A hypothesis please!

[BADSAM]

I traded/purchased for a suburban about 6 weeks ago. It's story (they all have a story) was that it was a daily driver before the guy blew the bottom end of the engine. So I had an engine rebuilt for it, installed it and took it out for it's maiden voyage on Monday. I did a short trip (3 mi) around the neighborhood and it performed flawlessly. So I took it down to the gas station (4 more miles) and filled it up. On the way I felt a slight hesitation. After getting gas (I filled up) I decided to push it a little and headed out for a little longer drive, I went about 5 miles and turned around, on the way back the hesittaion came back and this time with a vengence. I had problems getting home, it was surging going up a hill, hesitating , etc. It felt like a clogged fuel filter. But I did make it home.

Sure enough after investigation the next day, I found crap in the fuel filter, flakes and what appears to be rust particles. I also tested the fuel pump and it's fantastic.

I cleaned the filter out and then took it for a shorter trip, even went down and up that big hill again. No problems. Although there was more crap in the filter by the time I got home.

So I figure the PO told me a tall tale about it being a daily driver and I pulled the tank today. To my surprise the sending unit is relatively new, the sock is in great shape. I could find no tears or rips in it, still very pliable. Looks NEW, as does the rest of the sending unit.

The tank is not corroded or rusty. It looks very good. There are a few flakes of ??? at the bottom of it. But it's not from the tank corroding.

So where is the crap in my fuel filter coming from?

My guess is:

1. Before sending unit was replaced there was no sock and debris collected in gas line, I had the good fortune during my cam break in to break all that crap loose in the line. Or rubber lines are deteriorating (but it looks like rust flakes?).

OR

2. Aliens put it there.

My plan is to go ahead and clean the tank out, blow all the lines clear with my air compressor, and replace all the rubber lines.

What's your hypothesis?

Thanks

[cdowns]

or your steel gas lines are rusting from the inside out

[Green Machine]

Originally Posted by cdowns

or your steel gas lines are rusting from the inside out

You could install one of those clear plastic filters between the tank and the fuel line to catch any crud till it gets flushed from the tank, won't help if lines are rusty, and not a good long term fix. Really should not have a filter on the suction side of the pump, could cause vapor lock when the temp is warm enough.

[texanidiot25]

Sounds like me last month! I've just kept a few fuel fitlers on hand and have not used the q-jet one (clogged in an amount of hours), and just used the G12 Fram one from wal mart. The moment I felt a sign of fuel problems, I pulled over into a parking lot, layed a rag under the filter, and swapped filters. Then drain the filter out and toss it in the bed. Once it dried if it flowed OK (blow with your mouth) I kept it handy as an emergency spare. Took 3 weeks of that til the dirt problem stopped.

But of course, my truck has sat for 2 years..

[special-K]

Can you see the bottom of tank is clean,for sure?I`ve seen original units look new and I`ve seen them look 40 years old.If someone ever used leak stop it could be breaking down.

[BADSAM]

The tank looked pretty good, it did have some discoloration and a few small flakes it. It also had a very light residue on the walls and roof. I went ahead and took it in today to be cleaned at the local radiator shop. Should have it back Wed.

Nothing in the tank looked like what I was seeing in my filter. Anyway, I'll blow the lines out and put new rubber hoses on. Then see how that works.

Anyway, we are all wearing our armidillo hats in case the aliens come back.

[oldgold70c10]

I poured what looked like 2 cups of coffee grounds from my tank when I had it out!

You might want to check your metal feul lines for soft spots if the stuff is coming from them and not the tank.

[mr48chev]

Did it have the gas cap on it when you bought it? I had a terrible time with my 51 Merc because it sat with the gas cap off for a long time.

I'll second putting an inline filter in front of the fuel pump or between the tank and pump. I'm another one who has had to change them on the side of the road but that is easier than being stuck with a plugged pump or carb.

[BADSAM]

Yep, it had a cap on the tank. I'll be blowing the lines out tomorrow, so I'll check em whille I'm at it and find out more then. I think carrying around a couple of spare filters might be a good pathforward here in the short term.

Until then ... I'll keep a watchful eye out!

[notsolo]

Originally Posted by BADSAM

Yep, it had a cap on the tank. I'll be blowing the lines out tomorrow, so I'll check em whille I'm at it and find out more then. I think carrying around a couple of spare filters might be a good pathforward here in the short term.

Until then ... I'll keep a watchful eye out!

The new fuel with ethanol is also a better solvent than good old gas, alcohol tends to clean and sometimes eats gaskets,good luck carry extra fuel filters!!!!!!