Iīm in the process sealing my gas tank with POR 15. Its a cowl tank. Just thought you would like to see the baffles and the half moon shaped holes. I know there has been some demands regarding photos of the inside of this type of tanks. The holes are pretty big approximately 2 inch diameter .There are three holes between the first chamber and the second [no. one is under the filler hole. One in each lower corner and one in the middle. Between no two and three there is one hole in the middle and the big circular hole in the centre Its plenty of space for the drywall screws to pas thru. Here are some nasty photos.
Nasty. Think I would find another gas tank.
If you fasten it to a tractor wheel and drive for a while - or wrap it in a blanket and put it in a cement mixer for a few hours, then all the loose rust will be gone and you can test if there are any leaks to solder..
Beware of coating with anything if not absolutely necessary - nasty components in modern gas has a tendency to make a gummy mess out of coatings..
Yepp. Did the cement mixer trick .
I did the coating thing once. Never again.
Richard. Yea, it looks awful inside. Plenty of rust and gunk, but there are no pinholes, and the baffles are tight. Since I live in Sweden, its impossible to get a better tank here. If i buy one from US, it canīt be sent by air since its hazardous. I think I have to do with the one I got.
If all the loose rust is off and there are no pinholes, then there's no need to coat it - it won't rust any more when it's in use and filled with gas.
U r between a rock and a hard spot.
I have had good luck coating tanks. Model T and Honda mot o recycle tanks. Never had one leak or get rust in the carbs. Just lucky I am sure. I do not coat car tanks anymore. I would rather finally one in good shape. Sometimes that is tough though. Tim
I have used the POR gas tank sealers many times with not one single failure. But you "MUST" do a thorough cleaning and follow the directions, The dry wall screws and tumbling till clean is how we do it as to the pre cleaning, We count 100 screws going in and 100 screws coming out... Then you should use the "marine clean" that is part of the POR kit. It cleans out any remaining carbon based oil, or gas residue. Then you use the acid etch that is also part of the POR kit to remove any remaining rust. Give the products time to work. After rinsing the tank out, it will have a slightly acidic surface for the sealer to bond to. Then take a hair dryer and dry the tank very well. When you think you have it dry "dry it some more" Then have a Coke or coffee before you start to slush the tank ... Then "dry it some more" ... Did I mention that the tank "must be dry as a bone in the desert". Then plug the drain/outlet hole, and pour in the slush compound. Put on the cap and start to rotate the tank to every position you can think of to spread the sealer compound everywhere. This should take 15 to 20 minutes, as you want to make sure the baffels are covered as well as all seams. When you think you are done, rotate it a little longer. Then remove the drain plug and drain out all the sealer you can. Now comes the fun part. You do not want the sealer to puddle up in the bottom. So for the next 3 to 4 hours (or longer depending on humidity) you need to keep moving the tank to different positions. You can look thru the filler hole and see the remaining sealer "creep" I watch it and try to make it run and seep around the seams as I am spending the 3 to 4 hours of watching and monitoring the sealer. You can also speed up the process by blowing air from your blow dryer with "no heat" "just air" into the tank. It is a lot of work and time consuming to do it right. But the 26 27 gas tanks are not being reproduced, and the days of nice, useable as-is tanks being easy to find, are a thing of the past. For the regular round and oval tanks it is cheaper and easier to just buy a new one. But the 26-27 tanks, are a "fix what you got" type of deal. So slushing them is a good fix. Between myself and my buddy who has a body shop. We have slushed at least 25 to 30 tanks using POR gas tank sealer kit. Not one single failure yet. Some of our first slushed tanks may be 15 years older by now. I can not vouch for any of the other brands of sealers, but I have heard some horror stories about them ... Good luck with your project .... Have fun and be safe ....
I hear there is a man in Texas that takes the 26/27 tanks apart, cleans and repairs any leaks. Is there such a person and how do I reach him? Thanks in advance. Bob
When I seal a tank the first step is to dry it out and then whack it all over with a rubber mallet and that will pop a lot of the rust loose that tumbling might not get, you will be surprised at how much it breaks loose and the size of the flakes.
I think you are talking about Lilleker Antique Auto Restorations.
The reason for posting was primarily to show what the baffles and holes between the three sections looks like. It has been a demand for pictures recently. Regarding the drywall screws, I put in about 30 oz. The amount and weight of that many screws makes the rust removal more efficient. I found the removal of the screws quite easy. No place fore the screws to get stuck. Thanks Donny fore your detailed advise. That's exactly the way I'm going to do the process. I bought the complete kit. I'm confident the result will be great, and my biceps a bit bigger.
Should be Donnie, not Donny. Sorry.
A big 10-4 on the POR-15 here too!
Pictures are a little too close to see what they are. Here's one of the entire tank taken a little further back. Jim Patrick
Yes Jim Patrick. That photo is well known. But I have never seen the holes in the baffles , how many and how they are located. That's why I took some pictures with the endoscope.
For those who are in the process of relining their cowl tank it might be of interest.
Someone sealed the tank in my 27 before I got it, They must have done a very good job because I have had no problems with it.
With your knowledge of the tank internals can you tell me if it's possible to have no fuel flow to the carburettor even though the dipstick will show some fuel in the tank? Is there a minimum level needed for flow? ie is the sediment / valve located at the bottom most point of the tank or baffles stopping fuel movement at low levels.
Alan in a Western Australia
Alan. There should be no restriction inside the tank preventing all of the fuel to drain out trough the outlet/sediment bulb. If the car is on level ground,that is. It might however have been made some modification to the outlet by someone, to prevent the rust in the bottom of the tank to drain . Remove the bulb and see what's going on.
I can report that my treatment with the POR15 kit have turned out great. The tank is like new. I followed the instructions carefully. It was a tiresome work that took a week. But it was worth it.
Use Muriatic acid, I just used it works great!
I think rust removal with muriatic acid ,vinegar dishwasher cleaner and gravel or drywall screws is a god way to get rid of the rust. The important thing is to prevent the tank from starting to rust again once its clean. That's why I sealed it. There is some good sealers on the marked, I choose POR15 because of good feedback. The kit consists of marine cleaner, metal prep that turn the remaining rust to zinc phosphate witch will allow for better adhesion of the POR15 sealer.