Best Choice Of Mi16 Big End Bearings

[floodys 4 1 Cars]

i've heard from a few people and read a few places about what big end bearings to fit to a mi16, i reckon it will have a 8v crank in it in the end, should i fit XU9J4 mi shells or others? boombang had mentioned XU9D shells, can someone tell me the advantage of these and if worth using??

on a final note, if i go for the XU9D shells, what car would they have been fitted to, i only say because when i ask for them they parts place will ask which car they were in!! i'm guessing it a 306 diesel non-turbo?? lol cheers

[sub205 5]

i've heard from a few people and read a few places about what big end bearings to fit to a mi16, i reckon it will have a 8v crank in it in the end, should i fit XU9J4 mi shells or others? boombang had mentioned XU9D shells, can someone tell me the advantage of these and if worth using??

on a final note, if i go for the XU9D shells, what car would they have been fitted to, i only say because when i ask for them they parts place will ask which car they were in!! i'm guessing it a 306 diesel non-turbo?? lol cheers

the best choice are the xud9te-shells. this engine is f.e. in the 306.

 

the shells are harder material, more durable.

 

since i'm using this shells i had no bearing failures anymore, earlier i had this problem.

 

also really important is good oil pressure. you can use the xu10j2 / xu10j4 oil pump to get a higher pressure, this will also affect the durability positivly.

[sideways danny 0]

good oil pressure, and a quality brand of bearing is most important IMO. ACL, Federal Mogul, AE or a select few others will all be the same shells for anything the same size. Bearings shouldn't touch anyway so heavy-duty is a bit misleading, and if you do get contact, the surface does NOT want to be as hard as possible on the shell.

[Miles 331 1 Cars]

You don;t want harder shell's, You want softer one's, If you want any more info by all means drop me a PM

[Stu 18]

As above, a harder bearing is fine for a steel crank, not so good on a cast one. Id much rather replace a set of shells than a crank every time it needed it..

 

But yeah, provided you check the running clearance beforehand and buy a good quality bearing then it will be fine, i used AE (and nearly always do) on mine.

[sub205 5]

As above, a harder bearing is fine for a steel crank, not so good on a cast one. Id much rather replace a set of shells than a crank every time it needed it..

 

But yeah, provided you check the running clearance beforehand and buy a good quality bearing then it will be fine, i used AE (and nearly always do) on mine.

we have talked a long time with a dipl. ingenieur of glyco germany, and sorted out that the best shells for our engine would be the diesel ones. and: when a bearing fails, the crank should always be regrinded, it will ever have small scratches or rills.

 

higher torque (or higher rpms) squish softer shells, making them thinner. thinner shells will wear very quickly and ruin the crank!

 

both has pros and cons, but i can tell you: after changing to diesel bearings and a better oilpump, noone of us had bearing failures anymore.

[mmt 15]

Interesting tread.

 

I´ve just changed bearings on my Mi 16. The guy in the engine shop did a cataloque(federal Mogul/Glyco) search for diesel bearings. All diesel bearings have slightly bigger dimentions than the mi16 standard ones according to the cataloque.

 

What marque do you use and to what engine?????

 

I race my car and have to change bearings every 10-15 races.

 

Thanks

[floodys 4 1 Cars]

cheers for that, i went to a engine shop and had a browse through the bearing catalogue, we found that the bearing for a petrol 8v and mi16 both 1.9 are the same, the measurements were 59.990 for mains and big ends were 49.984 (bearings that is, not journal size.s) the sizes for the diesel bearings were the same for the big ends but the mains were 59.981, when the lad worked out the difference in the shell's i.e 59.990-59.981 he said it was so small it made no odds!!

So i think, i will go for the derv bearings??? also, the lad said that if i went for the derv bearings he could take more off the journals when grinding as aposed to using the petrol shells because something about derv being 0.50 and the petrol ones being 0.30!! its over my head all these number really, all i want is the car back together!!! lol

[mmt 15]

That´s what "my" machineshop found out too...butthe guy recommended NOT to use the bigger shels although they ara only a little bigger!

 

Religion...I think! :-)

[floodys 4 1 Cars]

just one thing i've noticed on servicebox, XUD9TE is turbo derv and XUD9 non turbo, so which bearing's to go for and difference please!! i.e softer/harder etc!!

[sub205 5]

yes the diesel-bearings are a lil bit smaller, but that does not matter, thats just a bit more space for the oil to fill!

the oil helps very much at this location.

 

also the xud9te (thats what i'm talking about, turbo diesel!) bearings are not as wide as the petrol ones.

 

anyway, personally i can recommend them, but its your engine, everybody has to know what hes doing :-)

[Miles 331 1 Cars]

All I will say is all the engine's I build and I know of a good few other Companies in the UK at least all use the Softer bearing's which I supply from down under

[kyepan 291]

thats just a bit more space for the oil to fill!

the oil helps very much at this location.

 

but won't that reduce the pressure.. as pressure drops as clearance increases.

 

J

[sub205 5]

but won't that reduce the pressure.. as pressure drops as clearance increases.

 

J

 

i do not notice a drop in pressure. we're talking about 1 or 2/100 mm!

[sub205 5]

i do not notice a drop in pressure. we're talking about 1 or 2/100 mm!

the exact rise is 1/100mm!

and yes, a friend of mine with the same bearings has noticed a minimal drop in oil pressure - when idling at 900!

over this rpm the pressure is exactly the same.

this ain't a problem anyway, because diesels idle a bit below the petrol ones and put heavier load on the bearings while idling.

[welshpug 1,661]

no they do not , they idle at the same speed, or should do if set correctly.

[B1ack_Mi16 67]

More clearance will at least give more oil flow past the bearings/journals which will give better cooling of these components.

 

On my race engine the crank was ground a little extra to give a little bit extra clearance between bearings and journal because of this.

 

Edit: Also remember the oil pressure you see in the instrument cluster is only the feed pressure from oil pump, the dynamic running pressure in the oil between journal and bearing is far much higher anyway, probably houndreds of bars, maybe thousands, can't bother to do calcs on it or search it up, but it should not a problem with a little lower feed pressure.

Edited July 9, 2009 by B1ack_Mi16

[floodys 4 1 Cars]

couple of things, what bearing's would i/can i use for the mains? can they be diesel too or do they have to be mi bearings? also, when i bolt the caps and rods together (dry) with the bearings in, i get side movement (with pistons in) also a little up down ovement, is this the gap that the oil will take up?? cheers

[sideways danny 0]

couple of things, what bearing's would i/can i use for the mains? can they be diesel too or do they have to be mi bearings? also, when i bolt the caps and rods together (dry) with the bearings in, i get side movement (with pistons in) also a little up down ovement, is this the gap that the oil will take up?? cheers

 

 

do you have any plastigauge? I'd check the clearance as acurately as possible rather than just by feel

[sub205 5]

do you have any plastigauge? I'd check the clearance as acurately as possible rather than just by feel

sideway movement and a little torsion movement is ok.

 

btw i checked the thickness of the different bearings.

 

RFX 1,843mm

T16 1,837mm

DKZ 1,837mm

XUD9TE (my bearings) 1,838mm

HDI 2.0 1,838mm

DW8 1,830mm

 

so as you can see, the original XU10-Bearings have little lower clearance than the XU9JAZ / 2.0 T16-bearings.

but the diesel-bearings i mentioned have a little less clearance than the stock XU9JAZ/T16 bearings, so why should this be a problem?

Edited July 10, 2009 by sub205