Timing Chain Replacement Question '85 500sec (? Talbir ?)

[Hal Fisher]

I read in the Chilton that its a simple operation of cutting the old chain, connecting one endlink to the new chain, then turning the engine to run the new one in. Is it really that simple? Would that alone end worries that it will break and ruin the engine?

Hal

 

[landover]

YES mate its that easy .How many miles has your car done .
What type of car is it.

 

[Hal Fisher]

Great! Its the 5.0L V8 ('85, 500sec). Should the tensioner and pulleys also be changed at the same time? Anything else as well?

Hal

 

[talbir]

The most important part to change is the tensioner....when engines are destroyed it's usually down to the tensioner failing rather than the timing chain itself.

Timing chains on the 420, 500 and 560's ought to be changed around the 100k mark. On the 380 SEC's, which had singular chains (as opposed to the duplex chains on the other V8's), they should be changed around 60k miles.

 

[teky]

i wish i could agree but nothing is that simple :idea: , they are duplex both the 500 and 560 and setup is the same just ensure you have the setup data so you can line the cams and crank up

 

[Hal Fisher]

Talbit, do you mean the tensioner spring assy? Can the tension rail be replaced fairly easy at the same time or does the front engine cover have to be taken off to get to that?

Hal

 

[Hal Fisher]

Anyone know if its necessary to replace all the rails when replacing the chain (engine has 170,000 on it)?

Hal

 

[teky]

the chain will outlast the car in most cases, only time it fails is because of lost oil and filter changes, to change the chain guide the front has to come off but i bet a new tentioner is all you need "simplest and cheapest way first" then you havent lost any money because you should change that first anyway, follow the instruction ( immerese the tentioner in oil and purge it by pressing it in ) this fills the tentioner with oil so you dont jump a tooth do it a few times to ensure its full of oil, change the oil and filter at the same time

 

[Hal Fisher]

Don't know if I need to replace it now really. Not making any noise or anything. Does it give any warning or is it all pretty much up to chance when it goes out?

Also, what are the dangers of filter changes???

Hal

 

[teky]

oil/filter changes make the difference :wink: , there is no time limit on changing the chain

 

[teky]

oil filter change "dangerous" use the right tool :idea:

 

[Hal Fisher]

Now you really make me ask the outright question. What right tool are you talking about? I will use all the correct size sockets on the pan and the filter nuts. Is there a secret technique to something?

Hal

 

[talbir]

Hal,

All you need to change is the tensioner and chain.

There IS a limit to the life of the timing chain and ti is generally accepted that it is very good preventative maintenance to change the timing chain plus tensioner after 100,000 miles. Accepted that this is not formally written in any MB owner's manual, but it is common knowledge in enthusiast circles. It's also worth checking the oil pump and oil lines.

As for the oil filter changes, there is no special tool for the M116 and M117 V8 engines on the SEC - it's simply a 13mm socket required to loosen and remove the bolt, then lift the lid on the oil filter housing and replace the filter cartridge.

There is a tool to remove the oil filter on the M103, M104 etc straight-six engines, but they are different oil filters altogether.

Again, prevention is the best route...when performing oil changes, use a litre of engine flush liquid (1/2 litre), which you pour into the engine, start and run the engine for 30minutes, then drain the oil. Then use engine flush oil, 5 litres, again start and run engine for 10 minutes at higher idle and then drain out this oil too. Finally, change oil filter and then fill with new oil. Obviously, use a very good make of oil with the correct viscosity. It's the most important component in the engine.

Routinely changing the oil regularly and correctly is the best fom of prevention...but it's worthwhile removing those valve covers once in a while to see what the state of things is underneath.

 

[teky]

the correct tools required are cam locking tool/flywheel locking tool/cam lining tool, i will put the data up for you :wink:

 

[teky]

http://www.benzworld.org/publications/pub.asp?id=296

 

[landover]

This is away of the subject .If your car is running nice an quite with no noises best to leave it

No special tools are needed to change your oil and filter..

You can feed a new chain round the drivegear as long as you keep the tension on top pully at all times