[littlered380sl]

Swril Pot please identify parts. have pictures

First question, is the circled part, the gas inlet into the swirl pot (not the return fuel)? If so I believe mine is plugged, I run out of gas basically 1/2 tank. The premise of the swirl pot was to reserve enough gas to feed engine when turning? It seems you can't get to this part to unclog it, short of cutting tank apart. Any ideas, can one just right angle large holes and bypass this situation, at least ill get use of more of the gas tank. FYI, I have had my tank out and it is spotless, and its not a fuel filter problem, remember 1/2 tank no gas. Ideas please.
*(this is not a picture of my swirl pot, just what i could find as an example)
Rick

 

[Weather Man]

Mine was like that when I first acquired it, could use only half a tank when it balked and bucked and just would not run. This was the result of sitting for almost six years with half a tank of gas in it.

Six months of a steady diet of Techron cleared it up.

 

[mach4]

There's almost no possiblity of what I'm about to describe being your problem, but because of the similarity in symptoms, I toss it out as something that can be checked visually in about a minute or less. If the PO had a problem and was aware of the following "trick" he might have tried it.

In the diesel world, when an engine quits running, or runs very poorly indicative of fuel starvation, a common diagnostic is to swap the supply and return lines to the tank. This uses the return line which is about half way up in the tank to supply fuel and therefore must have over half a tank to work. If the screen is clogged, the engine will start running properly and everything but the screen is therefore ruled out.

In a diesel, this is easy because the pump is on the engine and swapping lines is super easy. On a gasser it would take a bit of doing to replicate this as the lines would need to be swapped at the tank. A quick visual inspection would be obvious.

Since the screen is such a pain to change, it's possible someone made this "quick fix" and just lived with it.

 

[MBGraham]

There are other threads about the swirl pot. Haven't done a search, but one forum member did a good analysis of what is going on.

From what I recall, the circled part in the pic, is a venturi. The return fuel line is connected to it and it uses that fuels motive power to such fresh fuel off the bottom of the tank. If the venturi is blocked, only way fuel can get into the swirl pot is by overflowing which requires tank to be 1/2 full. If venturi is blocked where does return flow go? Can you blow through line?

Re your question - You do need the screen. If you could use the screen outlet nozzle to drill a small hole in the side of the swirl pot just to let fuel in, that might work. But I still wonder about the return flow. If line is blocked, you are dead heading pump and the fuel pressure regulator would not work on my djet. Not sure effect on a 380SL, but it can't be good.

This subject has been discussed at length in past ( I see you have been there) But there are also several other threads.

 

[ChipMoore]

RE: how to unblock a return line. My return line was 100% blocked. I had already removed the tank to clean and after a couple rounds of power washing through the fuel sender and fuel screen openings, spraying with phospheric acid, neutralizing with baking soda, and power washing again and drying with the blower end of a wet vac, it was finally clean. However, I did notice that water would not flow from the return line. I tried running a length off weedeater line (you need about 18" or so to reach the swirl pot) through the return tube, but that would not clear the blockage. After scratching my head a bit, I took a length of 1/16" wrapped wire cable, splayed one end a bit so it would tend to spread open when it hit the blockage, chucked the other end in my drill, ran it down the tube, drilled away, and VOILA, no blockage. Of course, I had to clean the tank again to remove the debris, but that was no biggie.

 

[rowdie]

RE: how to unblock a return line. My return line was 100% blocked. I had already removed the tank to clean and after a couple rounds of power washing through the fuel sender and fuel screen openings, spraying with phospheric acid, neutralizing with baking soda, and power washing again and drying with the blower end of a wet vac, it was finally clean. However, I did notice that water would not flow from the return line. I tried running a length off weedeater line (you need about 18" or so to reach the swirl pot) through the return tube, but that would not clear the blockage. After scratching my head a bit, I took a length of 1/16" wrapped wire cable, splayed one end a bit so it would tend to spread open when it hit the blockage, chucked the other end in my drill, ran it down the tube, drilled away, and VOILA, no blockage. Of course, I had to clean the tank again to remove the debris, but that was no biggie.

Thanks. I knew someone had cleared it but couldn't remember who or find the thread.

 

[MBGraham]

After scratching my head a bit, I took a length of 1/16" wrapped wire cable, splayed one end a bit so it would tend to spread open when it hit the blockage, chucked the other end in my drill, ran it down the tube, drilled away, and VOILA, no blockage. Of course, I had to clean the tank again to remove the debris, but that was no biggie.

Great - a Roto-Rooter solution!

I have used a similar idea to clear underground drains around our house. Used an old 30ft 1/4" s/s stay from a sailboat with one end splayed open and my 3/8" drill.

One problem for the OP could be that the return line might be clear, but the entry from the bottom of the tank blocked. I seem to recall one member clearing that from above with a bent welding rod, or something. Soaking with one of those rust eaters (Evaporust?) might also help.

 

[littlered380sl]

Identifying swirl pot hoses. Have pictures

Identifying parts please. Have photos. * You might want to look at all 3 photos before trying to identify.

Pic 1
These two lines A and B are on the driver's side in front of fuel tank. Line "A" seems to run across to the passengers side which is the 2nd picture (passenger side of fuel tank). So what is line "A"? Also, this dosn't look right for that line "A" ( Pic 3 is a close up pic), there is no hose on top of this check valve (circle "C" pic 1)? Is this even the correct check valve? If so what is spouse to be connected to this top part of the check valve?

What is line "B", is this the return line that goes into the swirl pot that creates the suction for the ventricle to move fuel that is below the swirl pot?

Clarification?
Pic 1 is identifying 2 hoses (A&B) and no hose on check valve ("C").
Pic 2 is just a pic of hose "A" from drivers side to passenger side of tank.
Pic 3 is just a close up of hose "A"'s check valve with no hose on top of check valve.

 

[Weather Man]

Those are components of the breather system I believe. And no, that check valve does not look correct. Pictured are the in-line valve (the one that ought to be shown in your pics but isn't) and the 3-way at the canister.

 

[littlered380sl]

Thats what i thought, i know i installed (your picture one on the left) inline check valve about 3 years ago on my car and know after two different mechanics later (different work done on car) my inline check valve was replaced by the 3 way valve. What the crap! Would this cause my gas starvation problems?

Now as far as the inline check valve, which end is the tank side, gray or white?
I'll have to try to find my order to get the part number and reorder it.
Thank you for your help.

 

[Weather Man]

In your final picture with the drawn circle you can see the line from the tank coming up from below. This line would connect to the black nipple. The line from there to the canister carries on from the white nipple.

Yes, if you have the valves swapped or reversed, you would develop a partial vacuum in the tank as fuel is withdrawn leading to fuel starvation. In the worst case, I have seen pics of imploded tanks where it just collapsed from external air pressure.

 

[littlered380sl]

Weather Man, are you saying the bottom line (picture 1, labeled “b” should be hocked up to line labeled “A”, my lines are crossed?

 

[Weather Man]

Looking more closely, I see one photo with no numbers or letters. The check valve is circled. The line from the tank is not connected, I can recognize the black nipple. Hook that up and you s/b okay. Test by blowing back through it at the canister. Another test is the filler cap, s/b an outward rush of air and fumes when opened. If you replaced that valve three years ago it ought to be fine.

But listen, this is all explained in the M116 engine manual, chapter 47-200. Do you have the CD? Perhaps it is in the EGv107?

 

[littlered380sl]

Thank you W.M.. darn, your right the hose was off. So it is the correct check valve after all, and here i went and bought another one $30.00 wasted. Now i'll drive car until I get to about 1/4 tank and see if the swirl pot ventricles are working correctly? I'll be driving with a 3 gallon temp plastic gas can in case ventricles do not work.

 

[littlered380sl]

This normal?
As I was running gas down in car, for about 1 1/2- 2 hrs, the vent line dripped a couple drops of fuel at the connection from the gas tank to the check valve (the connection was unplugged)? (picture 1 above). Is this normal for gas to travel into the vent line going to the canister? Car was just under 1/2 tank full.

 

[Weather Man]

I think you're making progress but did you not re-connect the line? There ought to be only fumes in that line especially in Arizona -- too warm for condensation.

Running it down -- I did the same thing for a week, after about six months of Techron treatment. Until then I could not go below a half-tank. I stayed close to home.

 

[littlered380sl]

I'm sorry, i now live in Florida. But yes cable is now connected and as stated dripped a few drips after running down gas (2hrs). As of today I'm at well below 1/2 tank, about 1/2 tank and 1/4 tank. Going on drive today (extra gas tank with me) and trying to run fuel level below 1/4 tank .*Oh, the line is clear from canister down to where the check valve connects (check valve of course not connected). I could easily blow air thru the line.

Thank you W.M for taking the time in helping me, Rick