S IV Fuel tank removal

[jmthehermit]

Hi Allan, the brown stuff of the float is residue from the fuel and its additives evaporating. The tan colored stuff on the other end is about the same with metal corrosion. Go to an auto parts store and ask it they sell a container of carb cleaner that can handle soaking a carb. It should have about a gallon or so of carb cleaner with a lift out tray. I know they make them but I never had to buy one. On the side of the unit there is a plate with two little screws that shield the internals. Remove the plate and soak the unit until it's clean. Do not use a brush inside it!!!! Do not poke at anything inside either. There is a small arm that runs over a small coil that sends the reading to the guage. Let the carb cleaner work alone. It will come out as clean as mine did. If you have difficulty finding the bucket of carb cleaner, find a small engine repair shop - read lawn mower shop - they should also be able to help you. cheers, Jeff

 

[SIVAllan]

Due to the amount of corrosion, it is not possible to see the little screws, even with a loop.

Any harm in soaking the whole float unit to reduce the corrosion so as to reveal the screws?

Thanks.

Allan

 

[SIVAllan]

Containers of carb cleaner found at NAPA ($100 a gallon) and O'Reilly's ($20 a gallon). Will dissemble fuel level unit and soak.

Zinc phosphate not found, but located alternate product OSHPO at a hardware store. OSHPO contains phosphoric, dichromate, wetting agents and extenders.

According to the label, OSHPO causes rusted surfaces to chemically change to inert iron phosphate (black in color). Recommended for use under all base primer. OSHPO is a rust inhibiting coating, not a paint.

No mention of zinc, which I am told is not a product requirement.

Comments on these products are welcomed.

Allan

 

[SIVAllan]

Containers of carb cleaner found at NAPA ($100 a gallon) and O'Reilly's ($20 a gallon). Will dissemble fuel level unit and soak.

Zinc phosphate not found, but located alternate product OSHPO at a hardware store. OSHPO contains phosphoric, dichromate, wetting agents and extenders.

According to the label, OSHPO causes rusted surfaces to chemically change to inert iron phosphate (black in color). Recommended for use under all base primer. OSHPO is a rust inhibiting coating, not a paint.

No mention of zinc, which I am told is not a product requirement.

Comments on these products are welcomed.

Allan

 

[jmthehermit]

Hi Allan, only soak the unit in carb cleaner. Nothing else! I took the cover off mine for a thorough cleaning because it was easy to do. If your unit worked before don't worry about taking the cover off, just soak it in the cleaner. Jeff

 

[SIVAllan]

Jeff,

Thanks!

After soaking, won't the unit need to be opened to air out?

What about the float? It looks like an old leather book binding with a coat of varnish on the surface.

The small float on the middle of the wire is corroded, too.

Allan

 

[jmthehermit]

Hi Allan, the carb cleaner will remove all the varnish and corrosion on the entire unit. All you have to do is occasionally agitate the cleaner to wash away the deposits while soaking. When clean, remove and let it air dry. I've included a pic showing the internals. There is only one moving part inside, so don't be concerned with whats under the cover. The cleaner will get to everything. cheers, Jeff

 

[SIVAllan]

Hi Allan, the carb cleaner will remove all the varnish and corrosion on the entire unit.

Hi Jeff, thanks!

When you say "entire unit" that excludes the big (and small) floats, right?

I'm concerned about them too.

Possibly a good cleaning would remove so much that the big float wouldn't float any more!

No way to know what's under the float's corrosion...

Allan

 

[jmthehermit]

Allan, submerge the entire unit, as in everything covered with carb cleaner, nothing exposed to air. Let the cleaner do it's work. It disolves varnish and the chalky like corrosion but does not eat metal. Over time the large float will appear just like mine, nice and shiny. To test the integrety of the float after cleaning, dunk it in some water and look for bubbles that might start to form where ever there is a hole. You probably won't find any.
The purpose of cleaning the entire unit is to ensure the float arm can move freely and you get metal to metal contact inside the chamber under the small cover. I pulled a unit which had this problem and it was corrected by a good soak. If your unit is OK after soaking and testing the float spray it with WD-40 or kerosene if your not going to install it immediately. The sending unit was made to operate in wet conditions and getting exposed to dry air for long periods allows the chalky corrosion to occur. cheers, Jeff

 

[SIVAllan]

Hi Jeff,

Thought I'd do a followup on the soaking process. The unit is coming clean, but slowly. If my vat of carb cleaner had agitation it would work much better. It's working as is though, if slowly.

Allan

 

[Green67Alpine]

Allen, Small air pump from a fish tank, solvent proof tubing, and a glass bead air stone all equal agitation, you can also just put a nut on the tube to hold it down. Adjust the air flow so you get a gentle stream of bubbles(you don't want it wildly bubbling) just to create some circulation of the solvent.

Tom j

Working on fine tuning the Strombergs.......then..........it's hit the roads !!

 

[jmthehermit]

Allan, it's looking good! The agitation will help alot in cleaning. You can also gently run a brass bristle cleaning brush on the really crusty parts too. I can't imagine what the inside of your tanks looked like if your sending unit was that gummed up. It's amazing that the majority of people don't realized what evaporating stagnant fuel can do to parts. Or even the fact that fuel can go bad.
I've been draining and changing fluids in the Alpine that I just picked up, getting it ready for storage. I'll be removing the fuel tanks tomorrow. Luckily the car is still outside because the fuel in the tanks is at least ten years old and does it ever stink!!!!! cheers, Jeff

 

[SIVAllan]

I received a mass mailing 5$ off coupon fromsupermarket, and picked up an air pump for nearly nothing, and some hose. Will rig up some agitation. A piece of metal fuel line should be fine for the hose-into-the-vat segment.

I started using the clothes dryer while running as an "agitation platform" and that is helping, but the air pump technique should be very helpful.

Hopefully I can start putting things back together SOON and get in some DRIVING time <s>.

Allan

 

[SIVAllan]

Another followup.

Have brushed the float a few times with a brass brillo pad, and lightly with a wire brush. Otherwise the assembly continues to soas in the 'bubble tank.'

Allan

 

[SIVAllan]

Note on use of Muriatic acid to clean crossover tube

I had hoped to file a final summary of reassambly this weekend, but hit a snag with busted bolts in the center crossover tube and decided to use the center crossover tube from my S V parts car.

After the earlier discussion on use of muriatic acid to clean the tube, and/or some product to then coat the inside of the tube to prevent the rust that can appear quickly after use of muriatic acid, I took the tube, two caps for either end from a hardware store, and a 2 quarts of acid to the radiator shop.

The shop guys let me cap the tube and fill it with acid in the back room. I shook it for 30 minutes by my watch, then poured out the acid and a shop guy applied pressurized steam to remove any trace of chemicals.

We looked at the results, and they were not entirely satisfactory.

The tube was not "silver" colored inside, but still mostly dark coated, plus some tannish power had built up here and there.

Returned to the back room, and repeated the process with much the same result.

I had hoped to clean the tube and dry it, then hand it immediately to the shop guys who would then apply the red liner.

The shop guys and I felt the acid was not getting the job done and we decided to let them boil it a few days in their acid vat, then red coat it.

This technique runs the risk of a patch or two of a light film of rust to appear between the time the tube is pulled from the vat and the time the red liner is applied.

I suspect that the red liner will provide protection as long as it lasts, well into someone else's lifetime, but once it fails, IF there is a rust film beneath the failed area, the fuel system at that time will be compromised to that (small/large???) extent.

I'm happy to be nearing the end of this procedure, but am a bit irritated that the pipe's inside won't be perfect once and for all time.

Allan

 

[Bill Blue]

Allan, the muriatic acid does not remove the old liner, which is the black stuff you saw in the tube. In order to remove that, you need to use a stripper. I had pretty good luck using some of the "heavy duty" paint stripper available at the big box hardware stores. The drill to do this at home is:

1. Plug one end of pipe, pour stripper into said pipe. Let stand a couple hours, check on progress, probably refill, wait some more, inspect, etc.
2. After all the liner is removed, use acid, either muriatic or phosphoric, to remove the rust.
3. Rinse.
4. Coat.

I know you are not going to coat your tube, but someone else might.

BTW, the dog and pony show of you using the acid is probably to avoid them from being classified as a metal finisher, thus coming under more regulations. As an ex sewer cop (state), I wouldn't buy it for a second. Its true that you as a non business can do it, and not be regulated. But they are skating on thin ice when help you do it so they can further process the part, which is their regular business. Tell them that a retired pretreatment coordinator says that being a good guy can get them into trouble.

Bill

 

[SIVAllan]

Bill,

Thanks for the information. I will say however that whatever muriatic acid removes, was removed.

It certainly removed all remaining paint on the Outside of the tube, leaving it near perfect for repainting.

The shop guys will remove the liner, there is no doubt. The potential for rust after that removal, and before they apply the red liner remains.

The crossover tube being used had no visible rust inside. So, at the beginning of the shop's vatting, no problem. Only a potential problem AFTER the vatting and BEFORE the red liner is applied.

I've been experimenting with acid and cleaning original hose clamps, and will file results seperatly.

Bottom line is that it is difficult to predict the degree of rust that will appear after an acid bath.

I suspect that to be true as well with a shop's acid vat.

Any metal that is sensitive to atmospheric conditions, once stripped of its "natural" protective outer layer, is vulnerable to corrosion. A fine, dry Arizona day with no humidity - little risk. A fine Georgia day with 99% humidity and no chance of rain - higher risk.

Fortunately, it is hot as h*ll down here and we are dry as a bone again, being temporarily spared from the tropical monsoons.

At any rate, the shop will apply the red liner after they complete vatting and I will reassemble the fuel system thereafter.

I'm sure the shop guys broke no laws, local, state or federal, or international. Shop guys...? Did I say shop guys? I was never
there...

Allan

 

[Jeff Scoville]

Any corrosion that starts between cleaning and coating are irrelevant.
The red coating can almost be applied without dipping and still last past when the tank rots from the outside in.
You will be fine.

 

[SIVAllan]

Jeff,

Thanks for that. I look forward to moving this forward, then on to the next system to trace/repair.

Allan

 

[dannym]

Citric acid is a much more preferred acid for rust removal. It is the primary active ingredient in commercial rust removal processes. It exhibits a strong preference for iron oxide, is a bit less hazardous than muriatic, and will leave a gray sandblasted appearance. The treated surfaces will acquire a light rust film on the way from the water hose to the coating bench! Be careful with all acids. They pose health risks.