The pumps diaphram may have a leak in it, alowing the prime to run back when stoped. If the hole is big enough it could alow the fuel to be running back into the crankcase(see if your oil level is ok and the oil dosent smell lke gas). If the fuel pump isint a financial burden then change the pump.
i burnt a set of main bearings out that way one time didnt catch it in time but this ole goat got wise that was the 1st thing i checked lol but have a new mechanical pump on its way so going to try this and if it works yipi if not will change the carb
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we are just waiting for the new fuel pump to get here, it seems that if you got a truck over 20 yrs they dont like to stock parts for it, which is a crock if you ask me, its a 67 ford with a 352 which is a 390 basically, i think you will find you dont have a rope seal it should be a neopream seal, its been along time since i tore into a 283 or a 327, but i'm sure you will get it, i used to take a fish hook and straighten it out and put a nylon string on it and run it over crank then stick the rope seal on barb and pull it through, but that was on the 170 cid ford engines .
) Mac
There is really no way untill you pop the main bearing cap, it seems there was alot of variation in the rear mains i would get both and take the one back you dont use, got our fuel pump on and solved our problem, back to yours, are you going be able to pull your oil pan without removing engine, just a thought.:thinking: Mac
oh yea
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