general info on big end bearings needed

[Ricky]

Well after some advice on another forum from ash23, I since realised that my newly built hdi rod xud may have spun a shell or two because I put them in the wrong way, been told that the little cut out on the rod needs to be at the back of the piston, not the front like the standard bearings on standard rods.

Since I have been trying to research all I can into big end bearings, what they do, how to fit them.properly etc etc. And there is a lot of varying information about that is confusing me.. I don't understand how the HDI bearings work, a lot that I have seen have a small hole in them, but these don't do they? Are the little tabs on the edges there to circulate oil? And therefore me putting them in backwards starved them of oil?

I know this write up will probably make no sense! I basically want someone to quickly explain how to fit them properly firstly. And also how they work..

Sorry for the long story! And thanks in advance to anyone who can help. I want to build up another engine but don't want to get it wrong again

[daddyfixit]

there should be cut outs that locate the shell into the rod and the big end cap. the holes in the shells are for oil to pass through---you will find tiny holes in the rod---this takes oil up through the rods to the little ends. so there fore when the shell is in place on the rod, you should be able to see the oil feed hole through the hole on the shell ( this hole that feeds the small ends via the rod).

[Dum-Dum]

The bearings have a small tab that locates them in their relevant positions, they almost feel like they clip into position when you get it right.

And yes they should have a small hole for oil for lubrication and this should line up with a small hole on whatever they sit on.

Theres also small holes in the crank and all the way up the rods to the small end bearing to keep them lubricated.

Ive added some pics so I hope you can see what im talking about.

   
   
   
   
   

[Ricky]

Ok cheers guys. So how would putting them in with the tabs at the front and not the back affect them? Will the oil holes not line up or something?

[Dum-Dum]

Ok cheers guys. So how would putting them in with the tabs at the front and not the back affect them? Will the oil holes not line up or something?

If you have to ask after looking at my pictures you shouldn't be building engines lol

If you put them in wrong then the oil ways wont line up but also the bit with the tab on wont be located and will either cut a nice gouge in your crank or pickup and spin or maybe both, either way itll f*ck your shiny new engine.

[darrenjlobb]

im not really sure how you could have put them in the wrong way...you would struggle to get the bearing cap on flush.....And for the referance, these dont have oil way up the rod to the little end....its just a drip fed lube on it from the bore squirter.

[Ricky]

The locating tabs were in the cut outs, I managed to work that out, but apparantly on hdi rods the cut outs should have been at the back in relation to the piston instead of at the front like standard, or something like that.

[Dum-Dum]

Ahhh, gotcha, yes there is a correct way for the rods to go in but ive completely forgotten how you tell, i remember that there is though cos i got half way through fitting pistons to rods and had to remove them and spin the rods 180 degrees.

[Ricky]

Yeah sorry only quickly scanned your pics. Think it may have spun a shell or two because they were in the wrong way. Cheers for the info though guys

[darrenjlobb]

What makes you think you have spun a shell? Lost oil pressure / bottom end knocking?

Rod goes in one way to do with the direction of spin on the crank, but having tabs both on one side not sure that it matters that much even if it is in the wrong way....

[Ben]

I had to take my pistons back out and turn some of the rods round the other day after looking in the haynes. The shell cut out side of the rods should be at the front of the engine, same side as the pattern on the piston..

[Ricky]

I had to take my pistons back out and turn some of the rods round the other day after looking in the haynes. The shell cut out side of the rods should be at the front of the engine, same side as the pattern on the piston..

That's on standard rods, apparently hdi rods need to be the other way round.

I think its spun a shell because it started tapping when I was driving along, slowed down to pull into a layby and it turned into a bad knock, by the time I had stopped it would barely even tick over. And there was plenty of smoke coming from the filler tube to..

[Ben]

Oh :/ Mine may have to come out again then, they are also HDI rods. Well it didn't say anything else in the haynes, don't really know how else to find out which way they go? Where did you find that they should go towards the back?

[Ricky]

Ash23 told me on another forum, hopefully he will see this thread.

[Dum-Dum]

Right having looked through all my pictured of my HDi engine build I can tell you that the rods went in with the writing towards the back of the engine and the plain side towards the front and this means that the cutouts for the tabs on the bearings were at the front of the engine.

Hope that helps.

[Ricky]

Confused now! Will have to ask ash where he found out his info.

[Ben]

Don't have a plain side on my rods. One side has writing and the other the bore number of the rod. Not going to go outside to check at the mo because its cold but I'm pretty sure the cut out side was also the writing side..

[CJ_Derv]

Well heres one for ya no one knows what my HDi rods are from lol

[Ben]

Ha yeah I saw that thread. Why don't you ring peugeot and give them the part number which is on them?

[CJ_Derv]

Just not had chance, pretty sure they came out of a shitroen tbh so will ring them both my mate works at local peugeot just alwaus forget to ask lol

[Dum-Dum]

From memory none of the numbers on my rods matched the peugeot part number on the box they came in (direct from peugeot)

[Ricky]

This is what came out.. rod 2 from gearbox. only took off two big ends, the other rod bearings were pretty scratched so guessing they would end up the same if they had the chance.

[Niall]

uh oh!

[Dum-Dum]

Thats no lube.

[darrenjlobb]

Oh dear, thats gunna have ruined the crank to

[Ricky]

Yeah the crank is ruined Getting a new engine next week. Would I have lost oil pressure from this then? Hope the head and turbo are ok.