Fuel Bleeder Pump Installed

[chuntag95]

Since the other 2 threads have gotten too long, I am starting a third. YEA! :D
I got the bleeder pump installed and working. Pictures are at http://community.webshots.com/user/chuntag95
I have not plumbed it in to the return line because I had a temporary crown fall off and had to get it stuck back on. If you don't plumb it to the return, you need a cutoff valve. I put a momentary pushbutton switch on the power line so I can look at the sight glass, push the button and the pump runs as I watch for fuel.
I also made an 16 oz air trap. It's a Stanadyne bottle with a fitting JB welded into the bottom of it. I put a tee in the line from the EDU to the OEM filter. This should let me quantify how much air I am getting into the filters. Now, this is only temporary. Turn the torch off! If it were going to be there long term, a different solution would have been devised.
I also have the good sight glass still on the Mega bleeder port and it goes to the pump now. I was going to put another much smaller trap, made from a clear fuel filter, after the Mega to see if air was getting past. Only one tiny problem, I only had 1 1/2" tee and barb fittings. Oops. redface.gif I will pick up another one tonight or sometime.
Well, let me know what you think, I have on my flame retardant underwear. :D tongue.gif

[chuntag95]

Don't use a Stanadyne bottle for an air trap. The one I used got sucked flat in 25 miles. Check my pictures, I posted 3 of it is suck down mode. Tomorrow I put on the fuel filter instead. Live, experiment, learn mistakes, repeat as needed. :D

[chuntag95]

Judging by the bottle, it appears that there is a lot higher vacuum in the system than I thought. I need to get a gauge that has a max tattle tale or something. I might hook my boost sensor up. The 4" Hg is nothing compared to what is happening under load. :eek:

[pinehill]

Chris,

Which check valve did you use for the "power purger", and where did you get it? Have you tested the check valve yet by dipping the output hose into a bottle of fuel to see if it passes fuel in the reverse direction when the engine is running and vacuum is applied (Tommy's suggestion)?

[jbplock]

Well, I also installed the autozone E8012s “bleeder” pump . I took pictures and will describe the details, but long story short, - it bleeds the filter real good – maybe too good, as it also un-primed the clean side of the megafilter. After, I finished hooking up the pump, I had to crank the engine a few times to get it started. It acted just like it did when first starting after the initial install of the megafilter. It may have been because I was having so much fun running the pump, I pumped much more than was needed to just purge the air from the megafilter.

Here are the details (for pictures click on MegaFilter in my sig). I started by running a vacuum test of the sight glass, pump contraption. I temporarily assembled the whole bleeder system by hooking up the sight glass (clear filter) to the pump and check valve (the 1/8 NPTF threads on the filter-sight glass had to opened up with a tap). I then hooked up a MityVac to the input of the sight glass at the point which would be connected to the MegaFilter bleeder and pumped it down to 25 inhg. It held the vacuum solid – check valve works. Next I plumbed the contraption into the bleeder port and temporarily wired a switch and power to the pump. I Ran the pump about 30sec and fuel filled the sight glass and ran out the hose on the end of the pump through the check valve (on the pump output). One interesting observation at this point was that once the bulk of the air was purged from the megafilter, the fuel ran clear with no bubbles in the sight glass. The design of this (filter) sight glass is such that fuel enters one side and travels half way up a hollow tube that is perforated and plugged in the middle. Fuel coming in to the vertically mounted sight glass, exits the holes in the tube on the bottom (inlet) side then re-enters the holes in the tube on the top (outlet) side. This center tube is normally covered with a screen, which I removed. It was interesting to note that with the pump running and drawing fuel from the top of the sight glass, it would only fill to the level of the highest hole in the center tube…. Maybe this is what is happening in the megafilter, the fuel level equalizes at the level of the suction side nipple leaving an air space above the filter. In a “tight” system this is not a problem as it acts just like a filter with out the long nipple, but if there is a leak, the air space can grow and un-prime the system (??).

Well anyway, I found a nice place to install the pump (see pictures) behind the grille using an existing bolt. I didn’t finish the switch installation but I plan to mount a fused push button starter switch ($3 Wal-Mart special) some where under the hood when I get more time (it’s Mothers day). I also saw a tank filter at Tractor Supply that may work nice for a bleeder tank mounted low behind the grille where it could be accessed. It has a large removable plastic bowl with a cartridge inside and a petcock on the bottom. The cartridge could be discarded and inlet could be plumbed to the bleeder pump outlet. A check valve could be put on the outlet (to release air when bleeding) and the petcock could be used drain when full.

For now I’m just going to DRIVE and NOT bleed and see what happens. (I also have a feed-thru petcock on the end of the bleeder hose to defeat the check valve incase I want to pump up the primer). I’m still not sure if the bleeder pump will work for quick air purges since it de-primed the inlet to the OE pump the first time I tried it (at least I have a cool way to prime the system when changing filters). I also thought of running the bleeder pump to purge air when the engine is running. This way the OE pump will keep the clean side primed while the bleeder pump purges air, but I’m not sure if it would be bad for the OE pump to fight for fuel.

All comments, flames, and suggestions are welcome! :D

Pinehill,

Chris and I got our check valves from MSCdirect.com (PN 04108676 1/8NPT, $7.50). They have other sizes too.

[ 05-11-2003: Message edited by: jbplock ]</p>

[chuntag95]

jbplock,
How did you find out your pumped out the clean side of the mega? I had no start problems, even when I pumped a gallon of fuel through the pump playing.
Even though it's Mother's Day, I need to take that bottle off today. It's not doing much for me anyway.
Later,
Chris

[pinehill]

I was wondering earlier if that wouldn't happen (drawing fuel back through the Mega clean side outlet when the power air purge was running), but then I thought, naaah. My solution to that imagined problem was to install a normally open solenoid valve on the clean side outlet, wired in parallel to the purge pump. Are we getting a bit complicated here or what?

[dmaxalliTech]

I am amazed at the ingenuity of you all. I dont think Bosch put that much thought into the design of the whole system!! I am SOOO glad I dont have these problems, yet. I am putting on 2 more MEGA kits in the coming days. It will be interesting to see if they have trouble also....

[Kennedy]

Since the supply and return are in fuel then the air had to come from a leak (supply OR return side) or a massive "outgassing" from the fuel present.

[jbplock]

Chris,

I’m glad to hear you didn’t have any starting problems after running the bleeder pump. I’m not exactly sure what happened with mine. Since I had pumped the air out of the system with the bleeder and them experienced a 3 to 4 crank hard start, I guessed that running the pump pulled fuel form the clean side too.
At this point I’m just going to run without bleeding until I get a no start or accumulate about a 1000 miles. At this point I’ll try the bleeder and see if the hard start happens again. The only other thing is that I had the system open for several hours while I was tinkering. Could this have allowed the clean side to drain back into the MegaFilter (with bleeder open)?

John,
Regarding,
“Since the supply and return are in fuel then the air had to come from a leak (supply OR return side) or a massive "outgassing" from the fuel present.”

Do you think a leak would explain why the clean side un-primed? After the air was purged, and the pump was running I didn’t see any bubbles in the sight glass. :confused:

[chuntag95]

I changed out the bottle and put on the clear fuel filter, minus the filter. I did make use of my bottle and put it on the hose to catch any fuel from the air purge pump.

I like the solenoid idea. You could even plumb it where you could pull from the clean as well. If you wanted to pull/push through the system.

I am thinking maybe I did this backwards. Maybe I should have put the pump before everything. Plumb it so that you can switch a valve or two and push the fuel, but not have it in the path all of the time. Maybe a duel solenoid setup? Put a sight glass/bleeder right before the engine, post everything. With the bleeder on the OEM, the Mega and just before the engine, you should be able to get ALL the air out. With my pre filter air trap, I have no way to easily purge the air out. I also need to break out my Dremel and start cutting off collars on the fuel hoses. I am going to plump the return from the pump to send it to the tank if I don't move the pump.

Thoughts on the lastest brain shower?

[chuntag95]

Does anyone know of a place to get an affordable solenoid?

My catch bottle is vacuum tight, so I have to remember to open it to purge out the air.

I am looking a relocating the pump to push instead of pull through the filters. It will allow me to purge the air out of my trap as well, so I can quantify the amount of air coming from the line/tank.

[chuntag95]

Well, I decided to move my air trap to post Mega this morning. I can now purge the air out of it without pressurizing the tank. Also, I can see if air is getting past the Mega at some point. I get air every time in my Mega, but have not had a stall. I went 330 between bleeds this last tank. With the trap moved, I am just going to check it and see when it starts catch air. I'll keep you guys informed.

On a different note, I heard about someone(s) putting some hose on the top of their Mega to make a big air trap. How is that going and does it work well for telling you how fast you are collecting air?

Modify On! :D

[NWDmax]

Chris:I put a clear hose as an extension of the Mega filter head bleeder port.
I used a 3/16" nipple with 1/8" npt coming out of the filter head and adapted back to female 1/8" npt to fasten the original bleeder valve to.
It works very well but I'm still seeing a lot of air.
I just finished with the Mityvac test of the stock filter and head as well as the Mega filter/head combo.Both held over 15 hg for well over two hours each.
Its all back together now and I ran it in the driveway for a few minutes.After shutting down the bubbles continue to rise in the bleeder line for quite a few minutes.(it was still doing this when I came in)I'll check it in the morning and I bet the hose is almost full of air.
I figure the big filter just takes awhile to purge all the air out of it.
Next step is to replace the QD's with hose and see if that slows my air collection.
I'll let you know tommorrow after I get to work if anything has changed.
Sounds like your project is going well.
Blake

[jbplock]

I had my first start and stall at approx. 350 miles since the previous bleed. Ran my pump/bleeder contraption and it started right up. So, for now I'll be bleeding with the pump at every fill-up or about 200-250 miles. Currently I’m bleeding into a plastic bottle from a short hose connected to the pump that’s coiled up under the hood. To make it practical it would have to be plumbed into the return line or a reservoir that could be periodically drained. At this point I’m not sure if a suction bleeder is the best way to go.

[chuntag95]

NWDmax,
I put on a clear hose coming out of the bleed port last night. It is 1/2 ID hose, about 3-4 foot that I had left over from playing around. I purged out all of the air except one tiny bubble that just would not leave. When I got to work this morning, about 17 miles and 35 minutes, I had 22 inches of air in my tube trap, but none in my post mega trap. After some math, assuming the diameter is round and constant for my tube (which it is not) I have 8.6 in3 of air or 140 cm3 worst case. Either way, that is a lot by my thinking.

NWDmax, can you give me the numbers on your tube so we can compair time or miles vs. air quantity? If we have minimal air coming into the system and most of it is coming out of solution, then it should be similar quantities. Temp and pressure will play a role in it as well.

I need to measure my Mega or look up the specs to see what volume it has. I should be able to calculate how long it will take to fill up assuming a rate of air collection.

I wonder if a positive pressure in the system would change the quantity? It would some, since the air will compress.

Does everyone else's fuel look like Mountain Dew? tongue.gif Talk about a kick. :eek:

[NWDmax]

Looks like mountain dew for sure!Thats exactly what my daughter said when she came out to the garage.

Chris:My bleeder tube is 3/16" id and 2' long.Its was totally full of air this morning and took 3 10 pump and bleeds before I saw fuel again.
Since I had drained the Mega filter and changed the stock one I won't be getting accurate results till today.I'll report back later.
Blake

[jbplock]

Blake,

I just noticed the following from your earlier post

[chuntag95]

2 cycle oil? Is that for the extra lube properties or did you confuse your DMAX for a weed eater. ;) tongue.gif I heard on one guy using transmission fluid when he put in unleaded. :eek: I wonder if he had organge?

[NWDmax]

JB:Using the hoses with clamps JK provided on the Mega kit and I smeared some of the dielectric grease on the hose as well.
My bleeder tube gets full of air in a 5 mile drive so I'm getting a lot of air from somewhere.
Tonight (wife willing) I'm going to remove the QD by the firewall and test/reintall with 3/8 fuel hose and clamps.
Chris said he reduced his incoming air considerably by doing this so we shall see...
Give you a report tommorrow. smile.gif