Dr.Jeff
True Classic
In the "what did you do today" thread @Dan Sarandrea (Phila) said the following about burping the air out of his radiator:
"I am going to have to come up with a better venting/draining arrangement for burping as I HATE that burping results in a mess up in the radiator compartment and drips where it wants to drip, which is rarely in the drain pan!"
"I follow Jay Leno's burp technique that he uses on his Miura, do it while the cooling system is up to full temp and while the engine is running. That way the system's own internal pressure helps to expel the air. If you burp while the system is cold and not running, under certain circumstances I think opening the burp plug could let air in."
I don't intend for this to be the old debate about the X's cooling system design faults, or even question why a closed system should require repeated bleeding. But I'd like to throw around some ideas for better burping, without the mess Dan describes.
On one of my X's the original rad bleed bolt had been replaced by a prior owner with a simple plug. When I went to look for a suitable replacement bleeder valve I discovered that BMW radiators use the same size thread/diameter bleeder. Theirs is a different design; brass with a center hole for the air path and a slot for a screwdriver rather than the hex socket head. Looks like this:
I know from experience that it is easy to use and doesn't tend to get stuck or clogged. Plus they can be found easily for a couple of dollars online. So that's what I got to replace the missing one.
Not that this is any different in terms of what Dan is talking about. It will still allow a bit of fluid to leak when burping the system, running down the rad and spreading a mess everywhere. But in the process of searching for a replacement I found the bleeder's thread size/pitch [M10 (1.0) if I recall correctly - I can verify that]. So after reading Dan's comment today I got thinking how to improve the burping process and eliminate the mess. How about replacing the bleeder valve with a M10 (1.0) fitting with a hose barb, run a hose from it to the bottom of the rad, and add a common valve there. Then to bleed it you work from below instead of above, and any fluid will drain directly into your catch pan. Or if you prefer to not work from below, then install a valve with a hose barb directly into the rad's opening and then route the drain hose to the bottom. For that matter you could route the hose and valve to any convenient location to make reaching it easier - so long as your air path allows the air to escape before the fluid does. There is ample room above the X's bleed valve location to allow any changes in fittings, etc. And if you want to get fancy with either approach you could install corresponding fittings to attach a hard line rather than a hose, everything else being the same.
This seems very easy to do and would prevent the mess when burping the rad. Thoughts?
"I am going to have to come up with a better venting/draining arrangement for burping as I HATE that burping results in a mess up in the radiator compartment and drips where it wants to drip, which is rarely in the drain pan!"
"I follow Jay Leno's burp technique that he uses on his Miura, do it while the cooling system is up to full temp and while the engine is running. That way the system's own internal pressure helps to expel the air. If you burp while the system is cold and not running, under certain circumstances I think opening the burp plug could let air in."
I don't intend for this to be the old debate about the X's cooling system design faults, or even question why a closed system should require repeated bleeding. But I'd like to throw around some ideas for better burping, without the mess Dan describes.
On one of my X's the original rad bleed bolt had been replaced by a prior owner with a simple plug. When I went to look for a suitable replacement bleeder valve I discovered that BMW radiators use the same size thread/diameter bleeder. Theirs is a different design; brass with a center hole for the air path and a slot for a screwdriver rather than the hex socket head. Looks like this:
I know from experience that it is easy to use and doesn't tend to get stuck or clogged. Plus they can be found easily for a couple of dollars online. So that's what I got to replace the missing one.
Not that this is any different in terms of what Dan is talking about. It will still allow a bit of fluid to leak when burping the system, running down the rad and spreading a mess everywhere. But in the process of searching for a replacement I found the bleeder's thread size/pitch [M10 (1.0) if I recall correctly - I can verify that]. So after reading Dan's comment today I got thinking how to improve the burping process and eliminate the mess. How about replacing the bleeder valve with a M10 (1.0) fitting with a hose barb, run a hose from it to the bottom of the rad, and add a common valve there. Then to bleed it you work from below instead of above, and any fluid will drain directly into your catch pan. Or if you prefer to not work from below, then install a valve with a hose barb directly into the rad's opening and then route the drain hose to the bottom. For that matter you could route the hose and valve to any convenient location to make reaching it easier - so long as your air path allows the air to escape before the fluid does. There is ample room above the X's bleed valve location to allow any changes in fittings, etc. And if you want to get fancy with either approach you could install corresponding fittings to attach a hard line rather than a hose, everything else being the same.
This seems very easy to do and would prevent the mess when burping the rad. Thoughts?