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1750 GTV US specs 1969
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Discussion Starter #1
Hi all. Wondering if a buzzing sound of the fuel pump is normal. Since the 1st day i’ve the car sound is the same I also have the red light on on the dash (next to the brake test push button ).
car runs ok but cold start are tough. Thanks
 

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Having the low fuel pressure warning light constantly illuminated is not normal and should be dealt with. I would start with the filters, both front and rear. After the light is acting normally, then see if there is anything up with your pump.

Cheers,
 

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I'm not familiar withe the 1750 warning lights but if it is as the previous poster...do not drive the car..go immediately to change the REAR after tank fuel filter. It has sediment in it beyond what you might think is possible especially if your fuel tank has sediment in it from long periods of storage.. Common in old sports cars. Inspect your tank by removing the fuel level sender and if you can't see anything , dangle a parts magnet to the bottom and fish around. It should come up clean... A clogged or restricted filter will cause your fuel pump to growl and wheeze.. It should be happy and hum a very even tune
 

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Discussion Starter #4
Thanks all. Actually the tank is new so is the first filter..I have put a link so that you can check on the sound.(we can clearly hear the buzzing sound but also some small"cracking ones" Should I still open the tank and check for sediments of stuff like that?
thanks IMG_8502.MOV
 

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Thanks all. Actually the tank is new so is the first filter..I have put a link so that you can check on the sound.(we can clearly hear the buzzing sound but also some small"cracking ones" Should I still open the tank and check for sediments of stuff like that?
thanks IMG_8502.MOV
Backtracking tells me you had to replace a dirty tank and the new one should be fine. The question is how much crud did the pump ingest before you changed the tank. Did you change the front filter and inspect it? The pump has pretty tight tolerances and might clear itself if there are some restrictions IMHO. I had a very dirty rear filter and low pressure light after driving for like 150 miles and the pump was grouchy and intermittent sounds and the tank had been changed before I got the car but remarkable the retro techs who changed the tank didn't change any of the filters as the rear filter had a vendor sticker who has been out of business for decades. I would check the front filter next to take that question out of the loop. If the light stays on the pump then has to be suspect. The light is the critical red flag. If it stays on steady your car will bog down and slow to a halt. I limped home from a 150 mile trip having to stop 4 or 5 times for 10 or so minutes each time the last 90 miles to cool off a restricted pump before getting back down the road and finally coasting into my drive way. Once I changed the two filters everything was bliss and the light remains off ith only a wink on cold start up.. the way it should be and the pump is happy..You might also want to do the bare hand test on the pump to see if it is excessively warm. It shouldn't be.
 

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Discussion Starter #6
That is so precious as i fo. Thank you Divotandtralee. I am waiting to hear form the guy who I got the car from to hear what he changed as fuel related parts. I know that he changed the tank filter so that one is new., The pump indeed might have ingested many stuff before tank and filter were changed. I will do the hand test on the pump.The from filter might not have been changed, I will check that too. Question can I do the hand test just by switching on the pump and let it runs but without starting the engine? Again thanks for precious info.
 

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Hand test ..yes... The front filter really is not as critical if the rear filter is changed regularly and is doing it's job. The front one is more like a double prophylactic. If you have never done it I highly recommend removing the entire filter assembly ...much easier and effective getting the seal lined up in the long run. It's pretty darned simple.. One last item sharpie the date and mileage on the rear filter just so you know.
 

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The pump will run with the ignition in the “on” position, so no, you don’t need to start the engine...
Have you driven the car and if so, does it hesitate or stall? If not your fuel pressure may be fine but the fuel pressure sender may be bad or disconnected. Have you checked the wire and terminal to the sender on top of the front filter?
 

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Discussion Starter #9
Hand test ..yes... The front filter really is not as critical if the rear filter is changed regularly and is doing it's job. The front one is more like a double prophylactic. If you have never done it I highly recommend removing the entire filter assembly ...much easier and effective getting the seal lined up in the long run. It's pretty darned simple.. One last item sharpie the date and mileage on the rear filter just so you know.
I am wiating to get info form the guy who worked on the car regarding the front filter. Thanks for the "sharpie" tip!
 

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Discussion Starter #10
The pump will run with the ignition in the “on” position, so no, you don’t need to start the engine...
Have you driven the car and if so, does it hesitate or stall? If not your fuel pressure may be fine but the fuel pressure sender may be bad or disconnected. Have you checked the wire and terminal to the sender on top of the front filter?
Ok, will do the hand test. Also how easy is it to remove the Spica box (air)? in order to have direct access to the sensor? Or can I access it easily? I can do some mechanical work but I am not a pro...thanks
 

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Ok, will do the hand test. Also how easy is it to remove the Spica box (air)? in order to have direct access to the sensor? Or can I access it easily? I can do some mechanical work but I am not a pro...thanks
You should be able to see the fuel pressure sender without removing the air box. An inspection mirror comes in handy if you have one.
Removing the air box only takes a minute or two. Just loosen the two straps, four large intake hose clamps (between the box and intake manifold), one small idle air hose at the top, and one hose clamp to the oil vapor separator. Then wiggle the air box free to pull it out.
 

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Ken is correct ... two 10mm nuts on the straps engine side.. small hose top of center to idle nipple .... 4 intake hose clamps loosed engine side.. oilseparator hos under the front of filter can be testy . Then wiggle wiggle wiggle toward you Patience and care wins the day. don't get frustrated... You can't screw up anything
 

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When I hear the sound you describe coming from the fuel pump in one of my Alfas I know it is time to replace the pump. It is almost like the manufacturer designed it that way.
 

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Ken is correct ... two 10mm nuts on the straps engine side.. small hose top of center to idle nipple .... 4 intake hose clamps loosed engine side.. oilseparator hos under the front of filter can be testy . Then wiggle wiggle wiggle toward you Patience and care wins the day. don't get frustrated... You can't screw up anything
Reinstalling is just reversing the procedure and requires lining up the hose connections and wiggling it back in place. But if your box has the two vinyl hose drain lines hanging from the bottom, make sure they are clear of the SPICA long rod, and the throttle linkage works unimpeded. If not, and the drain hoses are old and hard, they can interfere with the linkage causing unintended WOT (aske me how I know...).
 

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Discussion Starter #15
Merci to all. Will continue to work on all this and keep you posted.
Step 1had test on the pump
'Step 2, will check the front filter
step 3 will check fuel pressure sensor
thanks

To answer to Bellagt, the car runs fine but , I have to really push the gas pedal to accelerate (normal I guess). Does no rattle when warm.
 

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Discussion Starter #16
Reinstalling is just reversing the procedure and requires lining up the hose connections and wiggling it back in place. But if your box has the two vinyl hose drain lines hanging from the bottom, make sure they are clear of the SPICA long rod, and the throttle linkage works unimpeded. If not, and the drain hoses are old and hard, they can interfere with the linkage causing unintended WOT (aske me how I know...).
Ok, will pay attention, very carefully.
 

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Hope that all goes well. It would take you less time to just change the front filter than to wait to hear if someone has previously done it. If there is a parts place near you that carries Baldwin filters it should be available and not expensive, a PF866 (since you have an early car). The rear filter from napa is a 33299 (3299) and is dirt cheap, you should buy like 3, just to have around.
Does your light come on simultaneously with the key? Or a few heartbeats after? If it's simultaneously I would use a multimeter in Ohms setting with the wire disconnected and see if the pressure switch is stuck. The loose wire in free air should have a light on or off and the wire grounded should be the opposite. Double check the ground you are using is actually a ground.... Take the airbox out, it's super easy, a good first job.
Your first priority at this point should be getting the light working correctly.

Cheers,
 

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Discussion Starter #18
Hope that all goes well. It would take you less time to just change the front filter than to wait to hear if someone has previously done it. If there is a parts place near you that carries Baldwin filters it should be available and not expensive, a PF866 (since you have an early car). The rear filter from napa is a 33299 (3299) and is dirt cheap, you should buy like 3, just to have around.
Does your light come on simultaneously with the key? Or a few heartbeats after? If it's simultaneously I would use a multimeter in Ohms setting with the wire disconnected and see if the pressure switch is stuck. The loose wire in free air should have a light on or off and the wire grounded should be the opposite. Double check the ground you are using is actually a ground.... Take the airbox out, it's super easy, a good first job.
Your first priority at this point should be getting the light working correctly.

Cheers,
Thanks. the light is on as soon as I turn the ignition on ( not even starting the engine). Will also do the electrical test and report... looks like my week end s going to be busy..cheers
 
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