source of engine rattle 1147 herald

[Tipidave]

Probably difficult to diagnose on a forum... but any advice welcomed. Having had an unleaded head for my 1147 herald all is running beautifully with one exception... there is a loose and tinny rattle from somewhere. I have reset tappets... all good. I have run for a brief while with belt removed to rule out water pump and alternator bearing. Not this.  just wondering what else it might be. it is really only noticeable on idle and even then is not consistent. I had even considered the silver triumph letters on the bonnet because they are a bit loose. My trusty long screwdriver used as a stethoscope has not revealed anything untoward and I cannot for the life of me figure it out. Before the head overhaul the engine had overheated quite badly. Is it possible for the crown of a piston to just be striking the head? or would that make a good awful din? Finally do the timing chain tensioners go eventually? Any thoughts gratefully received.

 

[poppyman]

Have you kicking the exhaust when the engine is off? Could be a loose brkt or baffle in the silencer.

Tony.

[Pete Lewis]

as you have worked on the  head the manifolds have been disturbed , a exhaust contact.loose broken support as Tony says is very likely

pete

[Colin Lindsay]

Does it go away when the clutch is pressed? Might be the release bearing spinning.

[Pete Lewis]

out the box   we had a spitty with horrendous clatter , thought chain tensioner shot , but it was fine the cam sprocket had been centre popped on its 

mating face , even tho' tight it was not seated , flat he pips off and silence ...unbeliveable racket been like it since some past rebuild, why centre pop that area  heck knows 

but had me puzzled for a while 

but look for whats been disturbed ,  and have a good look at the valve springs for a fractured one

is this a rythmical or random chatter ???

pete

[Tipidave]

Thanks for the suggestions... I will investigate the manifold next. I did wonder whether excess play in the rocker shaft might be responsible. I have tried to investigate this but do not really know how to diagnose. I do not know what normal is like. I wouldn't describe it as rhythmical exactly more like something a bit flappy in the engine...seem not to notice so much on revving up more on revving down and idle.

 

[JohnD]

Try a mechanic's stethoscope - £3 on ebay - or just a broom stick, held to the ear, and then to vrious parts of the engine, to find where the noise is loudest.

[Tipidave]

Thanks for the reply. I have tried using a trusty large screwdriver for this purpose but really couldn't hear anything untoward. Tappets and valve gear all sound even across the head and as stated I have run the engine without belt to isolate water pump and alternator as a source of the noise.

[Pete Lewis]

check the fan bushes ? but they are belt driven so youve isolated that

has the gearbox exhaust support  bracket fractured ????

this doesnt seem to be an engine noise that you describe 

its more exhaust, radiator, side screen or whatever rather than any round and round rotational noises that will be rhythmical not random

Pete

 

 

[Tipidave]

Well with your help I think I have cracked it... the bulk of the noise was down to two manifold bolts that had worked loose... as suggested sovthankyou😊 the engine is very much improved. I have also identified that when closed the bonnet lettering is making a small noise which is really of no consequence. Once again thank you for all of your suggestions. Now singing like a Japanese sewing machine 😂

[Pete Lewis]

pleased it was something simple 

always think of the simple and cheap first before you open the idea of a deep wallet problem and always go back to the last job you did .

Pete