Fuel Delivery Issue

bluebird · March 25, 2016, 12:17 PM

WOW, that is bad. I know there are solutions out there for cleaning and coating the inside of gas tanks, but I've never used any of them. Don't think they are cheap either. I'd try googling gas tank cleaning and see what you come up with. You do have your work cut out for you.

joev · March 25, 2016, 12:34 PM

I have taken fuel tanks in to be sandblasted before then take fiberglass resin and coat the inside of the tank with it had good success with it one option

BrianB · March 25, 2016, 03:30 PM

I would clean the tank up instead of replacing it. The tank itself looks to be in good shape as best as I can see from your photos.

You could try putting a couple gallons of fresh gas in there and see if that starts dissolving the gunk. Or maybe try some Xylene (found at any home improvement store). Get the sludge loosening up and dissolved and dump out the tank into a 5-gallon bucket. Repeat as necessary.

There is a product called POR-15 that's used a lot for DIY motorcycle tank repair (https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#safe=active&q=por-15+fuel+tank) but it's expensive.

If after cleaning it looks like the metal is sound, I wouldn't bother with a sealant. Just paint the outside and keep good clean gas in it from now on. Should last the rest of the life of the vehicle.

solracem · March 25, 2016, 04:15 PM

Thanks for the heads up! Currently it's sitting with 2 gallons of acetone in it and I plan to slosh around a few gallons of cleaning vinegar in it too then power wash it. After that I'm hoping it's still in decent shape and then I plan to take it to get cleaned at a radiator shop I found here in Austin. They charge $125+ to get these things cleaned, so, kinda steep in comparison to just replacing it. However, I can't find a replacement. After that I was thinking I should take the time to seal it but, you're suggesting that I don't. Why is that?

M & J · March 25, 2016, 06:36 PM

I didn't realize POR15 was fuel proof. We used to something called KREEM in motorcycle fuel tanks to preserve them. The prep work to use it was several steps however.
Glad to see there is an in tank pump. Others have replaced that entire float/pump assembly and part numbers are in the other threads.

BrianB · March 25, 2016, 08:09 PM

Quote from: solracem on March 25, 2016, 04:15 PMAfter that I was thinking I should take the time to seal it but, you're suggesting that I don't. Why is that?

To be honest, I went back and looked at the pictures closer and there is a fair amount of surface rust inside. But if you have it professionally cleaned and it removes the rust, then keeping the tank with good fuel in it should (in my opinion) be good enough.

I can't tell with your tank, but mine has baffles in it that would make it impossible to seal it from the inside and believe that I got every inch covered.

Others here may have different options.

solracem · March 28, 2016, 09:37 AM

BrianB - So, I decided to soak it in a combination of acetone, vinegar, and degreaser for a couple of days. After I power washed some of it out, it looks much better! I dropped it off at a radiator services shop for a more detailed cleaning and should have it back in a week.

I'm also going to take Mambo's advice and have the sending unit rebuilt. Hopefully I'll have everything back together in the next couple of weeks.

Check out the pics! And, thanks for all the advice/help

tiinytina · March 28, 2016, 11:42 AM

I just helped Brad drop Gone's tank on Saturday.. the PO had at some point had an external fuel pump installed (yea). We dropped it low enough to replace all the rubber connector hoses (return hose had frayed at clamp) but didn't remove the sending unit.. never been accurate. bolts etc were in good shape and came off easily after PT blaster. we did have to end up using a piece of radiator hose to reconnect fill port to fill pipe as all we had available, deal with finding a better option when I can but was a perfect match size wise since of course port and tube have different OD's... glad I didn't pull the sending unit.. if it aint' broke don't fix it rule... fingers crossed.

joev · March 28, 2016, 12:32 PM

Wow good job on it if you did it one more time yourself you would be good to go I think

solracem · March 28, 2016, 02:20 PM

Quote from: joev on March 28, 2016, 12:32 PM
Wow good job on it if you did it one more time yourself you would be good to go I think

Thank you, very much appreciated! I figured I'd let a pro get their hands on it and do it right. However, they're charging me ($125 - $250) based on the amount of times they'd have to put it through chemicals so I'm hoping my efforts cut it down to once.

It also has some walls built inside that seem like a series of doors and passage ways to prevent fuel from draining to one side of the tank. I wasn't too sure what would be best to get around those and clean. Figured they'd do a better job than me and I'd break even on costs if I did it myself. The radiator services shop also has access to more powerful chemicals and a pretty powerful pressure washer that shoots boiling water into it.

I sent the sending unit off to Don over at Tri Starr to have it rebuilt. He seems to think he can rebuild it, so, I guess we'll see here in a couple weeks.

M & J · March 28, 2016, 02:37 PM

On one thread someone posted a replacement part number and cost for the pump/sender unit. You sure rebuilding is a cheaper option?
I found this thread showing a picture of the unit saying it came from Dorman but no part number was listed.

http://www.classicwinnebagos.com/forum/index.php/topic,8656.msg42404.html#msg42404

Without having specifics I found this unit: http://www.rockauto.com/catalog/moreinfo.php?pk=1027304&cc=1163359&jnid=529&jpid=1

solracem · March 28, 2016, 03:41 PM

Yeah, I actually came across that thread as well. However, my tank and sending unit look different that any others I could find. I don't know too much about these pieces and how they work together. So, in my eyes it's best to keep what I have if I can get it back into tip top shape.

M & J · March 28, 2016, 04:26 PM

They aren't complicated and rather simple. Since you are a full member download the GM P30 chassis manual. There is a full description on fuel delivery including when and why the in tank pump was added. Those sending units have been in fuel tanks since fuel gauges were put in dashes. The only later change was the addition of the fuel pump bracket at the bottom and additional piping for the return line and in some the generator pick up tube. The manual probably has the original GM part numbers that can be used to find a replacement if you ever have to.

BrianB · March 28, 2016, 05:14 PM

Quote from: solracem on March 28, 2016, 02:20 PM
...
It also has some walls built inside that seem like a series of doors and passage ways to prevent fuel from draining to one side of the tank.

They are "baffles" that prevent the fuel from sloshing around and starving the fuel pump when the gas is getting low and you hard brake or stomp the pedal to go.

They are the equivalent of a shock-absorber for the fuel tank.

HandyDan · March 28, 2016, 05:39 PM

I've recommended this place before. They do motorhomes and odd ball fuel senders. http://tristarrradiator.com/

Edit: Ooops, I should have read ALL the posts. Just ignore I wrote anything. LOL

M & J · March 28, 2016, 05:52 PM

Where in the heck is the delete message option on these........ lol Tristar it is.

solracem · March 29, 2016, 11:55 AM

figured for those future visitors who run into this problem, I'd post a couple of pictures.

solracem · March 29, 2016, 11:57 AM

a few more

solracem · April 05, 2016, 12:21 PM

Quote from: bluebird on March 21, 2016, 11:36 PM
It should still have 3 or 4 lines coming off the top of the tank. If it has an in tank pump it should have a regulator on the frame rail too. That regulator will probably need a new diaphragm and can be bought most any parts place that handles Holley parts. Make sure you either use the same spring that's in there or the one that's the same color in the kit. Replace all the rubber fuel lines back there also.

Hey BlueBird - What does the regulator look like? I'm not too sure I have one. However, I do have the pump. I should have the sending unit back from being rebuilt in a week and the gas tank from being cleaned later today. I want to make sure I buy the regulator diaphragm as well if I need one.

Is it this thing in the picture?

Thanks!

Rickf1985 · April 05, 2016, 12:26 PM

That appears to be some sort of ancient filter! The bracket though looks like the one that would hold the regulator and since I see the tank fill in the picture it is in the right place for the regulator. I am wondering if someone removed the regulator?! It will have four screws on a square cover with a adjusting screw coming out of the center of the cover.

legomybago · April 05, 2016, 12:51 PM

Looks like it could be some sort of check valve too/also?

?? Holy smokeys. Pull that thing off there and show us

Rickf1985 · April 05, 2016, 01:08 PM

Here is what the regulator should look like. Much dirtier and not chrome I am sure.

http://www.amazon.com/Holley-12-803-Fuel-Pressure-Regulator/dp/B00029JC6C

And when you want to rebuild it..........

https://www.holley.com/products/fuel_systems/fuel_pumps_regulators_and_filters/fuel_system_components_and_service/regulator_repair_kits/parts/12-807

solracem · April 05, 2016, 01:19 PM

Gotcha. That one sits close to the back end of the tank on the drivers side. How about this thing, is it the regulator?

Also, should i just get rid of the ancient filter?

solracem · April 05, 2016, 01:21 PM

Quote from: legomybago on April 05, 2016, 12:51 PM
Looks like it could be some sort of check valve too/also? ?? Holy smokeys. Pull that thing off there and show us

will do tonight

solracem · April 05, 2016, 01:43 PM

Quote from: legomybago on April 05, 2016, 12:51 PM
Looks like it could be some sort of check valve too/also? ?? Holy smokeys. Pull that thing off there and show us

I believe it may also be some sort of vent as I believe it was connected to the vent tube that runs to the bumper.