1988 Isuzu I-Mark bogging

i have an 1988 isuzu i-mark non turbo that blew a headgasket i did all the steps resurfaced the head and all and put it back together and it ran great but then all of a sudden when i start it it boggs kinda like a surge at idle and when i give it gas to go it almost stalls out but if i barely tap the gas it gives it enough to accelerate