Hello everybody. I know this is dumb question, does any one heared or ever did re-torqueing a head bolt to stop a minor leak (coolant) between the head & block? The leak is not going anywhere, it's sip-ping (right word-term?)outside between the block & head.Please respond, any suggestion, opinnion whatever it is will be appreciated. You will be helping us or me to settle a big discussion-argument about this. Thank you very much and happy wrenching.

I am assuming - because you haven't indicated - That the engine is a M103 or M104.
In which case it is probably the head gasket - and if so - will eventually require replacement.

You need to post year & model.
Most MB's have used torque to yield (stretch) bolts since the early 80's except the V8's

They NEVER should be "re-torqued"!

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Sorry guys, it's a 1990 420 sel/105K miles. Let's see if I understand (english is my second language) what you trying to tell me. No re-toque on strech bolt, if so, can I replace the one closser to the leak? Thank you very much & happy wrenching.

That is NOT a torque to yield type of bolt, so YES you can back each one off & re-torque w/o issues.

Most common leak is at the left rear of the engine.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

M.B.Doc, thank you very much, but one more question, do I have to do it on all the bolts, or just the one closser to the leak? And again thank you.

You do all the bolts in the order called out in the manual. Do 1 bolt at a time. Break it loose, then torque it per FSM. Repeat on all the bolts.

Hope it works!

Michael