Fuel Pump Check Valve
Thread Starter
Safety Car
Joined: Feb 2006
Posts: 4,545
Likes: 387
From: Fort Worth Texas
Fuel Pump Check Valve
Hey guys I have a new to me blown 08 coupe with a Maggie MP112. I think it has a Walbro fuel pump. If I start the car as one normally would, it turns over too long before starting. However, if I prime it first by holding the start button 5 secs prior to engaging clutch, it starts perfect every time. It has a Magnavolt booster as well. Is this the fuel pump check valve failing? Thanks for any help.
Pro
Joined: Jan 2012
Posts: 580
Likes: 15
i have the exact same problem with my aftermarket racetronix pumps... I put a checkvalve on my order when I placed it, but racetronix removed it from the order stating that their pumps hold prime... They were wrong... sounds like quite-a-few companies aftermarket pumps have this problem... I'm gonna add a check valve to my fuel system someday down the road, sick of it taking 2-3 times to crank....
have heard that some aftermarket fuel injectors or lack of proper o-ring sealing at fuel rails can make this problem worse....
have heard that some aftermarket fuel injectors or lack of proper o-ring sealing at fuel rails can make this problem worse....
Safety Car
Joined: Nov 2007
Posts: 4,436
Likes: 875
From: Bay Area CA
Hey guys I have a new to me blown 08 coupe with a Maggie MP112. I think it has a Walbro fuel pump. If I start the car as one normally would, it turns over too long before starting. However, if I prime it first by holding the start button 5 secs prior to engaging clutch, it starts perfect every time. It has a Magnavolt booster as well. Is this the fuel pump check valve failing? Thanks for any help.
I had the same issue, if I held the start button down for a few seconds the car would start up. Once started, the car ran fine. When I shut down the engine while in my garage (all quiet) I actually heard the fuel drip back into the fuel tank (1/2 tank or less of fuel). It sounded like the car was taking a ****. This would be a good indication that the check valve failed. I replaced the fuel pump and all is good!
Last edited by Mike's LS3; Sep 30, 2017 at 12:25 PM.
Team Owner
Joined: Nov 2007
Posts: 24,035
Likes: 2,342
From: Gilbert AZ
It isn't a pump issue as much as the siphon setup bleeds off. Just part of the Corvette fuel system. Adding a check valve doesn't really help because it still bleeds down though the jet siphon
Le Mans Master
Joined: Jan 2009
Posts: 5,656
Likes: 112
From: ocean springs mississippi
So,my car sits for weeks at a time....would I have to prime pumps every time (walbro pump)?
