Gren_T Posted September 6, 2020 Share Posted September 6, 2020 Hi Chaps, I have a 300TDI in my auto 90 however it has recently developed a tapping noise, the noise appears to come from the rearish of the engine as it seems louder when standing beside the wing but almost disapears when standing in front and seems to be 3 ticks. I have removed the aux belt and the nose is still there so it is not an ancillary, I have adjusted the tapets and checked all around the engine with a stethoscope and cannot locate the noise. The ticking gets faster as the RPM rise but do not get louder, I have had a look at the flexplate throught the inspection hole and cannot see any evidence of cracking. There seems to be no loss of performace- ha.! nor any other issue such as vibration I can feel. I have added an audio file of the noise if someone has an idea please throw it out as this is driving me quietly mad. Cheers.๐ 300TDI Engine tap.m4a ย ย Quote Link to comment Share on other sites More sharing options...
western Posted September 6, 2020 Share Posted September 6, 2020 Look at the rocker shaft & valve caps, rocker arms.ย Quote Link to comment Share on other sites More sharing options...
Gren_T Posted September 6, 2020 Author Share Posted September 6, 2020 Hi thanks for the reply, I've checked the shaft & arms when i adjusted the tappets the caps are free and move easily and none are cracked.! when i checked with the sethoscope there was no trace of the ticking noise. again thanks for the help.๐ Quote Link to comment Share on other sites More sharing options...
steve b Posted September 6, 2020 Share Posted September 6, 2020 Exhaust manifold gasket leak ?ย Steve Quote Link to comment Share on other sites More sharing options...
cackshifter Posted September 6, 2020 Share Posted September 6, 2020 Or head gasket blowing at the back from No.4 cylinder. If it's that you can probably feel it by sticking a finger near the head gasket joint at the back of the engine - there's a bit of a ledge where the head is a wee bit shorter than the block. It sounds like a badly adjusted tappet. You'd feel it as puffs of gas. If it is that, don't delay fixing it as it can damage surfaces. Quote Link to comment Share on other sites More sharing options...
Gren_T Posted September 6, 2020 Author Share Posted September 6, 2020 300TDI tapping noise.mp4 Ok thanks for the suggestions, I've checked the headgasket and there is no evidence of blow same with the manifold. It does sound as if it's the rear of the engine/belhousing area. Quote Link to comment Share on other sites More sharing options...
Gren_T Posted September 6, 2020 Author Share Posted September 6, 2020 Ok thanks for the suggestions, I've checked the headgasket and there is no evidence of blow same with the manifold. It does sound as if it's the rear of the engine/belhousing area. ย 300TDI tapping noise.mp4 Quote Link to comment Share on other sites More sharing options...
steve b Posted September 6, 2020 Share Posted September 6, 2020 unlikely you would feel an exhaust blow from manifold joint unless it's conveniently in the one or two places you can get at . Get a new gasket and pull the manifolds off - you could remove the inlet manifold to allow a much clearer view first ?ย If it's not that then I would agree about the HG being the next most likely cause .ย I know you've already checked the tappet clearance but a second look to confirm before you pull the head ?ย cheers Steve b Quote Link to comment Share on other sites More sharing options...
dave88sw Posted September 6, 2020 Share Posted September 6, 2020 Brake vacuum pumps often tick when they're giving up. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted September 7, 2020 Share Posted September 7, 2020 I had a 200Tdi that had a tik when cold. Eventually the engine was stripped for sared, The head was sold then the block, we never found any marks or any reason for the knock ย Quote Link to comment Share on other sites More sharing options...
Snagger Posted September 7, 2020 Share Posted September 7, 2020 If the noise sounds like someone flicking a taught sheet of paper, then the head gasket is the likely cause, probably between the fourth bore and the back face of the engine, which is a common failure point on Tdis and especially the 300. Quote Link to comment Share on other sites More sharing options...
monkie Posted September 7, 2020 Share Posted September 7, 2020 I would get a replacement head gasket (Elring) and renew it as it is easy enough to do. If you don't want to do that then I think it is worth buying a new exhaust gasket and replacing it ensuring the manifold is torqued up correctly just to rule it out.ย ย Quote Link to comment Share on other sites More sharing options...
Gren_T Posted September 7, 2020 Author Share Posted September 7, 2020 Thanks again for the replies, Tonight I pulled the Vacum pump and stripped off the air cleaner and pipework so I could see the rear of the head. With the engine running the tick is still there ๐ฅ though only as it starts to warm up .? after dousing the back of the head with brake cleaner there is no blowing from the rear of the head as i'd have seen the liquid blow off. So tomorrow I'll refit the vac pump and strip off the manifolds... ย Cheers๐ Quote Link to comment Share on other sites More sharing options...
Gren_T Posted October 29, 2020 Author Share Posted October 29, 2020 (edited) Just an update for anyone with a similar noise in the future.. As sugested I pulled the exhaust manifold and found it was blowing on #4 cylinder that was replaced, but the noise was unchanged. I bought a replacement flexplate, pulled the transmission and found the flexplate was good and slightly thicker than the replacement I had bought from Ashcroft. The engine was run up without the autobox and no noise..! Looks like the sound is coming from the autobox, there is no change in performance, I replaced the oil & filter which came out clean there were no leaks around the TQ so I'll run it until it goes clang and give me a chance to save up for a new box. Thanks for the replies๐ Cheer. Edited October 29, 2020 by Gren_T 2 Quote Link to comment Share on other sites More sharing options...
monkie Posted October 30, 2020 Share Posted October 30, 2020 Good to have follow up. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.