So I thought I would post this for all those out there like me that aren't running a re-flash or more boost...yes I am still running stock with accessories which works for me. But at the end of last season I took a quick ride on the wife's sled before putting it on the trailer and my butt dyno told me it had more scoot than mine. I performed all my preseason checks and adjustments and after much thought decided I would spend the money and buy a Boost Leak Detection Tool.

So today was the day, hooked it up to the wife's sled and all seemed good...then I hooked it up to mine and holy crap I had a massive leak, I took the seat and tank off (actually pretty easy) and as many others have found my leak was at the reference connection to the throttle body. Replaced the cheap ass factory single wire clamp with a worm gear clamp, I also found a few other loose clamps and small air leaks. Once I was done with mine I took hers apart and replaced her a little better double wire clamp with a worm gear clamp. Hers also had some loose clamps and small leaks. Now both sleds hold pressure as they should.

I really didn't expect to find such a large leak, I recommend everyone even you fellow stock guys pickup a tester and check your sleds. I bought mine from Precision Sports and it is a very high quality tool.

Now that I have the proper tester this will be part of the pre-season and mid-season maintenance routine.

Thanks Martin

x2^

Every FST built will leak at that left intake barb within one season. If left as is the leak will get worse over time. Your butt dyno will be happy next ride.

Humor me here please. 2 weeks ago I tested my referance lines, put 20-22 psi in the system between the turbo and intercooler and it takes about 20 seconds till I am at 10 psi. Cant find any leaks is this ok or am I not finding a leak or is it just going by the rings, any thoughts on this would be nice. Thanks

That would be considered ok. Not perfect but not bad either. If you ever take the fuel tank off do the check again and look closely at the left intake barb.

I used a spray bottle with soapy water and squirted every hose and connection to check as I too was losing pressure thru the engine. Worked good as I found some leaks.

When I do the boost circuit leak down test I also apply 20 psi between the turbo and intercooler. After 1 min, I have 10 psi. During the 1 min test I don't hear any leaks or gurgling.

I made my own pressure tester using a 2 3/4 inch plumbing pipe cap and a tire valve.

Note: I had leak at ref hose.

that is an awesome idea.i ll have to try that this weekend

Glad you found the tool was useful. You got the newer version for 2011-2012 which is an evolution from the one I was selling last year.

There is no need to pressurize to intake circuit more than 15psi. As a general rule of thumb, if there is no air leak to be heard.... then all is good. As Snobeeler was saying, 99% of all FST's and turbo sleds leak from the factory and the situation gets worst over time.

An innexpensive tester can be made quite easily... and it is worth spending time building one. If you have no time or would rather get a professional tool... then there is the one I offer. One thing is certain, if you have not tested your sled for air leaks, then chances are (and I mean 99% chances) that you are down on power a solid 20hp. The reason is the most common leak is at the reference line signal source -- this prevents the Blow Off Valve from sealing completely while under boost and the engine is venting turbo pressure into the open atmosphere, this makes the turbo work overtime to compensate for the lost pressure and it makes it less efficient and much less durable.

Mine was very loose at left intake, i could wiggle side toside and pull on off without loosening my clamp, i replaced with 1/8 hose and new clamps, EVERONE should do this.

So when i try to pressurize between intercooler and turbo all it does is blow out through the air filter. so i plegged that off and put pressure to it and it would blow that cap off every time. What am i doing wrong? I am new to this fst stuff so please bear with me! Thanks guys.

You put pressure in the large hose that goes into intercooler. You have to temove the hose at the Turbo outlet and leave it attached at intercooler.

To test the sytem, take the hose off the turbo which leads to the intercooler. Pressurize that hose and you'll have the system presuurized. The turbo and airbox will not be pressurized, but the intercooler, hoses, boost box reference lines will be. Anyone have a photo handy of the Boost Leak Detection Tool installed on the sled handy?

Here is one.
Click to view attachment

thanks guys! I get it pressurized to 20 psi and it slowly goes back down to 0, i cannot hear any leaks anywhere and have gone around and tightened every hose that i can see. I need more help, sorry. what next?

Use the soapy water with squirt bottle and spray all lines and fittings and boost box. Look for bubbles. If none, than listen to engine and rotate by hand to make sure valves are sealed.

At what point are you going to tell us what is wrong with your sled? Cant help if we dont know the symptoms.

Theres really nothing wrong, i was putting my tunnel protectors on today so while i had my tank off i figured i would try and do the boost leak test. Now that i have done it, it seems to loose pressure very slowly, i was wondering if it should stay pressurized at 20 psi when i pressurize it or is it normal for it to gradually go down. I did the soapy water test and i cannot find any air bubbles anywhere. I just hope that im checking all the right line. I even replaced all spring clamps with worm drive clamps. Thanks for your time guys i really appreciate it. Im new to 4 stroke and just want to learn!!

If it's slow, you are good to go. It will not hold a steady pressure as it will leak past internal engine parts.

Awesome! Thanks for all the replies, i appreciate it!!

Here is a great vid that walks you through building your own leak tool.

http://www.youtube.com/watch?v=u3Kqh52PC6Q

I agree, the valves are not perfectly clean, especially after sitting over summer. I usually accept 4 PSI drop max per minute as long as no external leaks can be heard or found with soapy water.. If you're in this range, you're good.

K guys i built my own boost leak tool, now when i pressure it up to 15-20 psi i can hear bubbles in my oil resuvior and it actually pushed oil out of my turbo. So oil is dripping from my turbo. What does any of this mean?

Help?

during the leak test rotate the primary until no air is evident in engine

thats normal if you presuureize the turbo to .i just connect after the turbo , to the inlet side of innercooler.

Once again, thanks guys! The turbo is good to go!

It means you didn't follow the directions for testing for leaks. Sorry, I couldn't resist. Glad to hear all is well.

SNOBEELER, where were the directions? That probably would help!!

finally approved my account and able to reply on here. thank god i found this site because if i didnt i would have sold my fst all ready. you all saved me

i made my own boost pressure guage(tested my setup to make sure my new tool wasnt leaking) and tried it out. i had leaks everywere and till i finally got it to hold pressure. i aired it up to 20 pounds(seems what everyone else does on here) and is slowly drops off over a minutes time it drops down to 14 psi. then over the 5 minutes it drops completely. is this normal or should it hold a consistant pressure? it sounds like its going past the rings and ive rotated the motor a bunch to see if it makes a difference. also if it matters i also havent started this sled yet since taking it out of storage 2 months ago. i used windex on all the reference line fittings and round the throttle bodies, intake, and the rest of the hoses. no more leaks that i could find

so is this normal or should i keep diggin into it?

agian thanks everyone on here!!

This sounds okay. As long as you don't hear any external leaks. It will not hold constant pressure.
Welcome!

Welcome deerhunter!

It sounds like you found your leaks. Your test now seems like normal leak free results.

Post #13 in this thread. No biggie.
Edit, I thought you were pressurizing the turbo inlet. I get bouncing around on here and sometimes forget what was posted by whom.

My plan was to test from the turbo inlet with the turbo oil line removed and a nut placed where the banjo fitting goes.
That would stop air from going backwards into the oil system.
I havent got around to firing up the lathe to do it yet but my thinking was it would be a lot easier to get at that way.
Am I missing something here?

Make sure you check the left intake on the throttle body, the hose is too big for the barb and can't be tightened properly, our clan has 3 fst's and 2 of them were leaking here.

Nevermind! Forgot about the oil drain on the turbo

Anyone have pics of the reference connection at the throttle body? I'm new to FTSs' and I'd like to check the '07 I just bought (1600 miles), but I have no idea what I'm looking at. I take the seat and tank off then what?
Thanks, Guys.

You can check it by just removing the air filter box but if you want to replace the line you will have to remove the seat and gas tank to get your hands in there.
You will see a t fitting there with small clear tubing.
There is a short line going from the T down to the left intake between the throttle butterflies and the engine.

Will be digging through the new sled. And sounds like some clamps should just be replaced. Has any one used a constant tension clamp instead of worm drive clamps? These are used primarily for pressurized lines.

Also a little trick I've learned with my 6.0 powerstroke is to spray your connection points down with hair spray. Provides a sticky base and prevents your hose from sliding back and blowing off.

I have not dug into it yet. But what size are the tubes?

Most of the guys on here use oiteker clamps on the boost box and throttle bodies, there is threads here about these clamps, for your boost reference lines if i were you i would get some 1/8 hose and a new tee and replace all of them, then use zipties or some small clamps to finish them off, MAKE SURE you have a good look at the short hose going back from the 3 way tee to the left throttle body because mine was litterally falling off, good luck.

Worked on it today and did notice a few that were loose. Will pick up some clamps to put on them.

Hi Snobeeler,
Using Precision Sports boost leak testing tool, we found the same leak on our 3 x FST. Spoke to Martin and we used a 1/8 ID windshield washer hose from that left intake to the T fitting. No more leak!

Its amazing Poo still uses that wrong size barb after all these years. I keep preaching every FST will encounter that problem someday. I guess they dont read this forum anymore.

Which size is the hoses/intake? 2,5"? I would go out and measure myself, but it's cold today!

TurboBoostLeakTesters.com seem to supply some rather decent/cheap boost leak testers. And they use ebay for orders.

I built mine for about 25 dollars. Cheap enough!

MCKFUSE:
Unfortunatly for me, I think the parts alone is a whole lot more than the 30 bucks + transport.

I got my tool delivered, I ordered the 2,25" from turboleaktesters.com. The rubber was useless, but the plastic pipe where the nozle and gauge was fitted fit perfect into the pipe. After spending some evenings clearning the clutch side and changing spark plugs (phew), I finally have gotten to test for leaks.

0-5 psi seems to hold well
5-10 psi slithly worse, and leaking sound from turbo
10-15 psi holds at a rate of 0.5 psi/sec

I'm preasurizing after the turbo, and I was surpised to find that the leaking sound I heard was oil being pushed out of the turbo. I'm struggeling to comprehend whats happening, and if it's expected or a bad sign. Anyone got a clue?

So is 2. 25" the right size for the hose after the turbo?

i wouldn't worry to much, that can happen when there is no oil pressure present.