Hi

My new aeromotive electric fuel pump burned out and they say it is because of my 10 micron (stock) sock filter that is in the tank.

Soooooo can I just remove the sending unit out the bottom and get the sock off of it and put the unit back in without it?

Never been in the tank but by looking at the threads on the subject it seems basic and easy with the right tool

Of course my tank is full

BTW even though they said it was my fault that they would warranty it one time.

Thanks in advance

Doug

 

sure, take the sock off, but you might want to put an inline filter somewhere after it.
Bill

 

They make a 100 micron screw on filter inline and then recommend a 40 or 10 before the carb

Thanks for the info

Doug

 

Yes, you can take the sock off.

A brass drift will do the job if you don't have the special tool.

Where did the 10 micron number for the sock come from? That seems awfully small - 1/10th the size of a hair. Are the fuel pump guys trying to pass the buck? Chevy doesn't even refer to it as a "filter", they call it a "strainer".

 

I was looking in a old 63 build manual and it said it was a 10 micron filter.

They said it made the pump work to hard.

All I know is I ran a Holley electric pump for years with no hassle. I thought I was making a move up.

Maybe it was for the fuel injection units of the early years and possibly they just stuck with it. Maybe John Z will step in with the scoop on the sock.

Doug

 

I've never seen a spec on the "strainer" (sock), but I doubt seriously if it's anywhere near as fine as 10 microns. There was no special sock for F.I. cars - all cars used the same fuel sender/sock assembly, regardless of the engine. If there's a lot of old gas varnish on the sock, it would significantly restrict flow.

 

At 10 micron with CAM 2, you will start collecting upper cylinder lubricants. We found this our the hard way with a mud drag race truck we built a few years ago. Had to go to 30 micron to let the fuel through.

 

do u have a return line?
makes an e-pump work less.
have u tested the output? strainer may be ok? test it!

 

I agree with how you think and neither would I believe that a sock filter would be as fine as 10 microns. My tank is spotless with a new sock but the trapped upper lubricant problem could be very well be coming into play. However just for shared information on page 6M35 of the 63 shop manual it states very clearly that the sock is a 10 micron filter

RGS has brought up a point that a few people have found out the hard way and that includes one funny car whose crew chief did not think it was quite so funny when their filter was clogged on race day. I had heard this before about the 10 micron filters trapping the upper end lubricants found in race gas and that could have contributed to my problem because I fed my old motor a steady diet that included CAM2 mixed in the tank.

In my neighborhood 110 CAM2 is a dollar a gallon cheaper than 100 PEP Boy Gas so it always seemed a no brainer to me to use the better and cheaper gas. I had no idea that I had such a fine filter installed and it could very well be gooked up through ignorance. That part I will find out tomorrow as today was spent getting the full tank empty and dropping the broken pump and spare tire carrier down. I now have the only Town Car around that gets its gas from a vette.

Unless it is really gooked up IMO a mechanical pump should not have a problem but with an electric pump having to suck gas like us trying to drink through coffee straws wont work either so the pump burned out. Fortunately they are going to warranty it and they now have a heads up on corvette sock filters.

Doug

 

For reference.

 

\

Hi Matt

Thank you for your reply

There is no return line and to me when I see the fuel flow as coming out of the tank it seems to be more than sufficient to me. However when on full demand such as a dyno pull this motor burns 1 galleon in 20 seconds

When on the dyno the builder had the same regulator as me but a separate AN 6 line for each bowl. In place of that I have one AN8 line from the regulator then going into a fuel log with AN8 inlets and outlets.

The pump has 3/8 fittings but I am going to remove the 3/8 custom line added to the now "sockless" 3/8 in tank line and replace the external 3/8 lines with AN8 lines and a 100 micron inline filter attached to the pump for what I hope will have some sort of fuel log reservoir effect. Also somewhere between the pump and carburetor I will use a 40 micron inline in place of a 10 that I already have because of the CAM2 issue.

This system meets their approval and I will overnight the pump back to them today and hope for a quick return.

Doug

 

That reference is to the filter at the input of the fuel injection fuel meter, not the sock in the fuel tank.

 

Doug
how many amps does it draw?
does it get hot?

 

Hi John

Well I certainly consider your knowledge and expertise above my lack of it in all things pertaining to corvettes I guess I will just have to look at it again when I return the tool I borrowed to get the sending unit out. I had originally thought because of the year that it had something to do with FI units but then the owner of manual and of a Corvette repair shop said it was in the tank. So thanks for pointing that out and I will take it up with him when I stop by there tomorrow......... especially since Aeromotive Inc has now been told (first by the repair shop) that there is a 10 micron filter in all midyears

Regardless of what the sock is there was still on my system a 10 micron filter before the pump as a result of my error in understanding how filtration is measured :o Although it was not exposed to any CAM2 it is a canister type and cannot supply fuel fast enough for the pump that it was right next to......... my bad, my red face.

Matt asked
.

Well it was certainly on the warm side when it quit on me....... it is only suppose to draw 5 amps and I have a 10 amp fuse inline (although they call for 15) that did not blow. When I would turn it on you could hear it spinning but very quietly..... as if the impeller was wasted. I sent it out this morning and I am about to change clothes and figure out some stuff I need to put it back together with 8AN.

Doug

 

Doug
as 1 failed
i suggest
a ~1.2 ohm resistor in series(a coil ballast often will do) min 25w.
test it to see if it keeps up WOT
if not, a min. 5A microswitch at the carb can be set to bypass the R past 1/2 throttle.
pump will stay cool, draw 2 1/2a, be quieter and last 2-4x longer.

 

To much risk their bro......... if it failed i burn my motor. That was made very clear to me by the builder. I thought he was a tad **** over the fuel supply issue but he says if that motor goes lean at 7000 something bad will happen real quick

Anyway the sock is off and the sending unit is back in. One thing bothers me though. I was able to drain it dry so I figure with the quart or two of gas in a can I would pour it back in the tank and make sure there are no leaks before moving on. No leaks but no gas coming out of the tube either..... what gives? I can see a fair amount a gas in the tank, like an inch or so and I jacked up the front end just to make sure but why is it not coming out?

Doug

 

While the pick up end of the fuel line is quite close to the bottom of the tank, the line itself goes up a ways before bending down to exit the tank. The pick up end is towards the front of the tank. Put a suction on the line coming out of the tank and flow will commence.

 

Thanks nassau66427

I understand that and I am going to assume that I can do that later and just be happy for now that the sending unit is not leaking. I have had enough of the taste of gas yesterday and today to last for awhile......hate to get addicted to it LOL

I am going to finish the plumbing up and then see if the pump will do that for me.

Doug

 

then i'd skip the test and use 2 microswitches. they are only $1 each.
but i suspect u will likely wait until the 2nd pump fails, and when it does, u have the solution for #3

 

It also comes in handy that blowing (low pressure, of couse) the gas back into the tank will allow work on the lines without leaks.