XU10 bearing shells

[DamirGTI 362]

Anyone bought  std. XU10 main bearings lately with which you've been happy with clearances wise ?

 

 

Just tried a set of "King" , but the clearance ends up a bit on the loose side - between 0.063 and 0.076mm on the plastigauge strip , so on the very limit of the spec 0.069mm seems like .

 

Tried old shells , and those measure up bang on 0.050mm .. i'd use them instead , but a few of them do not look/feel that great , even after a bit of scotch brite polish .

 

Need to check the mains too tomorrow ... as i bought King as well . 

 

Glyco , Mahle , Kolbenschmidt , FAI (?!) and some other weird ones left to try out ...

[petert 637]

I fell for this 18 months ago. I thought I was going nuts. Everything I tried was loose. Here is a copy of a letter I wrote to Spoox, as I was looking for ACL bearings:

 

"I've been having a hell of time with bearings, which I'm going to share with you. I'm not sure how much of an engine builder you are, but you will find this interesting. My saga started with a set of Kolbenschmidt STD bearings that a customer purchased. These are from Germany. They gave a mains clearance of 0.004". I measured this three different ways, as I couldn't believe it. ie dial bore gauge, telescopic bore gauge and plasti-gauge. 

 

I couldn't wait for your ACL order to arrive, so I tracked down locally, a set of 5M1677 STD bearings. Again, 0.004" clearance. Now my head is spinning.

 

The tunnel bore is within tolerance and the crank measures Ø59.985. I have another six cranks and they all measure the same. 

 

I have sets of -0.3mm Glycol bearings so I've installed and measured those up. I will end of with 0.0022" after the crank is ground.

 

What does this mean? They only correlation between the two sets of dud bearings is that they're listed for XUD9 on the package and not XU10J4. This shouldn't make any difference however. In the ACL catalogue, the dimensions are identical."

 

I also purchased at the same time, two sets of King MB5129AM. They also had a clearance of 0.004".

 

https://kingenginebuilders.com/mb5129am?srsltid=AfmBOoqeQBXdSWUtMmUuWxbbyq05HTCy44eaK3A7WxwRbltPi5bfhy8s

 

I still haven't taken this up with ACL, but I will. It's too much of a co-incidence that all can be wrong. I suspect one company is making them and supplying them to the others.

 

Your 0.076mm (0.003") is at least tighter than my 0.004", but still out of spec.

Edited Thursday at 07:03 AM by petert

[DamirGTI 362]

Weird  ..

 

Indeed they do list them up as XU9 shells , mine are also MB5129AM ... Glyco and Mahle are listed as XU10 , at least on the parts catalogue .

 

Mahle are made in China now , last set which i bought for Renault F7R engine where Chinese .

The XU10 ones , 007 HS 18019 000 , are also China from what i can see , unsure about Glyco as there's only bar code which ends up being Germany .

 

KS/Kolbenschmidt parts are the worst nowadays for older engines  , it's class A mickey mouse gear , most anything Rheinmetall group KS/TRW/Pierburg seems to be crap or inconsistent quality wise  (as well as those faulty TRW valve guides which i bought for XU10 head , also Rheinmetall group now) .

 

There's a few variations of the shells , like they always come up in OE specs :

- upper all the same at 1.847mm (black mark)

- and lower can be anything from 1.844mm (blue/yellow) , 1.857mm (black/orange) , 1.866 (green/white) , to 1.877mm (red/brown)

 

The ones which i measured at 0.050mm , on std. ground crank , seems to be black .. i can see black dot on them .

So upper black + lower black/orange seems like .

 

Not sure if Peugeot still sells them .. might try to ask .

 

I've one more block to tear apart and will see if the mains are good/in spec on that one so i can reuse those ..

If not , hmm ... i might try to order both Mahle and Glyco and see what happens with those , in fact i might order both just for s*its and giggles to see how those two measure up compared to King .

 

Mahle std. does seem to come up in little bit different (tighter) measure/grade compared to King , if the catalogue specs are correct , maybe those will do the trick  .

 

 

But yeah , it does seem like common scenario with older cars/engines aka supply/demand , one makes it all just repacked and solid via different brand names ... not an issue at all , if they at least take care to make stuff right fit for the purpose !!

(must be fun rebuilding engines for a living these days  , some which i know gave up recently)

 

Edited Thursday at 08:34 AM by DamirGTI

[petert 637]

I think you mean XUD9 shells.

 

I should also add that I knew I wasn't going mad, as a set of good 2nd hand oem STD shells produced 0.0023" clearance.

[DamirGTI 362]

Indeed ! XUD9 .

 

Taken apart two more engines just now , one 2.0 T and an S16 . 

 

All of them have back grade bearings ! top and bottom and std. ground cranks .

 

Third 2.0 T engine came with 0.30mm oversized shells and ground crank , looks like made from the factory ..

Need to check which paint grade is on those if it helps to anyone .

 

Fourth 2.0 T engine , also black + black .

 

Reading out bearing code markings from the block/crank is really bad on these !! compared to some other makes/models .. Only one 2.0 T engine has clear enough markings all the others are "go figure" ..

 

So seems like black+black is the std shell combination , for the majority of these .

And the same or near close should be expected from the aftermarket ones .

 

I now have a few sets of used black ones , so can pick and choose the best to make one good set for reusing .

But still , will see how much are the Mahle ones and when can i get them , and might order those to try out .. those seem like they might be ok. 

 

Failing that , it'll be new bizzare trend , hoarding used engines for OE bearing shells .. 9.8 out of 10 people telling me im insane on a daily basis piling up the house with used OE parts , i say to defend myself  it's "future investment" 

 

Quite easy to go nuts doing this kind of work nowadays !

Edited Thursday at 10:54 AM by DamirGTI

[DamirGTI 362]

Interestingly , and no idea from where Haynes got those specs , but early engines seem to run quite a bit more clearances ?!(taken from Haynes XM manual) : 

 

[SRDT 248]

On a one-size-fit-all set the lower bearings should be the 1.844mm blue ones, that's what Peugeot tell you to use if you can't check clearance but they also tell you to do this as a last resort as the engine can be noisy.

 

The pre-1993 XU10 internals are a bit special, this engine has wider rods like the XUD11 and the XU10J4TE.

[DamirGTI 362]

Yes ! i found that about blue shells in the OE manual too .. but seems a bit too tight hence the warning about using them .

 

Will be off to pick up Mahle bearings just now , curious to see what happenes with those ..

 

I see what you mean yes , i have one early 2.0 T engine RGY , that one has big robust rods .. but i thought it was turbo petrol and turbo diesel only which had such rods , never taken apart early NA R6A engine .

[DamirGTI 362]

Tried Mahle 007HS1801900 - no good either ! 

 

They do look a little bit different compared to King , but the measurement ends up identical - between 0.063/0.076mm 

 

I give up .. will reuse old OE bearings .

[DamirGTI 362]

Hmm , an set of upper grooved shells looks a bit blue at the back , so seems been running hot .. lower ones look ok. .

 

So what do we think about that , toss the blue coloured away or still good to reuse ? 

Sliding surface looks ok. and clearance also 0.050mm . 

 

 

Edited yesterday at 10:47 AM by DamirGTI

[DamirGTI 362]

Some more pics .. 

 

Shells numbered 1 flywheel side , top ones from 96' engine , lower from 97' both 2.0 T .

 

96' engine was rebuilt some time in the past , it's sleeved ..

97' went poop cause of way too much boost , overheated pretty hard , detonated cracked one piston and head .

 

Edited yesterday at 02:15 PM by DamirGTI

[DamirGTI 362]

There's some difference in bearing code/number for 96' and 97' .

 

Top row different.

Bottom same on all .

 

I wonder if there's difference in the material between the two or it's just different serial number ?!

 

Anyhow , asked at Peugeot but there's none .. can't even be ordered .

 

 

Edited yesterday at 02:17 PM by DamirGTI

[SRDT 248]

XUD9 bearings are 1.842mm with a one-size-fit-all set, those are the same on the 2.0 8v HDI.

On the early 2.0 and 2.2 16v HDI there is a 1.853mm upper and a set of lower at 1.837, 1.845, 1.853, 1.861 or 1.869mm.

I'm not sure how good those diesel bearings are when you rev them way past the diesel rev limit

[DamirGTI 362]

Cheeky bastards ! they're selling all those XU10 bearing shells based on old pre-1993 clearance spec .. 

0.041-0.103mm says so on the specs for Glyco and Mahle !! that's why they end up in the middle while measuring so about 0.063-0.076mm 

 

And some are 20.2mm (Mahle) and others 19.4mm (King) 

OE are 19.4mm

 

And parts catalogue lists them for all the XUD9 and XU10 petrol engines .

 

I wonder if the XU9 petrol bearings would work ?! lower shells at least combine with XU10 upper ..

 

DKZ and RGX :

Edited yesterday at 05:41 PM by DamirGTI

[DamirGTI 362]

2 hours ago, SRDT said:

XUD9 bearings are 1.842mm with a one-size-fit-all set, those are the same on the 2.0 8v HDI.

On the early 2.0 and 2.2 16v HDI there is a 1.853mm upper and a set of lower at 1.837, 1.845, 1.853, 1.861 or 1.869mm.

I'm not sure how good those diesel bearings are when you rev them way past the diesel rev limit

Will have a look .. 

 

But switching years does not seem to make any difference in the size/clearance from the lot of the aftermarket ones , they simply offer one size for the all years .

 

Oh , but might ask at Peugeot if they have some od those .. but guessing chances are bit slim too .

 

Found some weird ones from Mahle 039HS20282000 , which seem to be HDI only but are thicker 1.85/1.856mm about the spec of the black OE lower shells .

No info which material are they made from , but since all the above are also listed for use in both 1.9D and 2.0HDI these should be good as well ?!

Anyhow would need to wait about 7 or even more days to get those ..

 

 

Might be better i simply piss off into the woods shroom hunting , as my brain is cooked 

Edited 22 hours ago by DamirGTI

[DamirGTI 362]

On 9/3/2026 at 9:33 PM, SRDT said:

The pre-1993 XU10 internals are a bit special, this engine has wider rods like the XUD11 and the XU10J4TE.

But wait , this can't be right ! 

 

Conrods yes , they are more beefy on early engine RGY compared to RGX , but we have main bearing clearance issues here not the rod bearings !

 

And it's not the block either , aka housing bore dia. difference .

 

Im building this engine out of an old '92 RGY block which i got sleeved machined etc. , inside there was ground crank with 0.30 oversized mains and 0.50 big end shells , which i choose not to use for that very  reason , and fitted  std. crank from '97 RGX engine in that early '92 block instead .

 

And yet all those bearing shells in the spec for early engines intended for running on 0.041-0 103mm clearances , end up with 0.063-0.076 clearance , but with the shells from the RGX block they tighten up to the 0.050mm ?! 

So where is the difference then , the early crankshaft ? or simply change in the clearances spec cause , no idea guessing thinner oil grades or something like so ..

 

Edited 16 hours ago by DamirGTI

[petert 637]

ACL list the same bearing for XUD and all XU10’s. So I wouldn’t be concerned about that either.

 

All the XU10 cranks I have are identical and I have at least eight here at the moment.

 

I’m just lost on the reason why aftermarket bearings are wrong and need to discuss with ACL.

 

I would give the good oem bearings a scrub with scotchbrite and run them.

Edited 15 hours ago by petert

[DamirGTI 362]

5 hours ago, petert said:

I would give the good oem bearings a scrub with scotchbrite and run them.

Is what l will most likely end up doing , and done so in the past with some other engines .

 

Any idea why some of those upper shells have blue/black discoloration at the back ?

 

That engine has been completely apart some time ago for sleeving , thus not sure if they oiled back sides of the shells , used assembly lube , chemical cleaner or something like so which made them change colour compared to the others .. 

Does not look like classic overheat as the front sides are ok. , block and the crank look ok. too .

And with some scotchbrite play that discoloration goes away/rubs off .

Those are the best , so i'd reuse those or fit just the new upper grooved shells and used lower if that ends up ok. need to check with the plastigauge .

 

Seems like confusion between the two clearance specs and every manufacturer using early spec for some reason . 

 

Those King and Mahle look visually different and measure just slighty different so it's not the case that one makes it all which i thought it would be .

Edited 10 hours ago by DamirGTI

[SRDT 248]

Damir the crankshaft and wider 26mm rods from the early XU10 are very special, they are only fitted on the N/A 8v engines from the 605/XM before 1993.

 

PSA derived both XU10 and XUD11 engines from the XUD7/9 and kept the same bearings on all cast iron blocks. That's why XUD bearings are also listed as XU10, it was true up to 1993.

 

Around 1993 PSA made the 2.0 16v and the 2.0 8v turbo with a new crankshaft and did go back to 24mm rods like on the XUD7/9 and XU5/9. They also updated all the others 2.0 8v before launching the new XU10J2 on the smaller 306/ZX and 405/Xantia.

[DamirGTI 362]

Oh , now i understand ! finaly !! 

 

Did not know that , so early carb/Spi and injection with long aluminium inlet manifold with double barrel TB right ? 

 

I did some work on a few of those in the past , but i never did the whole engine/block .

[SRDT 248]

Jetronic, Motronic, Magneti Marelli multipoint and monopoint, carb : all of them still there at the time switched to the new crank on 01/01/1993.

[Richie-Van-GTi 82 2 Cars]

Opened an undamaged pack of Glyco today to find one with 2 big dings in the edge of it.