base190380

at last ive found out what the noise is. I have really worn valve guides and the 3rd cylinders inlet and outlet valves have lots of sideways movement on them so could this most likley cause the noise. I have compared it with another cvh head and the other head has no movement at all when shaking valves sideways. Any advice much appreciated. has anyone had this b4?

haz87

yup, i just bought another head instead,lol. Cheaper than doing the guides in the end

base190380

hi haz87, u had the same prob as me didnt you. has anew head solved it then and did you have loose valves in their guides too? cheers

haz87

Yup shagged valve guides was the cause of one of the many noises ive had in the past few weeks. The other was a fecked piston ring
However the fecked valve guide also cause ALOT of blue smoke constantly.
Tho saying that if any of your guides are loose it needs adressing whether its the cause of the noise or not

base190380

haz 87 did you get to the bottomo of the noise on your car. just wondering if you could give me some pointers.

Anyway i have since changed cam, followers, rockers, cylinder head and still have the same noise and backfiring when lifting off throttle at speed. Also checked piston crowns and timing and all seems good. After fitting the new head it seemed okay for about a hour and then it went back to normal. Any other ides guys. I was thinking maybe a fuel injector fault but never really had probs with injectors before!

base190380

Okay, after weeks of work and sicking myself, i think ive found my problem. One of the valve springs on the 4rd cylinder is shorter in length than the rest, so i assume that this would cause the rattle and backfire. Any thoughts guys? Ive sent head away for recon with new springs anyhow.

SafeChav

well its certainly not doing you any favours........

lewis_lisa

i had same symptoms and it sounded like a top end rattle but turned out a bolt had worked loose on 1 of my rods and i never got it checked and it blew a hole in my block i hope this is not the case with yours m8 but its def worth getting checked out just incase

hope this helps

scubyo

Yes i have the same issue with the noisy tapping/knocking and on start its not bad but gets worse once warming up. I also have changed to a new cam and new followers, good quality ones and have swopped out the rockers from another head, nothing changes the noise. So i am getting a replacement head skimmed and changing everything. I had a engine builder and he suspects the valve guides or worn camshaft bearings.

I let you know if it works

scubyo

Just removed Cylinder head and the knocking always seemed to be at No.1 end, when head was disassemble No.1 injector has been over fuelling as looked wetter as shown in picture so i will replace with another tested injector on when i refit new cylinder head. On investigation on old head i have found to be excessive wear in the bore where the hydraulic tappet locate. I can see a wear line and a lot of sideways movement when i test fit.

nigel b

get the cam and tappet bores measured for size while it is off

90_spec

HI Scubyo, mine is the same scenario, the engine is quiet as a mouse and very smooth when cold, but once its warm, the tappets can be heard in the car. Its only done 400 miles since i rebuilt it, new Cam, lifters, bearings everywhere etc, So id be keen to know if you found anything interesting with yours past the Cyl1 being wetter, I've run it in on Halfords 10/40 semi synth, and its about due for a filter and oil change, so any advice would be useful right now,
Ta
Rich