Missing Bleed Screw on T-Stat
Hi all,
I recently tried to change my coolant, and noticed that the bleed valve described in the owner's manual isn't there. There's a smooth hole in the top cover of the thermostat valve, with large diameter going to smaller diameter (presumably for the threads of the screw that's supposed to be there - no threads cut, though) and then a plug at the bottom. I took the cover off, and the plug looks like it is part of the cover casting, not simply a broken-off bleed screw.
Is this normal or maybe some sort of revision? If there's no bleeder there, where the heck do I bleed the cooling circuit? I'm tempted to just drill out the plug, tap the hole, and put a bolt in, but I figured I'd consult the experts before taking drastic action.
Thanks a lot guys! Appreciate the help...
-Johan
I recently tried to change my coolant, and noticed that the bleed valve described in the owner's manual isn't there. There's a smooth hole in the top cover of the thermostat valve, with large diameter going to smaller diameter (presumably for the threads of the screw that's supposed to be there - no threads cut, though) and then a plug at the bottom. I took the cover off, and the plug looks like it is part of the cover casting, not simply a broken-off bleed screw.
Is this normal or maybe some sort of revision? If there's no bleeder there, where the heck do I bleed the cooling circuit? I'm tempted to just drill out the plug, tap the hole, and put a bolt in, but I figured I'd consult the experts before taking drastic action.
Thanks a lot guys! Appreciate the help...
-Johan
- Maurizio
- Verde
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Mats take a look at a V6 for a change
I recently bought a thermostat for my QV. And at the alfa parts store they had a 164 thermost laying around. This didn't have the bleed screw and was a bit cheaper.
I ordered one with a bleed screw, to be sure.
My guess is that the water routing is different on the fwd V6's but didn't check this.
I recently bought a thermostat for my QV. And at the alfa parts store they had a 164 thermost laying around. This didn't have the bleed screw and was a bit cheaper.
I ordered one with a bleed screw, to be sure.
My guess is that the water routing is different on the fwd V6's but didn't check this.
Banned.. ? Daily donky.. ==> BMW 325d
E36M3 (3.0) Ringtool ==> definitely BANNED!
AR 75 TS Ringtool '90, AR Spider 2000 veloce '79
E36M3 (3.0) Ringtool ==> definitely BANNED!
AR 75 TS Ringtool '90, AR Spider 2000 veloce '79
I suspect some aftermarket thermostats did not have the bleed screw. Personally, I wouldn't be too concerned. On the Milano/75 V6 you can "upset" the coolant by pressing the upper radiator hose forcefully with your hand. This tends to move things around enough to get large air pockets to rise to the overflow bottle.
Jes
Jes
87 Milano Verde - daily driver - Juliet
87 Milano 3.0 Motronic - budget race car - Roxanne
87 Milano 3.7 24v - race car
(Repeat or do as I say at your own risk - be critical)
87 Milano 3.0 Motronic - budget race car - Roxanne
87 Milano 3.7 24v - race car
(Repeat or do as I say at your own risk - be critical)
Thanks AR4me.
I talked to my mechanic and he thinks that if you can get all of the capactity of fluid in there then there should be no problems.
I put 8 litres in there, he thinks that you would only be able to put about 4 litres in if there was serious air in the system.
I did squeeze all of the hoses and it did clear some air.
Thanks all, I hope this helps some people.
I talked to my mechanic and he thinks that if you can get all of the capactity of fluid in there then there should be no problems.
I put 8 litres in there, he thinks that you would only be able to put about 4 litres in if there was serious air in the system.
I did squeeze all of the hoses and it did clear some air.
Thanks all, I hope this helps some people.
Johank:
New to me....looks like it's not tapped (obviously...otherwise major leak)
tap it and put in a bleed screw...will help when filling system
I'm in Plymouth...let me know when you are in the area!!
if you need parts there is a guy with lots of new and used on Ann Arbor trail just east of garden city.....
New to me....looks like it's not tapped (obviously...otherwise major leak)
tap it and put in a bleed screw...will help when filling system
I'm in Plymouth...let me know when you are in the area!!
if you need parts there is a guy with lots of new and used on Ann Arbor trail just east of garden city.....
I've recently had a bit of "fun" with the cooling system. I'd stay away from the drill on this one as its not really necessary to bleed it that way. if you top up the resivoir bottle then heat cycle the engine (bring it to operating temp then let it cool down) several times it will bleed itself. just check the coolant level each night for a week after you get home from work and keep the resivoir topped up. You will see some usage initially and then you won't be adding to the system anymore. at that point you're finished. realize also that as the coolant expands when heated you may have some coolant go out the overflow. What you will see is that once bled the resivoir will always have coolant in it.
HTH,
Scott
HTH,
Scott
For anyone still reading this (better late than never):
I ended up initially doing what Scott said last year and it probably was o.k., but I didn't like that the car was dumping coolant every time the engine was turned off after being hot. It did seem like it was getting less each time, but I just was not happy with it.
So I got a new bleed screw from IAP ($13! but I guess it's fancy enough to merit that price) this summer and drilled and tapped the cover. That seems to have done the trick.
X-rad - actually moved out of AA, but I'll let you know if I'm ever back in town. Would love to check out your Alfa!
Thanks again for the help...
I ended up initially doing what Scott said last year and it probably was o.k., but I didn't like that the car was dumping coolant every time the engine was turned off after being hot. It did seem like it was getting less each time, but I just was not happy with it.
So I got a new bleed screw from IAP ($13! but I guess it's fancy enough to merit that price) this summer and drilled and tapped the cover. That seems to have done the trick.
X-rad - actually moved out of AA, but I'll let you know if I'm ever back in town. Would love to check out your Alfa!
Thanks again for the help...