RAY786 Posted September 24, 2010 Share Posted September 24, 2010 I have a range rover 4.0 petrol/lpg. It has noisy tappets so i bought set of 16 new ones. Took it to a garage and the mechanic opened it and said the camshaft and other gaskets are fine just the tappets needed changing so he changed them. I went to pick vehicle up and te mechanic said take it on motorway due to air going into tappets when getting fitted. So i drove on motorway abot 15-20 miles still tapping away. Rang the mechanic and he said not it may need some mineral oil and a flush. What can i do now? Quote Link to comment Share on other sites More sharing options...
landmannnn Posted September 24, 2010 Share Posted September 24, 2010 I know it isn't the proper solution but I have found stp or wynns hydraulic tappet treatment does the trick. Saying that if you have paid your mechanic get him to solve it. Quote Link to comment Share on other sites More sharing options...
RAY786 Posted September 24, 2010 Author Share Posted September 24, 2010 yeah i paid him but what if that doesnt work? he said the cam shaft etc was not worn so he cannot say thats what has caused it. I dont know what it can be. The garage is confident its defo the tappets. Quote Link to comment Share on other sites More sharing options...
Roverbo Posted September 24, 2010 Share Posted September 24, 2010 Hi, have you seen that the camshaft is OK? If it hasn´t been changed by now, it will shure be worn down a bit. IMHO tappet noise can only be caused by Def. tappets (well, not now) Low oil pressure (to thin oil ? - should be 15/40, 20/50 or at least 10/40) - or blocked oilfilter (I had a Coopers that failed). Blocked oilways to rockers/tappets (can you see oil through the oilfiller hole? Worn pushrods (measured the rods?) Worn camshaft (they only last say 50-100.000 km). As the V8 tappets are hydraulic, they are self adjusting and very foregiving to wear. If you can hear the tappets more than 5 secs after start, something is wrong. Regards Bo Quote Link to comment Share on other sites More sharing options...
SteveRK Posted September 24, 2010 Share Posted September 24, 2010 If there are lots (more than one) of tappets rattling away it might point to oil starvation due to a blockage - if it sounds the same as before they were replaced then even more likely to be a blockage somewher in the upper part of the engine, but heh' surely the mechanic would have spotted lack of lubrication? Quote Link to comment Share on other sites More sharing options...
Quagmire Posted September 25, 2010 Share Posted September 25, 2010 On the RV8 you should always change the cam when changing lifters too. By replacing the lifters only you run the risk of turning your cam into swarf... Quote Link to comment Share on other sites More sharing options...
Ally V8 Posted September 25, 2010 Share Posted September 25, 2010 I'd go with Quagmire on this,and also add that lifter noise is often misdiagnosed - worn rockers/shafts are usual suspects. Quote Link to comment Share on other sites More sharing options...
Pollarhullar Posted September 27, 2010 Share Posted September 27, 2010 I had this some time back on a 3.9 1992 Classic. New oil and filter combined with an engine flush and added wynns tappet remedy with new oil, new oil been the manufacturers recommended. So far this has been succesful, bearing in mind a 92 is an elderly lady and I now probably change the oil more frequently than possibly necessary. Quote Link to comment Share on other sites More sharing options...
sheltie50 Posted October 2, 2010 Share Posted October 2, 2010 If you can hear tappet noise on a V8 something is very wrong, I have seen camshafts worn almost round and still no noise. You should check oil pressure and circulation, change the oil filter etc and listen to the engine it will tell you whats wrong by the speed of noise. Can you see oil if you remove the filler cap, are the rockers dry. Sometimes it can take a while to pump up hydralic lifters but I think your past that stage. I really think you have an oil pressure problem! Quote Link to comment Share on other sites More sharing options...
zim Posted October 3, 2010 Share Posted October 3, 2010 On the RV8 you should always change the cam when changing lifters too. By replacing the lifters only you run the risk of turning your cam into swarf... Ditto. Quote Link to comment Share on other sites More sharing options...
Fatboy Posted October 3, 2010 Share Posted October 3, 2010 As the others have said, just replacing the lifters without the cam or rockets / shafts is a false economy. When tappets get seriously worn, they can have a rim of carbon or slight belling round the bottom so they really need to be pushed down and out so that this rim does not get pulled up the bore of the housing, potentially scoring it. As he only replaced the tappets, he had to have pulled the tappets up... so maybe scored the housing so that they are not pumping up but are instead bleeding down too quickly... Quote Link to comment Share on other sites More sharing options...
paintman Posted October 3, 2010 Share Posted October 3, 2010 You never ever change just the cam or just the tappets on the Rover V8. They wear together against each other so must be changed as a set. The old component will trash the new in very short order & it may well make little difference to the original problem. Your mechanic has given you very bad advice. Have a look at this link from RPi: http://www.v8engines.com/engine-4.htm#worncams Don't be tempted to use cheapie tappets - genuine parts only! Quote Link to comment Share on other sites More sharing options...
Range Rover Blues Posted October 3, 2010 Share Posted October 3, 2010 I'm told a lot of cheap tappets (AKA cam follower or lifter) are not worth fitting but assuming you bought good ones, assuming also that you havn't had any head work done that has made the preload incorrect then I'd say the cam is worn or you have an oil supply problem. When fitting they should be soaked in oil overnight to allow the air to settle out, I don't get the business about driving on the motorway but we live and learn. The cam is ground non-parallel so that the follower rises on the back edge (IIRC) of the cam lobe. Other manufacturers might make the follower sit off-centre on the lobe to acheive the same effect. This means that when 'lifting' the follower is running on a thin contact patch at it's outer edge, the back edge of the cam lobe. What this does is make the follower spin so that it scavanges oil, it also evens out the wear on the pushrod. Spinning followers are commonplace in the motor industry and on overhead cam engines the valve may also spin. Now if you were doing the work yourself I'd say crank the engine with the vallay gasket removed and watch the followers. If one or more don't spin then they will make a noise. It's because the scavenging is what fills the follower with oil to take up the slack, so I'm told. On old Ford engines the tapping is caused by side-play in the tappet within it's housing but I don't think it's an issue with the V8 even in ones with gungy oilways (of which I've seen a few). Oh, one other thing, weak valve springs? Out of interest, what sort of MPG do you get? high fuel consumption is associated with poor valve-timing often caused by a worn cam chain or worn cam lobes, even before the followers start to rattle. I replaced my followers with brand new ones and it made no difference, but I agree if you have paid someone to do the job then they ought to be doing it so take it back and have a chat with the guy, see what he thinks. Quote Link to comment Share on other sites More sharing options...
paintman Posted October 6, 2010 Share Posted October 6, 2010 "I replaced my followers with brand new ones and it made no difference," Without replacing the camsahft as well I'd be surprised if it did. Go & have another look at the RPi link I put. Quote Link to comment Share on other sites More sharing options...
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