After some trackdays and trips to Belgium, my xflow started to create some knocking noises. Big end bearing down the drain and in doubt if the crankshaft can be salvaged

Good xflow engines are becoming very rare over here and i need to win a kind of lottery first.....

Found another engine, history unknown, but most likely it was mounted in a Fiesta mk1 super sport. Shortened timing cover, sump turned 180 degrees and a waterpump with an outlet on the alternator side of the engine. All signs of an engine mounted in a FWD car. The engine code is 791m6015ab (yes, ab not ba !)

I have to install the shortened sump of my 'old' engine what creates a problem with the dipstick. On this engine the dipstick is at the timing chain side and not at the flywheel side. This problem however can be solved.
xflows are famous for heavy breathing. On standard xflows the crankcase ventilation hole is just above the mechanical fuel pump. Surprise ! There is no hole on this engine, WTF ?

Help ! Anyone familiar with this engine type ?

FWD X-Flow block is a 771M, block itself should be the exact same as a RWD 711M found in old Escorts etc apart from fixings for a upper RH mounting which allows fitment in the Fiesta.
I've never actually heard of a 791 block? Is it some kind of pre-x-flow.

Edit - actually just remembered these are 1600, not sure about a 1300 block.

[Edited on 4/7/14 by Scuzzle]

The first two digits of the engine code represent the release year of this particular type of engine. After the pre-crossflow, the first real crossflow was released in 1968 with the 681 prefix, followed in 1971 with the very common 711 blocks. Ford released the Fiesta mk1 in 1976, starting with a 957 and 1117 cc engine. In 1977 the 1298 cc version was launched, hence the prefix 771.

So, my 791 block was released in 1979 and build in january 1980 because the stamped in engine number starts with AB.

As mentioned the mounting points on a 771 block differ from a 711. But, on my 791 block the mountings are a exact replica of the 711 !

It seems plausible that this engine was fitted in a non-Ford FWD car from that era.

[Edited on 4/7/14 by strikerguy]