Does This Mi Look Re-built?

[Higgy 0]

Hi,

 

I finally got around to looking at my spare Mi engine. The story goes that the engine was rebuilt, but I do not have any paperwork to prove it. I've not taken many engines apart before, but looking at this one it does look pretty clean inside. Letters on the piston tops are clearly readable through spark plug holes, which would overwise be covered up with carbon?

 

The block etc is nice and clean and the exhaust gasket looks new.

 

I took the sump off and here is the inside:

 

 

The piston caps have letters scratched on them, I cant think this is from the factory (they do have the little marks on them also . .. ... .... ):

 

 

Here is the overall bottom end of the engine. I thought the oil pump casing looked quite clean:

 

 

The head looked much better than the Mi currently in my car :-(

 

 

Bigger images can be found here for greater inspection - Load of pics.

 

Cheers,

 

Higgy.

[Green Machine 3]

Hard to say with out you taking off a big end cap or a mains cap. Usually most engine builders clean the block/head/sump. this hasnt been done but this does not mean its not been rebuilt. the markings on the conrods would lead you to believe it has been apart recently.

 

from how you described it i would say it probibly has, but i would take a look at a few bearins to comfirm

[jonnie205 1]

yes i would say it has, looks clean and also rods are marked. maybe just had bearings and hone etc. You will only ever know for sure if you check bearings etc like green machine says

[saml666 0]

Mine showed similar signs of rebuild, liner honing being one of them but they measured 2 thou oval so I fitted new ones. In the event have replaced pretty much everything. Its worth getting a friendly engine builder to do some proper checks and measurements for you.

 

The state of my liners (which by the way most of my friends who only know as much as me (very little) thought were fine) meant that the rings would have got tight at the bottom and gappy at the top.

 

Additionally we found that the valve seats had been re-cut and that the tops of the valves were too high so could be held open by hydraulic pumping at high revs (excuse me if I'm not 100% accurate, this info is 2nd hand!) - an experienced engien builder spots lots of potential pitfalls...

 

Cheers, Sam

[petert 587]

The head has certainly been apart. Note how the cam caps are still covered in oxidised oil, while the head itself is nice and clean. Stupid twits should have cleaned the caps at the same time!

 

Rods aren't marked with scribers, nor are sump gaskets used in the factory.

[Higgy 0]

Right, I have finally got round to taking a big end off:

 

 

 

Full sized more detailed pictures can be found here:

 

Show me the detail!

 

 

Higgy.

[Pug_101 0]

Right, I have finally got round to taking a big end off:

 

Higgy.

 

 

All looks quite new, but not very good fit. The tiny pitting seen on the bearing is dirt and the scuff marks show a slightly tight fitting bearing or non round bore.

If you've got a torque wrench put the cap back on and measure the engine turnover torque and feel. it should be smooth and quite easy to turn with resistance.

Cheers

[pug309twin40s 1]

Right, I have finally got round to taking a big end off:

 

 

 

Full sized more detailed pictures can be found here:

 

Show me the detail!

Higgy.

 

 

looks like the crank has been reground and bigger bearings fitted and the notch looks on the opposite side on the bearing to where they normally are??.

 

and arent the bearings usually wider then that???

Edited May 21, 2006 by pug309twin40s

[Guest Cartooner]

Oops, somebody did a bad job over here! The grooved bearing has to be on top and the plain one in the bearing cap! And o, my god,..... how on earth can You miss out on the notches. The width of the bearings is ok though, but since they did not get the notches right I'd be very, very careful with this one. Looks like a decent engine but with these mistakes I'd double check everything.

Edited May 21, 2006 by Cartooner

[petert 587]

They can't be XU9 or XU10 rod bearings. Something from another make to fit an undesize pin? You can see the bearing is approx. 2mm narrower than standard. I've never seen an XU9/XU10 rod bearing with a groove. You have two choices. Run the engine as is until blows. It might be a long time! Or, strip it, find a good crank and fit the correct bearings.

Edited May 21, 2006 by petert

[Guest Cartooner]

Oops, did not look well. It's a big end cap. And yes, it should not have a groove and yes it's not wide enough. ( Thought is was a main cap should not drink and post I guess).

Edited May 21, 2006 by Cartooner

[Higgy 0]

OH CR*P

 

The story of the engine was that it was re-built at least 4 years ago and has only run for a very short time.

 

Maybe there was problems getting oversized bearings 4 years ago? and as petert says another manufacturers bearings were used.

 

OR Maybe the crank has been ground so undersized that you can not get the correct bearings?

 

The crank surface does look like it has been machined, and its free from scratches etc. So I guess that a 'competent' machine shop has least carried out this job.

 

So, whats the next plan?

 

Take the crank out, measure the dia and get some correct sized bearings (if not too undersized)?

 

Higgy.

 

Every engine hides a story

[pug309twin40s 1]

i would get the crank measured then get some proper bearings to fit if it hasnt been too far reground.

 

Im sure miles can get hold of thicker bearings then most of places.

[Guest Cartooner]

It looks like they modified the end cap too, to accomodate for the notch of the bearing. So, this makes me think it's a deliberate attempt to find a way to cope with a journal that has been ground too far down. Better search a good crank, I guess.

[Guest ashnicholls]

Its up to you, but i think like petert says run it till it blows is a good idea, it might work just fine, and have no problems, but if you need it 100% sure then measure the crank and start again.

Edited May 22, 2006 by ashnicholls

[Higgy 0]

Right. Just taken off another big end cap. Bearing shell is also non-Peugeot. But in good condition.

 

I measured the crank dia. on 2 big ends. It is 49.5mm. This was done with a digital vernier, so not the most accurate.

 

The diameter measurement makes sence, as 49.5mm is below minimum dia. from Haynes manual. Thus the use of non-Peugeot shells.

 

I took a shell out, stamped on the back was the following:

 

20 Fm -

AB B

66625RA

 

Anyone identify this?

 

 

Also there is an oil groove on both sides of the shell.

 

Detailed crank view:

 

 

My options now are; to run how it is, or buy (if available) 0.5mm oversized shells.

 

Higgy.

[Higgy 0]

Ok, I've been searching the marks stamped on the bearing shell.

 

And I think this is the answer:

 

Fm = Federal Mogul

 

B-66625RA = Alfa Romeo 145!!!! 1350cc engine.

 

Does anyone know about using Alfa Romeo bearing shells?

 

I searched the forum, and one member was using BMW M3 bearing shells.

 

Higgy.

[pug309twin40s 1]

i would run it as it is.

 

there still seems to look a few marks on the crank.

 

the bearing cap has been machined so dont think proper bearings will fit anymore.

[B1ack_Mi16 67]

I searched the forum, and one member was using BMW M3 bearing shells.

 

That's probably me, but that's not with Peugeot rods, it's with BMW M3 spec custom rods so the bearings won't fit at all in the Peugeot rod...

[Anthony 1,003]

I'd run it as is tbh.

 

It's either going to fail in very short order (like a few hundred miles) if there's something fundementally wrong or it'll probably outlast the rest of the car, oilsurge etc permitting.