1970 fj40 with the early F155 engine. Replacing the fuel pump because engine was cutting out at ~55 mph. In-line pressure gauge showed ~5 psi at idle and would drop down to almost 0 in 3rd gear at 55mph.
New fuel pump looks identical to the old but doesn't go into the block far enough to bolt in. The small spring on the old pump was broken (two pieces laying inside the arm) and I'm assuming the spring on the new one is keeping it from going in. According to Spectre, 58'-73' are all the same. Cruiser Corps sells a simpler-looking pump (smaller and no screws showing) and also says that it fits 58'-73'. Other sites I have seen state 72'-77' on their fuel pumps. Was there a change in 1971? Seems to me if the bolt holes were lower in the block it would fit perfectly.
Do I need a different fuel pump? Turn the engine to find it on a "sweet spot"? Can I take out the spring without it affecting performance? Or is that why I was getting low pressure? Anyone know what pressure it is supposed to be at idle/under load?
New fuel pump looks identical to the old but doesn't go into the block far enough to bolt in. The small spring on the old pump was broken (two pieces laying inside the arm) and I'm assuming the spring on the new one is keeping it from going in. According to Spectre, 58'-73' are all the same. Cruiser Corps sells a simpler-looking pump (smaller and no screws showing) and also says that it fits 58'-73'. Other sites I have seen state 72'-77' on their fuel pumps. Was there a change in 1971? Seems to me if the bolt holes were lower in the block it would fit perfectly.
Do I need a different fuel pump? Turn the engine to find it on a "sweet spot"? Can I take out the spring without it affecting performance? Or is that why I was getting low pressure? Anyone know what pressure it is supposed to be at idle/under load?
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