My 420SEL before valve mishap got about 19MPG regularly, it is slightly underpowered if you compare to the 560SEL rocket ship. The 420 engine is great, the only issue is the timing chain and cams. If it has a loud tick like a bad lifter it most likely has a worn cam. Replace timing chain around 150k-170k miles and replace plastic timing chain guides. Note replacing timing chain is about a 3-4 hour job using two people. Every 70k miles replace brushes in alternator. Other than that it is basically 126 and has the same issues as all the W126s. Note always use anti-seize on spark plugs I have put heil-coils in more than one 117 engine. Never ever remove head bolts, they sell a tool to help you change timing chain that bolts onto head bolts, do not buy it. The aluminum block will strip out when a head bolt is removed, and the only fix is remove head and heli-coil.
Trampas -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Michael Hall Sent: Monday, September 25, 2006 12:42 PM To: Mercedes Discussion List Subject: Re: [MBZ] 126 420SEL My mom's 420SEL had ~230k miles on it when we sold it, up to ~250k now, we never had major trouble with it, although the spare fuel pump relay we took on long trips came in handy on the way back from FL once. Current owner just had to have a soft parts rebuild of the tranny. The whole 126 line was pretty great - in fact I recently read a review for the new 221 chassis S class that praised it for driving like the old 126. I would look for a replacement timing chain and tensioner, though - we've rebuilt quite a few where the chain broke, usually 180+k miles though but I would think age would be a factor. Mike On 9/25/06, Jeff Zedic <[EMAIL PROTECTED]> wrote: > > All I've heard, for what that is worth, is camshafts. > > Here's the EPA fuel economy figures for the 420 > > Fuel Type > > Premium Gasoline > > MPG (city) > > 15 > > MPG (highway) > > 19 > > MPG (combined) > > 17 > > > Here's what they say for the 300 > > Fuel Type > > Premium Gasoline > > MPG (city) > > 16 > > MPG (highway) > > 20 > > MPG (combined) > > 18 > > > Jeff Zedic > Toronto > > _______________________________________ > http://www.okiebenz.com > For new parts see official list sponsor: http://www.buymbparts.com/ > For used parts email [EMAIL PROTECTED] > > To Unsubscribe or change delivery options go to: > http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
