Hello all, vehicle is 2002 with 112,000 miles. The head gaskets were last replaced in February of 2012 roughly 16,500 miles ago along with new coil packs and water pump. The heads were checked then and I was told that they didn't need any machining. I was also told the rest of the engine looked good except for the obvious head gaskets failure

Current symptoms are loss of coolant through over pressurization of the overflow tank (I assume exhaust gases are getting into the coolant). Pressure test of the cooling system failed (45 minutes, 4 psi lost during this time) and there is no external coolant leak observed. Smell of coolant at the exhaust tailpipe and I also have a misfire at cylinder #4, code P0304. When I recently changed the oil, the oil was not milky colored but it did seem thinner than usual. Expansion tank and cap have recently been replaced. The engine did overheat one time and was immediately shut off, towed and parked. Also mechanic looked the truck over and diagnosed it with head gasket failure.

Assuming the previous head gaskets were completed correctly, what would cause the head gaskets to fail prematurely so quickly? I plan on doing the head gaskets myself this time around and was wondering what I should look for as I dig into the engine in the next couple weekends. I intend to get the heads checked at a machine shop.

Also where are people getting head gasket kit and studs from these days?

Thanks for the help

 

I got my studs at lucky8. They were the cheapest I could find at the time.

Lucky8 Llc. - Take the road less traveled...

 

I cant say much here but regarding those ARB studs as linked above, the come highly recommened in the Land Rover realm and most people Ive known say you should replace your old bolts with this specific ARB stud kit so your in good shape if you get them. If they also turn out to be cheaper than other kits than just be happy

Regarding the engine, I would get 2 different shops to look at the engine. Always good to get a second or third opinion before you start sinking money into a project, especially with this engine. Try to have a different shop inspect the work done by whoever did your heads the first time. Its very possible that they did NOT do the job correctly. You never know. Also how is your radiator doing?

Also a rule of thumb for anyone with a Land Rover Discovery 2 model is to invest in a more efficient thermostat. The reason being that this specific one will actually keep your engine temps cooler than the one that came fitted from factory. The stat you are probably running is a genuine petrol version and its not very accurate plus it waits to long to open up which will NOT help a hot engine. The TD5 version thermostat is also a genuine part but it was fitted to Diesel Discoveries. Most all sensiors members on here will stand behind this part and you can order it here for $80 give or take after shipping: THERMOSTAT ASSY DII & FREELANDER 180 DEGREES FAHRENHEIT, PEL500110, RNQ028 - Rovers North - Classic Land Rover Parts

Regarding finding parts for your Rover, and specifically head gasket kits you can find them at Rovers North and Atlantic British. Lucky 8 sells the ARB bolt kit you will need though.

Land Rover Parts & Rover Accessories From Atlantic British | Discovery, Range Rover, LR3, LR2, Defender, Freelander and Land Rover Series Parts & Accessories

Land Rover Series, Defender, Discovery, Range Rover, LR2, LR3 & Accessory Lines - Rovers North - Classic Land Rover Parts

Lucky8 LLC

The above links will have most all the parts you will ever need for your Disco and the prices are considerably lower than anything at the dealership. Good luck

 

Having recently done my head gaskets and having had the same symptoms that is certainly what it sounds like to me. I got a Reinz kit from eBay and head bolts... I can't remember where. Advance Auto has a setup for testing tour coolant for hydrocarbons but I would say you are past that.

Since you clearly had a problem before replacing the head gasket I would look closely at those heads. Mine never overheated (it was just leaking) and the heads had to be shaved.

It seems odd to me that you only have a misfire in one cylinder, but if you are sure you are losing coolant then you are.

I am stumbling a bit because I continued to have problems post HG and learned it was my catalytic converters, some self inflicted wiring problems, and MAF (causing misfires). But I couldn't detect any coolant loss.

Condolences. 16500 miles is absurdly short after such an expense.

I suspect the heads weren't flat or the bolts weren't torqued properly.

 

Having recently done my head gaskets and having had the same symptoms that is certainly what it sounds like to me. I got a Reinz kit from eBay and head bolts... I can't remember where. Advance Auto has a setup for testing tour coolant for hydrocarbons but I would say you are past that.

Since you clearly had a problem before replacing the head gasket I would look closely at those heads. Mine never overheated (it was just leaking) and the heads had to be shaved.

It seems odd to me that you only have a misfire in one cylinder, but if you are sure you are losing coolant then you are.

I am stumbling a bit because I continued to have problems post HG and learned it was my catalytic converters, some self inflicted wiring problems, and MAF (causing misfires). But I couldn't detect any coolant loss.

Condolences. 16500 miles is absurdly short after such an expense.

I suspect the heads weren't flat or the bolts weren't torqued properly.

But if it was done properly I think your thermostat is to blame. The 180 degree thermostat was my first replacement part after the HG job.

 

They should have been machined, I would never put a head gasket in without it being machined. It's smart to, and it's assuring its a flat surface so no way of it blowing because of that, the only way it could blow is neglect of the cooling system.

 

Assuming the block is not cracked, my bet is on pulled threads on one or more head bolts.

 

personally, i think your problem stems to whomever told you your heads didn't need to be done. I would have the head decked and run ARP studs.

 

Bingo here lies your problem ....

 

Thanks everyone for the information. I wish I could bring it back to the place that did it the first time to question them further about the heads getting checked, but that was in Maryland and I am now in Maine now. Also for additional information, I replaced my thermostat early last year with a 180F stat from rovers north. When I remove the thermostat I will check it to make the spring begins to open at the correct temperature.


During this head gasket replacement I will definitely get the heads checked and machined as necessary. I also plan to replace the radiator (it is most likely original) with the Nissens radiator from rockauto.


Thanks again