[judgecolt6]

I have 1999 range rover 4.6 hse. Has been pressurizing the coolant system, I'm told a sleeve in the block is slipping/leaking sporadically. What to do? I love the rig, and am just getting comfortable beating it up off-road....now this. $6K to rebuild? Anybody have any suggestions?
Thanks!

 

[Nico3687]

$6,000 to rebuild? Never heard of that. I'm pretty sure you can have one of Martin's better than new Rover V8s for less than that, if memory serves me right.

 

[leftlanetruckin]

Thanks for the kind words.
$4500 for one of my motors, but how do you KNOW its slipped a sleeve? That is the biggest myth out there. Head gasket(s) maybe, a slipped liner, doubtful.

Martin

 

[Guest]

what is the history shortly before it started pressurising the cooling system? not by any chance a repair where the coolant has been drained?

air in the system gives symptoms very much likewise to those of a blown headgasket or a slipped liner.

 

[judgecolt6]

Thanks for the info....a few details: I replaced the radiator last year, as I fell victim to the little engineeing joke of breaking that fragile little plastic hose nipple placed on the top of the radiator.
Have had to add coolant frequently, as it blows it out when the pressure builds. The fill looks higher than everything else, if I fill it when warm (tstat open) will it still hold air? It doesn't pressurize all the time. Does not seem to be any coolant in the oil. 120K miles.

I read a bit about the sleeves slipping, but I don't know how to tell for sure. Any thoughts?

I'm going to retrieve it from the shop today and keep it at home until I figure out what to do.

Thanks!

 

[spikemd]

You need to do a lot more diagnostics before determining its a slipped liner. Check the coolant for gases with a simple head gasket coolant test you can buy online or possibly rent. That will let you know it is either head gasket or remotely a slipped liner. Pressure test your system and be sure there are no leaks.

So are you saying the pressurized system is forcing the coolant out the expansion tank? The system generates quite a bit of pressure under normal operation.

A head gasket takes some time to do, but you can knock it out in a weekend.

 

[judgecolt6]

Bought the test fluid. Pulled the overflow tube from the expansion tank straight up, and ran tygon tube from it to a soda bottle with some of the fluid in it, with a loop so no coolant went into the test fluid. Ran the motor for twenty minutes without the expansion cap in (so the overflow tube hole would be exposed for free gas flow). Held some plastic wrap on the fill with the bottom of a beer. Worked, but kinda annoying as the beer was still half full and I couldn't drink it without ruining the test, and it was heating up...

. Anyway, the fluid stayed blue for about 15 minutes, but then slowly, but surely, turned green. A condition, I'm told, indicating a small exhaust to coolant leak. Guess I need to ask Martin "how much for a set of heads?" Oddly, though, heater turned on full blast ran cold the whole time.

 

[leftlanetruckin]

If the heater blew cold, it's normal for that when the cap is off. It needs pressure to get to the heater core.
I can build heads no problem, and get all gaskets and ARP head studs etc. I wont be THE cheapest though, as I don't buy gaskets from Ebay and the likes. Not worth the savings when considering the risk involved.
Get the heads off though, and see what the gasket looks like. If it looks good, then it's time to go digging and look deeper into the engine.

Martin

 

[NorCal RR]

I don't think your test is very conclusive. That looks like the bottle of liquid from the NAPA kit that tests for combustion gas in your radiator steam. But you didn't follow the test procedure at all. You are supposed to start with a warm engine and test for 1 minute. If it took 15 to slightly discolor it was probably from steam condensation in the test liquid. I would run it again using the kits cannister and bulb following the instructions. Your description of "pressurizing the coolant" sounds like what normally happens as the temperature increases on a sound engine. Sounds like you been slowly torturing the engine running it without a sealed system.

 

[leftlanetruckin]

I totally agree in running the test, per instructions, to determine if there is a major issue or not.
Dont want to spend a weekend and @$5-600 finding out it never had an issue!

Martin

 

[hjames710]

Also remember that a faulty coolant overflow tank cap will cause coolant to boil out. I'd try replacing that first. Only buy a genuine Land Rover one. I bought a cheap one from AutoZone and it wouldn't hold pressure whatsoever.

 

[judgecolt6]

OK, you guys are right, I didn't buy the kit per se, just the fluid, but it did bubble through the overflow tube the whole time (20 minutes). I thought if it was a for sure substantial leak it would show up. I want to be optimistic about it, but the way the system keeps pressurizing and blowing coolant/hoses, at 120k miles, I don't know. When I take the cap off hot it "boils" quite a bit. Will play with it some more, and make sure I don't have some weird coolant blockage/air bubble somewhere. I saw the different burping techniques elsewhere on this site, and while some guys say you shouldn't have to I can attest that sometimes you definitely do (from an '86 classic I had )

If I wasn't busy trying to save my marriage/business and catch a few salmon I'd have had those heads off just because...

Thanks for all of your time.

 

[NorCal RR]

A P38 operates under the same principal of other modern engines. The cap has a built in pressure relief valve which is set to around 15 psi. This allows about 45 degrees higher of a boiling point of the coolant. Under normal operation, the plastic expansion tank allows the liquid to heat up and expand without breaking something. If it gets over the boiling point, pressure is vented by the cap (assuming a hose breaking didn't cause the overheat). If you run it with an open system, you can't build up pressure and you will loose coolant at lower temperatures than you should. For awhile it will be ok until you loose enough to where it can no longer cool. Removing the cap on a warm engine will typically cause pressure to escape, that's why its a dangerous practice. First thing, fix the leaks in the system and replace the cap to insure its functioning ok. The cap will vent pressure if your engine is pressurizing the coolant. Then you can also run a proper test for exhaust gasses.

 

[judgecolt6]

Little update, burped the system until steady stream coming from the radiator hose to the expansion tank, hoses still getting really hard after a few miles, and I can hear coolant sloshing around in the heater system at times when I start and turn. Thinking I have air trapped in the heater coil somehow. Tried elevating the front, but apparently I didn't go high enough. Will look for some stairs to climb. Maybe elevate and fill the heater coil through the firewall pipe? Also, I discovered I had a correct but non-rover radiator cap. Have ordered a new one.

Thanks for any observations...

 

[Gilbertd]

You should not be able to hear water flowing through the heater as any air in the heater should be removed when you start the engine from cold. The thermostat will be closed so all coolant flow will be through the heater and will push any air out. Flow is from the hose coming off the inlet manifold, into the heater stub nearest the centre of the car, return from the stub nearest the RHS of the car with a piped tee'd off to the header tank. Even if you had air trapped in the heater matrix, it should make it's way to the header tank within the first few seconds of running.

 

[judgecolt6]

Thanks Gilbertd. I'm was hearing the slushing when it's warm. Makes me worried its not just a "burp" fix. Anyway, what I did today was put the expansion tank side front wheel up on my stairs, then blew out the radiator bleed hose, reattached it, ran it until the thermostat opened (the coolant level swelled up out of the expansion tank and boiled/bubbled quite a bit along the way, although the temperature was not hot enough to scald, at least not my arm). Pretty positive I put more coolant in after it settled than was pushed out....we'll see what happens now.

 

[judgecolt6]

UPdate: Burped the thing 3 or 4 times, have driven about 200 miles, no overheating, heater won't blow hot air unless I hit the "program" button, can hear coolant sloshing under the dash, system pressurizes pretty good (hard hoses), not sure what's up with the heating system, but does not seem to be a exhaust pressurization, at least not constantly, any ideas?

 

[NorCal RR]

Maybe the heater core is clogged or only allowing partial flow. If you still have your original heater o-rings you might want to do the "Audi core swap" mod anyway as the o-rings are past their life span anyway. I would also check for clogged AC drains or water in your fans leaking in from the cabin filter covers. That could be the sloshing sound.

 

[judgecolt6]

Thanks, I didn't know about those issues. I'll continue to keep an eye on it, and will "burp" it again tomorrow. It really pressurizes the hoses, but soffens up the next morning. Major wonder is why it blows hot when I push "program" and just regular air any other time. Thanks again, Judgecolt6

 

[Kansanbrit]

My experience of a slipping liner is overheating, lots of air and a big rattle/clackerty clack like a major loose tappet when the engine gets to normal temp.