Lars_DK

Hi,

My 1984 Euro S (auto) M28/22 engine was suddenly running very uneven and a test recently shoved that I had no and almost no compression in two cylinders.

A closer look by a 928 mechanic shows that I have two broken piston rings that have scratched the surface. One might be repairable but the other one is probably too deep.

Luckily a fellow 928-owner had a spare M28/21 engine from his old 1986 Euro S that I got for a very reasonable price if I pulled it out myself – he probably and rightfully felt sorry for me :-)

Anyway the “new” engine was running well until about 5 years ago – but is “sweating oil” at the usual places. And now it is out.

My own engine has had a lot of work done the last couple of years:
- All new fuel rails
- Cleaned injectors
- New motor mounts
- New oil tubes
- New distributers
- Renovated & calibrated MAF
- New cables and new spark plugs

…all of which I am going to move to the “new” engine.

While the the “new” engine is out I am going to go do all the other stuff that is normally a pain to do:
- New oil pan seal (it was done 5 years ago, but now it is out)
- Exhaust manifold gaskets (and bolts)
- Rear cam tower gaskets
- Water bridge gaskets (including the always seized bolts – which I just had done on the old engine ☹)
- Water pump & timing belt
- Smog pump delete and change to all electric fans

The ambition is to make it a good runner with all the usual stuff taken care off by a more mechanical minded friend, but without doing a complete teardown down to the bare bones. As much as I like learning about the technical stuff I much prefer driving my 928!

So I would appreciate any suggestions to what I have missed of “must do”-things while the engine is out - and please keep in mind that when it comes to engines I can best be described as an almost complete noob 😊

Regards

Lars


"New" engine is out and ready for some tender care

soontobered84

Lars,

It would be shame to be this close and not replace the head gaskets. I worked on my first 928 ( a ROW 84 5 speed) for 4 years to get it road worthy. I was able to drive it twice and found I had bad head gaskets. If someone had only told me then to go the extra step and replace them while the engine was out.

Lars_DK

Good point. Head gasket added to the list.

Lars

Wisconsin Joe

What kind of shape is the A/C in? IIRC, there's a line that can only be replaced properly when the motor is out.

The clutch master is also far, far easier to do when the motor is out. If yours is original, this would be an opportunity that you shouldn't pass up, even if it's working well (for now).

Lars_DK

My own AC is removed - was too broken when I got it to bother working on. And the donor car flattened the aircon bits when it hit the barrier at high speed :-) Its a good thing the summers are normally quite cool.

My car is an automatic - don't know if that makes any difference when it comes to preventive servicing while the engine is out?

Regards

Lars

Adamant1971

+
-Coolant overflow tank and hoses
-Renew firewall insulation with new heat tape
-Front upper control arms since the bolts are much easier to get at with the motor out
-ABS wire junctions at shock towers as they get super brittle (if equipped)

Lars_DK

Good points - thank you! Did the upper a-arms (928M ones) earlier this year to fit S4 brakes (PO har changed the brakes but not the suspension which made the car impossible to align)

Just prior to the piston ring-problem the ABS warning light was acting up which made the front end brake unevenly (relay & wheel well wires have been changed) so good point to try to chase down further problems while the engine is out.

Regards

Lars

PS; Including a photo of the car just because I miss driving it :-)




Lars