Rebuilt engine - Unsure about compression readings

[London-16V]

Hello friends,

I had my engine rebuilt by a specialist in Germany and my compression readings are:

1 = 11.4 bar
3 = 11.4 bar
4 = 11.3 bar
2 = 11.4 bar

What do you guys think? This seems a bit low?

[Nagilum]

I do have values of 12 - 14 bar in mind, but someone else might give more exact values.

Also: You should tell the temperature the engine had. IIRC CR varies between cold and warm engine.

Regards
- Christof

[London-16V]

Readings were taken on a very hot engine. But fuel pump relay was not removed, only lead to ignition coil.

Will this make a big difference?

[phil]

Did you press the clutch an throttle pedals?

[London-16V]

Yes wide open throttle

[Franz Pickel 2006]

Hello,
What have you ?
ECE
Ruf
Kat?

[London-16V]

1990 ECE! No Kat

[Steffen102992]

Zitat von Henger aus längst vergangener Zeit :

"Verdichtungsverhältnis 2,3-16v ECE.....10,5= 14-16 bar Neuwert.....Grenzwert ca. 12,5 bar.

Verdichtungsverhältnis 2,3-16v RÜF und Kat...9,7=12-14 bar Neuwert...Grenzwert ca.10,5 bar.

Verdichtungsverhältnis 2,5-16v und EvoI ..9,7=12-14 bar Neuwert..Grenzwert ca.10,5 bar.

Verdichtungsverhältnis 2,5-16v EvoII..10,5= 14-16 bar Neuwert...Grenzwert ca.12,5 bar.

Zulässige Differenz zwischen den Zylindern max 1,5 bar "
Zitat Ende (sorry krieg das zitieren auf dem Handy nicht gebacken "

So if you have a real ECE, you have a problem, or your compression tester is not working correctly.
Can you compare the measure with another one?

[London-16V]

Unfortunately i do not have another car to compare.

Im really disappointed in this because the engine was rebuilt by a specialist in Germany.

What can i do? Its like a never ending story

[Steffen102992]

I meant, check compression again with another tool.
Maybe the measurements are incorrect because of incorrect tool.

[Nagilum]

As all cylinders are very close/even on the numbers, It's not unlikely, that it's a problem with your tool.
If they'd be badly done, I'd expect a bigger spread between the cylinders. But listen to Steffen, to be sure...

Beside: Do you notice any problems with the engine? Low power or such?

[London-16V]

Yes i feel low power.
I dont drive the car much. But the company that rebuilt the engine said i need to drive it more...In my opinion power in an engine is either there or its not.

[London-16V]

Hello friends,

I found something very unusual...
It looks like someone installed the incorrect trimmer plugs in my car.

Here is the slam panel sticker and plug. You can see the plug is incorrect.




The EPC lists these as the correct trimmer plugs:

A0145457028

A0155452728

What effect does using the wrong trimmer plugs have? Anyone know?

[Steffen102992]

Yes, your trimmer plug is not correct, I only know those plugs, which you found in EPC.
The numberes were never replaced by another number.
But I don't know, which effect your installed plug causes.
You change the "Kennfeld" /software - Parameters of EZL/Ignition with them. For example if you are in a country with bad fuel quality.

But let me know if you found out, from which car or version your plug.is.

[London-16V]

Hi Steffen the EZL trimmer plug i have in my car is from a 190E 1.8!
Mercedes just told me this.

[Gorilla]

Hi,

This will not alter your CR ratio.

New Rings need to 'bed in' but I doubt you
will see much improvement in the CR ratio.

[you say rebuilt but do not specify the build spec
etc ?]

On a rebuilt engine you should run mineral oil
for the first couple of hundred miles and do lots
of pulls up hills in lower gears etc, be careful
not to use more than 4000 rpm.

Load the engine up so it all beds in without
over revving.

Then flush the oil out and put in the semi or
full synthetic oil, you should never bed any
otto engine in with fully synthetic oil.

The Rings never bed in correctly on the honing
in the bores if using fully synthetic oil.

[In some cases the the bores ''glaze'' you will then
suffer bad oil control and will start to see
blue smoke as the oil burns.]

Then you slowly raise the rev band, do around
1- 1.5k miles and check valve clearances and
change the oil and filter and then drive it like
you stole it.

Not what you want to hear but none of this is
rocket science or top secret.

Regards,

The Gorilla.

[London-16V]

Thank you Gorilla thats super helpful!

Unfortunately it seems that the guy who rebuilt the engine did not use mineral oil but full synth castrol 10w60.
The car has done around 3000km since rebuild.

I dont suppose there is anything i can do now to improve the situation?

[Gorilla]

Hi,

Not really, at 3000 km.

The Rings are bedded in now, so it is what it is.

You could put a camera down a couple of the
Bore's with pistons set to BDC to see what the
Bores are looking like ?

It will more than likely confirm what your now aware of.

Using 10/60 Synthetic Oil for engine 'bed in' with New Rings
and Newly Honed Bore's is not a best practice combination.

If you are going to pull it out again, you could try removing the
plugs, putting a good old saturation/soaking of WD 40 or similar down
each bore, and turn engine over, 5 secs at a time, more WD 40 and so
on, stopping to let the starter cool, all done with the plugs out, to see if it
helps clean the bores up/ bed in and clean etc, as you have nothing to loose.

But at 3000 km its a long shot.

If it does improve, then do not forget to drain/change the oil and change
filtre etc.

Regards,

The Gorilla

[London-16V]

Thankyou Gorilla.

What engine oil would you recommend for day to day running?

Many thanks

[Steffen102992]

I use in normal 16v for daily driving mineral Fuchs Syn MC 10W40.
Never had problems with it.

In my tuned Evo Engine I used first Castrol 10W60 and now Fuchs 10W60.