| Author |
Message |
C. Ray Powell (Raypowell) (152.163.188.227)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 04, 2002 - 9:22 pm: | |
I have a Detroit Diesel. What is the function of the Fuel Pressure Switch?
Thanks
C Ray |
Jim Ashworth (Jimnh) (172.148.16.232)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 04, 2002 - 9:42 pm: | |
This cuts out the starter motor after there is fuel pressure, which means the engine is running. It also makes it so that the engine shutdown can be overridden by pushing the starter button on the MCI's. In my experience, they are not the most reliable switches and are frequently bypassed.
Jim |
Luke Bonagura (Lukeatuscoach) (12.90.2.118)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 04, 2002 - 9:55 pm: | |
Hi C Ray:
Do yourself a favor and eliminate it.
Take the wire off of the sender and GROUND it to
the engine or body which ever is convenient.
You will have one less thing to go wrong.
When we were operating buses, we eliminated every one of them.
In a big fleet operation, they might prove important although I could never figure out WHY???
For the converted coach owner, in my opinion, the less GREMLIN producers, the BETTER!!!!
Just my thoughts on the question.
LUKE at US COACH |
jmaxwell (66.42.92.13)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 05, 2002 - 1:43 am: | |
My Grumman 6v92 w/730 trans had (notice I say HAD) two. One to protect the starter and the other to prevent shifting from N - D above idle. Both failed, were hard to find replacements locally, and therefore were eliminated. Don't need to be stuck because of some cheap part going South. I have yet to reason the starter one; like who can't hear the damn engine running. |
Tim Christofferson (Tcmc8) (205.118.9.15)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 05, 2002 - 1:51 pm: | |
When I start my MC-8 (8V71) the engine will fire and turn over immediatly, however the oil pressure will not immediately come up. If I release the starter switch the automatic shutoff will activate because the oil pressure is still low. If I hold the start switch on to prevent the automatic shut-down, the fuel pressure switch will activate and shut-off of the starter motor.
If you disconnect the fuel pressure switch from this circut, you run the risk of burning up the starter motor before you get sufficent oil pressure to release the starter switch.
Also, as already mentioned, if you over heat the engine enough to cause automatic shut down, you can hold the start switch on to to overide the automatic shut down and move the bus off of the road. If the fuel pressure shut off does not turn off the starter moter under this condition your starter motor will probably be toast. |
joe shelton (Littlewind) (67.241.228.178)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 18, 2002 - 10:19 am: | |
I broke the pressure switch when moving the fuel filters and did have a bit of a prob finding replacement. While wiating for one to arive, I wired it to ground via a switch. I then would start from the rear and close the switch when I thought I had fuel pressure. I agree that I could clearly hear the engine running when it started. But when starting from the rear I could also clearely hear when the starter motor disengaged when I closed the switch.
So dosen't this mean I'm saving wear on my starter when using the pressure switch?
Joe |
tcmc8 (205.118.9.14)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 19, 2002 - 9:50 am: | |
That is the point, Joe. As soon as the engine is turning fast enough to start (fuel pressure is generated) the switch turns off the starter motor. |