starting query

[Nik_Codling]

Last post for a while, i promise!

My '89 300CE often rattles the top end when i start it from cold - it stops once the oil pressure gets up to normal (within a few seconds). Should I worry about this? It's very often only for a second or so, and doesn't always happen.

Also, when starting from the cold, the engine can take quite a while to catch - often three or four seconds, and yet it starts instantly when it's warm. It reminds me of when i blew the head gasket on a Mini and it was hard to start because coolant was leaking in to the engine..... Any ideas?

cheers,

Nik

 

[kid-jensen]

Starting Problems/Rattling

Nik,

I suspect these problems are related.

The oil is draining away from the hydraulic tappets overnight, and affecting compression untill they pump back up with oil.

to diagnose this.......when it's cold, disable the spark and turn over the engine until the oil pressure comes up. Then quickly re-connect the spark and see if it starts straight away.

I guess you need a solution that doesn't involve a top-end rebuild............Try changing the oil for something synthetic and thin to see if it improves things. This should punp-up much faster.

If not, live with it and start saving.........

 

[Nik_Codling]

starting problems/rattling

Thanks Paul,

That makes complete sense.

Can you recommend an oil for me please?

Can't believe the top end needs rebuidling at only 111,000 miles???

cheers,

Nik

 

[kid-jensen]

OIL

The time for a rebuild generally depends on the oil-change history and driving style over the last few years. I really wouldn't loose any sleep over it until you can't hear the stereo.........

I've always liked Mobil 1 but check which viscosity is recommended by the handbook.

 

[Nik_Codling]

Oil

Thanks Paul.

Maybe I should stop entrusting all this stuff to my (non MB) dealer, just for the sake of a stamp in the book..... Wouldn't surprise me if they've not been using the right grade of oil.

I have to wonder how much value there is to FSH, when I'll probably have the car for at least another couple of years, by which time it'll be 15 years old and well in excess of 150k on the clock...It irritates me paying someone else to do the work that I could eaily do myself, purely for the history. Although i must confess it's nice to let someone else do it.

I've had the car since 91k and have had the oil changed every 6k. It generally gets a quiet life, with occassional trips to 6000rpm when over-taking.... In between oil changes it barely requires topping up, maybe half a litre, so it would seem to be a reasonable shape.

Anyway, thank you for your advice Paul, it's much appreciated.

Nik

 

[Nik_Codling]

rattly start-up

Interestingly, the car didn't do the rattly thing this morning, and started perfectly - I guess with the cold weather the oil is staying put a bit better.

 

[sunil sood]

nik,

Mine used to rattle on startup for 2-3 seconds while the oil was getting to the top end. i had put 15w/40 mineral based oil at the oil change.

Then, i switched to a 10w/40 semi-synthetic oil and the top end rattle has stopped as this is a thinner oil. Mine's a 190e-1.8 litre with 112,000 miles.

I use oil from german and swedish- made by QUANTUM.

It also takes 3 or 4 seconds to startup when cold and starts instantly when warm-i do not think this is abnormal with a car that has 112k on the clock.

:lol:

 

[Nik_Codling]

starting

Hi Sunil,

Thanks for your message. I'll try a thinner semi-synthetic, that sounds like the best bet.

Funnily enough, it hasn't done it the last two mornings - started perfectly!

cheers,

Nik