Fuel pump question

[Michael]

So I took my car out for a spring shakedown cruise last week. I ran it for a few hours with ac on which of course blows hot air on the fuel pump area. After getting home the pump was singing a song of woe. The engine ran fine. So, is the pump on it's way out when it makes noise or is this a normal symptom of a pump that just got too hot? Keep in mind it was very hot that day and the engine still ran fine. I have a spare pump I can replace with or shall I get a hot air dam? Or both?
OE pump btw, not the new ones. Not sold on those quite yet.

[Christian Dietrich]

Did it sound like the bearings in the motor for the pump for the impeller? Its possible that the fuel pump can be going out if it's starting to sound like that when it's really hot outside. I have a piece of heavy-duty rubber I got some work that I want to install directly behind the fans so it blocks the air going across the gas tank. I seen Hervey has something like that also. The new fuel pumps that you can get from DMC good and mine is been in my car now for 2 years without any issues at all and it's a really simple install. I know they had issues with them before but even on days when it's been crazy hot outside and everything I've never had an issue once. Was it like a whining sound that you were hearing?

Sent from my SM-N920P using Tapatalk

[Michael]

Did it sound like the bearings in the motor for the pump for the impeller? Its possible that the fuel pump can be going out if it's starting to sound like that when it's really hot outside. I have a piece of heavy-duty rubber I got some work that I want to install directly behind the fans so it blocks the air going across the gas tank. I seen Hervey has something like that also. The new fuel pumps that you can get from DMC good and mine is been in my car now for 2 years without any issues at all and it's a really simple install. I know they had issues with them before but even on days when it's been crazy hot outside and everything I've never had an issue once. Was it like a whining sound that you were hearing?

Sent from my SM-N920P using Tapatalk
It was more of a loud groan, changing pitch at times. I started it up again after it cooled and it's fine. Like I said I have a brand new pump I can install but if this is just a normal reaction of one that's got too hot then there is no point in changing it and I will just get a deflector(and if Hervey is the only vendor that offers them, I will make my own).

[Christian Dietrich]

My best friend has a stock fuel pump in his DeLorean and I've never heard any noises with his but I wonder with the change of the temperature of the fuel if the pickup hose from the screen to the pump started to collapse causing the fuel pump too groan and work harder? If you do go in there and investigate you probably should also check that pick up hose or replace it! That's one thing I do not like about the original stock fuel pump is a way that hose sits in there all angled and twisted and I always thought that was an Achilles heel to the fuel system
It was more of a loud groan, changing pitch at times. I started it up again after it cooled and it's fine. Like I said I have a brand new pump I can install but if this is just a normal reaction of one that's got too hot then there is no point in changing it and I will just get a deflector(and if Hervey is the only vendor that offers them, I will make my own).

Sent from my SM-N920P using Tapatalk

[dn010]

I've been running OE style "Hayg orig" 909 fuel pumps in my D ($50 on eBay). I replaced the first operational one with a new one because I used the first to get a Volvo running and was afraid I had damaged it - it still works and now rests as a spare in my trunk. Anyway, this pump seems to make a random groan while cold, hot etc. and it has for years now but its never let me down with the Florida heat. I can try taking a video of the noise if you want to compare.

Every OE style pump I've run has made noise ever since I've owned the car 16 years ago, it has just come to be something I've accepted as normal.

[Michael]

My best friend has a stock fuel pump in his DeLorean and I've never heard any noises with his but I wonder with the change of the temperature of the fuel if the pickup hose from the screen to the pump started to collapse causing the fuel pump too groan and work harder? If you do go in there and investigate you probably should also check that pick up hose or replace it! That's one thing I do not like about the original stock fuel pump is a way that hose sits in there all angled and twisted and I always thought that was an Achilles heel to the fuel system

Sent from my SM-N920P using Tapatalk
I forgot about the possibility of the pickup hose collapsing. I never did the spring mod. Maybe next tine I have it out I will pit in a piece of fuel hose not made of paper thin latex rubber.

[FABombjoy]

I had the air dam, Grady's improved pickup hose, and a pump with only 15k miles. Any time the heat index went above 90 that thing would howl. I pulled the original assembly out and the tank & pickup screen was spotless and pickup. No signs of collapse or kinked pickup hose. Ads for air dams/heat shields go back to 1986 in DeLorean World so it just seems that the OEM pump is crappy and cannot handle heat.

56626

The all-in-one module is dead silent. Other than the lack of key-on fuel level, I have no complaints. Eventually I'll fix that, too.

[hippieman9]

I have noticed that after a good day of driving my fuel pump whines too. Its a high pitched whine. If I stop and fill up with fuel the while goes away. I assume due to cool fuel in the tank cooling down the components. I like the idea of switching to the new style integrated fuel pump. I know I'd rather replace it once then have to worry about it when on a trip or something.

[DARCOM]

My pump did this and what helped a bit was to make sure the return fuel line inside the tank sprays on to the fuel pump.

[Christian Dietrich]

Yeah its really not the best design.
I forgot about the possibility of the pickup hose collapsing. I never did the spring mod. Maybe next tine I have it out I will pit in a piece of fuel hose not made of paper thin latex rubber.

Sent from my SM-N920P using Tapatalk

[dn010]

It's the material of the original hose that is terrible. If you have the soft rubber original hose then do yourself a favor and get it out. I've been running the hardened version (I think it was one Rob Grady sold but I can't remember) of the pump to pickup hose for a decade and it has been trouble free. The biggest issue I ever have is the damn fuel pump boot breaking down with today's ethanol fuel. I bought one new and it lasted less than a week, I bought another used here on the forum and it's lasted years and still going so it's really a crapshoot.

Not the best design, agreed, but I'm also not sold on the all-in-one units yet.

[Bitsyncmaster]

I had the fuel pump buzzing after the gas got hot and I had the spring installed and Hervey's hot air dam. It was only after I installed a fuel cooler it stopped. That was before DMCH offered the new pump.

[David T]

If the pump ever makes that noise you have damaged it and it will make that noise quicker and quicker even when the fuel does not get hot. Eventually the pump will fail. The spring helps but doesn't prevent it. If DMCH can ever perfect the newer style all-in-one unit that would be the way to go. The OEM set-up is jut too Rube Goldberg.

[Michael]

I had the fuel pump buzzing after the gas got hot and I had the spring installed and Hervey's hot air dam. It was only after I installed a fuel cooler it stopped. That was before DMCH offered the new pump.

I don't think I have seen one of those. Is that a DMC specific part or a universal?

[Bitsyncmaster]

I don't think I have seen one of those. Is that a DMC specific part or a universal?

The old pump that buzzed was a DMCH part. It was what they found to replace the NOS pumps.

There new pump is different and includes the fuel level sender.

[Michael]

The old pump that buzzed was a DMCH part. It was what they found to replace the NOS pumps.

There new pump is different and includes the fuel level sender.

I was talking about the fuel cooler

[Bitsyncmaster]

I was talking about the fuel cooler

My own design.

[SS Spoiler]

That"s pretty cool....

[Michael]

That"s pretty cool....

ing!