engine noise @3000 rpm

[mikerj]

I wouldn't expect the tappets to be that loose either, when they are operating correctly they need to be clamped in a vice to compress them. Well worth changing them ASAP as it's not unknown for loose tappets to cause the rocker arm to get displaced which can cause significant damage, and tappets are fairly inexpensive anyway. INA parts should be fine.

The number 1 bearing locates the camshaft in the axial plane. I agree with Thrumbleux about the number two bearing cap alignment. The caps never seem to exactly align with the lower part of the bearing in this plane, which is ok but that does look like an unusual amount of misalignment. Are all the bearing caps correctly located according to the numbers on them i.e. number one next to the timing chain, then two, three and four going from right to left?

Since the cam will need to come out to change the tappets you can take a closer look at this whilst the bearing caps are off.

[Thrumbleux]

Are the bearing caps not either numbered, or with direction arrows - or both?

With that amount of lash, commencement of valve lift will be on a part of the cam lobe not designed for it.

[peanut450]

When I replace the camshaft how can I get the tension correct on the chain?
Will this be possible without removing the cam cover ?
Thanks

[mikerj]

The hydraulic chain tensioner sets the correct chain tension automatically. The main difficulty you will encounter is getting the sprocket back onto the end of the camshaft, since you are working against the chain tension. I used a long lever (e.g. strong screwdriver or breaker bar) to push the moving chain guide inwards near the bottom where the chain tensioner is located. This gives enough slack in the chain to mount the sprocket on the cam.

[Thrumbleux]

From memory, I levered the cam sprocket up onto the cam against tensioner pressure.

PDF may have useful info,

[peanut450]

What are the chances of leaving the sprocket on the camshaft ?
Thanks

[Thrumbleux]

What are the chances of leaving the sprocket on the camshaft ?
Thanks

From memory, there isn't enough slack in the chain to remove/refit it over the sprocket.
It is a bit of a PITA remounting the sprocket (with chain) onto the cam but it's not the worst job you will do on a fortwo. It took me longer than it should have as I struggled to decide whether to be a half tooth advanced or retarded ie removed/refitted sprocket several times - so obviously not that difficult. Pretty sure I used 1/2'' drive T-bar to lever it up rotating it slightly on the slack run of the chain. Only fair to mention though that the engine was out of the car while I did the above.

[mikerj]

What are the chances of leaving the sprocket on the camshaft ?
Thanks

Not a chance, you will have to remove the sprocket to get the came out.

[tolsen]

I recall you can lock hydraulic tensioner by removing a certain screw or plug on timing case and insert a pin. Think you need to pull chain tight for tensioner to compress enough for pin to engauge. Will check this further by inspecting mine.

[tolsen]

I recall you can lock hydraulic tensioner by removing a certain screw or plug on timing case and insert a pin. Think you need to pull chain tight for tensioner to compress enough for pin to engauge. Will check this further by inspecting mine.

Just checked on my 450 Cdi and on a spare tensioner.
Plug screw on timing case is slightly above and forward of tensioner so perhaps its intended purpose is to allow tensioner guide to be locked?

[peanut450]

Just checked on my 450 Cdi and on a spare tensioner.
Plug screw on timing case is slightly above and forward of tensioner so perhaps its intended purpose is to allow tensioner guide to be locked?

I hope so.
How would the plug screw be removed?

[tolsen]

I hope so.
How would the plug screw be removed?

Reminds me of a young tasty barmaid that turned screwdriver wrong way when attempting to fit a beer pump badge. After several minutes of unsuccessful screwing one of the locals said to her: You look like the kind of girl that likes to screw!

[peanut450]

Update-Slow progress due to rain.
I have replaced the hydraulic tappets and noticed the cam bearing/caps have got some scoring on them.
IMG_20181013_141147.jpg IMG_20181013_142002.jpg Webp.net-resizeimage (9).jpg
Got the engine back together and started it with much less noise than before but still a louder noise @3000.
Have still got car on stands so have not driven it.