Mercedes-Benz Forum banner

1 - 3 of 3 Posts

·
Registered
1973 220 Gas
Joined
·
3 Posts
Discussion Starter #1
I have a 1973 220 gas. I bought it with a broken timing chain. They had removed the valve cover and oil pan and the broken chain was sitting in the oil pan.

I knew the chain was broke, and have no issues with fixing just about anything.

The problem I have: I have no idea how to feed the chain around the crank cog and get it back up. I cannot see the crank cog from the crankcase

Also, I cannot turn the crank to TDC. For some reason between 5-10 degrees before TDC I cannot turn it. I have removed the spark plugs. What could be stopping it? Would jogging the engine with the starter do damage?

I fear I may end up pulling the engine out to get it in there.

Any suggestions would be greatly appreciated.
 

·
Registered
1965 220S, 1999 Volvo V70 (wagon), 2006 Ford Crown Vic Police Interceptor, 72 350SL 4 Speed
Joined
·
1,830 Posts
It's an interference engine and the engine will not turn while a valve is down. You can undo the valve adjusters so the valves are all seated, then you can turn it.

The engine really needs to come out and mounted on and engine stand. Remove the cyl. head and inspect the valves. Then the block can be flipped upside down and the chain fed in and routed through the gap.

Inspect the sprockets and the tips, if the tips are sharp, they need to be replaced. Replace the guides while you're at it.

Yes, I'm referring to an overhaul. Get a service manual or a Chilton manual.
 

·
Registered
64' 220SEc, 72' 300SEL 6.3, lots of parts
Joined
·
512 Posts
try a coat-hanger or welding rod wire with a 1/4" 90deg hook to grab any part of the chain. OR tape a magnet to the rod.
Appears someone dropped the chain in to the abyss.
I have done it. and fished it out on the 6cyl motors.

Do not use the starter but put a socket on the crank pulley and rock it to free the binding.

Chances are that the engine may have to come out and
on the bright side
this is a good time to "refresh" a 40 year old motor
Valve guide seals, crankshaft seals, rear main, gaskets, the usual stuff.
 
1 - 3 of 3 Posts
Top