1987 Micra Knocking Noise

[ollyr]

Hi,
First of all, cheers for the site, i found loads of useful info on here!
Anyways i have a 1987 Nissan Micra SGL Auto, its done 78000 miles and has been extremely reliable. Recently I have noticed a knocking noise which seems to get worse every time there is any load on the engine, i am thinking that this might be the water pump, but not sure.

If it is how much would it cost to do the cam belt and pump at a garage (average). I really dont want to scrap the old girl yet, it was only ment to be a stopgap car but now I like it too much -and the fact that ive just put on new rear shocks and patched up the arch!

Cheers,
Olly.

 

[AMY]

Have you run low on oil recently? it could be a number of things making a knocking noise. Consistent knocking under load is usually a sign of worn big end bearings. Does it sound as though it's coming from the engine?

 

[ollyr]

Cheers for the reply, Seems to make the noise sometimes at certain revs, Ive never run below the low mark and since ive had the car its been changed regularily, i know my nan had it before and it was not serviced for a long time.
Doesnt overheat and still seems to drive fine, its only done 78k so I'm hoping for a few more yet!

cheers, olly

 

[AMY]

It could be so many different things, it's hard to say without hearing it. If it's intermittent It's probably not the big ends, unless they are just starting to go. Is it a loud knocking or more of a tapping? A few of the easier things to check that it might be are, check the exhaust manifold for leaks, try a higher grade of fuel, check valve clearances and ignition timing. It might not be any of these, but the checks I have highlighted should be part of the routine maintenance anyway. Is there any reason why you suspected the water pump?

 

[ollyr]

Hi,
Have just changed the points recently and i didnt use a dwell meter I just used feeler gauges. So could possibly be that. I checked the tappets today and apart from a couple tweaks they were spot-on. I only thought it was the water pump because I read on another site they are a weak point. To be honest I used the old screwdriver trick to listen to the dizzy, the rocker cover, alternator etc. and It didn't seem to be anywhere!

Cheers for the help

I did notice the fuel pump was hissing even after the engine stopped for a while tho ?

 

[sonic]

surely the K10 auto has a mech fuel pump not an electric one, you shouldn't hear it at all.
the Knocking could be something as simple as the exhaust knocking against the body or axle or something, but then again it could be the big ends, particularly if its only under load. is the knocking there with the car stationary and in neutral ?

 

[ollyr]

Hi, yes it is a mechanical pump but if you put a screwdriver on it and listen you can hear it hissing? Also read on another site that fuel pumps are prone to go and leak petrol into the oil - so hope that isnt happening!
Oil doesnt smell to dodgy tho?

 

[sonic]

Ok, using the screwdriver trick you will hear a hiss from the pump, but that's only because of the mech movement inside the pump, as for fuel leaking into the oil via a faulty pump that's extremely rare, it wouldn't explain the knocking either really, but as above is the knocking there in neutral and stationary ?

 

[ollyr]

The noise seems to be fine if you are just keeping a constant speed its when you put the throttle down it makes the noise which is sort of rattly. The fuel pump still hisses when the engine has stopped for a minute tho?
Cheers, olly.

 

[sonic]

Where are you based Olly ? perhaps someone local would be willing to give you the benefit of an experienced ear, but it does sound like big ends, as for it being a 'stopgap car' spend a bit more time in it and do a little more to it and you will be hooked.

 

[ollyr]

I am in Beaminster, Dorset about 10 miles from yeovil.
My Dads gonna have a look soon so ill see what he thinks

as for it being a 'stopgap car' spend a bit more time in it and do a little more to it and you will be hooked.

Well I had a mini on the road and I liked that but I gotta say the micras a lot more comfy and still a simple car!
Cheers for you help