I've not heard of many 4.4's getting "cooked" beyond head gaskets. I find it interesting that the Indy suggested head gaskets and then pulled the engine. Seems odd. Now you don't have the advantage of running it and diagnosing. Were you able to talk to the Indy, or did you just get the story from the seller of the HSE? I've just never heard of pulling an engine to change head gaskets.

If it is just head gaskets, I'd have the heads checked and re-install them. 70,000 miles is a low mileage engine.

Having said all that. Can the 4.4 overheat? Yes. The cooling system is fragile. The radiator is under spec'd; the reservoir is known for cracking, there is a small cooling hose on the backside of the engine which is known to spring a leak, and on and on.

I know the above doesn't help much, I hope someone else can chime in here and give you some solid information.

 

I've not heard of many 4.4's getting "cooked" beyond head gaskets. I find it interesting that the Indy suggested head gaskets and then pulled the engine. Seems odd. Now you don't have the advantage of running it and diagnosing.

I suspect that the Indy knew more than he was letting on. The car had been serviced by him a couple of weeks prior to this happening so I am thinking perhaps he realised he was at fault somehow and was trying to fix it. He did mention that there was very little water in the cooling system so its quite likely that one of the weak points you mention failed. But the car was running when it was brought in so maybe its not too badly damaged.

One "expert" I spoke to said that the piston rings lose their strength when they get too hot so a ring change would be in order as well as the gasket change - and the crank bearings etc. etc. But I need to open it up and have a good look. Unfortunately I am away from home for a while so it will have to wait. I wonder if the VCC system gets affected or damaged by too much heat.

This is going to be a steep learning curve for me. So many questions to ask and I dont even know what they are yet :?

 

If the previous owner really cooked the engine, it's possible the block is no longer within "specs". I would think you need to disassemble and begin measuring everything. Crank bearing saddles, cylinder bores, head deck, as well as measuring the heads. A good machine shop should know where to begin. I cooked an old 3.9 Classic engine when the temp gauge failed, I mean I really cooked it, driving thru the mountains. I pulled everything apart, sent to a machinist, had him measure all the specs for block and heads. Block was fine, had to skim the heads, then I put it all back together. I've since put 100K on my rebuild.

 

Yep...the heads are the key. With todays synthetic oils, I don't think you can cook the bottom end without running it out of oil first. The top end will fail long before the bottom end.

The heads get hot first and worst, so they will warp in an overheat. That's also why the head gaskets usually fail. The next to fail are the pistons in the bores. The aluminum pistons expand faster than the cylinder walls, so they start to scuff, bind, and eventually lock up. But, scoring in the cylinders is easy to check with the heads off.

If the cylinders ARE scored...I'd throw it away, as that means it heated enough to seize up, and it is just not worth messing with after that.

Hope it's not as bad as you fear!

John

 

Yep...the heads are the key. With todays synthetic oils, I don't think you can cook the bottom end without running it out of oil first. The top end will fail long before the bottom end.
John

There is a M62 out of an 03/04 RR sitting at a friends shop that ran hot, and actually warped the block. The complete engine is toast. It can happen. Need to check the block and the heads to be safe.

 

Thanks for the tips. I really need to try and get more info from the seller and the Indy regarding the overheat. The seller did say that it was smoking so much that people were staring. But what is smoking? To a guy who knows nothing, steam looks like smoke. From the engine area or the exhaust pipe? If the piston or pistons did seize temporarily could it have caused enough damage to make it smoke till people stared?

I have read that if the bores get scored its bin the engine time as John said. I hope not but its very possible. Anyway the picture is building so please carry on with the input. By the time I get home in a month I am going to be a guru on the M62 motor `)

 

There is a connector for the heater hose that is located directly on top and at the rear of the engine. My local RR parts man says it crystalizes and then breaks so often that they replace it as a matter of course every 50k miles or so. I had mine blow out, and it was REALLY impressive! The coolant sprays all over the engine and exhaust, and the whole car goes up in smoke.

When it happened to me, I was 3 miles from the house, so I pressed on with my eyes rivetted to the temp gage. The gage never moved from center, and I made it home. The amount of steam smoke was just amazing. Even after I replaced the fitting, the car still smelled like antifreeze for months!

I hope yours ends up being that simple...if the PO stopped within a few miles of the steam appearing, the motor may never have overheated at all.

John

 

... so I pressed on with my eyes rivetted to the temp gage.

Coolant temp guages are only accurate if there is coolant in the system. With no coolant in the system your cylinders will continue to heat/overheat your heads and block to and past melt down or warpage with the temp guage never moving.

NEVER EVER drive a vehicle after a coolant failure... NEVER.

 

I got hold of the seller today but he was very vague about the whole thing. He said that smoke started coming out of the exhaust sometimes and then after a while it got worse but the Indy was very busy so he did not take it in straight away.

That really helps.

As I said he is not a mechanical guy at all. You put petrol in that hole near the back of the car and the oil and water gets checked at every service so whats the point of checking it yourself.

Oh well. Maybe I will be lucky but not banking on it. It was not a catastrophic failure if he carried on driving it for a while but whatever was happening was getting worse. I wish it was cut and dried so I can just organise a replacement motor and be done with it. But I will regret that if I get home to find little wrong with it.

 

I've read through all this. If it were my car. I'd check to see if there is oil in the engine, I'd do a leak down test on each cylinder, and stick a bore scope down each cylinder. If that checks out I'd stuff that engine back in and start it up. Don't forget to put coolant in it first..... LOL.

 

I have odered my camshaft timing tool kit for the M62 motor. Next on the list is a boroscope. (been wanting one for years anyway). And I am trawling the internet for anything remotely connected to the M62. (not forgetting RAVE). I have built up an impressive collection of articles from manufacturers instructions to DIY experiences on fixing most things on these motors so I am getting well prepared for my return home.

Worst case scenario is I will slap in a used motor but if I am lucky the motor may be salvageable.

Another question. With the motor removed and the electrics disconnected what about the steering lock? I will be needing to manouver the vehicle to get it into my workshop which will be a pain if there is no steering.

 

The steering lock is an electric solenoid. It will need power to unlock. That said, I don't know what it will do with the engine removed if you reconnected the battery!?!

Option 2, if you are just moving it around a garage is to use a floor jack with wheels to lift the front and act like a dolly.

Be sure to keep us posted as you work on it!

John

John

 

Sorry, still do not believe it. It's less a matter of common sense and more of physics. What's more, seems my case proves it, while I find that most drivers couldn't find the temp gage to save their lives. So, doesn't matter what owners have sworn...if you lose all your coolant and the gage doesn't move, then your gage is broke in addition to your engine meltdown.

John

 

Sorry, still do not believe it. It's less a matter of common sense and more of physics. What's more, seems my case proves it, while I find that most drivers couldn't find the temp gage to save their lives. So, doesn't matter what owners have sworn...if you lose all your coolant and the gage doesn't move, then your gage is broke in addition to your engine meltdown.

John

Yes, it is a matter of physics (heat transfer), that is why the coolant temp gauge is not as reliable if you lose your coolant. The sensor should be able to measure temperature where it is located, but that may lag significantly behind other parts of the engine if the heat generated is not being efficiently transferred into the coolant anymore (relative to coolant, air is terrible at heat transfer) and not being circulated by the water pump. If the temp gauge starts getting above normal and you are losing coolant, you shouldn't take chances by continuing to drive.

I've had hoses pop off before (not on my RR thus far though) and always shut down immediately and pull over. It is generally pretty easy to fix such things on the side of the road anyway at least well enough to drive it the rest of the way home afterwards to do a proper coolant flush and replace additional stuff... and even if you needed something that is a bit harder to find in a pinch like the expansion tank... $100 for a tow is a lot cheaper than paying for a new engine, or head gasket, etc. Just not worth the risk.

 

Finally got home and had my new sick Range Rover delivered. Have started stripping the motor and can find no damage so far. (except for the sludge). Heads are off and no sign of blown gaskets. Heads very slightly warped but nothing that cant be skimmed. Bores look perfect to the naked eye except for some slight discolouration which is my question. Should the colour of the bores be uniform? What does it mean?

The pic of the engine and its parts are how I received it - half stripped.

 

Send more photos of the GT

 

How about this?

 

Be still my heart!!! Car porn! I love it!

 

Very easy to forget about the overheat with that beast around but I pray for minimal damage. Will be interesting to read how out of round the bores are. That may help to answer the color question.

 

The discoloration of the bores looks very much like injector spray pattern. However, it could also be an indicator of a previous tightening of the bore onto piston due to lack of cooling (this is possible due to the amount of sludge in that engine! This could have been a contributory cause for the over heating, and it looks carbonized but difficult to tell from the photos). Only way to check will be compression check or if you can, perform a dimension check on the cylindrical component of the measurement to ensure that there is no damage. Then again, it could be blow by which would contaminate the sump oil causing the sludging all over the engine. At the very least perform a compression test to determine if the rings are OK.

If the heads are warped slightly, then very likely this could be the only issue as the heads are the weakest link by far as you say it ran for a while after smoking (block is proven robust but they can twist under heavy over heating!). Ensure the block surfaces are as they should be, skim the heads, flush the hell out of the block and make sure there are no tight spots when rotating the crankshaft then rebuild. I think you are lucky.

 

I have stripped the motor completely and what I have found is very strange. There is no sign of any damage at all. Crank, bearings. bores etc. etc. look 100%. Crank was spinning freely prior to removal which is a good sign that the block is not warped. If I did not know the previous owner had a problem I would say the motor is in very good condition - except for the sludge.

So my plan is to give it a thorough clean and take it down to my local machine shop and get everything measured. If its all within limits I will fit new bearings, rings, etc. Will also inspect and possibly replace timing chain and guides. Get the heads overhauled and put it back together.

I did notice a lot of oil in the inlet manifold and I am thinking that perhaps the smoking that the previous owner mentioned was a leaking seal or diaphram. If that is the case the garage that pulled the motor messed up badly with their diagnosis. Stranger things have happened I guess but will only know for sure on Monday once everything is measured.

 

If the head is not warped, then perhaps there were issues with the PCV system, a known weak point, but very cheap and easy to maintain... I suspect it probably did have an overheat though because otherwise why would it loose all that coolant? Perhaps you did get lucky and the block is OK though. Doing most of the work yourself aside from the machine shop stuff the cost will obviously be far less than what the previous owner would have paid so you probably got a good deal. You'll find out soon

 

Regardless of measuring, surface the heads and deck the block. No point surfacing the heads if there is a slight chance that the block needs decked is there? I automatically do it to EVERY aluminum block I rebuild.
Honing on the cylinder walls, check the line bore and call it good, although I seriously doubt anything bad, worth checking IMHO. I always get a crank grind on aluminum motors too, and they grind the crank to each individual bearing when torqued down. This makes for a 110% correct fit in the aluminum.

And as far as the temp sensor argument goes, how can a temperature sensor that is made to go into a water jacket read correctly when there is no water (coolant) in the jacket? Of course the tempersture gauge reads way off when there is no coolant, as the sensor is all but useless at that point isn't it? Seen it for myself in big rigs and cars/suv's.
Martin

 

Just curious Ghur, when you scrape the black junk on the cams, is it soft goo or hard coke?

John

 

Its like like a soft crunchy goo. Like crunchy bovril.................

 

I don't know about the bores. These cylinders are nickel plating over aluminum. Your best bet is to take the block to a decent machine shop that has a good bore micrometer. They can check the upper portion of the cylinders to see if they are out of round. That is the area that will warp during an overheat. It only takes a few minuts to check with the right tool. Also look very closely around the top of the bores, and especially between the cylinders, for hairline cracks.

I have no experience with nickel plated bores. I don't know if they are repairable or not. I know they would not be by the old traditional machining techniques, but that does not mean there isn't a way...

Soft goo is sludge which builds when engines are run frequently for short distances without getting warm enough. You don't usually see that much unless the PO was using a non-synthetic oil. If it gets crunchy hard...could be an indication that it got hot, which is not a good sign. The coking is not definitive, though, just an indicator.

Your heads are similar. Look at them very closely around the mating surface to the block. You are looking for any tiny hairline cracks. If there are none, they are rebuildable.

Best of luck

John

 

Thanks for the gen. I will get the bores checked on Monday and make sure they do as you suggest. I checked the heads again this morning after stripping and cleaning them and there does not seem to be any warp. Will obviously get them checked by the experts as well.

Cleaning the sludge is a very messy business. Is there any clever solvent that will disolve it after an overnight soak?

I contacted a reputable machine shop yesterday that specialises in BMW motors and they say they have re-sleeved many of these and similar motors over the years without any problems using standard sleeves. But I have also read on the internet that its not a good idea. But will wait and see what happens on Monday and then look at other options.

 

Thanks for the gen. I will get the bores checked on Monday and make sure they do as you suggest. I checked the heads again this morning after stripping and cleaning them and there does not seem to be any warp. Will obviously get them checked by the experts as well.

Cleaning the sludge is a very messy business. Is there any clever solvent that will dissolve it after an overnight soak?

I contacted a reputable machine shop yesterday that specialises in BMW motors and they say they have re-sleeved many of these and similar motors over the years without any problems using standard sleeves. But I have also read on the internet that its not a good idea. But will wait and see what happens on Monday and then look at other options.

I bet this engine could be re-assembled as is, put in the RR and run forever.

Having said that, here is what I'd do. Take the heads and block to a machine shop. Have them "boil" them in their tank and check the specifications. I bet they tell you they are okay. By the way for a myriad of reasons having the machine shop dip them will be much better than you trying to clean them. Then reassemble the engine, (make sure you check the VANOS system and replace the timing chain), put the engine in the RR and have fun.

 

I don't know of any soaking solvent, except maybe "Gunk". Carb or brake cleaner will disolve it almost instantly, but it is still a messy job that has to be done with a lot of rags and paper towels.

Machine shops all have a heated solvent tank, where they can immerse the heads - or even a whole block - overnight. It removes all but the baked on sludge. Of note...their tank gets a lot of sand, dirt, and grease from other parts. If you let them clean your heads, you should totally dissasemble them and clean all passages with carb/brake cleaner and comressed air afterwards. A little sand from the tank can do a lot of damage in one of the cam oil passages.

It'll be interesting to see how round the bores check. There is nothing wrong with sleeving the bores, except it may cost as much as a junkyard engine to do all 8.

Good luck at the machine shop!

John

 

A good machine shop will always clean the parts themselves regardless of looking clean. The lubricant they use in the machinery is very expensive, and they dont want it messed up with old dirt etc.
They can, and should, pressure check the heads, this is very standard practice. No need to spend hours looking for hairline cracks etc, just have them pressure checked and surfaced. Same with the block, pressure check and deck the block. Again, both are extremely standard procedures on a GOOD engine rebuild. Looking for cracks etc is all but useless on modern motors, get them pressure tested and be done with it.
For parts like cams etc, I use Purple Power in my parts washer. You can leave them soaking for about 10-15 minutes, then use a soft brush (paint brush etc) and scrub them. Then rinse thoroughly with clean water and blow dry. Dont be tempted to leave aluminum parts in there overnight etc, the results can be very bad! On bare blocks, I leave it on the engine stand and spray Purple Power onto it, brush it in, then pressure wash.
Have a look through this thread I made on the first (IIRC) P38 motor I tore down, along with the associated gunk, an then cleanup.
http://www.rangerovers.net/forum/7-range-rover-mark-ii-p38/32665-motor-tear-down-follow-along.html
After machining work, I always use warm water and dish washing soak to clean the block/heads, etc. Then use the air gun to blow dry the parts, as well as blow out any left over machining gunk.

Martin

 

Dye penetrant is available from any decent welding or bolt supply company, and is easy for any novice to use at a very reasonable price.

Eddy current crack testing is available at top end machine shops...or most aircraft mechanic shops. Not for untrained use and rather expensive. Same for sonic testing and equipment. Here in Fort Worth, we have Bell Helicopter, Lockheed, and General Dynamics. I have, in the past, even sweet talked them into X-ray testing some of my parts.

Pressure testing will check the cyl bores, but will not check the decks, where a lot of overheating cracks occur.

So, there are many good options for crack checking. Interesting enough, most of the time an experienced eye can find a crack right off...and the testing is just to confirm it is a crack rather than just a surface blemish.

John