When is it the right time to do a top end build??

[BillyW124]

..4Pot so nothing too major i shouldnt think.

My car has hit a 100k this week, and being fwd thinking ive been gathering info on the best ways to maintain and keep her sweet.

But really, what sort of milage is a good time to carry out this type of work?

My compression as it stands is good on all four so i dont think anything needs doing just yet.

Do i just go on the signs of good compression and assume everything is ok or are there any other indicators that would tell its time?

..and exactly what is consisted of a top end build:

so far ive read on :

• skimming the head
• re-bore
• and changing the piston rings.

Is there anything else that is involved on a top end build and to explain essentialy why the above is carried out?

Thanks chapps.

 

[Sp!ke]

I'd wait until your head gasket fails - should be sometime in the next 20k.

I wouldnt bother with piston rings and rebore unless thay need it (unlikely) but it would be worth getting the head sent off for a refurb with new valve seats and a skim at the same time as doing the headgasket as its cheap enough to get done.

 

[BillyW124]

I'd wait until your head gasket fails - should be sometime in the next 20k.

I wouldnt bother with piston rings and rebore unless thay need it (unlikely) but it would be worth getting the head sent off for a refurb with new valve seats and a skim at the same time as doing the headgasket as its cheap enough to get done.

how would you tell if the piston rings need changing and a rebore need doing?

 

[MicB]

If it is not broken do not fix it. Head gasket, or worse could go tomorrow, or more likely not for many years and/or many tens of thousands of miles yet.

Mic

 

[219]

how would you tell if the piston rings need changing and a rebore need doing?

Excessive oil consumption / blue smoke .

 

[kth286]

my 320 coupe has done 177,000+ and I'm not at all concerned.

I'm all for preventative maintenance, but in my view you're taking it too far.

it was estimated (somewhere) that 30% of all car problems are owner instigated. (meddling where there is no need).

Leave well alone.

 

[wemorgan]

Noisy tappets is another sign of top-end wear.

Forum member Will recently had his 190 16v top-end reconditioned. Have a search through the threads he's started for further information.

 

[BillyW124]

If it is not broken do not fix it. Head gasket, or worse could go tomorrow, or more likely not for many years and/or many tens of thousands of miles yet.

Mic

my 320 coupe has done 177,000+ and I'm not at all concerned.

I'm all for preventative maintenance, but in my view you're taking it too far.

it was estimated (somewhere) that 30% of all car problems are owner instigated. (meddling where there is no need).

Leave well alone.

yes i agree if its not borke dont fix it! im just trying to gather opinions on a topic like this.

i would obviously do it when i can see a change in engine running etc.

The thing is i have a snapped exit manifold bolt far right at the bottom (where they usually go) which is causing a slight blow. The thing is if those threads are F%^Cd then its going to have to be a head off job anyway.

The bolt that has actually snapped i can see enough of the thread, but who knows when doing the job that when replacing the rest of the bolts and threads they all aint going to be !

if its a head off job then what route do i go down then, obviously changing the gasket for starters.

..at least it will give me an indication of condition under there i guess..

 

[GP801]

Before Olly did the head gasket on ours the tappets were a bit noisy on start up. He said the tappets were fine and after doing the gasket the noise vanished. Can only presume the oil was being lost throught the leak.

 

[Sp!ke]

how would you tell if the piston rings need changing and a rebore need doing?

You would need to perform a leakdown test to get a reasonably accurate measure of this.

 

[BillyW124]

Before Olly did the head gasket on ours the tappets were a bit noisy on start up. He said the tappets were fine and after doing the gasket the noise vanished. Can only presume the oil was being lost throught the leak.

humm interesting, the gasket plays a very important role. would anybody know if there has been any modifications on 124 head gaskets in the sense of making them better in anyway as to when they were fitted from factory?

IIRC the follwing need to be checked for leaks: FRONT CRANK OIL GASKET, FRONT UPPER TIMING COVER GASKET..

 

[BillyW124]

..im not mad honest!

 

[GP801]

Me thinks you worry too much. It could be years before it needs doing. If it aint broke dont fix it. Just keen an eye on things and you will be fine.

 

[trapperjohn]

..im not mad honest!

I can't certify that one way or the other But we have met twice and you are perfectly sane to me. OCD but perfectly sane.

Let the car work for you, not you work for the car. It is in lovely condition, runs lovely, looks lovely. One of the best if not THE best 220 Coupe I have seen.

Relax and breath.

 

[Sp!ke]

IIRC the follwing need to be checked for leaks: FRONT CRANK OIL GASKET, FRONT UPPER TIMING COVER GASKET..

I wouldnt particularly worry about either of these unless you are leaving puddles of oil each time you park.

 

[Smiley]

..im not mad honest!

you have too much time to think

my car is on 240k and seems to be running fine it stumbles and stutters a bit when cold and then soon clears - been like that for the last 90k miles and havent touched it.

find something else to worry about

 

[BillyW124]

whoa! u lot must think I am mad!!! im actually laughing as i write this!

Thanks for the re-assurance chapps, just wanted to sort of make sure i dont have to start messing around just yet. More improtantly wanted to nail it on the head if its a nessasary route to go down when it reaches a high milage. Just gives me scope for the future (incase).

By the looks of it, sounds like this task is way off, good job and all.

general feeling then is..


IF IT AINT BROKE DONT FIX IT!

Absolutely!

 

[BillyW124]

I can't certify that one way or the other But we have met twice and you are perfectly sane to me. OCD but perfectly sane.

Let the car work for you, not you work for the car. It is in lovely condition, runs lovely, looks lovely. One of the best if not THE best 220 Coupe I have seen.

Relax and breath.

cheers John, my mates and my missus knows, i defo have OCD with it. i know myself, hence these type of posts!

very well put aswell, let the car work for me.

..its a bit far from the best, but once i've finished with it, would say 3/4 there then ill be satisfied.

off to see Clive tomo in peterbrough so we can get cracking on bits that need doing behind the scenes.

Get it all tackled before winter sets in again.

 

[BillyW124]

I wouldnt particularly worry about either of these unless you are leaving puddles of oil each time you park.

As Trapper put it..."you see that tray under there young man... its BONE DRY, if it were wet i would be worried"! LOL

 

[bolide]

I can think of at least forty things to do on a W124 before any engine work could even be considered sensible. In my experience it's one of the last things on the car to give trouble. Some people experience a blown CHG on a W124 - but lots don't

Nick Froome
the independent Mercedes Estate specialists