Disaster - cambelt failure, KV6 heads wanted - Page 3

StewartIngram · 25th December 2021, 12:40

Next batch, looking at the front of the engine.

Pic 14-Pic 19 - all looking at the run of the main belt. Unbelievable how much debris & dirt in there. Note where the belt has run off-centre on the pullies. (Also some debris has fallen on to the lower toothed pulled during dismantling).

StewartIngram · 25th December 2021, 12:51

Final batch for now.
Just to clarify, no markings found on the main belt. I haven't looked at the rear ones yet. All will be replaced, along with the bits at the front of the engine. I have secured a pair of (running) heads as well. Taking a break for Xmas.

Pic 20-22 show the water pump/ Looks like a small leak off the bearing?
Pic 23 - Tensioner arm; cleaned to enable it to be seen.
Pic 24 - Tensioner pully after removal, (allen screw untouched).

SD1too · 25th December 2021, 20:02

Quote:

Originally Posted by StewartIngram

Pic 24 - Tensioner pully after removal, (allen screw untouched).

This appears to be engraved INA which is strong evidence that it's the original. In that event it, and very likely the idler wheel too, would have covered 123,000 miles since they appear not to have been renewed at the 70,000 mile belt change.

The head of the Allen screw looks damaged in the photo suggesting a careless and quite possibly ineffective adjustment attempt. This would be consistent with the huge amount of fine debris, the scoring of the aluminium covers and the rust; none of which I would expect to see if the belt had suddenly snapped.

Thank you Stewart for these interesting photographs.

Simon

trikey · 25th December 2021, 20:47

Was the car losing water? I have not seen that amount of rust on the pulleys before.

xsport · 25th December 2021, 20:51

certainly does look like one of the original INA set ups. you dont see this stamping on bearings these days on replacement kits. im suprised that there was no prior warnings / squealing /rumbles etc . it appears to me that the belt did not break in one session. it may have lost a good long length of its width in one area. then carried on for some time half width , chewing and chewing the discarded parts of the belt between gears and covers. i dont think it was a sudden break. The shear amount of debris was astounding by shear volume , by which i believe was a long term build up. the belts do have large amounts of fibre glass re enforcement in them so what appears to be "wood" will probably be that. i doubt that the belt was renewed, or if it was renewed, was a used set up re used ? who knows , but what a mess .....

xsport · 25th December 2021, 20:54

Quote:

Originally Posted by trikey

Was the car losing water? I have not seen that amount of rust on the pulleys before.

yes looks like the water pump has rust coated inners. maybe stewart will know if oat was used full strength in his short ownership life.

xsport · 25th December 2021, 21:19

stewart , can you measure the belt width as a matter of interest please.i have a new gates belt here to compare. also when you do get another belt check how much length you have lost compared to new ... the two camshaft gears plus waterpump and bottom sprocker back plate should keep the belt in alignment on its inner run ok. the outer run can be pulled outwards by an outwards / downwards leaning tensioner pulley if its out or leaning down far enough. maybe its the other way it works !! wait till the crank pulley is inspected , paticularly the back plate as i know they can separate. thanks for the photos stewart. just one last thing stewart, can you check if there was a 3mm washer behind the tensioner main mounting bolt.( this is not the bearing bolt its the main pivot arm bolt. ) this has to be fitted when renewing the pivot arm tensioner, as the bearing will be well out of alignment if not.

StewartIngram · 26th December 2021, 09:52

Thanks for all the useful replies there. I'm not going out there till after Xmas, and its pouring down anyway, so I'll answer from memory for now.
The belt has lost width along its whole length; as well as the main break, there aresome other 'nicks', I'll take pics later. Also, if it is folded, there are signs of cracking.
I've had a water leak for a while, not serious though. During the summer I've been trying to find it, so have been running since then with only the remnants of antifreeze, not wanting to waste too much of it. I showed the leak apparent around the manifold gasket at no.2 cylinder, also the one I found when I dismantled, at the heater hose joint. But the water pump has traces of a leak from the bearing too. I'll measure the belt width, and take some pics of it. I'll also see if I can find the invoice for the work done - not that it will make any difference!

xsport · 26th December 2021, 11:31

thanks stewart. take a break and you will come back refreshed over christmas. i think the pump has been leaking for some time now .. hence the spare in the boot. Simon i think made the correct suggestion , when he said the belt was probably never tensioned properly. it may never have had the piston pushed back and pinned , before setting, and the belt only set by adjusting the hexagon key screw on the roller bearing. that would as time went on , and as more slack occurred , allowed the belt to try to move outwards. maybe the outer plastic camcovers were all that stopped it coming out of the teeth altogether . i was asking about the belt width as i wondered if it was the correct width . my new gates is 27 mm wide . the pulley bearing width is 30 mm on both tensioner and idler so quite a bit of forgiving width wise. sounds like the original pump , if thats what it is , was good for quite a few miles. oh and thanks for the updates stewart the pictures were very good. last thing ... get a bung put in that dipstick hole.you dont want that debris blocking up the oil ways on your new heads ....

StewartIngram · 26th December 2021, 13:48

Good point thanks, as soon as the rain stops I'll put a bung in it.

25th December 2021, 20:47	#24
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,766 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	Was the car losing water? I have not seen that amount of rust on the pulleys before. __________________ Lest we forget..

25th December 2021, 21:19	#27
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,643 Thanks: 358 Thanked 419 Times in 310 Posts	stewart , can you measure the belt width as a matter of interest please.i have a new gates belt here to compare. also when you do get another belt check how much length you have lost compared to new ... the two camshaft gears plus waterpump and bottom sprocker back plate should keep the belt in alignment on its inner run ok. the outer run can be pulled outwards by an outwards / downwards leaning tensioner pulley if its out or leaning down far enough. maybe its the other way it works !! wait till the crank pulley is inspected , paticularly the back plate as i know they can separate. thanks for the photos stewart. just one last thing stewart, can you check if there was a 3mm washer behind the tensioner main mounting bolt.( this is not the bearing bolt its the main pivot arm bolt. ) this has to be fitted when renewing the pivot arm tensioner, as the bearing will be well out of alignment if not. Last edited by xsport; 25th December 2021 at 22:00..

25th December 2021, 20:51	#25
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,643 Thanks: 358 Thanked 419 Times in 310 Posts	certainly does look like one of the original INA set ups. you dont see this stamping on bearings these days on replacement kits. im suprised that there was no prior warnings / squealing /rumbles etc . it appears to me that the belt did not break in one session. it may have lost a good long length of its width in one area. then carried on for some time half width , chewing and chewing the discarded parts of the belt between gears and covers. i dont think it was a sudden break. The shear amount of debris was astounding by shear volume , by which i believe was a long term build up. the belts do have large amounts of fibre glass re enforcement in them so what appears to be "wood" will probably be that. i doubt that the belt was renewed, or if it was renewed, was a used set up re used ? who knows , but what a mess .....

26th December 2021, 09:52	#28
StewartIngram Gets stuck in Rover 75 Connoisseur 2.5 V6 auto Join Date: Jan 2008 Location: Chatteris, Cambridgeshire Posts: 902 Thanks: 320 Thanked 159 Times in 127 Posts	Thanks for all the useful replies there. I'm not going out there till after Xmas, and its pouring down anyway, so I'll answer from memory for now. The belt has lost width along its whole length; as well as the main break, there aresome other 'nicks', I'll take pics later. Also, if it is folded, there are signs of cracking. I've had a water leak for a while, not serious though. During the summer I've been trying to find it, so have been running since then with only the remnants of antifreeze, not wanting to waste too much of it. I showed the leak apparent around the manifold gasket at no.2 cylinder, also the one I found when I dismantled, at the heater hose joint. But the water pump has traces of a leak from the bearing too. I'll measure the belt width, and take some pics of it. I'll also see if I can find the invoice for the work done - not that it will make any difference!

26th December 2021, 11:31	#29
xsport Posted a thing or two rover 75 club se Join Date: Apr 2011 Location: Leicester Posts: 1,643 Thanks: 358 Thanked 419 Times in 310 Posts	thanks stewart. take a break and you will come back refreshed over christmas. i think the pump has been leaking for some time now .. hence the spare in the boot. Simon i think made the correct suggestion , when he said the belt was probably never tensioned properly. it may never have had the piston pushed back and pinned , before setting, and the belt only set by adjusting the hexagon key screw on the roller bearing. that would as time went on , and as more slack occurred , allowed the belt to try to move outwards. maybe the outer plastic camcovers were all that stopped it coming out of the teeth altogether . i was asking about the belt width as i wondered if it was the correct width . my new gates is 27 mm wide . the pulley bearing width is 30 mm on both tensioner and idler so quite a bit of forgiving width wise. sounds like the original pump , if thats what it is , was good for quite a few miles. oh and thanks for the updates stewart the pictures were very good. last thing ... get a bung put in that dipstick hole.you dont want that debris blocking up the oil ways on your new heads ....

26th December 2021, 13:48	#30
StewartIngram Gets stuck in Rover 75 Connoisseur 2.5 V6 auto Join Date: Jan 2008 Location: Chatteris, Cambridgeshire Posts: 902 Thanks: 320 Thanked 159 Times in 127 Posts	Good point thanks, as soon as the rain stops I'll put a bung in it.