Prof. Monkey Posted July 23, 2006 Share Posted July 23, 2006 Oh god, car was using some oil, stunk of it all the time, so I did a little investigating..... Pulled one of the spark plug leads out to be greeted with more oil than you could shake a stick at. Took the black middle cover off to see swathes of oil in the spark plug recesses and a crack in the camcover at the front, where the bolt that goes under the wiring loom is. Not a happy bunny, they have been polished, could that have changed the temper of the material? Quote Link to comment Share on other sites More sharing options...
bromy Posted July 23, 2006 Share Posted July 23, 2006 Did you tighten them down evenly and to the correct torque? also these covers they wasn't the ones you had powder coated are they as this process can weaken alloy Quote Link to comment Share on other sites More sharing options...
Paul Posted July 23, 2006 Share Posted July 23, 2006 Possible that polishing in one area for a long period could cause loads of heat and result in cracking? Paul Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 23, 2006 Author Share Posted July 23, 2006 They were the polished ones and I only nipped the bolts up, Jim_supra will verify that I only nip them up to engage the rubber gasket. The cam cover had some holes in it, for the cover, that had been filled and polished, aparently with a welder? I bought them off someone who is reputable off here! Quote Link to comment Share on other sites More sharing options...
bromy Posted July 23, 2006 Share Posted July 23, 2006 The cam cover had some holes in it, for the cover, that had been filled and polished, aparently with a welder? Think you have probably answered your own question there Darren Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 23, 2006 Share Posted July 23, 2006 the holes that he is talking off are where the plastic spark cover bolts onto this in no way would weaken the cam covers i have heard off a set going before as supplied by me and this was simply because i over tightened them Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 23, 2006 Author Share Posted July 23, 2006 Apparently so! Thanks! Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 23, 2006 Author Share Posted July 23, 2006 Now I am stuck any suggestions as to what i should do? Quote Link to comment Share on other sites More sharing options...
paul mac Posted July 23, 2006 Share Posted July 23, 2006 Now I am stuck any suggestions as to what i should do? i'de get another set but this time DONT get them welded Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 24, 2006 Author Share Posted July 24, 2006 I agree with the no welding business, that was not my initial idea, but it was suggested to me by the seller. Here are the pics for you, I have pulled up the cover to get a picture... Very unhappy, on holiday cannot use the car Quote Link to comment Share on other sites More sharing options...
Tattooman Posted July 24, 2006 Share Posted July 24, 2006 Crikey that looks nasty fella, get that sorted as soon as you can dude. BTW, I like the ruler in piccie 3 that says "Shatterproof" (Quite relevant)... On a serious note, I would have thought that would only occur by over tightening on just that corner ??? Or has something fouled that corner and caused excessive vibration for this to occur ??? Good luck and I'm just glad that you have spotted it hopefully before any major damage has happened... Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 i'de get another set but this time DONT get them welded am sorry but how does adding material cause somethig to crack seriously i would like too know Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 and also it is my opinon (after fitting close to 30 off these)that the crack has een caused by stress after excessive touque figure am more than happy if he wants to return the failed one too me i will have it checked out by a independed person and or my fabricator Quote Link to comment Share on other sites More sharing options...
Digsy Posted July 24, 2006 Share Posted July 24, 2006 am sorry but how does adding material cause somethig to crack seriously i would like too know An ally camcover is such a thin part that the heat from the welder would have conducted through it very fast. The proper way to weld ally is to heat the part up beforehand, weld it, and then let it all cool down, otherwise you risk ending up with a distorted part. The heat at the weld point will be enough to knacker the material properties, anyway, so you'll probably get a locally weakened part. My guess is the the part distorted during welding and then cracked at a locally brittle point after being bolted down. Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 24, 2006 Author Share Posted July 24, 2006 Crikey that looks nasty fella, get that sorted as soon as you can dude. BTW, I like the ruler in piccie 3 that says "Shatterproof" (Quite relevant)... On a serious note, I would have thought that would only occur by over tightening on just that corner ??? Or has something fouled that corner and caused excessive vibration for this to occur ??? Good luck and I'm just glad that you have spotted it hopefully before any major damage has happened... Yeah but the thing is flat on top of the cylinder head, so I cannot see how that would happen... Besides a rubber gasket nips up the gap... Quote Link to comment Share on other sites More sharing options...
Digsy Posted July 24, 2006 Share Posted July 24, 2006 and also it is my opinon (after fitting close to 30 off these)that the crack has een caused by stress after excessive touque figure am more than happy if he wants to return the failed one too me i will have it checked out by a independed person and or my fabricator Of course, that's equally possible. Modern camcovers aren't designed to be tightened down - but the isolator bolts usualyl have some kind of compression limiter on them. Two questions: 1) Is there a fastener nearby the crack? 2) Is it the standard fastener? Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 An ally camcover is such a thin part that the heat from the welder would have conducted through it very fast. The proper way to weld ally is to heat the part up beforehand, weld it, and then let it all cool down, otherwise you risk ending up with a distorted part. The heat at the weld point will be enough to knacker the material properties, anyway, so you'll probably get a locally weakened part. My guess is the the part distorted during welding and then cracked at a locally brittle point after being bolted down. its been welded miles from where the crack is and this guy has been doing this for a great many years and would not have undertaken it if there was any risk Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 Of course, that's equally possible. Modern camcovers aren't designed to be tightened down - but the isolator bolts usualyl have some kind of compression limiter on them. Two questions: 1) Is there a fastener nearby the crack? 2) Is it the standard fastener? answer to question 1 yes am gonna have them returned to me so my fabricator can check them over if there is a flaw i will be happy to sort which ever way i can but in my opinon there wont be one Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 24, 2006 Author Share Posted July 24, 2006 Of course, that's equally possible. Modern camcovers aren't designed to be tightened down - but the isolator bolts usualyl have some kind of compression limiter on them. Two questions: 1) Is there a fastener nearby the crack? 2) Is it the standard fastener? Well I am biased but I would agree with you, I am not arguing with anyone, but I am a chemist, I have some knowlege of metalurgy and know the problems you can have with alloys..... The bolts have a rubber washer and steel washer built in and I know that this would distort before the cam cover was seated to hard and break.... Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 Well I am biased but I would agree with you, I am not arguing with anyone, but I am a chemist, I have some knowlege of metalurgy and know the problems you can have with alloys..... The bolts have a rubber washer and steel washer built in and I know that this would distort before the cam cover was seated to hard and break.... sorry mate but the last statement is not correct in my opinion it is as i say in my opinion not a crush washer and as i have said i have had a set do this by over tightening Quote Link to comment Share on other sites More sharing options...
Digsy Posted July 24, 2006 Share Posted July 24, 2006 Can someone post a picture ot a standard camcover fixing, please? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 24, 2006 Share Posted July 24, 2006 I'd say it was nothing to do with welding, it's either been droped and a possibly invisible fracture started, and the act of tightening the corner fastener has cause a piece to break off, or it's been overtightened. I well all manner of alloy castings and they don't crack due to this process. Quote Link to comment Share on other sites More sharing options...
supradibbs Posted July 24, 2006 Share Posted July 24, 2006 ok darren spoke to my fabricator and he has pretty much said what chris has just posted but he is happy to take a look and could possiably re weld it Quote Link to comment Share on other sites More sharing options...
bromy Posted July 24, 2006 Share Posted July 24, 2006 Do you know that you can now use tt cam covers on your n/a as you have the daveh inlet Quote Link to comment Share on other sites More sharing options...
Prof. Monkey Posted July 24, 2006 Author Share Posted July 24, 2006 Do you know that you can now use tt cam covers on your n/a as you have the daveh inlet Thats what it was! a TT cam cover.... Quote Link to comment Share on other sites More sharing options...
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