26 replies to this topic

[DeadSquare]

Close together.  The tabs are on the same side of the crank.

[DeadSquare]

For us amateur and infrequent engine assemblers it goes to show that taking a series of pix and labelling items front or back, left or right, 1-4 etc can save us soooooo much anxiety.  I remember when I disassembled, I was convinced my mental pictures would recall easily but now my brain is as rusty as my mini floor panels lol !

 

 

FOR  EVERYONE, not just amateurs.

 

If you are going to remove the crank, at the very least you need a sharp punch (or number punches if you have them).

 

First, make a punch mark on the center web of the inverted block, on the cam shaft side and a mark close to it on the center main bearing cap.

 

Now turn the crank so that it is easy to mark number one con rod (the one nearest the water-pump) and its cap, on the cam side and then mark the block on the cam side with one dot.  Next, make four dots on number four rod and its cap and put four dots on the cam side of the block.

 

Rotate the crank so that two and three can be marked, and mark them as above.

[BaronVonchesto]

 

one other thing, my bigend bearings are the type with the tabs on them. does the bigend cap go on to the conrod such that the two tabs are close together or far apart? 

 

Ouch !

 

I do hope that you know which cap came off which rod.

 

 

oh yea definitely. i never removed more than one cap from a rod at a time. also the crank has been ground and fitted for +10 bearings and the rods have been balanced, so yet another reason why they cant be mixed up 

Edited by BaronVonchesto, 21 June 2019 - 11:24 AM.

[Spider]

one other thing, my bigend bearings are the type with the tabs on them. does the bigend cap go on to the conrod such that the two tabs are close together or far apart? 

 

Both Mains and Big Ends go Tang to Tang, ie, on the same side with each other.

[BaronVonchesto]

 

one other thing, my bigend bearings are the type with the tabs on them. does the bigend cap go on to the conrod such that the two tabs are close together or far apart? 

 

Both Mains and Big Ends go Tang to Tang, ie, on the same side with each other.

 

 

curious, why do all bearings tangs have to be on the same side as each other? aren't they just to prevent the bearing from spinning? or is it a balance thing?

[mini13]

becaus thats the orientation they are machined in, if you swap them round then you'll end up with an ofset hole and the crank will bind

[Spider]

 

 

one other thing, my bigend bearings are the type with the tabs on them. does the bigend cap go on to the conrod such that the two tabs are close together or far apart? 

 

Both Mains and Big Ends go Tang to Tang, ie, on the same side with each other.

 

 

curious, why do all bearings tangs have to be on the same side as each other? aren't they just to prevent the bearing from spinning? or is it a balance thing?

 

 

Nothing to do with balance, just as Mini13 said, it's the way they were machined.

 

The Tangs have nothing to do with preventing the Bearing Shell from spinning. The Bearing Crush or Nip is what prevents (or should !) that.

[DeadSquare]

If the tang doesn't stop the shell from spinning, what is it there for ?

[Spider]

If the tang doesn't stop the shell from spinning, what is it there for ?

 

Location.

[DeadSquare]

 

If the tang doesn't stop the shell from spinning, what is it there for ?

 

Location.

 

 

Ah, yes, I think I've got it, I hadn't thought of it like that.

 

If it hadn't got the tang, it might be inserted the wrong way round.

 

Of course;  the shell can't move inwards because the journal is in the way, so it doesn't need locating that way, and it can't move sideways because of the crank webs so it doesn't need locating that way, but it needs location because........er..............um.................Oh....................... I give up.   I can't think of any other way that it would need location.

 

Lol

[Spider]

Just locating so they are centred on the Journal.

 

It's the Bearing Crush (or Nip) that stops the shell rotating.

[mini13]

Some bearings have oil holes so need to be inserted the correct way, but also the tanf makes you put the bearings in centralised so the bearings can't rub against the fillet radius if present.