1960 Morris Mini
Austin America A Series 1275cc engine
Working with a local Mini Friend. We basically got his mini on the road reciently. Long story short- He purchased the car after it had been parked for 5-7 years- body rusted out, and needed lots of repair. He took on the project, Body is nice- many new parts. He is now enjoying his car, or trying to.
We have been all over this motor - IT runs great- Pulls well. But idle . and low rpm. 1000ish or lower , there is a very audible CLACK what seems to be in the dead center of the motor. Think Mercedes TD Deisel at a stop light. We have chased Valve tightness. Rockers. Not the clutch, not anything exteror. Valves all stay right in specs. Once you add some gas the noise goes right away.
compression is fine among all - 130 130 125 130
Enough is enough- we had to tear into this thing. among another project. We took motor out today . Split it all apart...
Took head off- nothing drastic. Little carbony all even color in Cyls. - Head gasket leaking a Tiny bit- but not horrible.
Piston bores show cross hashing still.
Pulled one rod apart with bearing out - .010 Bearings installed!! this motor has been into. Bearings look nearly new. Pulled 2 pistons out- they look nearly new too.
crank has been ground on / bottoms of rods have been smoothed.
We were searching for Loose Knocking Wrist Pins...Number 2 + 3 have what look like new pistons inside. Scratching head- we havnt pulled number 1 / 4 but will. No noticible Slop in the wrist pins.
What is next to check? Cam looks Good from looking inside. Looks like cam bearings were put in too.
Can any one tell the nominal value that the crank should have been turned to for the .010 Bearings? What if the bearings are loose?
IDeas needed....
We are thinking someone worked this motor before he purchased, and this engine clack is why it was parked. They did an engine build, but something is just not right.
Can post pictures if necessary. Havnt totally stripped motor yet.
Thanks for the thoughts.
Edited by SomethingNew71, 11 September 2012 - 06:28 PM.
