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Tim Mohr
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LR Discovery 2: LR D2 2001 knock in engine, idles rough like

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LR D2 2001 knock in engine, idles rough like it will stall. Recent head gasket change. "Check Engine Soon" light flashing. What is most likely problem
Hi, my name is XXXXX XXXXX is most likely caused by bad rod and main bearings in the engine, when the headgaskets blow, it usually gets xoolant into the engine oil, and it damages the bearings, was there coolant in the oil when the headgaskets blew?
Customer: replied 3 years ago.

I had head gasket replaced about 4,000 kms (2500 miles) ago. Today there is no coolant in the engine oil.

I understand, but usually the headgasket is not caught rightaway, and the coolant gets in the oil, and it can damage the bearings, and they will go out soon after the headgasket is replaced, especially if the engine had higher mileage when the gasket went out, how many miles does this have on it?
Customer: replied 3 years ago.

Total is 176,000 km or about 105,000 miles on vehicle. However I replaced engine at approximately 140,000 km or about 85,000 miles. Had head gasket changed because of oil leaks. The replacement engine is a Jag engine.

ok, but a knock is still going to be either rod or main bearings, the only other thing that will caise a knock is the wrist pins on the pistons, if this only has 25k miles on it, then it should still be under warranty from JAG, was this a rebuilt motor or a used one?
Customer: replied 3 years ago.

Used, but not sure as I got it through local mechanic who installed it. I paid $5,000 for engine plus labor.

the first thing to do is to pull the oil pan, and check the rod and ,main bearings, the knock is the biggest concern here, with the pan off, you can remove the cap for the main bearings and the rod bearings and see if they are worn, a visual inspection can usually tell if they are bad, but you can also plastigauge the bearings to see if they are worn, if so, then the bearings will need to be replaced,Tim
Customer: replied 3 years ago.

Can I still drive it? Nearest LR dealer is over 100 miles.

I would not drive it with the knock, If the bearings are bad, you could cause further damage to the crankshaft, and that could real expensive, every time you hear the knock, it is hammering the crankshaft,Tim
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