Fuel Pump tick/knock
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Joined: Mar 2016
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Fuel Pump tick/knock
I have noticed a concerning tick/knock from the bottom end on the #2 cylinder side, very concerning. The engine is low miles so no real reason for there to be an issue but I remember replacing the fuel pump 3 months ago chasing a vapor lock issue. No issues or noise until just recently after about a 1000 miles on the fuel pump. Do these fuel pumps fail like this? Prefer this over the other possibilities.
Melting Slicks
Joined: Apr 2021
Posts: 2,672
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From: Minnesota
You can remove the pump and run the engine for a while with the fuel in the float bowls. This will tell you if the noise you’re hearing is the fuel pump or not.
I would also remove the fuel pump rod and check it for any abnormal wear.
I would also remove the fuel pump rod and check it for any abnormal wear.
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Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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I've never seen a fuel pump fail like this. However, it's possible you have a inferior pump rod or have worn the lobe on the cam that drives it.
Pain in the butt to unbolt the fuel pump. But do it and pull out that pushrod.
As above, start engine on what fuel is left in the float bowl. You should know in seconds if the knock is gone.
Pain in the butt to unbolt the fuel pump. But do it and pull out that pushrod.
As above, start engine on what fuel is left in the float bowl. You should know in seconds if the knock is gone.
Pro
Joined: Jan 2004
Posts: 649
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From: TX
It's supposed to direct some hot exhaust air up to the divorced choke on older C3 carbs and intake manifold but they can sometimes get stuck due to rust. Spacer is probably the cleanest approach but some people 'wire' these things open too.
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Melting Slicks
Joined: Apr 2021
Posts: 2,672
Likes: 2,124
From: Minnesota
Might be the cold weather too.
With headers (no heat riser) and an electric choke I’d say it takes about 5 minutes to warm up after a cold start. Starts up and runs great instantly though.
With headers (no heat riser) and an electric choke I’d say it takes about 5 minutes to warm up after a cold start. Starts up and runs great instantly though.