I pulled my fuel tank today and it seems to have baffels. Normally this would be a good thing but apparently the rear baffel section (with the tank drain) isn't talking with the middle cause it's bone dry and the middle had about 3 gallons gas. The middle baffle section isn't talking with the front section because that's where the fuel is taken (that really isn't good because despite 3 gallons of fuel it isn't making it to the fuel line).

I suspect there is some sediment (maybe silt or??) sitting on the bottom that is covering the holes that connect all three sections. Is anyone familiar with this design and is there a suggested remedy? I have access to the rear two sections via caps on the top of the tank but the section that feeds fuel line has no access from the top.

The physical condition of the tank is good on the outside. Is there a technique short of a small thermo nuclear devise that can clear the mess on the bottom. I can steam out the two sections from above but can't get to the third section. I guess I could pour something like acetone in there but if the gasoline isn't clearing what's blocking this passage, then the acetone probably won't be very effective.

Any suggestions or words of wisdom from the old Cat clan.

Thanks,
Tom

Tom,
My 30 has a two compartment tank, a small one for gasoline to start the engine on and a large one for tractor fuel to run the engine on after it is warm.

Bob

Bob,

Thanks for the reply. My tank has three sections with two fill or vent holes on the top. It has a fuel shut off valve in the front section that supplies the Ensign carb. The rear section has a little brass water drain spicot and nothing in the middle section but the opening for the fill. The baffles have approximatly 1 1/4" holes in the top and I presume the same on the bottom.

I plan to take the tank to a car wash and spray around in it with some detergent and hot water spray. I'll also probe the bottom sections that I have access to determine composition and thickness of sediment. Hopefully this will give me a idea wht might be effective in removing this mess.

Thanks,
Tom

Hi Tom,
Ya might try getting in there with an air lance (1/4 in. tubing, 100 psi air) to stir things up a little as part of the cleaning process. Seems to work pretty good at stirring up bottom sludge.

Hi OM,

Thanks for the tip. I got a lot of air pressure and can rig some stiff tubing to get on bottom. Does this technique use fluid on the bottom or is it just air pressure into the sediment? I suspect this stuff is mostly silt that has accumulated over time with a little fuel varnish as a bonding agent.

I've gotten several good suggestions and I'm very interested in seeing what might get those three sections talking with one another. Cutting the ends off the fuel tank will be a last resort. The tank is original and very dent free. It would be a shame to butcher it up if there is a less intrusive way.

Thanks,
Tom

Works either way, just one can gets a little messier than the other. I've even thrown some old nuts and bolts in there to rattle around with the blasting (so long as you can retrieve them). Some of those chemical etch/cleaners work pretty good to but they have limits. Would be a shame to cut it open but it's a possibility.

Mystery solved! Bob, you were right on. Let me explain. I did a little more looking into the baffles. The second baffle was fairly accessable and I did a bit of probing with a long metal rod. The key to my "DUH" revelation was there is no vent at the top of the baffle. Obviously, communication was never intended with the other two sections of the tank, hence it was bone dry. Someone pulled the shutoff valve and installed a drain cock versus a simple plug. Very evil person to do something like that. This section was obviously intended for gasoline.

I still have the residue in the other two sections. This stuff appears to be a wax like dark brown substance that doesn't contain much silt or rust and should dissolve with a little heat. Probably fuel varnish is a semi paste state that hasn't had a chance to get hard because of the fuel in the tank. I'll spray a little flat black paint on the bottom of the tank and let the tank sit in the Texas sun for awhile, then try some of the suggested techniques for removal.

Thanks again for the help,

Tom

Hello, The thirty tank has two separate parts. the large compartment goes towards the front of the tractor, with the small compartment towards the back of the tractor. On the later tractors the small compartment had a petcock on it, thats how the parts book shows it originally. I think the small tank with the petcock was intended for storage of gas for priming the engine during startup. The large compartment has one baffle in it. This is the tank that is plumbed to the carb. All the seams are soldered, so be careful if you use any heat on the tank. The seams can be hard to re-solder because of contaminents in the old metal. I have a couple of Sixty, and Thirty tanks that I need to clean. I was told that acetone works good to disolve old gas varnish. Hope this helps. Caterpillarman

Thanks Cat Man. I've got a fairly early Thirty (PS 3454) and have the drain petcock. I initially assumed it was a tank water drain before discovering no connection with the other two sections.

My engine also has the two cups mounted just inside the intake manifold ports on the head for priming. The cups have cute little lever operated covers that expose the cups for fuel. I'm assuming the rear tank was used by despensing a little gasoline in a container and then the operator poured this in the primer cups.

I don't have a parts manual for this Cat but will get the first one I come across.

Would you know how large the holes are in the bottom of the baffle?

Thanks,
Tom

Hi Tomseabee,
drawing calls for 1 1/4" Dia hole top and bottom of the baffle.
Regards
Eddie B.