7 replies to this topic

[snoosbomb]

Hello to UK mini folks, from Canada , my first post here

 

My problem; what sounds like valve train noise , just a rattle [ from the frontish area ] that makes my car sound like a diesel , not dangerously loud , just an annoying background noise [ my other mini is smooth and quiet by comparison. ]

 

i tried to get rid of it by installing a new cam, followers, roller rock , timing chain , from MED Eng. but the only difference it made was to make it quiet at idle but as soon as i move the car in gear it appears . I now also have a 123 ign. and its the same with all timing curves . Its also no better or worse driving at any speed.

 

i did find that the Nural pistons had some scraping on the skirts and the only other thing i can surmise is that the followers are a bit tight. ???

 

thanks for any help ,

[Heintz]

Hi!  I understand form your post that you have just about replaced everything concerning the valve-train.  Have you considered your timing chain and its related sprockets/gears?  Secondly, you don't mention if your car has a tensioner on the timing chain.  Could it possibly be that?  And then of course it goes without saying, that I assume you have set the valve clearance to the correct setting...

Edited by Heintz, 09 January 2020 - 05:40 AM.

[snoosbomb]

hi , thanks , the new MED stuff works without a tensioner , there is some mystery about where to set the new roller rockers .017 - .012 ? but the sound seems separate from the rockers.  what i find curious is why just under load ?    [[to add its a 1275 ]] 

[cal844]

Check the timing

[Cooperman]

Check the camshaft retaining nut torque. I once had one that was a bit loose and the woodruff key slot in the after-market sprocket was a bit to wide and the sprocket was moving when the engine revved. The cam nut was tight, but not 'very' tight. It is easy to strip the thread by over-tightening. In the end some 'Loctite Bearing Lock' and slightly more torque on the cam nut did the job.

 

Alternatively it could be the timing chain just touching the timing cover.

[Ethel]

Exhaust manifold gasket leak is a possibility too.

[snoosbomb]

good suggestions thanks , never used the torque wrench on that.   [[ leak , maybe,, it does seem like a noisy engine

 

 

re timing ,  using the 123 , you lock the dizzy at 0 TDC , then it adjusts to 10. i found most advance curve worked best. i now even have more torque at 3500- 4000. with no additional noise like knock  i suspect i could even lock in at 5 static and work form there. And i.m running 9. 3- 4 CR on premium gas. There seems to be no hard rules about CR and advance.

[Rorf]

hi , thanks , the new MED stuff works without a tensioner , there is some mystery about where to set the new roller rockers .017 - .012 ? but the sound seems separate from the rockers.  what i find curious is why just under load ?    [[to add its a 1275 ]] 

 

There's your problem - sound increases under load then it is the timing which is too far advanced. I have always done the distributor timing by ear; take it out on the road and if you hear pinging when flooring the accelerator in a higher gear under load then retard the timing until you reach a point until where the pinging sound just disappears.

 

Need to find a nice quiet back road somewhere.