LOL

The first engine just seized on the M3 on the way to Popham (Crankshaft Oil Galley Plug/main bearings) 97yr

The second engine was newer, was looked after with regular oil changes every 3K miles, with good oil,
run for 2mins from cold etc although I did drop it at Brands, even though I managed to turn the engine off quick sharp. (main bearings again)
in both cases the crank was shot . . oil starvation, even though no signs of metal in the pickup filter:mad:
after a month started all over again, but if this one goes thats it for me.:rolleyes:

TopiToo

My 748 motor went bang just like you describe on my first ever trackday back in 1998. It had 45K kms on it at the time......
Ended up just getting a s/h one to replace it - loads cheaper than a rebuild.

Have fun with your decision!

Mine has 60K km and still going strong, perhaps I should have it checked over

Time for a update....

Sorry its bean a while but not had much time lately, As said before swingarm bolt was siezed so ended up cutting out to free frame and then cut swing arm to free from engine.

As you can see in the pics ,

Front cylinder shells have some damage but compared to rear cylinder look good , Rear is mullerd to hell crank is also worn quite badly so new engine needed rest ok so will sell of bits to help pay for engine and swing arm

Simon

Hello HUNT749

looks about the same as mine did after the stip down.
just another thought it is possible with this type of damage
the con rods will be shot too,

but I understand you can get them machined depending on damage,
or pick up a good set on ebay if thats the route you wish to take.

good luck

TopiToo

Hello topitoo,

I also think that the rods are shot as the surfaces are worn away quite badly . Was thinking about getting them machined but not sure yet on what to .
I know its a long shot but whats the difference in length between 748 and 916 conrods saw a crank and conrod assembly on fleabay and wondered ????

Simon

If you want to keep it as a 748 I have a good spare engine, freshly serviced, with oil cooler if you want it. Lmk

yes would like to keep it as a 748 , whats the history on engine as in age ,mileage etc and of course money required

just realised also 916 conrod and crank assembly wouldnt fit as stroke different isnt it!!

Simon