Dan,(Snip)... My question is the engine may still have the original engine sealant that is prone to overheating. How would one find out if it's been replaced or not and is Lotus still replacing this on their vehicles ? If not how dangerous is it to have it remain in the car ?
I'm surprised you haven't gotten any replies.
Which engine sealant are you talking about that is prone to overheating?
I'll jump the gun and take a leap.
The cylinder liner sealant... Loctite 572 was changed to Hylomar 3400. If that's your concern, then replacing that would require disassembling the engine, removing the liners, cleaning off all traces of the old sealant, re-sealing and rebuilding. Not a small task.
If that was done under warranty, or through a Lotus dealer or approved shop, then LCU (Lotus Cars, USA) will have a record of it in their computerized service history. Contact LCU, give them the VIN number, and ask:
1) have the cylinder liners ever been re-sealed, or
2) has the engine ever been rebuilt or otherwise dis-assembled.
I doubt very much that Lotus is still re-sealing liners under warranty. In the first place, the warranty on a 1998 has expired. In the second place, the leaking liners wasn't universal or chronic, and not all engines of that time period were rebuilt/ re-sealed. If an engine suffered an internal coolant leak, Lotus fixed it, but they didn't fix what wasn't broken.
The major cause of the problem was found to be the outside contract manufacturer that assembled the V8 failed to follow correct procedures on some small number of early engines... learning curve failure. The Loctite 572 was fine if properly assembled, and once the assembly error was corrected, the problem was a non-issue. But Lotus changed the sealant to Hylomar 3400, and 572 got a bad rap for something that wasn't it's fault.
If a 918 V8 hasn't suffered a liner leak by now, it was probably assembled correctly in the first place, regardless of which sealant was used, and I wouldn't sweat it.