so im looking at picking up an L24 that was removed from a car that a sbc was put into. I was told it was rebuilt about 2 yrs ago, new gaskets and valve seals, and was only in the car running for about 6 months until the small block went in. The exhaust manifold was was removed when i went to go check it out and there seemed to be A LOT of carbon buildup, like chunks would come out when i stuck my finger into the port.
just wondering is this could be from running really rich? or a possibly oil leak? not too sure, just looking for some input, i have not had good luck so far with used l series motors, dont want it to happen again :/