78 240 Vibrating Fuel Filter!? Wierd
#1
10-12-2011, 05:14 PM
Join Date: May 2007
Location:
Posts: 185
Likes: 0
Received 0 Likes
on
0 Posts
78 240 Vibrating Fuel Filter!? Wierd
So, I just put a new fuel pump in my 78 ( thought thats why it wouldnt start , intermittently) Turns out the fuse was corroded... 
New pump, car started up great ( didnt find the fuse till later) BUT, the Fuel filter ( new one) is vibrating like you wouldn't believe! I isolated the source of the source of the vibes as def the filter, and nothing else ( the hard and soft lines vibrate, but not as bad, and less vibes the farther away form the filter you get. Additionally, the main pump under the car does feel like it could be A source of vibrations, but not as much as the filter itself.
Additionally, With the new pump the car idles great, but will hiccup and hesitated while adding throttle, while driving, like its loosing fuel. I thought low pressure at first, but after popping off some fuel lines and having them shoot fuel non stop for several minutes, its clear that at least the tank itself is FULL of pressure. Weird.
Ive checked the relay, looks fine. Im about to try another new filter, then from there, reinstall the old pump, and see what happens.
*********update........... Went to put the old pump back in, found that the yellow wire that screws to the housing, aka the ground i assume, had somehow come loose ( the screw is sitting at the bottom of my gas tank. So... Pretty freeking wierd, how did it run at all?
The buzzing is still in full annoying effect, but after a spirited test run, it doesn't seem to be hesitating ( just once or twice, almost un noticeably in a 5 min drive )
********** Update #2... Put the old pump back in. No buzzing, no vibrations, car runs just great.
So, someone help me understand the pump system and how it works, and what in the world the difference between these 2 bosch pumps. I understand the the PSI may be different between the 2, but arent the "in tank" pumps just supposed to be "helpers" ( low psi, hi volume ) Vs the main pump being High PSI and low volume? Could it be that these 2 pumps are just mot acting in unison with one another, creating some sort of harmonic vibration? ( I just made that up
I would love to put the new pump back in, But not until I have some positive ideas on how to kick the buzzing down.
Thanks for any help!
New pump, car started up great ( didnt find the fuse till later) BUT, the Fuel filter ( new one) is vibrating like you wouldn't believe! I isolated the source of the source of the vibes as def the filter, and nothing else ( the hard and soft lines vibrate, but not as bad, and less vibes the farther away form the filter you get. Additionally, the main pump under the car does feel like it could be A source of vibrations, but not as much as the filter itself.
Additionally, With the new pump the car idles great, but will hiccup and hesitated while adding throttle, while driving, like its loosing fuel. I thought low pressure at first, but after popping off some fuel lines and having them shoot fuel non stop for several minutes, its clear that at least the tank itself is FULL of pressure. Weird.
Ive checked the relay, looks fine. Im about to try another new filter, then from there, reinstall the old pump, and see what happens.
*********update........... Went to put the old pump back in, found that the yellow wire that screws to the housing, aka the ground i assume, had somehow come loose ( the screw is sitting at the bottom of my gas tank. So... Pretty freeking wierd, how did it run at all?
The buzzing is still in full annoying effect, but after a spirited test run, it doesn't seem to be hesitating ( just once or twice, almost un noticeably in a 5 min drive )
********** Update #2... Put the old pump back in. No buzzing, no vibrations, car runs just great.
So, someone help me understand the pump system and how it works, and what in the world the difference between these 2 bosch pumps. I understand the the PSI may be different between the 2, but arent the "in tank" pumps just supposed to be "helpers" ( low psi, hi volume ) Vs the main pump being High PSI and low volume? Could it be that these 2 pumps are just mot acting in unison with one another, creating some sort of harmonic vibration? ( I just made that up
I would love to put the new pump back in, But not until I have some positive ideas on how to kick the buzzing down.
Thanks for any help!
Last edited by endneu913; 10-12-2011 at 07:26 PM. Reason: update
#2
10-12-2011, 11:02 PM
Super Moderator
Thread
Thread Starter
Forum
Replies
Last Post
timoc663
Volvo 240, 740 & 940
5
08-14-2016 05:35 PM
