Need to clean fuel tank - AGAIN

dllubin said:
The lower part of my tank has a bit of undercoating on it but it looks like it was from when I had the car undercoated when it was new. In this climate, it was probably more useful as sound deadening.
Click to expand...
Only the '85 has the extra factory coating (light grey color) on the lower half of the tank, and the standard factory coating (black color) on the rest of the undercarriage. My '79 does not, but it had aftermarket undercoating added to the whole undercarriage at some point. What a mess; overly thick and like you say, the bottom of that tank has some overspray on it, as does the suspension bushings, various rubber boots, one side of the axles/CV joints, part of the oil pan and trans, and many other undesirable areas. It was a SoCal car so the coating wasn't needed. In fact there are a couple of spots where water got under it and rusted the metal undetected, so I contend the car would have been better off without it.
I have removed undercoating on other vehicles as part of total restorations. It's a lot of work and makes a huge mess. I'd leave it and paint around or over it.
 
Dr.Jeff said:
Only the '85 has the extra factory coating (light grey color) on the lower half of the tank, and the standard factory coating (black color) on the rest of the undercarriage. My '79 does not, but it had aftermarket undercoating added to the whole undercarriage at some point. What a mess; overly thick and like you say, the bottom of that tank has some overspray on it, as does the suspension bushings, various rubber boots, one side of the axles/CV joints, part of the oil pan and trans, and many other undesirable areas. It was a SoCal car so the coating wasn't needed. In fact there are a couple of spots where water got under it and rusted the metal undetected, so I contend the car would have been better off without it.
I have removed undercoating on other vehicles as part of total restorations. It's a lot of work and makes a huge mess. I'd leave it and paint around or over it.
Click to expand...
Turned out the undercoating came off pretty easy with the wire wheel and there was not much of it - only the very bottom, so I took it off. I was rather amazed at the amount of runs in the factory paint. Not sure what sort of process they used but you would have to try hard to get that many runs. I almost considered stripping the whole exterior to bare metal, but then figured nobody was going to see it anyway and it wasn't going to improve the protection. Maybe that is what Fiat figured with their sloppy paint job.
 
That's very fortunate, otherwise it can be a real mess to remove.

It may sound a little weird but one way to replace undercoating with something much neater, lighter weight, cleaner looking, and more durable is to use a DIY truck bed liner spray instead of the regular undercoating. It still offers noise reduction and chip/rust protection but it's a thin and even coat instead of all that goo.
 
Dr.Jeff said:
That's very fortunate, otherwise it can be a real mess to remove.

It may sound a little weird but one way to replace undercoating with something much neater, lighter weight, cleaner looking, and more durable is to use a DIY truck bed liner spray instead of the regular undercoating. It still offers noise reduction and chip/rust protection but it's a thin and even coat instead of all that goo.
Click to expand...
That sounds like a much neater way to go. Speaking of cleaning things up, I'm trying to decide how to treat the insulation panel on the front of the tank. It had four clips holding it to the top seam of the tank, and the back (fuzzy) side of the insulation was stuck to the tank pretty well. This was the area where the tank was bare metal. No signs of black paint or adhesive to be found at that interface but it was stuck enough that a small amount of insulation was left on the tank when I pulled it off. I was thinking that I might just hang it off the top of the tank with the clips. I think the tank jams it in there pretty good so if the clips can hold it until it is in position, I should be set. If not, I've got a can of spray adhesive somewhere. When I pulled the tank, a small odd shaped piece of insulation backed by Masonite fell out. I haven't been back under there to figure out where it came from but I'm guessing by the shape it may be from the passenger side of the tank.
 
I don't recall for sure. But one of mine did not have much insulation on or around the tank at all - just some small pieces of padding to stop contact vibration with surrounding panels. The other tank had some sort of insulation stuck to part of it, which fell apart as I was removing the tank. I'd say it really does not matter too much how you do it. Pretty much anything will likely be better than whatever was there.
 
Matt at Bayless referred us to some 1/4" thick insulation with foil on one side on Summit's website, but we ended up going with a very similar product from Jegs, with foil on both sides. The choice was to make it as "fireproof" as possible. We then cut it to fit up one side, over the top, and down the other side of the tank and then used spray adhesive to hold it on the tank while sliding it into place. The car was in the shop for some body repair and we had them install the tank while it was on the lift. (we installed the tank in the 81 by tipping the car at nearly 45 degrees, while on our lift and decided that we didn't want to do that again.)
 
Rotated mine over a week, with 1 gallon of the Phosphoric acid from Home Depot. Left it on each side, ends and flats for a day each. Flushed it out with gasoline:

IMG_6389.jpg


My spare tank (1983?) from the parts car from Tyler (aarpcard) has the grey insulation added on the lower half.

IMG_6390.jpg
 
That grey coating on the bottom half is identical to my '85. The '77 does not have it.

I'm traveling so can only see thumbnail size images. How did the tank come out after cleaning?
 
Dr.Jeff said:
I don't recall for sure. But one of mine did not have much insulation on or around the tank at all - just some small pieces of padding to stop contact vibration with surrounding panels. The other tank had some sort of insulation stuck to part of it, which fell apart as I was removing the tank. I'd say it really does not matter too much how you do it. Pretty much anything will likely be better than whatever was there.
Click to expand...
After trying to install the tank without glueing on the insulation with little success, I decided to glue it on using plain old Elmer's glue. I figured that since it is water soluble, it should be easy to get the insulation off if I ever need to, and it won't attack the fresh paint:

X19 Gas tank after painting with insulation attached.jpg


I replaced the 4 small metal clips holding the insulation to the top tank seam with some split vacuum hose. This allows all the relatively fragile material to be grabbed. Also shown is my new filler hose. The old one had a tear almost all the way around the circumference between the two metal pipes. Good thing I haven't taken it to a gas station in 23 years or the gas would have gone right into that compartment under the driver's side engine compartment vent and out the drain hose under the car. I got the tank in and everything reconnected about an hour ago. That mysterious piece of Masonite with insulation attached turned out to be a panel that fills the void in the inner body sheet metal to the left of the tank. I'm sure the insulation is there just to keep it from moving once the tank is in place.

For laughs, here is a photo of the pre and post pump filters when the problem first manifested itself:

X19 Clogged Pre-pump & Post Pump Fuel Filters.jpg


The filter on the right is the WIX 33001 12 micron post filter which caught most of the particulates. The Fram pre-filter on the left didn't catch much. Both were replaced with WIX 33001 filters.
 
lookforjoe said:
Rotated mine over a week, with 1 gallon of the Phosphoric acid from Home Depot. Left it on each side, ends and flats for a day each. Flushed it out with gasoline:
My spare tank (1983?) from the parts car from Tyler (aarpcard) has the grey insulation added on the lower half.
Click to expand...
I was planning on using phosphoric acid, but after using the Oxi Clean, what I thought was rust turned out to be varnish so it was not needed.
 
One of my tanks had some edge trim across the top seam. I assume it was to hold on the insulation, before it disappeared. I picked up some more of that type trim to hold the new insulation on. I suppose it could work on the sides also. It looks like the door weather seal without the "bulb".
 
Dr.Jeff said:
That grey coating on the bottom half is identical to my '85. The '77 does not have it.

I'm traveling so can only see thumbnail size images. How did the tank come out after cleaning?
Click to expand...

Haven't even looked yet :D - It was pretty clean anyway, so I'm assuming the mung that came out is a mix of the phosphoric acid & whatever crap was predominatly sitting in the bottom / caged pickup area.
 
lookforjoe said:
I'm assuming the mung that came out is a mix of the phosphoric acid & whatever crap was predominatly sitting in the bottom / caged pickup area.
Click to expand...
Now that I'm back at my computer and can see the picture, it definitely does not look like any rust (a distinctly different appearance). This looks a bit more like the goo that "dllubin" and I had; I think a byproduct of some type of chemical reaction, along with some water/algae. The way it separates from the liquid is what makes me think that. Typically when I clean tanks it does not do this. I suspect Fiat coated the inside with something originally that has broken down and caused this slime.
 
Dr.Jeff said:
Now that I'm back at my computer and can see the picture, it definitely does not look like any rust (a distinctly different appearance). This looks a bit more like the goo that "dllubin" and I had; I think a byproduct of some type of chemical reaction, along with some water/algae. The way it separates from the liquid is what makes me think that. Typically when I clean tanks it does not do this. I suspect Fiat coated the inside with something originally that has broken down and caused this slime.
Click to expand...
If Fiat coated the tank, it is probably still on mine since water tends to bead on it and it does not rust. I'm pretty sure they did not use SS. I think my goo can be attributed to gasoline that chemically broke down. I did not see evidence of water as when I originally emptied the tank, I dumped the contents into clear half gallon juice containers. Looking at what was inside to gain some insight as to the tank condition, I did not see any liquid separation. If there was water, it should have been at the bottom.

Not sure if I am done cleaning yet. I went to start the car today and all I got was a few sporadic firings. After spending a bunch of time, it turned out to be erratic ignition behavior. I had the cap off to access the fuel pump in order to clean it out. Well, evidently some of that goo dripped out of a hose or something and decided to land right on the distributor points. More cleanup tomorrow!
 
After cleaning the goo off, the points and checking every component of the ignition system, the car still would not run. I finally discovered that some of that crap dripped right on the center of the distributor rotor. Once I got that off, the car started but the timing was so far off it would not idle. I finally got it close enough that I was ready to time it and then the starter stopped working. Solenoid engages but no power to the motor, and low current draw (solenoid only). I'll try wrapping it with a hammer and see if that works. If not, I'll pull the starter and take it apart. I had it apart before I reinstalled the engine to check the brushes, etc. and clean it up. Not sure what may have gone wrong but probably some electrical contacts need to be checked.

I never figured a dirty gas tank would take out the ignition system and starter in addition to the entire fuel system but it did!
 
I wonder if you will find some of the goo also fell on the starter motor? o_O Or is it possible that during the tank flushing (when the tank was still in the car) you got water in the starter, causing some corrosion?

The "goo" is acting like that old thriller movie "the blob", taking over your engine and surrounding components. :eek:
 
Dr.Jeff said:
I wonder if you will find some of the goo also fell on the starter motor? o_O Or is it possible that during the tank flushing (when the tank was still in the car) you got water in the starter, causing some corrosion?

The "goo" is acting like that old thriller movie "the blob", taking over your engine and surrounding components. :eek:
Click to expand...
It is sure beginning to feel that way. I got the starter out a few hours ago. Because I have those cooling hose protectors that came on 74s, I had to drain the cooling system enough to remove the top hose connections in order to get the starter out. Glad I only had water in the system - planning to do a chemical flush or two before putting in the antifreeze. The first thing I notice on the starter is that the lower solenoid terminal that connects to the braided motor + supply line is covered with that crap. I took the end cover off and was quite surprised at what I found. Around last New Year's, I had taken the end cover off to check the brushes and commutator. They were fine. I did some cleanup of the caked on combination of dirt and oil that you typically find in there. I cleaned the brushes and commutator with alcohol for good measure and put the thing back together. It was working great until now. Now, I open it and there is a film of some dark crud on the commutator that does not easily come off with alcohol. Hard to say how "the blob" could have made it that far, but perhaps the liquid that was carrying it had enough in solution and made its way in. I've got the starter fully apart and will begin the cleanup tomorrow. I may give the Oxi Clean a try since it worked well with the tank. I'm also going to use it to try and get that stuff off what was a relatively pristine engine compartment. I tried foam degreaser and that stuff is quite resistant to it. Carb cleaner barely works once that stuff dries and hardens.

I'm pretty sure the starter will work fine once I get it cleaned up. I was surprised how inexpensive some of the remanufactured ones are going for - under $60 including shipping. Not sure about the quality. Seems like most of our reputable suppliers sell them for 3-4x that amount so I'm guessing there may be much more to it than a large markup.
 
The problem with the old style starters is the high current draw & susceptibility to heat soak. The gear reduction starters are the best way forward.
 
My friend I hate to say it (and I'm not being sarcastic), but perhaps now you are beginning to realize why I was so adamant in the beginning that the tank should be removed to do any cleaning? I speak from experience.

Does the dark crud in the starter really look like the same matter that was in the fuel tank? That seems rather unlikely but anything is possible. As for the prices of remanufactured starters, absolutely no offense to any suppliers/retailers/vendors/etc, but price does not necessarily reflect quality. Regardless, if it needs to be rebuilt I'd be inclined to take it to a local reputable rebuilder and have your old one redone. There is more to it than replacing the bearings and brushes. Otherwise I agree with Huss about the gear reduction starters being a good alternative. However just like anything, there can be quality issues there too.
 
You must log in or register to reply here.
Back
Top