32 replies to this topic

[mykweb]

Model: Mpi Cooper
Year: 1997
Description of problem (please be as in depth as possible):

Hi guys

i am running an Mpi engine with 1.5.1 roller tip rockers. I am getting this unnormal tappy sound when the car is under load. As soon as you start to accelerate you get this tappy noise.

I have checked and rechecked the rocker gap, set to .17 thou. left them for a week then rechecked. But still the noise persists.

There is oil in the car, andwhen teh car is idling you can see the oil in the rocker cover. The noise is not present when the car is idling.

I know 1.5.1 rockers are unusally loud when running. But this noise only apears when under load.

Mike

[Ethel]

Worst case scenario would be a big end journal. How's the oil pressure,is it worse going uphill?


Sam, what you say is right but if it only happens under load it suggests something on the crank or in the drive train. How closely related to the engine speed is it? It ought to get noticeably worse as the engine warms up if it is something like a big end that rides on a film of oil.

[sam_o]

What rocker cover do you have on? With 1.5.1 roller rockers they tend to knock on the back of certain rocker covers, that's what happened with mine, you either need to get a metro rocker cover or the old black steel mini cooper one, which I have a spare one sitting at home

[mykweb]

its not the rocker cover as It does it with the orginal rocker cover in place.

The engine was only rebuilt a year ago, and has covered 7000 miles since the rebuild. Could the big ends go in that space of time.

The noise sometimes gets worse or quitens down when I go around a corner.

My oil pressure gauge is bust, i am in need of a new one

Mike

[MiniBonkerz]

as you pull away is it worse then for a few secs?

[Ethel]

7k makes a big end unlikely, enough to show up any build or running issues, but not enough for wear. Not impossible though. cornering might cause oil starvation or it might just exert enough force to make something catch. Try changing gear to see if it's defo engine speed related.

[mykweb]

not really, its there all the time when under load

If it is the big ends woudl there be any other indications?

And will it affect it if I continue to drive it? Well apart from trashing my crank

Mike

[Ethel]

Only had the one go, the oil pressure got gradually worse and after about 2 weeks of being ignored it let go 'n stuck the conrod through the block. It was a very predictable thud, I could have probably played a tune using the throttle

[mykweb]

7k makes a big end unlikely, enough to show up any build or running issues, but not enough for wear. Not impossible though. cornering might cause oil starvation or it might just exert enough force to make something catch. Try changing gear to see if it's defo engine speed related.

When you say changing gear? you mean like normal driving lol

I have not heard the noise when reversing the car if that helps

Also I have noticed that the oil dip stick is not showing a oil fluid level.

However I know there is oil in the car. When I changed the oil the other day, I stuck in 5 liters of 20/50 and it was still not showing a clear mark on the dip stick

Could this point to an issue?

When the engine was rebuilt there was a center oil pickup fitted.

Mike

[Ethel]

It the noise gets faster in a different gear it will be more likely to be the engine; if it stays related to road speed think gearbox etc. Can't think why the dipstick wouldn't show, but you could try blowing down the stick hole just in case there's debris doing something. There couldn't be a leak you've not noticed?

[mykweb]

drove the car home tonight from work and it seams like its getting faster. but only just

Would this indicate to big ends? is there any other signs that would point to big ends before I go ripping the engine apart

Mike

[Cooperman]

It ould be slight 'pinking' under load due to the igniton timing being slightly too far advanced. Check the timing.

[mykweb]

It ould be slight 'pinking' under load due to the igniton timing being slightly too far advanced. Check the timing.

car is an MPi and the timing can't be altered

Mike

[mykweb]

Last night i used my airline and blew down the dipstick hole,

ran the car for a bit then checked the oil levels. I am now getting a decent level.

Still having the tappy noise when driving thou, not impressed

So going buy folks responces it sounds like the big ends

Is this a nightmare of a job?

Mike

[mykweb]

This is going to sound like a dumb ass responce but

How come the tapping noise only apears when the car is in gear and driving. The noise does not apear when the car is idlling, or when the car is in gear and only a little throttle is applied.

Or when the car is being revved from idle?

totally confussed

Mike