Hahn Water Leak

[FireRescueLupo]

We had a 1988 Hahn engine donated to us that seems to be leaking from the tank to pump line. We have not dug into it to deep yet but pulled the covers and crawled underneath to try to locate the leak. I have not worked on Hahn's at all and was wondering if anyone has any experience with them or if it is going to be the same as any other pump work, and if so how much effort are we looking at to get this fixed. My next step is to look for schematics on it and see what sort of seal there is suppose to be or if there is one better option to get this to hold water. Of course cheap is better, this is a second out pumper and might end up being a backup for us and our other stations so most of our budget is set on primary response vehicles. Any help is appreciated. Thanks.

[CaptOldTimer]

We had a 1988 Hahn engine donated to us that seems to be leaking from the tank to pump line. We have not dug into it to deep yet but pulled the covers and crawled underneath to try to locate the leak. I have not worked on Hahn's at all and was wondering if anyone has any experience with them or if it is going to be the same as any other pump work, and if so how much effort are we looking at to get this fixed. My next step is to look for schematics on it and see what sort of seal there is suppose to be or if there is one better option to get this to hold water. Of course cheap is better, this is a second out pumper and might end up being a backup for us and our other stations so most of our budget is set on primary response vehicles. Any help is appreciated. Thanks.

The name of the truck has nothing to do with the leak.

Probably a pipe may have a small hole in it from the tank to the pump. It also could be a joint is leaking.

This can happen to any pumper thak has a tank.

Also look at the pump its self, it may be a Hale, Waterous or someother. It may be the packing gland that is leaking and needs to be tighten or replaced.

[FWDbuff]

Greetings from Hahn Country.

Capt is correct. The name really has nothing to do with the leak. I am going to assume that it is due to age. 20+ years of use (going down the road, being bumped around, pressurized, etc etc etc) has finally caused a typical failure. It could happen to a Mack, an ALF, a Seagrave, etc. The tank to pump (T2P) line for the most part is usually placed in a (somewhat) accessible spot, so that it can be changed out easily. Is it a victaulic hose????

My recommendation is to remove it, and take it down to the local hose shop and have a new one made up. Pay the extra bucks and get a braided stainless line.

I am sure Chiefengineer11 may toss in some advice. He probably has more time on two Hahns (a 68 and a 78) than some Hahn engineers do.

[chiefengineer11]

Hahn built a good, solid truck (we had two) but their steel tanks were notorious for leaking. Our last one, a '78 C12 got so bad that we replaced the tank with a Custom Fiberglass tank. Among other things, the truck lost 1200 lbs. Unfortunately, I think CFP has left the scene.

If you're in a position to do it, look at the various tank manufacturers about a plastic tank. But quiz them closely and talk to their customers. I know of one that has problems breaking baffles and another that can't make required flow because of the way it's baffled.

If you're not leaking water onto the ground, check the tank to pump valve. Hahn typically used Akron valves at that position. At that age it's very likely equipped with a plastic ball. If the valve is in the position where Hahn normally used to put them, it should be very easy to rebuild. Just be sure to get a kit with a stainless steel ball.

[FireRescueLupo]

Thank you all. Yes, I should have mentioned the pump more so than the truck. Not looking at it off hand I believe it is a 1500 GPM Hale pump with a 1000 gallon tank. It seems to be a good truck. Wiring is a little jacked around but that is nothing to tough to fix, more so tracking what wire goes to what than anything. We found that it was leaking after putting some water in the tank to see what it would do. I am probably putting my money that Chiefengineer11 is right and that it might be vavle on it. I will take a look at that tomorrow. Thanks for the help.

[EastKyFF]

Don't forget the possibility of water trailing off something else and then dripping onto (and then off of) the T2P line, giving you a false impression that it is leaking there.

[FireRescueLupo]

I did not get a chance to get the valve off and open it up last night like I hoped having to prep a truck to cover for another station that has theirs out of service for a while but after closer inspection it might be both a leak within the valve t2p and the seal between the t2p valve and the line to the pump. Even with the pump dry water was running into the pump and also leaking from the area were the valve threads to the line to the pump. I dont think this was the first time this has happened or they may have used this procedure in the past but there appears to be plumbers tape wrapped around the threads there.

[CaptOldTimer]

I did not get a chance to get the valve off and open it up last night like I hoped having to prep a truck to cover for another station that has theirs out of service for a while but after closer inspection it might be both a leak within the valve t2p and the seal between the t2p valve and the line to the pump. Even with the pump dry water was running into the pump and also leaking from the area were the valve threads to the line to the pump. I dont think this was the first time this has happened or they may have used this procedure in the past but there appears to be plumbers tape wrapped around the threads there.

Remove the valve and the tape. Put some plumbers dope on the threads once you've cleaned it good and reinstall.

[LVFD301]

If you're in a position to do it, look at the various tank manufacturers about a plastic tank. But quiz them closely and talk to their customers. I know of one that has problems breaking baffles and another that can't make required flow because of the way it's baffled.
.

As I am specing a new tanker, I don't supposed you would PM me off the record with a little more info on this.... Please...

[chiefengineer11]

As I am specing a new tanker, I don't supposed you would PM me off the record with a little more info on this.... Please...

System won't let me PM you. Try me at chiefengineer11@verizon.net

[chiefengineer11]

I did not get a chance to get the valve off and open it up last night like I hoped having to prep a truck to cover for another station that has theirs out of service for a while but after closer inspection it might be both a leak within the valve t2p and the seal between the t2p valve and the line to the pump. Even with the pump dry water was running into the pump and also leaking from the area were the valve threads to the line to the pump. I dont think this was the first time this has happened or they may have used this procedure in the past but there appears to be plumbers tape wrapped around the threads there.

I'm holding to my guess that you have an Akron valve. Hahn normally took a 2-1/2" or 3" line from the bottom of the tank, through the valve and into a port on the steamer inlet casting. That was before direct tank inlets on the back of the pump were commonplace. If it's as I think it is, the valve is normally repaired by undoing the bolts that hold the body to the flanges. The flanges are threaded to the pipes and normally aren't removed. They may well have been there since the truck was built.

What does happen is that over years the pipe corrodes around the threads and eventually a leak develops. What you are describing may very well be just that. If it is, you'll need to replace the pipes also. That's not such an easy task.

[FireRescueLupo]

That sounds about what it looks like. I hope we do not have to replace the pipes but I will check that out. T2P comes in on the driver side from the bottom of the tank and I belive it may run into the steamer pipe. Going off of memory but that would make sense. Thanks for the help.

[ffp20]

Hahn built a good, solid truck (we had two) but their steel tanks were notorious for leaking. Our last one, a '78 C12 got so bad that we replaced the tank with a Custom Fiberglass tank. Among other things, the truck lost 1200 lbs. Unfortunately, I think CFP has left the scene.

If you're in a position to do it, look at the various tank manufacturers about a plastic tank. But quiz them closely and talk to their customers. I know of one that has problems breaking baffles and another that can't make required flow because of the way it's baffled.

If you're not leaking water onto the ground, check the tank to pump valve. Hahn typically used Akron valves at that position. At that age it's very likely equipped with a plastic ball. If the valve is in the position where Hahn normally used to put them, it should be very easy to rebuild. Just be sure to get a kit with a stainless steel ball.

Notorious is a kind word for it. Among numerous leaks, I had a '75 with a 4" rear discharge run through the tank that sprung a leak. we noticed when someone removed the discharge cap tons of rusty water would pour out, and, when running the rear discharge, we'd overfill the tank. That was a b***h of a repair too.

[frank23]

Tank leaking can be repaired by professional plumbers as they have nkowledge and experiance regarding these problems. But small leakage can be overcome with some kind of glue.



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