Help with 502 Mag
#1
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Having problem with my 502 mag dying after being run for 20-30 minutes. Dies and just will crank with a little spitting and sputtering. Let it sit and cool off for a few hours it fires right back up just fine. Any ideas?
#2
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Sounds like vapor lock. These motors are notorious for vapor lock especially with the VST system, but will also do it on the cool fuel 502's.
Do a search on here and you'll find a bunch of topics.
Do a search on here and you'll find a bunch of topics.
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#3
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Many of us have/had same problem on 502 MPI's. I went the Merc route and installed their add-on pump. It worked really well, and I never had the issue again (you can install this yourself easily). Others have run return lines back to tank, installed better pumps, etc. Many ways to skin a cat.
#8
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Mechanical pump feeds the electric fuel pump inside the VST located above# 7 cylinder. Unless your carb 502 mag.