funny tapping noise since M30 conversion...

[gareth]

since getting the M30 running, i've noticed a wierd tapping noise. it is engine speed related, not road speed. it seems to be coming from behind the glovebox. it sounds a bit like a loud relay.

could it be something to do with the servo? (the inline valve arrived with the M30 conversion)

[Gwynleym10]

Best to rule some things out..

Injectors? (put a screwdriver against them and your ear, to see if its them)
Exhuast manifold?
Inlet manifold (possible?)

[gareth]

the injectors are pretty quiet and the exhaust doesn't blow at all (also on the wrong side).

the inlet did have a leak and that made a loud sucking noise but that's sorted.

the wierd thing is that it's definately related to engine speed but at a much lower rate. it's only there between 2k and 3.5k ish rpm and 'taps' at about the same rate as an indicator relay, maybe up to double. a lot slower than say a single exhaust blow.

very odd.....

[Andy335Touring]

Is your heater working properly ?

If not you have the heater pipes(on the engine bulk head) on the wrong way around, i had them on wrong to start off with.

[gareth]

hmm, could be...

i'll try swapping them this weekend to see if that helps.

the heater seems to work but on the drives i've been on so far, it doesn't really get up to temperature much.

did yours make any funny noises?

[Andy335Touring]

did yours make any funny noises?

Yes, before i swapped the hoses around it used to make the tapping noise related to engine speed and the heater worked fine till about 1.5-2k rpm then it got cold !

[Andy335Touring]

Have you got the new M20 temp sender on yet ?

[gareth]

cool, that's got to be the problem then. i tried shutting the heater off (temperature valve set to coldest) and the noise stopped.

i'll change the temp sender and pipe layout tomorrow and hopefully that'll do it.

[gareth]

Have you got the new M20 temp sender on yet ?

i have now, all is good there.