D2 - Overheat - Head Gasket, etc…..

[Contractor]

So I don't post much here mostly because I don't own a Disco………but a guy I work withs son does.


2002 DII - Here is what I know and what I have done:


He was driving the truck to a shop to replace the power steering pump. The truck overheated and had been running hot and the son kept driving it. He drove it to the point that it basically stopped. I was told that coolant was pouring out of the motor and it literally would not progress forward any more. I know it has had a history of running hot……i.e. the last couple of weeks….he literally just bought it.

Because I am a glutton for punishment, I agreed to pull it apart and see what might be wrong. I assumed the head gasket(s) were cooked and at a minimum they would need to be replaced.


I have torn the motor down and found the following:


- Both head gaskets are intact and don't seem to be the culprit.

- There is coolant in three cylinders (2,3,4)

- I drained the coolant before doing much or anything and only about 1.5 quarts came out at the most.

- Intake gasket looked fine

- It appears that someone has replaced the water pump at some time or another, it literally looks brand new and is nice and shiny.

My path forward is taking the heads and having them checked for flatness and basically getting a valve job. I feel like since I am in there I should pull the front cover and at least replace the gasket…..pull the oil pan too?

I know absolutely nothing about these motors and would love some guidance. I know enough to be dangerous, but would certainly appreciate any tips that someone might be willing to provide. i want to make sure I don't miss a step and I want to make sure I actually try and correct whatever it is that is wrong.

Any guidance would be appreciated.

I drained the coolant and then pulled the intake for my sequence of events.

Advice for steps forward would be appreciated.

Will

 

[riceybean]

Sounds like what I just went through. Mine turned out to be the front cover gasket. Easy to tell as all the coolant was in the oil pan. Yours sound like a head gasket. Especially with the loss of the coolant and running it hot, which they do not like, before it was opened. Only thing I can think of..

 

[Contractor]

I thought head gasket too, but they both look fine. Perhaps the head warped, but did not damage the gasket?

I am thinking about taking off the front cover and oil pan as well just because I am already this far into it. I'd hate to get it all back together only to have to start over again.

 

[jymmiejamz]

If there is coolant in cylinders 3,4,5, or 6, you have either a cracked head (unlikely) or a cracked block (likely). There are no cooling jackets sealed by the head gaskets on those cylinders.

Did you try running the engine before disassembly? Its very difficult to diagnose an engine issue with it taken apart unless you find a very obvious issue.

 

[Contractor]

I ran it prior to pulling it apart but only long enough to drive it on and off a trailer. Based on the descriptions I was provided with I assumed head gaskets.

The coolant is in cylinders 4, 6 and maybe a little in 8. 1, 3, 5 and 7 are dry.

I don't think the coolant would of come from the disassembly process as I drained it and I would bet less than 1 quart came out total. I guess I mean I don't think it could of leaked out from the intake or any other coolant hoses.

Picture #2 shows the coolant in the cylinders.

If the block is cracked, how would I go about figuring that out? In hind site I guess I should of filled it up with coolant and let it run again, but I was a little worried about screwing it up more. If it's a cracked block I don't want to sink a bunch of money in it only to find out it was all for nothing.

 

[jymmiejamz]

Just look at where the coolant goes through the head and block. The cooling passages are on the ends of each head. If coolant is in the middle cylinders, the block is almost certainly cracked.

Was it misfiring badly and smoking when you pulled it off the trailer?

 

[Contractor]

No misfire and no smoke.

I don't see any obvious cracking around any of the passages. I have also drained the oil and it seems to look ok, not cloudy or milky that would indicate serious coolant mixture.

I agree with you though, I don't see how coolant could of reached those cylinders otherwise. I think that so much coolant leaked out of the truck that the chances of me accidentally spilling coolant down there during disassembly is very, very low. Nothing came out of the hoses or really anything other than the radiator drain plug.

 

[riceybean]

The first time I did the heads on another Rover I had coolant in the passages even after draining it. And my head gasket blew out from the back of the head on the passenger side. Just a thought.

 

[P38]

No misfire and no smoke.

I don't see any obvious cracking around any of the passages. I have also drained the oil and it seems to look ok, not cloudy or milky that would indicate serious coolant mixture.

I agree with you though, I don't see how coolant could of reached those cylinders otherwise. I think that so much coolant leaked out of the truck that the chances of me accidentally spilling coolant down there during disassembly is very, very low. Nothing came out of the hoses or really anything other than the radiator drain plug.

It can sit in the galleries, it's not guaranteed to drain down. The vulnerable part of the gasket is the back of the head. I did my sons and had the heads checked for flat and then skimmed 15 thou. Replaced the pumps, hoses and t'stat and everything going like a train so far, and that includes highway miles and pulling a 23' boat/trailer.

 

[kcabpilot]

From all the research and reading I've done on these motors my conclusion is that if you have a cracked block it's going to be behind one of the liners so you're not going to be able to see anything in the situation you're in. The only thing you might be able to do is to fabricate some block-off plates for the front and rear coolant ports then pressure test the block. If it's leaking you might be able to locate it by spraying soapy water around the rims of the cylinders and looking for it between liner and block bore but there's no guarantee of that. There is a YouTube video online of someone successfully doing this but it's on a bare block from which they have removed the liners.

 

[Hubacek]

Just out of curiosity, what does the oil look like? Check out p. 29 of this link. You will find most of the content in that chapter applicable to your scenario here.

https://books.google.com/books?id=g...&pg=PP1#v=onepage&q=arp stud kit rover&f=true

 

[Rockbeard]

if you look closely at the cylinder bores, can you see if a liner has dropped down a bit ? i'm not sure if that possible to see to see with the naked eye, but hey, it may be and if so. a new short block is in order with top hat liners installed. MOST of the time, it's a good ol head job needed, and yes, get them rebuilt and milled at a good machine shop. there's a special tool used to determine if the block or cylinder liners have a crack in them but the engine needs to be fully assembled to perform this task. there's a lot of smart techs on this site and they give good advise. my personal fave is DISCOSTEW. give him a shout or i'm sure he'll read this and chime in. good luck

 

[jymmiejamz]

if you look closely at the cylinder bores, can you see if a liner has dropped down a bit ? i'm not sure if that possible to see to see with the naked eye, but hey, it may be and if so. a new short block is in order with top hat liners installed. MOST of the time, it's a good ol head job needed, and yes, get them rebuilt and milled at a good machine shop. there's a special tool used to determine if the block or cylinder liners have a crack in them but the engine needs to be fully assembled to perform this task. there's a lot of smart techs on this site and they give good advise. my personal fave is DISCOSTEW. give him a shout or i'm sure he'll read this and chime in. good luck

The liner has nothing to do with the cooling system. A liner that moves only creates noise.

 

[Contractor]

Thanks for the advice.


The owner of the truck has decided that he is just going to sell it. At the end of the day he's not an enthusiast like most of us and is a guy that just happens to own a Rover.


I have it listed over on D90 and will make some time to list here this morning if anyone is interested.


Seems like a good truck to me otherwise.