does anyone know if the 240gl engine, 1988, is an interference engine? i am coming up to the first 50,000 mile interval since i have owned this car and wonder how closely i need to follow the 50,000 mile recommendation. i would like to push it a bit beyond 50,000 before possibly changing water pump and timing belt together, but am i running the risk or ruining the valves in the even the belt breaks?

thanks,

mac

You definitely want to change the timing belt. I would question the need to change the belt tensioner at this time and even the seals unless they leaking and if so what is the condition of the flame trap. The water pump, based on my experience I would replace it. On my 82 240 I just recently had to replace the cam seal and changed the timing belt(4th) and belt tensioner(1st time) at 170K. The front seal and idler seal have yet to be changed as they are not leaking. I have been using synethic oil for the last eight years.

If you are planning to do the work yourself then that's one thing, but if your taking the car to a shop or dealer that's quite another kettle of fish when it comes to dollars.

Mark:

The US spec B230F is a non-interference design. If you're going to have the front of the engine apart doing the timing belt and water pump, do the camshaft, intermediate shaft and crankshaft seals as well as the crank seal housing gasket. Replace the timing belt tensioner, too.

Good advice from Mark about the seals. Seals are cheap and easy to do while your in there. The timing belt is not timed to fail at exactly 50K and you should not worry about extending. I am not proud to say that I have gone over 100K on one. Like anything well engineered there is plenty margin for error. No damage can result if it fails on your engine, it just means your engine stops as with any other failure such as hall sensor, relays, burst rad etc. A broken timing belt is the easiest failure to diagnose, just look into the oil filler cap to see if the cam is turning while trying to start.

Hey David

We are thinking about repl the timing belt on our daughters car. The last timing belt we did on our other 740 was ok. But it was hard aligning the timing mark on the crank. We have never replaced a front crank seal nor an aux seal. Is this hard. We have replaced the front cam seal. It was hard to know how far to push the seal in. Also the spring used for tension kept popping out from the seal. Someone said that dealers use a tool to achieve the correct depth on seal repl.. Have you heard of that tool. So what do you think about the crank and aux seal for first timers. What other gasket is down by the crank. A post mentioned it

Thanx