The Lotus Cars Community banner

1 - 6 of 6 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter #1
Hi,*

I hope someone can steer me in the right direction. I have 2002 Esprit V8 that let a piston loose through the block a few years back. Engine was rebuilt and all was well, but then it started suddenly overheating. If you leave the car running it will happily sit at temp all day and kick the fans in and out as it should. However when I drive it it will (seemingly randomly) suddenly overheat. I mean the temp gauge pegs to the right in one fast movement. If I don't stop immediately the car will loose all its coolant - So it is not a gauge issue. If I stop the car and wait ten minutes and restart it everything is good again until another random spike. radiator has been inspected, restored, and refitted, Thermostat has been swapped out, Water pump also checked and given OK. I do not know what to try next - Any ideas? Could it be a turbo cooling issue somehow???

At my wits end - Two mechanics familiar with these cars also are stumped.*



Thanks in advance,

Stuart
 

·
Registered
Joined
·
253 Posts
Sounds like maybe during the rebuild something get left in the engine water jacket that's randomly blocking the coolant flow. You might try an aggressive back flush of the engine and see if something comes out with the coolant.
 

·
Registered
Joined
·
3,383 Posts
My guess is a cooling hose collapsing or the radiator somehow getting plugged up. Another possibility is air getting into the system either from a leak or a bad head gasket. It will take some troubleshooting. Start with a pressure test and a combustion gas test. Also worth testing the thermostat just in case it is sticking.
David Teitelbaum
 

·
Registered
Joined
·
81 Posts
Hate to be the bearer of bad news, but that is what I just went through. Mysterious coolant leaks, car wanting to overheat, leaking coolant system. I went through the entire cooling system (not fun) and rebuilt the radiator, replaced all hoses, fixed numerous leaks and it still lost coolant. I finally connected up an overflow to the overflow tank in wheel well. I wanted to find out where the coolant was going. Took it for a drive and once the head gasket started leaking (usually required a bit of boost to leak) it would pressurize the system and the coolant would blow out the overflow. I watched the second overflow fill up and you could see it 'boiling' as the air was pushed out from compression. I confirmed this by doing a compression test and visual inspection of the 'rusty' spark plugs! Oddly enough, I never had coolant mix with the oil so that kind of made me scratch my head. That usually happens when you loose the liner seals.

Not sure when your engine was rebuilt, but a few years back there were some 'inferior' head gasket available. They were not up to the task, but that was what was available at the time. Those were used in my engine and both failed badly.
 

·
Registered
Joined
·
1,231 Posts
My experience is with a 4 cylinder but it was a blown head gasket. I unfortunately got one of the flawed gaskets and it blew out at about 30k miles.
 
1 - 6 of 6 Posts
Top