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Air Leak Advice
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AcroGimp

Joined: 11 Jun 2013
Posts: 45
Location: San Diego, CA USA

Posted: Sun Mar 29, 2015 7:26 am Post subject: Air Leak Advice

New owner, had plane for about 2 months now.



I noticed that while in flight the air was not really pumping up, I suspected maybe an up-lock so I tried isolating the system by going to neutral on the FWD gear handle for the past couple flights and it now pumps up to about 50 ATM just fine.  



While on the ground it does not seem to make up air either (even at 60-70%) - is it possible/recommended to isolate the system when on the ground assuming the Gear lock slide is in place? Or does it just take more time to pump up than I am either patient for or for which CHT allows?



Before I call in the mechanic I would like to try and troubleshoot further and am looking for suggestions on the most likely things to check first, and any other recommendations.



Thanks in advance.



'Gimp

_________________
Owner/Pilot N6209F 1987 Yak-52
COMM/ASEL/IFR/HP-Complex/TW

AcroGimp

Joined: 11 Jun 2013
Posts: 45
Location: San Diego, CA USA

Posted: Tue Mar 31, 2015 9:06 pm Post subject: Re: Air Leak Advice

So new development at the hangar today.  Main system had leaked down from 3.5 to 1.5 since Saturday afternoon - which had not been observed before.



Been through the search function and am learning a bit but not able to figure next bit out so asking for help.



While in the cowling I bumped the snot valve and it released a good bit of air - I am very sure, although not 100% sure, that I had cycled the snot valve on shutdown like normal on Saturday, so it should not have been pressurized from the previous run.  The main air valve was OFF and had been since Saturday.



An hour later for my curiosity the snot valve was cycled and again released some air (I had turned Main air ON to drop the flaps for an unrelated check while installing a wing step) - it was OFF at the time.



Possibly related, I know I have a slow leak on the Emergency side, just not sure where yet (suspect the tank itself based on troubleshooting for previous owner).



Currently thinking PRV and/or Snot Bottle.....



Ideas?  Suggestions?



'Gimp

_________________
Owner/Pilot N6209F 1987 Yak-52
COMM/ASEL/IFR/HP-Complex/TW

LawnDart

Joined: 05 Jun 2006
Posts: 64

Posted: Wed Apr 01, 2015 5:25 am Post subject: Re: Air Leak Advice

1) Main system leak - follow the line from the snot bottle to the air check-valve tee on the firewall.  The first check valve after the snot bottle is not seating properly.  This will need to be removed (removing entire tee is best) and cleaned.



2) Emergency system leak - most likely the square "o-ring" in one of the emergency release valves in one of the cockpits.

AcroGimp

Joined: 11 Jun 2013
Posts: 45
Location: San Diego, CA USA

Posted: Wed Apr 01, 2015 6:26 am Post subject: Re: Air Leak Advice

 	  LawnDart wrote: 	
		  1) Main system leak - follow the line from the snot bottle to the air check-valve tee on the firewall.  The first check valve after the snot bottle is not seating properly.  This will need to be removed (removing entire tee is best) and cleaned.



2) Emergency system leak - most likely the square "o-ring" in one of the emergency release valves in one of the cockpits. 	
Thanks, I can check that tomorrow afternoon.



What is recommended cleaning approach for check valve and snot bottle (I am going to hit it anyway since I am not sure when it was last done)?



'Gimp

_________________
Owner/Pilot N6209F 1987 Yak-52
COMM/ASEL/IFR/HP-Complex/TW

LawnDart

Joined: 05 Jun 2006
Posts: 64

Posted: Wed Apr 01, 2015 6:37 am Post subject: Re: Air Leak Advice

I would just clean them with kerosine or avgas.

The hiccup will be getting the check valve disassembled.  They can be tough to get open after time.  Once you do, it is a simple device and you'll figure it out.



BTW, if you notice a leak from the fill port, the issue will be the other check valve on the tee.



On the emergency side.  You will have to remove a side panel to gain some access - then place a soapy water around the tee fitting at the bottom of the valve rear cabin).  If it is leaking it is the square o-ring.  If not, move on the the front cabin valve and apply soapy water.

dsavarese0812(at)bellsout
Guest

Posted: Wed Apr 01, 2015 6:39 am Post subject: Air Leak Advice

You could very well have actuator leaks. With the gear selector down in 

the front cockpitand the rear gear selector in neutral, open the main 

air valve and listen for an air leak at the front gear selector.



Assuming you hear the "hiss" at the front gear selector, you will now 

have to isolate which actuator is leaking.  You will need to remove the 

90 degree elbow on the bottom end of the actuator (the end closest to 

the chrome shaft) and place your finger over the male 90 degree fitting 

with the main air turned on.  If the actuator is leaking, you willfeel 

and hear the air coming out of the 90 degree fitting.  If the first one 

you check is ok, move to the other two.



Let me know what you find and I will do my best to help you troubleshoot 

the system.

Dennis



A. Dennis Savarese

334-546-8182 (mobile)

www.yak-52.com

Skype - Yakguy1



On 4/1/2015 8:25 AM, LawnDart wrote:

 	  Quote: 	
		   



 1) Main system leak - follow the line from the snot bottle to the air check-valve tee on the firewall.  The first check valve after the snot bottle is not seating properly.  This will need to be removed and cleaned.



 2) Emergency system leak - most likely the square "o-ring" in one of the emergency release valves in one of the cockpits.





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=440141#440141

AcroGimp

Joined: 11 Jun 2013
Posts: 45
Location: San Diego, CA USA

Posted: Wed Apr 01, 2015 6:52 am Post subject: Re: Air Leak Advice

 	  dsavarese0812(at)bellsout wrote: 	
		  You could very well have actuator leaks. With the gear selector down in 

the front cockpitand the rear gear selector in neutral, open the main 

air valve and listen for an air leak at the front gear selector.



Assuming you hear the "hiss" at the front gear selector, you will now 

have to isolate which actuator is leaking.  You will need to remove the 

90 degree elbow on the bottom end of the actuator (the end closest to 

the chrome shaft) and place your finger over the male 90 degree fitting 

with the main air turned on.  If the actuator is leaking, you willfeel 

and hear the air coming out of the 90 degree fitting.  If the first one 

you check is ok, move to the other two.



Let me know what you find and I will do my best to help you troubleshoot 

the system.

Dennis



A. Dennis Savarese

334-546-8182 (mobile)

www.yak-52.com

Skype - Yakguy1



On 4/1/2015 8:25 AM, LawnDart wrote:

 	  Quote: 	
		   



 1) Main system leak - follow the line from the snot bottle to the air check-valve tee on the firewall.  The first check valve after the snot bottle is not seating properly.  This will need to be removed and cleaned.



 2) Emergency system leak - most likely the square "o-ring" in one of the emergency release valves in one of the cockpits.





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=440141#440141





	
	
Thanks Dennis, I just sent you an e-mail but for the benefit of other operators I will keep this thread going.



Thanks



'Gimp

_________________
Owner/Pilot N6209F 1987 Yak-52
COMM/ASEL/IFR/HP-Complex/TW

Viperdoc

Joined: 19 Apr 2014
Posts: 484
Location: 08A

Posted: Wed Apr 01, 2015 7:00 am Post subject: Air Leak Advice

Replace your check valves on the fire wall. All three of them. Otherwise you are throwing a bandaid on it. You are leaking back through the check valve (s). Open them up and they will look like shit if you can get them open without touching them. Heating them will finish off the decayed rubber for sure. The CJ valves will work from Doig Sapp (509-826-4610)  or can get them rebuilt by George Coy (802-659-0129) using US standard air system supplies from I forget off the top of my head ( Parker). CRS is a bitch sometimes.

Doc



Sent from my iPad



 	  Quote: 	
		   On Apr 1, 2015, at 12:06 AM, AcroGimp <jlknolla(at)aol.com> wrote:

 

 

 

 So new development at the hangar today.  Main system had leaked down from 3.5 to 1.5 since Saturday afternoon - which had not been observed before.

 

 Been through the search function and am learning a bit but not able to figure next bit out so asking for help.

 

 While in the cowling I bumped the snot valve and it released a good bit of air - I am very sure, although not 100% sure, that I had cycled the snot valve on shutdown like normal on Saturday, so it should not have been pressurized from the previous run.  The main air valve was OFF and had been since Saturday.

 

 An hour later for my curiosity the snot valve was cycled and again released some air (I had turned Main air ON to drop the flaps for an unrelated check while installing a wing step) - it was OFF at the time.

 

 Possibly related, I know I have a slow leak on the Emergency side, just not sure where yet (suspect the tank itself based on troubleshooting for previous owner).

 

 Ideas?  Suggestions?

 

 'Gimp

 

 --------

 Owner/Pilot N6209F 1987 Yak-52

 COMM/ASEL/IFR/HP-Complex/TW

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=440125#440125

_________________
Viperdoc

dsavarese0812(at)bellsout
Guest

Posted: Wed Apr 01, 2015 9:34 am Post subject: Air Leak Advice

If the check valve on the right side of the cross which goes to the snot 

bottle is not closing, all you have to do is open the snot bottle and 

the air from the main air tank will continually bleed out through the 

little tube on the bottom of the snot bottle. Ifyou spray soapy water on 

the external air fill port and you see it bubble, the check valve on the 

left side of the cross is remaining open and the main air bottle will 

bleed out through the external air fill port.



If themain air is solid and the emergency air is bleeding off, the first 

place to go is the external air fill port again and spray soapy water on 

it.  If it bubbles, the check valve just inside the fuselage by the 

external air fill port has some junk in it.



Dennis



A. Dennis Savarese

334-546-8182 (mobile)

www.yak-52.com

Skype - Yakguy1



On 4/1/2015 9:59 AM, Roger Kemp wrote:

 	  Quote: 	
		   



 Replace your check valves on the fire wall. All three of them. Otherwise you are throwing a bandaid on it. You are leaking back through the check valve (s). Open them up and they will look like shit if you can get them open without touching them. Heating them will finish off the decayed rubber for sure. The CJ valves will work from Doig Sapp (509-826-4610)  or can get them rebuilt by George Coy (802-659-0129) using US standard air system supplies from I forget off the top of my head ( Parker). CRS is a bitch sometimes.

 Doc



 Sent from my iPad



> On Apr 1, 2015, at 12:06 AM, AcroGimp <jlknolla(at)aol.com> wrote:

>

> 

>

> So new development at the hangar today.  Main system had leaked down from 3.5 to 1.5 since Saturday afternoon - which had not been observed before.

>

> Been through the search function and am learning a bit but not able to figure next bit out so asking for help.

>

> While in the cowling I bumped the snot valve and it released a good bit of air - I am very sure, although not 100% sure, that I had cycled the snot valve on shutdown like normal on Saturday, so it should not have been pressurized from the previous run.  The main air valve was OFF and had been since Saturday.

>

> An hour later for my curiosity the snot valve was cycled and again released some air (I had turned Main air ON to drop the flaps for an unrelated check while installing a wing step) - it was OFF at the time.

>

> Possibly related, I know I have a slow leak on the Emergency side, just not sure where yet (suspect the tank itself based on troubleshooting for previous owner).

>

> Ideas?  Suggestions?

>

> 'Gimp

>

> --------

> Owner/Pilot N6209F 1987 Yak-52

> COMM/ASEL/IFR/HP-Complex/TW

>

>

> Read this topic online here:

>

> http://forums.matronics.com/viewtopic.php?p=440125#440125

>

>

flier

Joined: 09 Jul 2007
Posts: 25

Posted: Sat Apr 04, 2015 2:43 pm Post subject: Re: Air Leak Advice

I have a little different situation on a '52 where the emergency bottle won't fill from the compressor but can be charged externally.  Main system is fine.  Also has a very slow emergency leak.  Blocked check valve?  Located where?

dsavarese0812(at)bellsout
Guest

Posted: Sat Apr 04, 2015 3:11 pm Post subject: Air Leak Advice

The emergency bottle can ONLY be filled from the external aid fill port on the Yak52. Unlike the CJ which IS refilled by the compressor as well as the external air fill port. 

Dennis



On Apr 4, 2015 5:43 PM, flier <flier(at)sbcglobal.net> wrote:

 	  Quote: 	
		  

 



 I have a little different situation on a '52 where the emergency bottle won't fill from the compressor but can be charged externally.Â  Also has a very slow leak.Â  Blocked check valve?Â  Located where? 





 Read this topic online here: 



 http://forums.matronics.com/viewtopic.php?p=440281#440281

flier

Joined: 09 Jul 2007
Posts: 25

Posted: Sun Apr 05, 2015 4:59 am Post subject: Re: Air Leak Advice

Thanks Dennis.  All this time I thought the emergency was also being replenished but I just looked at the schematic.  I'll be darn.  Appreciate the reply.

mark.bitterlich(at)navy.m
Guest

Posted: Mon Apr 06, 2015 7:10 am Post subject: Air Leak Advice

On the 50 it also is filled from the compressor.



Wouldn't be too hard to change.   I've always been curious why the Russians decided to fill it (from the compressor) on the 50 and not on the 52.



Mark

--

jan.mevis(at)informavia.b
Guest

Posted: Mon Apr 06, 2015 8:27 am Post subject: Air Leak Advice

One of the reasons could be that the emergency bottle on the 52 gets

filled with perfectly dry air, from an industrial bottle.

So less probability of oxidation etc.

The water separator on the 50 can't do better than that.

I had to replace the water separator on my 50 almost immediately when I

bought it 10 years ago.

It was supposed to be overhauled in 2000 in Shakthy.

But I'm sure that they kept the original water separator from the eighties.

I still have it, I can simply blow through it without any effort.



Only an educated guess,



Jan



On 06/04/15 17:09, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:



[quote]

<mark.bitterlich(at)navy.mil>



On the 50 it also is filled from the compressor.



Wouldn't be too hard to change.   I've always been curious why the

Russians decided to fill it (from the compressor) on the 50 and not on

the 52.



Mark

--

mark.bitterlich(at)navy.m
Guest

Posted: Mon Apr 06, 2015 3:40 pm Post subject: Air Leak Advice

No question that filling the emergency bottle with something like dry water pumped nitrogen would be better than filling it from the engine compressor Jan.



But consider this:   On your 50, empty the emergency bottle.  Easy to do, just loosen the fitting on the check valve on the firewall and let it bleed to zero.



Now connect to the external fill connection, and using dry water pumped nitrogen, fill it back up to 50 Atmos.  Unless your system leaks, that nitrogen will stay in there for a LONG time.    If you want, empty it every year and fill it again to make sure.   So you have now accomplished the same end that the 52 guys have right now, but more importantly.. if you ever have to blow the gear down with the emergency bottle AND IT DOES NOT WORK, you can fly around for awhile, let both bottle fill back up and try it again.



Personally, I like that, a LOT. 



Mark



________________________________

From: owner-yak-list-server(at)matronics.com [owner-yak-list-server(at)matronics.com] on behalf of Jan Mevis [jan.mevis(at)informavia.be]

Sent: Monday, April 06, 2015 12:26 PM

To: yak-list(at)matronics.com

Subject: Re: Re: Air Leak Advice






One of the reasons could be that the emergency bottle on the 52 gets

filled with perfectly dry air, from an industrial bottle.

So less probability of oxidation etc.

The water separator on the 50 can't do better than that.

I had to replace the water separator on my 50 almost immediately when I

bought it 10 years ago.

It was supposed to be overhauled in 2000 in Shakthy.

But I'm sure that they kept the original water separator from the eighties.

I still have it, I can simply blow through it without any effort.



Only an educated guess,



Jan



On 06/04/15 17:09, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:



[quote]

<mark.bitterlich(at)navy.mil>



On the 50 it also is filled from the compressor.



Wouldn't be too hard to change.   I've always been curious why the

Russians decided to fill it (from the compressor) on the 50 and not on

the 52.



Mark

--

AcroGimp

Joined: 11 Jun 2013
Posts: 45
Location: San Diego, CA USA

Posted: Mon Apr 06, 2015 6:33 pm Post subject: Re: Air Leak Advice

Update - got the check valve out with a surprising lack of injury or other frustration, heated it up (thanks to Dennis for the hat-tip on that to avoid galling), and it came apart easily.  Looked like oil in there, along with what appeared to be carbon deposit, not surprising it decided to start hanging up.



Will get a rebuild kit on the way tomorrow and then on to troubleshoot the gear actuators.















'Gimp

_________________
Owner/Pilot N6209F 1987 Yak-52
COMM/ASEL/IFR/HP-Complex/TW

jan.mevis(at)informavia.b
Guest

Posted: Mon Apr 06, 2015 10:22 pm Post subject: Air Leak Advice

I like this too.

Once a year I put the plane on jacks and check the emergency system too

(not having it slam the gear all the way).

At that occasion, both bottles are inspected and I refill completely with

industrial-quality dry air.

I thought about doing this annual check and refill with nitrogen, though.

She starts with nitrogen too (done it several times).

Jan

On 07/04/15 01:33, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:

[quote]

<mark.bitterlich(at)navy.mil>

No question that filling the emergency bottle with something like dry

water pumped nitrogen would be better than filling it from the engine

compressor Jan.

But consider this:   On your 50, empty the emergency bottle.  Easy to do,

just loosen the fitting on the check valve on the firewall and let it

bleed to zero.

Now connect to the external fill connection, and using dry water pumped

nitrogen, fill it back up to 50 Atmos.  Unless your system leaks, that

nitrogen will stay in there for a LONG time.    If you want, empty it

every year and fill it again to make sure.   So you have now accomplished

the same end that the 52 guys have right now, but more importantly.. if

you ever have to blow the gear down with the emergency bottle AND IT DOES

NOT WORK, you can fly around for awhile, let both bottle fill back up and

try it again.

Personally, I like that, a LOT. 

Mark

________________________________

From: owner-yak-list-server(at)matronics.com

[owner-yak-list-server(at)matronics.com] on behalf of Jan Mevis

[jan.mevis(at)informavia.be]

Sent: Monday, April 06, 2015 12:26 PM

To: yak-list(at)matronics.com

Subject: Re: Re: Air Leak Advice

One of the reasons could be that the emergency bottle on the 52 gets

filled with perfectly dry air, from an industrial bottle.

So less probability of oxidation etc.

The water separator on the 50 can't do better than that.

I had to replace the water separator on my 50 almost immediately when I

bought it 10 years ago.

It was supposed to be overhauled in 2000 in Shakthy.

But I'm sure that they kept the original water separator from the

eighties.

I still have it, I can simply blow through it without any effort.

Only an educated guess,

Jan

On 06/04/15 17:09, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:

>

><mark.bitterlich(at)navy.mil>

>

>On the 50 it also is filled from the compressor.

>

>Wouldn't be too hard to change.   I've always been curious why the

>Russians decided to fill it (from the compressor) on the 50 and not on

>the 52.

>

>Mark

>--

jliltd

Joined: 26 Jun 2013
Posts: 20

Posted: Tue Apr 07, 2015 5:02 am Post subject: Air Leak Advice

Jan,

You are correct. They start fine on Nitrogen.   Or any other type of inert gas or straight air. I would use either Nitrogen or bottled "breathing air" as used by fire fighter's breathing apparatus.   Whichever is cheaper at your local welding supply shop.

I run into many who argue Nitrogen doesn't work for starting as it is inert and thereby non-combustible.   That statement only exposes their lack of understanding of the internal combustion engine piston cycle.  Starting gas is injected into each cylinder on it's power stroke when both valves are closed, not on it's intake stroke, and then starter gas is expelled through the exhaust valve on the exhaust stroke.  So start air doesn't get involved in the combustion process.   The intake stroke still sucks in the normal fuel/air mixture from the carburetor prior compression and ignition.   If, on the other hand, the start gas were injected on the intake stroke where would the fuel required for ignition come from?  Also with the intake valve open wouldn't the high pressure starting gas be blown backwards down into the intake and carburetor?  These are the questions to ask the non-Nitrogen starting camp.

Jim

-------- Original message --------

From: Jan Mevis <jan.mevis(at)informavia.be> 

Date: 04/07/2015  12:22 AM  (GMT-07:00) 

To: yak-list(at)matronics.com 

Subject: Re: Yak-List: Re: Air Leak Advice 

--> Yak-List message posted by: Jan Mevis <jan.mevis(at)informavia.be>

I like this too.

Once a year I put the plane on jacks and check the emergency system too

(not having it slam the gear all the way).

At that occasion, both bottles are inspected and I refill completely with

industrial-quality dry air.

I thought about doing this annual check and refill with nitrogen, though.

She starts with nitrogen too (done it several times).

Jan

On 07/04/15 01:33, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:

[quote]--> Yak-List message posted by: "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil>

No question that filling the emergency bottle with something like dry

water pumped nitrogen would be better than filling it from the engine

compressor Jan.

But consider this:   On your 50, empty the emergency bottle.  Easy to do,

just loosen the fitting on the check valve on the firewall and let it

bleed to zero.

Now connect to the external fill connection, and using dry water pumped

nitrogen, fill it back up to 50 Atmos.  Unless your system leaks, that

nitrogen will stay in there for a LONG time.    If you want, empty it

every year and fill it again to make sure.   So you have now accomplished

the same end that the 52 guys have right now, but more importantly.. if

you ever have to blow the gear down with the emergency bottle AND IT DOES

NOT WORK, you can fly around for awhile, let both bottle fill back up and

try it again.

Personally, I like that, a LOT. 

Mark

________________________________

From: owner-yak-list-server(at)matronics.com

[owner-yak-list-server(at)matronics.com] on behalf of Jan Mevis

[jan.mevis(at)informavia.be]

Sent: Monday, April 06, 2015 12:26 PM

To: yak-list(at)matronics.com

Subject: Re: Yak-List: Re: Air Leak Advice

--> Yak-List message posted by: Jan Mevis <jan.mevis(at)informavia.be>

One of the reasons could be that the emergency bottle on the 52 gets

filled with perfectly dry air, from an industrial bottle.

So less probability of oxidation etc.

The water separator on the 50 can't do better than that.

I had to replace the water separator on my 50 almost immediately when I

bought it 10 years ago.

It was supposed to be overhauled in 2000 in Shakthy.

But I'm sure that they kept the original water separator from the

eighties.

I still have it, I can simply blow through it without any effort.

Only an educated guess,

Jan

On 06/04/15 17:09, "Bitterlich, Mark G CIV NAVAIR, WD"

<mark.bitterlich(at)navy.mil> wrote:

>--> Yak-List message posted by: "Bitterlich, Mark G CIV NAVAIR, WD"

><mark.bitterlich(at)navy.mil>

>

>On the 50 it also is filled from the compressor.

>

>Wouldn't be too hard to change.   I've always been curious why the

>Russians decided to fill it (from the compressor) on the 50 and not on

>the 52.

>

>Mark

>--

mark.bitterlich(at)navy.m
Guest

Posted: Tue Apr 07, 2015 7:00 am Post subject: Air Leak Advice

Jim, concur on what you said, but there is somewhat more to consider, both pro and con.   



 While air is being injected into one cylinder on the power stroke, another cylinder with no air being injected at all, is on the intake, or compression cycle, using nothing but "regular air".  That fact supports your premise of why in theory the engine should start perfectly with nitrogen in the starting bottle.   



 The bad part is that the air distributor is not as straight forward as you might think.  Logic says that it simply injects air into each cylinder on the power stroke, in firing order (kinda like a cars distributor), but what most folks do not know is that it ALSO injects air into the lower cylinders when the exhaust valves are OPEN (bottom three).  Due to camshaft overlap there will still be some nitrogen in those cylinders when they go into their intake cycle.  The Russians designed the air distributor this way to help "blow out" any oil collected in the lower three, which as everyone knows is a fact of life with radials.   Their engineers were pretty darn savvy (at least I think so).    



The third variable is the actual timing adjustment of the air distributor.  If you talk to anyone that has messed with these jewels, they can be difficult to get set "perfectly".  It is not unusual for someone to get to the point where they say: "Heck, that's good enough".  Point being, it would not surprise me if more than a few of our aircraft have this device slightly out of time.  Put all this together, and the end result is that the engine can be harder to start when you have pure nitrogen in the starting bottle, but it always WILL start if you "set it up" correctly with priming and pull through.   



So my 2 cents is that EVERYONE is correct regarding this topic!   



Mark

  



--

markdavis(at)wbsnet.org
Guest

Posted: Tue Apr 07, 2015 7:30 am Post subject: Air Leak Advice

The cylinders don't scavenge 100% on the exhaust stroke also contributes to a overly sweet blend of nitrogen.  I've had hard start issues with mine in the past if I've charged a depleted system with 100% nitrogen.  If it doesn't start on the first attempt, pull it through to recharge the cylinders and intake with pure air.  I've also found that opening the throttle just a bit more than normal also helps pull in more fresh air for starting.



Mark Davis

N44YK

--

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