Arrows on piston crowns
Discussion
Hi guys, the pocketed pistons on the 5-ltr RV8 have arrows on top of them, just as any RV8. But there are no "domed shaped bosses" to meet those arrows on the conrods, as for the standard Rover 4.0/4.6 (acc to Rover overhaul manual). Well, perhaps this is of minor importance since I'm not putting new pistons/conrods in.
But... Shouldn't these arrows always point to the front of the engine when pistons are in place??? Strangely all didn't on mine, I noticed when I started taking the engine apart. Didn't think much of it then, but now that all is going in again, newly balanced, I do...
But... Shouldn't these arrows always point to the front of the engine when pistons are in place??? Strangely all didn't on mine, I noticed when I started taking the engine apart. Didn't think much of it then, but now that all is going in again, newly balanced, I do...
Steffo... yes, the arrows should all point to the front... but the rods are 4 one way and 4 the other so you get them running with the bottom oil groves on the rods the correct way (face to face on the big ends)...?
are you saying your pistons were wrong or the rods?... If you get the pistons out, the cutouts would be some top and other bottom?
are you saying your pistons were wrong or the rods?... If you get the pistons out, the cutouts would be some top and other bottom?
Edited by TVR Beaver on Monday 11th May 10:26
One side of the big end journal of the rod has a generous 45 degree champher. This side faces the crank pin. The other side of the rod big end is much flatter with hardly any champher at all. This side rubs against the inside of the adjacent rod. As for the arrows, yes, they face the front of the engine. HTH.
The rods are luckily right, with all bottom end oil grooves running against each other. And all pistons have the valve pockets pointing upwards, if that's what you mean with directions of cutouts. Otherwise it would be REALLY strange, I guess...
So, it seems like if I just switch side of a couple of piston/conrod-assemblies, from LH to RH banks, all arrows will be pointing forwards and all rods will still be facing each other correctly. Perhaps the "all-parts-back-were-they-came-from"-rule when rebuilding isn't that crucial when having new liners/rings, bearings etc.
I guess all this indicates that someone has been messing around with this engine before me, I just don't want to think that TVR Power neglected the arrow marks... Or, well, who knows.
So, it seems like if I just switch side of a couple of piston/conrod-assemblies, from LH to RH banks, all arrows will be pointing forwards and all rods will still be facing each other correctly. Perhaps the "all-parts-back-were-they-came-from"-rule when rebuilding isn't that crucial when having new liners/rings, bearings etc.
I guess all this indicates that someone has been messing around with this engine before me, I just don't want to think that TVR Power neglected the arrow marks... Or, well, who knows.
Forums | Griffith | Top of Page | What's New | My Stuff