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Author	Comments
marc dahncke Posted: Dec 28, 2007 10:41 AM	B side restriction Having consistent b side restriction. Y strainer is clear. Am able to spray by opening b manifold fully and a manifold only slightly. Would restriction most likely be in whip? If it's not there, what is the easiest, cleanest way to check rest of hose? thanks Marc Energy Wise Foam Insulation
Tim O'Keefe Posted: Dec 28, 2007 06:38 PM	B restrictions are rare. Can you recirculate without any problem? If not then your restriction would be in your supply. Did you drop anything in your B drums? What proportioner do you have? Did you check your gun filter? Do you spray open or closed cell? I would not recommend continuing to spray without fixing the problem first. Spraying off ratio even a little "B" rich can be catastrophic. Tim Granite State Spray Foam Co.
marc dahncke Posted: Dec 29, 2007 09:10 AM	Tim, Recirculation is fine. All screens are clear. I feel that there is "gunk" lining the b hose restricting flow under pressure. Hose guage reads full pressure. When b side is opened and triggered, only get a strong stream of material, no spray. What's the best solution? Is there a way to clean the hose or is replacement the only solution? Running E30 machine, nothing dropped in drum. Gun is clean. Spraying oc and cc foam (is it possible for cross contamination when switching foams?)
Gary Galloway Posted: Dec 29, 2007 01:50 PM	Have you tried a new mixing chamber in the gun ??? Had this happen a couple of months ago with a rented rig and discovered the mixing chamber was bad.
Lane Hogstad Posted: Dec 29, 2007 07:00 PM	How cold is your b side drum?
marc dahncke Posted: Dec 30, 2007 08:19 PM	Will try changing mix chamber tomorrow. Drum heat after recirc up to about 80 Thanks for all the input. I have gleaned much knowledge from many of the posts on this site.
clint moore Posted: Dec 31, 2007 01:06 PM	It's possible the chamber is clogged.Do you notice which material is streaming our of your gun? what about the pressure gauges,what do they read before and while you pull the trigger? If you have cold material this will also cause this effect,during colder months try running your "B" side preheater about 15-20 degrees higher than "A" side.
Michael Flander Posted: Jan 03, 2008 11:49 AM	Hi MDank, sorry it took a while to get back to you, I missed this post the first time around. Okay lets start off with your problem here.. a B-Side retriction is rare, and it does not have anything to do with your feed pump system. If a feed pump was a problem, your system would most likely be cavitating which would cause severe and sharp drops in pressure, which is not your problem. B-Side restrictions are almost always in the gun, usually around the mix chamber. Even if you have drilled the gun out thoroughly, the restriction could still remain, so try this, and make sure you are wearing your safety glasses: Use a can of carb clean with the little red straw that comes with them and squirt directly into the front of the mix chamber. If carb cleaner comes out of both the side orifices evenly, your mix chamber is cleared. If not, continue drilling out the material until it does. Another very common spot for a b-side restriction to occur is in the 90 degree part of the fluid manifold at the end of the hose(the part that attaches to the gun). Take this apart and thoroughly clean it, If the problem is not in your gun, this area is usually the culprit. If you have not had this problem before, and nothing has changed(you are spraying the same materials, etc) do not start changing temperatures or pressure to compensate for it. This will most certainly cause you to begin spraying off ratio, and will only put a band-aid on the problem as it continues to get worse. Maxx is correct that cold material could cause the problem, but you stated the drums were pre-heated to 80 degree's, so this would not be an issue. If cold material is a possibility, simply recirculate it back to the tank through the heaters until the barrels are at temp, do not compensate for it by spreading the temps on the machine. This will change the viscosities of the material and could have adverse effects. If you are still having a problem, give me a shout, I would be happy to help! My .02 cents... Mike Flander - Endisys 763-428-5075

Author

Comments

marc dahncke

Posted: Dec 28, 2007 10:41 AM

B side restriction

Having consistent b side restriction. Y strainer is clear. Am able to spray by opening b manifold fully and a manifold only slightly. Would restriction most likely be in whip? If it's not there, what is the easiest, cleanest way to check rest of hose?

thanks
Marc
Energy Wise Foam Insulation

Tim O'Keefe

Posted: Dec 28, 2007 06:38 PM

B restrictions are rare. Can you recirculate without any problem? If not then your restriction would be in your supply. Did you drop anything in your B drums? What proportioner do you have? Did you check your gun filter? Do you spray open or closed cell? I would not recommend continuing to spray without fixing the problem first. Spraying off ratio even a little "B" rich can be catastrophic.

Tim
Granite State Spray Foam Co.

marc dahncke

Posted: Dec 29, 2007 09:10 AM

Tim,
Recirculation is fine. All screens are clear. I feel that there is "gunk" lining the b hose restricting flow under pressure. Hose guage reads full pressure. When b side is opened and triggered, only get a strong stream of material, no spray. What's the best solution? Is there a way to clean the hose or is replacement the only solution? Running E30 machine, nothing dropped in drum. Gun is clean. Spraying oc and cc foam (is it possible for cross contamination when switching foams?)

Gary Galloway

Posted: Dec 29, 2007 01:50 PM

Have you tried a new mixing chamber in the gun ??? Had this happen a couple of months ago with a rented rig and discovered the mixing chamber was bad.

Lane Hogstad

Posted: Dec 29, 2007 07:00 PM

How cold is your b side drum?

marc dahncke

Posted: Dec 30, 2007 08:19 PM

Will try changing mix chamber tomorrow.

Drum heat after recirc up to about 80

Thanks for all the input. I have gleaned much knowledge from many of the posts on this site.

clint moore

Posted: Dec 31, 2007 01:06 PM

It's possible the chamber is clogged.Do you notice which material is streaming our of your gun? what about the pressure gauges,what do they read before and while you pull the trigger? If you have cold material this will also cause this effect,during colder months try running your "B" side preheater about 15-20 degrees higher than "A" side.

Michael Flander

Posted: Jan 03, 2008 11:49 AM

Hi MDank, sorry it took a while to get back to you, I missed this post the first time around.

Okay lets start off with your problem here.. a B-Side retriction is rare, and it does not have anything to do with your feed pump system. If a feed pump was a problem, your system would most likely be cavitating which would cause severe and sharp drops in pressure, which is not your problem.

B-Side restrictions are almost always in the gun, usually around the mix chamber. Even if you have drilled the gun out thoroughly, the restriction could still remain, so try this, and make sure you are wearing your safety glasses:

Use a can of carb clean with the little red straw that comes with them and squirt directly into the front of the mix chamber. If carb cleaner comes out of both the side orifices evenly, your mix chamber is cleared. If not, continue drilling out the material until it does.

Another very common spot for a b-side restriction to occur is in the 90 degree part of the fluid manifold at the end of the hose(the part that attaches to the gun). Take this apart and thoroughly clean it, If the problem is not in your gun, this area is usually the culprit.

If you have not had this problem before, and nothing has changed(you are spraying the same materials, etc) do not start changing temperatures or pressure to compensate for it. This will most certainly cause you to begin spraying off ratio, and will only put a band-aid on the problem as it continues to get worse.

Maxx is correct that cold material could cause the problem, but you stated the drums were pre-heated to 80 degree's, so this would not be an issue. If cold material is a possibility, simply recirculate it back to the tank through the heaters until the barrels are at temp, do not compensate for it by spreading the temps on the machine. This will change the viscosities of the material and could have adverse effects.

If you are still having a problem, give me a shout, I would be happy to help!

My .02 cents...
Mike Flander - Endisys
763-428-5075

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