First start, very hot....

mtb_tuli said:
aha, it´s a "twelve edge" nut, isn´t it ? What means UNS ?
Click to expand...
The nut is 12 point, or bi-hex and the UNS refers to the thread being Unified Special, meaning it's a specific thread and not necessarily standard dimensions.

edit.. When you have the big end nuts off check them for run-on torque before refitting them. There should be a minimum torque value with no load that indicates the nut's self-locking feature is still good for further use.
 
Thanks John, after 2 or 3 more engine rebuilts I will have a better view (or looking on the caps for the numbers....) :)
Regarding the self-locking , that would have been my next question, as normally you will be offered all the bearings, but not the nuts. Will check them.
Had to order a 12-point 11/32 socket, let´s see how it works.
 
Update.....
Good thing : I have new crank bearings now.
Bad thing : as soon as the engine is hot, at idle the "tacker-tacker-tacker" starts again :confused:
When I rev it, the knocking noise (it´s really sounding like a worn out crank bearing, but I have the feeling it´s more at the upper side) disappears, as soon as it idles, it comes back. Oil pressure better than before, but it does not go up to 30 lbs at 2500 rpm when hot (est 20 lbs). When cold, ok, perfect pressure, but that´s clear.
BTW, only 2 main bearing shells (lower ones) were ready to go (worst one the middle one), but all big end bearings were ok.
What´s normally the next suspect ? Slipped liner ? I read, that normally the 3.5 does not show this problem.
I had this noise, when I drove the car home from the Netherlands and idled out from the highway for a break, but then disappeared again. As the heads are "new" now, I fear it is one of the pistons or a liner. Hope not. But, a broken piston ring will not influence the oil pressure...
 
I'm no expert (in fact probably the opposite), but sounds like it could be one of the hydraulic valve lifters.
Particularly if the oil has drained out , as it might after a rebuild.
 
thanks Mike. I would prefer this, but lifters are fine and they cause more a tick-tick-tick. The noise my engine causes, sounds more drastic.
 
I've once experienced a pretty nasty 'knocking' sound which turned out to be coming from one of the exhaust manifolds, where a couple of bolts weren't sufficiently tightened up!
 
Manifolds all tight. The last days I had no time to look after more at the car, honestly was a little bit frustrated, so first bought a Grace One, Germany´s most powerful ebike. Battery down, charger missing, ok, winter project.
Back to my Rover, how can I identify a slipped liner ?
 
Slipped liner is highly unlikely, but would most likely be a knocking noise (rather than a tick-tick) at engine speed, pressurising the water system, loss of coolant, coolant in the oil or multiples of the above.
Pull the plugs and see if one is steam cleaned if you are losing water, and pull the dipstick to see if it's gone all moussy in the sump.
 
Thanks Paul,
yep, it´s more like a knocking (will try to make a video with audio), but disappears when revving. As the crank bearings (and big end) are new now and crank itself was ok, there are not so many other suspects. Across the forums, you may get the feeling, that slipped liners at a 3.5 is, as you said, highly unlikely, but the more you seek, you will find some 3.5 with this defect.
Ok, will check plugs etc this evening.

Edit, just thought about one thing this second :
When I replaced the cam, the front cam bearing was "a little bit" (what´s that, I know...) scored, I took some fine grid paper.
Are cam bearings suspicious to cause knocking noise ?

Jörg
 
Hi, Just come back to this thread, the symptoms you describe of knock starting when warmed up could be little ends or gudgeon pins knocking. They will probably last for quite while like that, the most cost effective solution would be a replacement engine, so you have a bit of notice.

Colin
 
Thanks Colin. No points for a slipped liner :rolleyes: ?
Big ends, little ends. Mama Mia. Ok, little ends sounds also realistic, as I do not know, what symptoms go with a slipped liner or a tilting piston. Frequency of knocking from a little end or a liner should be the same.
Anyway, as I found out, the base engine (above block everything is nearly new) has 239.000 km instead of 139 tkm, finding a block is the next thing, but I will go on with the MOT and drive it.
But, have to look for the different spark conditions. Am not sure, what you can do wrong with the cam, when sprocket and chainwheel markings say hello and cyl1 is on real tdc. What i did is, using the "early" position of the cam sprocket (it had early, std, late).
I do not know which carb feeds which cylinder.
 
If you think the noise is a little end (unlikely in my opinion) run the engine so you can hear the knock, and pull the leads off one by one, and if the noise goes quiet when a lead is removed, that's the one with the problem. If you locate it to one cylinder, then as you've just replaced the shells I'd look there first if the noise wasn't there before you started. I've only seen one slipped liner on a 3.5 block, and that just dropped, and didn't move to make a noise. I've never experiences little end problems either. It could be a piston problem though. All the above is speculation having not hear it.
 
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