98 454 Mag Mpi mid range missfire
05-10-2019, 04:31 PM
#21
Registered
iTrader: (1)
There is usually a tiny screen under the regulator in most fuel rails. I'd check there 1st. if clogged, the fuel will be deadheaded and will be at fuel pump deadhead psi.
Ck diagram to see it has 1 before you go in.
Ck diagram to see it has 1 before you go in.
05-11-2019, 07:23 AM
#22
Registered
iTrader: (1)
I would suspect that the problem is the regulator and or screen (item 16) on the cool fuel module (item 15).
98 454 Mag Mpi mid range missfire
The upper one is another regulator (item 5) but is used as a damper, and there is no fuel return from the rail its plugged (item 11)
https://www.mercruiserparts.com/bam/.../31798/2690/90
98 454 Mag Mpi mid range missfire
The upper one is another regulator (item 5) but is used as a damper, and there is no fuel return from the rail its plugged (item 11)
https://www.mercruiserparts.com/bam/.../31798/2690/90
05-11-2019, 12:17 PM
#25
Platinum Member
Platinum Member
iTrader: (6)
You have 2X the pressure needed, if its that high the injectors wont fire correctly
05-11-2019, 10:26 PM
#28
Registered
05-12-2019, 06:44 AM
#29
Registered
iTrader: (1)
Applied vacuum to this and it doesn’t open is this a valid test and I’m assuming this would cause my excessive fuel pressure.
Need an air source, gauge and pressure regulator. Apply air pressure to the larger hole in your first pic. Slowly increase the pressure and the regulator should open around 43 psi.
05-12-2019, 10:53 AM
#30
Registered
Thread Starter
Join Date: May 2019
Posts: 24
Likes: 0
Received 0 Likes
on
0 Posts
got it tested with a regulator it opens at 42psi every time guess I’ll pull the regulator on the rail and test that one .
