Fuel filter location?

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Valkman

Valkman

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I just bought a car with a Holley streetmaster carb and it has a lot of hesitation when you get on it. I happen to notice that someone mounted the fuel filter before the mechical pump. Would this cause a problem with fuel flow?
 
Your accelerator pump could be out of adjustment or your nozzle is too small/big. There's also cams you can change to alter the flow rate. Check out this video...
 
I placed a small fuel filter in front of the pump years ago when I was getting some crud out of the fuel tank that I thought might have damaged a few fuel pumps. After that, I did not lose another pump, and I did not notice a power problem. Once I replaced the tank, I got rid of the extra filter.
 
I have a canister filter by the tank and one in the line to the carb, no issues at all.
 
I watch the video, thanks for posting it, but I my problem is not with the initial throttle, normal driving it's fine it's when get in the into it that it falls flat then picks back in abit but the secondaries nevr seem to kick in. That’s why I was thinking maybe it's get starved for fuel
 
Well the car has just recently restored (not by me) and the filter looks new.
 
Valkman said:
I watch the video, thanks for posting it, but I my problem is not with the initial throttle, normal driving it's fine it's when get in the into it that it falls flat then picks back in abit but the secondaries nevr seem to kick in. That’s why I was thinking maybe it's get starved for fuel
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Hang on,
The secondaries are coming in too far and too fast. The proof is in what you are feeling. The "falls flat" is the kick in the nuts of secondaries coming in too quick. And the "never seem to kick in" is cuz they're now wide open!
Easy solution just slow 'em down until it stops falling flat.

On the off chance that you have a DP carb, or one way too big for your combo, the above applies to carbs of 650s to 850s, with Vacuum secondaries or Air valve secondaries, like; AVSs,AFBs,TQs, Holleys, and copycats.
 
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Do you think, how can I check for this? I know very little about vacuum secondary Holleys
 
I think I'll swap out a street demon carb I have on another car that I know works well and see if the problem goes away before l start messing with this Holley carb. By the way this is a vacuum secondary street master on a 340 with a pretty hot cam so I'm not to sure it's over carbed?.

The u joint broke on me today and I had to have the car towed to a shop, so I'll give a closer look when I get it back.
 
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Well I put a Eddy 750 AFB I had lying around, and problem solved! It runs smoother with no hesitation. I guess the Holley needs some work?
 
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Might depend on the condition of your tank. When I got my car , fresh rebuild, new fuel filter. 5 miles filter plugged. New filter , plugged again. 3rd filter plugged, fuel pump plugged so bad lever was inoperable. Tank was totally beyond salvage, replaced . If your tank has issues but not too bad a filter before the pump is a good idea but it would be preferable after the pump in most instances.
Yote
 
halifaxhops said:
I have a canister filter by the tank and one in the line to the carb, no issues at all.
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This is the way my Barracuda is set up also. I have a rear mounted Fram HP-1 before the Holley Blue pump, then is Power Flow 6 an filter up front before the 750 HP. I really need more carb.
 
If you have a filter pre-pump you MUST use one rated for suction/ low pressure/ low back pressure. A mechanical pump has enough trouble maintaining a good flow without vapor lock/ boiling issues, a pre-filter acting as a restriction will only make that worse.
 
Some vehicles came from the factory with the filter on the inlet side of the pump, so I see no issue. My 75 F250 still has the original fuel filter bracket on the driver's side frame rail, about 12" away from the fuel pump, in the inlet line from the tank. There's a shiny new metal WIX filter clamped in it.
 
RustyRatRod said:
Some vehicles came from the factory with the filter on the inlet side of the pump, so I see no issue. My 75 F250 still has the original fuel filter bracket on the driver's side frame rail, about 12" away from the fuel pump, in the inlet line from the tank. There's a shiny new metal WIX filter clamped in it.
Click to expand...

I agreed ya on this, as I have seen a ton of them before the pump without issue except if they are sucking air from loose clamps.
Mine is back at the tank and before the electric pump which is also at the tank.
Also Wix metal.
Granted it's an electric, but still.
 
IIRR my new ootb 71 Duster 340 had two filters. You had to look hard or be under the car to see the one before the pump. The other was before the TQ carb..
IMHO There is a lot of good information here. The video is excellent and I don't really care for Holley, as a Corp.. I think their philosophy was to with hold info., so where their is confusion there is money to be made. Maybe they have changed, for the way I look at it.
I agree with AJ.
And as far as pumps, I'm going electric like Trailbeast.

I don't know about a streetmaster, I'm not a carb guy, but what about the cleanliness of the strainers, or whatever you call them, that are located in the carb. on the other side of the fuel line connection?
I guess you hope that crud never really gets that far.
Love this Site.
 
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