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View Full Version : Lobes Slipped on camshaft



ben0069
11-08-2012, 09:52 AM
Hi all, some of your wisdom needed please.
After Changing air con and power steering belts the other day, we also checked pump timing which was slightly out so we adjusted that too. All good went on a couple of trips, usual everyday stuff.
A few days later the car lost power and was ticking over horribly, and when I say lost power it would hardly drive on the flat, the revs would not go past 2500 and once the clutch was released it was almost stalling.
We have stripped it down and all the belts are still in tact, pulleys are ok. The timing is still '**** on' on both sides of the engine and everywhere else and there are no tight spots when turning the crankshaft.
We slackened off the fuel pipes on one side, cranked it and nothing. Did the same on the other side and it fired ok.
Next we took of the rocker cover to reveal the camshafts and some of the compensaters had come away fron their seats and 3 of the tappett(i think) had snapped; ie the rounded head had broken away from the shaft.
So we removed one of the two camshafts and two of the lobes had slipped.
The things I dont know are;
What causes this kind of problem
Is there usually any further damage to look for
Do I just replace the one camshaft and all compensaters and tappets or while the engine is in this state would it be better to do all 4.
Do I go with oem parts or are any others recomended
And if you can think of anything further I need to know please inform me.

The car is at 165000 miles, and this is the first major breakdown, I have had it since 11/08/08 andit had 65000 on the clock, timing belt changed at 70000 and at 140000. I have changed the oil every 6000 without exeption.
Any advice would be great, thankyou.

meganall
11-08-2012, 10:02 AM
what do you mean the lobes have slipped ??

ben0069
11-08-2012, 12:43 PM
The shaped pieces that sit along the camshaft have moved from their original place and I can see daylight between them and the shaft itself. I called them lobes, I don't know what they're called, pear shaped or egg shaped if you like.

meganall
11-08-2012, 01:45 PM
your right there called lobes
i would say they were heat fitted on the shaft and yours have probably got hair line cracks in them allowing them to expand and come of the shaft, the possible cause would be lack of oil causing excessive heat ??
i would check all oil filters meaning the one in between the V of the engine (mist filter i think its called) the main oil fiter and your oil pump main gauze in the sump
you might be lucky and get all 4 from ebay etc and i would replace the 2 on that bank and keep the 2 for spares or while your at it do all 4 then its only having to do the cambelt once
i might have a few tappets somewhere from a akn engine if thats any help
also what cam has gone the piggy back one or the one with the pulley on ??

meganall
11-08-2012, 01:47 PM
if you were closer i would come over and give a hand, i have got relatives at camarthan but there down here atm bliddy typical, as i could of seen them and seen you at the same time ;)

Peter D
12-08-2012, 02:26 PM
Production cam shafts do Not have pressed on lobes they are machined from a solid, either a chilled casting or a billet. Regards Peter

zollaf
12-08-2012, 02:31 PM
except some modern psa engines. imagine how horrified i was to find the lobes pressed onto a shaft when rebuilding a 1.4 hdi. the lobes on that had turned and we couldn't work out how there was no radius between the shaft and lobe.

Crasher
12-08-2012, 02:49 PM
"They are machined from solid but the heat treatment can make the lobes brittle causing them to break away like they were pressed on".

I have heard of this but never seen it and that was the official reason I was given.

meganall
12-08-2012, 03:31 PM
if the cam was made from a billet piece of metal then if the lobes broke away the cam would be broken at that point and the following lobes wouldnt move ??

ben0069
12-08-2012, 04:31 PM
quite right meganall, this is how it looks,

meganall
12-08-2012, 05:10 PM
defiantly looks like a pressed on lobe to me but been wrong before :D is that cam the pulley one or the piggy back one ??

Peter D
12-08-2012, 06:32 PM
Need more photo's but it appear to be oil starvation and you have severely damaged the shaft they are made from a solid, you may well discover the entire head is distorted and cam bearing well melted. Regards Peter

ben0069
12-08-2012, 06:37 PM
sorry meganall been a busy weekend, I should have replied to your earlier post, it was the piggy back one and thanks for the offer of coming to visit and have a look.

Peter D
12-08-2012, 06:42 PM
I suspect the lack of oil has caused the cam to follower surface to become seriously hot and the chilled cast shaft has softened and rotated around it's axis. I suspect you will find metal particles all over the engine. Big job to clean up. I inspected one of these a couple of weeks ago at an independant garage and there was metal everwhere. Regards Peter

ben0069
12-08-2012, 07:35 PM
There's a febi bilstein kit at onlinecarparts.co.uk for £777+vat for the allroad that includes 4 shafts and all the tappets and compensaters. Are febi a reliable make to go for ?

zollaf
12-08-2012, 07:41 PM
i would say febi are about the best aftermarket parts you can buy. i fit a lot of their stuff and never have problems.

meganall
12-08-2012, 08:57 PM
COMPLETE KIT 2.5 TDI V6 AUDI VW OF CAM FOLLOWERS, HYDRAULIC TAPPETS & PADS 2,5 | eBay (http://www.ebay.co.uk/itm/COMPLETE-KIT-2-5-TDI-V6-AUDI-VW-OF-CAM-FOLLOWERS-HYDRAULIC-TAPPETS-PADS-2-5-/320960230904?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4abab875f8)
i paid just over £100 for the tappets from mill autos

ben0069
12-08-2012, 09:23 PM
COMPLETE KIT 2.5 TDI V6 AUDI VW OF CAM FOLLOWERS, HYDRAULIC TAPPETS & PADS 2,5 | eBay (http://www.ebay.co.uk/itm/COMPLETE-KIT-2-5-TDI-V6-AUDI-VW-OF-CAM-FOLLOWERS-HYDRAULIC-TAPPETS-PADS-2-5-/320960230904?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4abab875f8)
i paid just over £100 for the tappets from mill autos

I had a look at the kits on ebay but wasn't sure wether the qaulity would be great ?

meganall
12-08-2012, 09:51 PM
its made in germany so should be ok

meganall
12-08-2012, 10:01 PM
PREMIUM 2.5 TDI V6 VALVETRAIN, V-BELTS & TIMING REPAIR KIT AUDI A4 A6 A8 PASSAT | eBay (http://www.ebay.co.uk/itm/PREMIUM-2-5-TDI-V6-VALVETRAIN-V-BELTS-TIMING-REPAIR-KIT-AUDI-A4-A6-A8-PASSAT-/320946326569?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4ab9e44c29)