What are the symptoms of a leaking PFP chamber?

[Desk_jockey]

I understand that early batches of PFP pipes had the internal chamber crack. Mine was purchased late last year so I was thinking it was an updated design but I dont really know.

My ski started running really funny lately and I think it is due to water flow. Was running perfectly before this. The ski loads up really bad just idling around and it feels like excessive water in the exhaust. I can braap it out and it cleans up and runs great again until coming back to idle for a few seconds. It feels like there is so much water in the exhaust that it makes the engine stumble really bad before it will clear out. The water restrictor is set to mostly closed and that is where it has been for the last year.

The really strange thing is when riding nose high, ski will barely run. It feels like water is running back into the manifold or something.

So, what are the symptoms of a cracked chamber? Also, I was thinking perhaps my exhaust gasket went bad? I did get the engine hot right before this started happening when my strainers pulling in a bunch of sand.

 

[Jcary85]

That all sounds like it could be a cracked pipe. It’s easy to test. Cap two of the lines and pressurize the other. it should hold 10 psi forever. A bike pump or pop off tester works well. You can do a similar test on the motor. Cap lines on manifold and one on the head and pressurize to 10 psi.

 

[clouse22]

Yes pressure test the chamber as stated above. Thats the easiest way to tell if it is broke.

Also if you pull the chamber and a bunch of water comes pouring out from the inside you know its broke.

In theory the ski should run just fine on a shop stand if the chamber is broke without water going through the system.

Id say your chamber is definitely broke through with your flow control being closed.

 

[Desk_jockey]

Going to try pressure testing the chamber and the engine tonight. It runs great on the stand and also once all the water is braaped out while in the lake.

 

[kevbo]

A tiny exhaust leak inside the hull can do this. A quick and dirty test is riding without the hood to see if it changes.

 

[Desk_jockey]

Checking for an exhaust leak is a good mention but I am pretty sure my pipe is cracked. Double check my work here. I blocked off the middle and under stinger fitting and used my pop off gauge to test at the head end. Wouldn't register more than 2 psi furiously pumping and I can hear leaking inside the chamber. Just to be sure, I filled the chamber with water and stood it up and repeated. Bubbles are coming up from inside chamber.

Dang. What do I do now? I really don't want to convert this to a wet pipe. Who can fix this?

 

[Jcary85]

Checking for an exhaust leak is a good mention but I am pretty sure my pipe is cracked. Double check my work here. I blocked off the middle and under stinger fitting and used my pop off gauge to test at the head end. Wouldn't register more than 2 psi furiously pumping and I can hear leaking inside the chamber. Just to be sure, I filled the chamber with water and stood it up and repeated. Bubbles are coming up from inside chamber.

Dang. What do I do now? I really don't want to convert this to a wet pipe. Who can fix this?

I’ve fixed two now. It’s not hard if u can TIG weld. If u wanna send it to me I’ll weld it up for ya for a case of beer or something.

 

[Storbeck]

I’ve fixed two now. It’s not hard if u can TIG weld. If u wanna send it to me I’ll weld it up for ya for a case of beer or something.

Were the two you fixed both cracked in the same place?

 

[ErieOne]

I found a local welder to fix mine but you have to be specific about exactly where the leak(s) are.


Sent from my iPhone using Tapatalk

 

[iQRTurbo]

Chambers are a 30 second test and only requires a screw driver to pull two of your 3/8 lines. Remove the first two hoses ( water feed in and water out to stinger)
Put a piece of hose on the water in and blow on it with your mouth while putting your thumb over the overboard pisser and the water out to the stinger. You have basically capped two and pressurized the third. It will immediately be evident if it leaks. You won’t be able to blow into a solid chamber, if it’s cracked you will hear it hiss inside and it will pass air easily through the hose. Works every time and is literally a 30 second test
Every chamber I have seen cracked (I’ve fixed about 7 or 8) has been broken around the plug weld where the two skins are welded together on the outer radius of the pipe belly. Inner chamber cracks around the perimeter of the weld.

 

[Jcary85]

Were the two you fixed both cracked in the same place?

The two I fixed were both cracked around different plug welds. Mine was cracked at both plug welds in the middle of the pipe. My friends was cracked at the plug weld closest to the stinger. They seem to last longer once fixed.

 

[Desk_jockey]

Jscary85, sent you a pm.

It's hard to tell exactly where it is leaking but I am guessing it's around the factory standoff welds.

 

[Desk_jockey]

Just wanted to give a shout out to @Jcary85 for repairing my PFP chamber for me. Much appreciated!

 

[McDog]

I only run these wet now for this reason. I thought my carbs were getting wonky and kept leaning it out to compensate until i melted a piston once because of a leak.

 

[Desk_jockey]

Yea, I figured I will give it one more shot. Pretty sure I overheated it the first time by running with clogged strainers, so I removed those. We will see . . .

 

[cpolaris502]

In my case last year, the symptom of leaking was a bent connecting rod on my 2hr old (to me) 1105. Fresh ski build so I wasn't sure how it was "supposed" to run. As it sat on the beach stand, the water jacket leaked back into the manifold and cylinder. You can guess what happened when I went to fire it up. Ouch.

 

[Freakrider]

Nobody knows when these PFP chambers will start leaking, perhaps pulling ski up on the beach stand backwards and then braaping out chamber before reloading is words to the wise to prevent above scenario.