not actually have a crack... Do you think the dealer could be wrong? Do you think YOU have a crack? Did you use your rocker-method to test it?

I assumed that the dealer took the heads back off and did a inspection Pat.
Without a visual inspection how can they tell?
There is a way to test a block for a cracked sleeve, or a crack anywhere but the heads have to be off of it as far as I know.

Spike- you mean there is NO way to check?

Because it only took them about 45 minutes of diagnostics....

I'll call Jason back at the Sharpe collection tomorrow and ask.

Man I would love to be u right now. I would go to the dealer and kill the guys intelligence in 10 minutes of questioning. First I would say just how did u find the crack. He won't have an answer for this. Where is the crack? Since he's so sure there is a crack surely he would know. What cylinder has the crack? How do u go about diagnosing this crack other than overheating? Shock u fixed in 20 minutes and a screwdriver. Alot of rover dealers are going to give u the same answer because hey if u buy a motor it's a forsure headgasket change and all gaskets new. Also ask him how he knows it's not a head crack? He won't have an answer to this either. Did he go thru the coolant system to make sure there isn't a bunch of junk in it. There are tons of answer u are entitled to after u have spent 300 bux in getting it to their shop. Most dealerships are crooks and without people who don't know engines they will be in business a long time. Really happy for you.

They didn't do anything in 45 minutes except feed u a line of crap. I don't care what test they did it can't be done in 45 minutes. They will let u bring it in for the cracked block. Replace it along with all the gaskets inspect the heads to be sure they didn't miss something and charge u 5k. People fall for this crap all day. Think about it. With a crack engine diagnosis they cover all their bases and if the heads are cracked they come to u and say well the motor ws crack and that cracked the heads so now we need more money from u to fix it. Now it's an entire new engine. Tough for them to be wrong at this point. Lol.

Man, you're right...

Friend, you've given me a LOT to think about.

Please tell me that u are going to ask the dealer some of the questions I said earlier. I am a dealer mechanics worst nightmare. I sometimes ask them to check over stuff for fun with my wifes Mercedes ml430 the Benz dealer comes up with some crazy stuff. They finally realize now not to feed me crap lime they do the other lost sheep coming into the dealer with a Mercedes. Let us know what u find.

Yeah Pat without pulling the heads I dont know of any way they can check.
Other than pulling each spark plug one at a time but even then without it leaking coolant into the cylinder they wont know.

I have been looking on youtube for the video that I saw before on how to check for a crack behind a cylinder liner but of course I cant find it.

Thanks very much, Spike- I'm a but comforted that my trusted Mechanic tried everything he could think of, and he was certain that it wasn't a gasket problem.

He said that he stuck a camera in the #7, and it WAS moist looking, but he couldn't tell what the fluid was or where it was coming from.

I'll call Sharpe today and see about the diagnosis. I don't actually know if they spent only 45 minutes on it or not- but before I had it towed, he said the diagnosis would only take 45 minutes or so.

I did have it towed in at about 3pm, and I got the call at 5:30, but I assumed they just had a few cars ahead of me.

I'll let you know.

PS- The only troublesome thing is, my mechanic said he would have noticed a crack or a slipped liner when he pulled the head off, and he didn't notice anything.

PPS- My Rover runs spectacularly right now... So weird....

Cracked Cylinder Sleeve Diagnosis
 

Rovers are known to have cracked sleeves after multiple overheates. If you have had problems with overheating and have had your headgaskets repalaced than it s very likely to have a cracked sleeeve.

Your DEALER can perform a Block Test to determine if there is exaust gas in the coolant. IF there is then most likely there is a cracked sleeve. Now of course I am assuming you have had any other obvious coolant leakes replaced, which sounds like most of you have.

So the 45 minuts worth of time at the Dealer is well woth the Money, especially if you have been true to them on what you have done. Yes they could take the heads off and inspect, but wouldn't you rather be up front with them and spend a diagnosis charge and have them run a Block Test or do you wan them to pull the heads off and tell you after $700.00

Sounds like you have a answer good luck

Exhaust gases in the coolant doesn't indicated a guaranteed crack block. This could easily be a headgasket issue. It's post like yours that confuses non car guys. Do the landrover motors we are working with have sleeved cylinders? Why. I have and aluminum motor in my racecar and it has sleeves but only because it's aluminum. Why would u sleeve an iron block? Will need a landrover tech to answer this I'm sure. Thanks guys.

The rover block is aluminum...

Knowlage101, I thought rover sleeves were "dry". The dealer did a combustion gas test at best. I dont think I would let that DEALER work on your rover unless you have very deep pockets!!!

Do you own an LR? They are all aluminum......That is why Rover engines are so popular for small rally cars. You can get 5.3cu/in out of these things and they are light as heck.

Just like OKDGuy said, the Rover 4.0 is the Chevy 350 equvilant in Europe.
Imagine a MG Midget with a bored and stroked 4.0, that would be fun.

To better enhance Rovers off road abilities the engine, transmission and transfer case are aluminum.
All the weight is in the boxed ladder frame and solid axles, with everything else being aluminum (including the body) the truck is bottom heavy not top heavy.
That with coil springs on all four corners give them a 43% roll over angle.
Not to bad for such a narrow truck.
And they are narrow for a reason, ever try to blaze your own trail in a big fat H1?