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  #1  
Old 07-18-2008, 06:07 PM
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T return fuel line, anyharm?

I found one post but didn't find enough info.

I've T'd my return line right before my primer pump, and back to the tank as to not filter the oil twice, could this do any damage or could i possibly suck fuel from the return line?

I did this to lower the vacuum on the veg fuel filter. I don't notice any difference in driving. I've checked my fuel strainer, lines, and think I know the system, but can only figure that the dent in my gass tank outlet is what causes the restriction. To add: On straight diesel the vacuum is the same as with veg oil and with a new 90t filter. (the vormax heat exchanger has a vacuum gauge)

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  #2  
Old 07-18-2008, 06:46 PM
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'Could you possibly be looking for the Performance Diesel Section?
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  #3  
Old 07-18-2008, 06:58 PM
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no problem

I have my tee right before the lift pump, after the filter, to save from the filter being in the fuel loop. the return to the tank is just to purge air.
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  #4  
Old 07-18-2008, 07:14 PM
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Why does it matter how many times the fuel goes through the filter? There's only so much dirt to remove from a gallon of diesel fuel.
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  #5  
Old 07-18-2008, 07:59 PM
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The more the fuel goes through the filter the cleaner it will be.

If there is a strong vacuum your oil is too thick or your filter too small.
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  #6  
Old 07-18-2008, 08:05 PM
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It couldn't be from this nasty dent?

The main thing I've noticed that the vacuum on the vormax gauge is the same even when running diesel.

But I guess if their isn't any harm with a T than I'll leave it.
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1980 300td (non turbo)225,000
1982 yamaha xs650,
I've also once loved
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a bunch of guitars and a banjo www.virb.com/sethlael

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  #7  
Old 07-18-2008, 08:12 PM
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Quote:
Originally Posted by Matt L View Post
Why does it matter how many times the fuel goes through the filter? There's only so much dirt to remove from a gallon of diesel fuel.
because heated veggi is always binding to itself and getting bigger. no matter how well you filter it, there is always more to filter.

and especially with a nominal filter like we use in cars. example: a 5 micron nominal filter typically lets particle through as big as 30 or 40 microns but gets most of them out. an absolute filter is the only way to filter absolutley on the first pass, but they don't make those for these applications.
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Old 07-18-2008, 10:59 PM
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Quote:
Originally Posted by seth411 View Post
It couldn't be from this nasty dent?
Yes, that could crush the pickup passage.
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  #9  
Old 07-24-2008, 05:37 PM
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Whats the amount of Vacuum it takes to pull fuel from tank

I put a fuel source right by my first filter and red 3hg.

I then connected the normal set up and counted about 22 HG at idle. (All new filters, clean tank strainer, but dented tank pc in previous post).

Whats your Hg from your tank? If my vacuum from the bent tank is causing restriction should I try to bend it back or would I need to replace it? Could it be anything else?

Thanks
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1980 300td (non turbo)225,000
1982 yamaha xs650,
I've also once loved
79 Bmw 530i, 69 VW buss, 78 Honda Acc, 79 Jeep wagoneer, 76 Peugeot 504, 82 fiat spider 124,
a bunch of guitars and a banjo www.virb.com/sethlael

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  #10  
Old 07-24-2008, 05:42 PM
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I don't know about your car, but the W210 incorporates a venturi pump driven by the return fuel flow. This sucks fuel out of low parts of the tank towards the pickup. You don't want to inhibit return flow to the main tank on these cars.

If your diesel tank contains such a pump, set it up so that you have full return flow when running on diesel.
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  #11  
Old 07-24-2008, 05:47 PM
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All I see coming from the tank are two lines, no venturi pump.
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1980 300td (non turbo)225,000
1982 yamaha xs650,
I've also once loved
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a bunch of guitars and a banjo www.virb.com/sethlael

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  #12  
Old 07-24-2008, 06:06 PM
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I can't see it on my car either, because it is inside the tank.
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  #13  
Old 07-24-2008, 06:17 PM
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Quote:
Originally Posted by seth411 View Post
I put a fuel source right by my first filter and red 3hg.

I then connected the normal set up and counted about 22 HG at idle. (All new filters, clean tank strainer, but dented tank pc in previous post).

Whats your Hg from your tank? If my vacuum from the bent tank is causing restriction should I try to bend it back or would I need to replace it? Could it be anything else?

Thanks
If that dent is causing fuel restriction, I would look for a new/used one. There is a chamber in the bottom of the tank that leads up to the tank strainer that I don't think you'd be able to deal with effectively without cutting it open. Just my 2¢.

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