rottov Posted October 8, 2019 Report Share Posted October 8, 2019 Can anyone help me find the coolant drain plug in a flathead block???? I have a 1949 B1D pick up and I've not been able to find the plug. Thanks for your help. Quote Link to comment Share on other sites More sharing options...
Reg Evans Posted October 8, 2019 Report Share Posted October 8, 2019 (edited) The pet cock drain is on the distributer side of the block near the oil fill tube and distributer. Edited October 8, 2019 by Reg Evans Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted October 8, 2019 Report Share Posted October 8, 2019 Reg beat me to the reply button....but yes, where he says....you may not find a petcock as some PO may have put a plug there do to a leaking or damaged unit... Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted October 8, 2019 Report Share Posted October 8, 2019 Yup, like they said... Here’s a photo for your reference. Quote Link to comment Share on other sites More sharing options...
rottov Posted October 9, 2019 Author Report Share Posted October 9, 2019 Thanks for sending the picture and reply - it's easy to find when someone points it out!!!! Quote Link to comment Share on other sites More sharing options...
kencombs Posted October 9, 2019 Report Share Posted October 9, 2019 Merle's pic reminded me that there use to be a petcock with an extended tube. Not much 1/2 inch or so. Just enough to allow you to slip a piece of tubing on it. Negated the need for the cardboard chute in the pic. But, just came from the parts store and didn't see any. Anybody know of a source, preferably in brass as I hate how steel ones rust and become hard to move. Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted October 9, 2019 Report Share Posted October 9, 2019 (edited) I have determined that the next time I have to drain the coolant I will be putting one of those in. I suppose I should get one to have on hand when that day comes... Here’s one on Amazon Dorman 61106 HELP! Radiator Drain Cock https://www.amazon.com/dp/B000C5CBD2/ref=cm_sw_r_cp_tai_AfMNDbM2RFFF1 Well, it seems that the Dorman one has some pretty poor reviews that the wing tends to come loose from the stem after one use, making it useless. Napa also lists one... Weatherhead brand. https://www.napaonline.com/en/p/WH_6783?partTypeName=Brass+Fitting+Drain+and+Drain+Cock&keywordInput=drain+cock And O’Rielly also lists a Gates brand on their web site. It doesn’t appear that the stores stock the, but they can get the ordered in. Edited October 9, 2019 by Merle Coggins Quote Link to comment Share on other sites More sharing options...
Jerry Roberts Posted October 10, 2019 Report Share Posted October 10, 2019 That looks just like the brass nipple that I soldered onto the drain cock on my oil filter housing . It works well . Quote Link to comment Share on other sites More sharing options...
ggdad1951 Posted October 10, 2019 Report Share Posted October 10, 2019 you can also drain via the petcock on the bottom of the radiator.... Quote Link to comment Share on other sites More sharing options...
Fernando Mendes Posted October 10, 2019 Report Share Posted October 10, 2019 On 10/8/2019 at 8:58 PM, Merle Coggins said: Yup, like they said... Here’s a photo for your reference. Merle,I use a piece of tire tube to avoid the water throw in the filler oil tube. Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 I have an issue with my petcock on the block of my 251 flathead ( 48 Chrysler) . I want to open it because I'm changing the coolant and all I can get out of the rad drain is about 7 litres. When I open the block petcock, ( screw in) nothing comes out ?? I tried to get a soft flexible wire into the opening hoping it would bend once it bottomed out and clear any blockage, but no luck. So my next plan is to pull the drain petcock out. It's in there pretty tight. A 9/16 wrench fits it but not much room to get any pressure on the wrench. Best angle seems to be to tuck the wrench in behind the oil filler tube. Not sure what I'll discover once it's out, but if it gets destroyed, I want to have one ready to replace it. Is it just a standard size plug and pipe threads? The reason I ask that is NAPA auto parts (Canada) has 3 slightly different styles available but when I chose 48 Chrysler, it says won't fit my vehicle Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted October 12, 2019 Report Share Posted October 12, 2019 sounds like the typical block after years of service...am certain you will find a sediment plug behind the petcock..... Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 I'm wondering if it would be easier to get that plug out with the engine hot or cold? Since I can't get a box end wrench on to the plug without destroying the wings, if it's hot, the open end wrench might just slip off the brass and round the edges. Once I get it off, I suspect I should flush out the system. In the old days it was called back flushing and a "T" fitting was installed into the 3/4" hose going to the heater I think. But it's been 50 years since I did that so I don't remember precisely. I don't really want to put a back flush "T" into the system because it will spoil the authenticity or originality of what's under the hood. Any suggestions as to how to clean out the cooling system? Oh btw, it's not overheating and the thermostat seems to be operating just fine according to the gauge, but I wanted to change the fluid because it was weak and now that I know about the plug issue I want to make sure the cooling system is as good as I can get it. Quote Link to comment Share on other sites More sharing options...
JBNeal Posted October 12, 2019 Report Share Posted October 12, 2019 had one 230 that crud had built up to the top freeze plugs, fluid was dripping out of that drain for days before I kicked things up a notch by removing the distributor and oil fill tube for better access to that drain, worked on it carefully off and on by tightening then loosening it a fraction of a turn before it fully unscrewed a few days later...worked a tire coat hanger in there to clean out the crud in the coolant passages, could not believe how much congealed goo and a few small brown flakes oozed out...pulled the thermostat and ran a garden hose moderate flow to flush until water ran clear, let it sit for a week then flushed again to get what I missed the first time...took the drain to a local hardware store, they had a few styles to choose from...buttoned the whole thing up, drove it with straight water for a few days, which knocked some more crud loose when I purged it again...filled it back up with 50/50 coolant mix and ran it for several year, engine came up to operating temp faster with everything back to normal Quote Link to comment Share on other sites More sharing options...
Los_Control Posted October 12, 2019 Report Share Posted October 12, 2019 Should be standard pipe threads. My drain cock was the same way, I had the opportunity to pull the welsh plugs out and flush it that way. Now my petcock works and I never removed it. Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 4 minutes ago, JBNeal said: had one 230 that crud had built up to the top freeze plugs, fluid was dripping out of that drain for days before I kicked things up a notch by removing the distributor and oil fill tube for better access to that drain, worked on it carefully off and on by tightening then loosening it a fraction of a turn before it fully unscrewed a few days later...worked a tire coat hanger in there to clean out the crud in the coolant passages, could not believe how much congealed goo and a few small brown flakes oozed out...pulled the thermostat and ran a garden hose moderate flow to flush until water ran clear, let it sit for a week then flushed again to get what I missed the first time...took the drain to a local hardware store, they had a few styles to choose from...buttoned the whole thing up, drove it with straight water for a few days, which knocked some more crud loose when I purged it again...filled it back up with 50/50 coolant mix and ran it for several year, engine came up to operating temp faster with everything back to normal So it sounds like patience is the key. It also sounds like it's just a standard pipe thread so any of the petcocks available at NAPA should work I suppose. Knowing that allows me the luxury of bending the wings off of the petcock and using a socket wrench, slow and easy. I'm curious how you removed the oil filler tube? Did you seal it after reinstalling it with JB weld or something? Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 5 minutes ago, Los_Control said: Should be standard pipe threads. My drain cock was the same way, I had the opportunity to pull the welsh plugs out and flush it that way. Now my petcock works and I never removed it. I'd prefer not to disturb a frost plug, but perhaps a fine spray of water from the garden hose in the block opening once I get the plug out will be enough to clean out any sludge if I do it enough times. Quote Link to comment Share on other sites More sharing options...
JBNeal Posted October 12, 2019 Report Share Posted October 12, 2019 Fill tube had a bracket near the head and was pressed into its block bore...unbolted then carefully rocked until it wiggled loose...before reinstalling, I worked a little on the anvil horn to open the tube back up for a tighter fit in the block, slathered some #1 yellow grease on the tube end and rocked it back into place...next time around I'm just gonna put a small bead of black RTV near the tube shoulder and call it good Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 Potentially that petcock has been in there 71 years. I'm wonder if I should spray around the threads with Liquid Wrench several times for a few days, or if that would just be a waste of time. Quote Link to comment Share on other sites More sharing options...
JBNeal Posted October 12, 2019 Report Share Posted October 12, 2019 More than likely it is froze up from the inside, hence why I recommend tightening the drain to break any crud off of the threads without jamming the threads with said crud Quote Link to comment Share on other sites More sharing options...
Los_Control Posted October 12, 2019 Report Share Posted October 12, 2019 1 minute ago, harmony said: I'd prefer not to disturb a frost plug, but perhaps a fine spray of water from the garden hose in the block opening once I get the plug out will be enough to clean out any sludge if I do it enough times. I probably would not either ... usually this problem is accompanied with a engine running hotter then wanted. Your goal is to change the coolant. Would not want to create more work then needed. On the other hand, the soft plug above the starter is easy to get to, then the one behind the oil fill tube, with the tube removed ... a hose in the top one and flush it out the bottom, you would be surprised at how much will come out. And trying to get it all out of the little petcock drain hole may take days and still never get it. But if you have no issues, maybe flushing through the petcock will be all you need. Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 2 minutes ago, Los_Control said: I probably would not either ... usually this problem is accompanied with a engine running hotter then wanted. Your goal is to change the coolant. Would not want to create more work then needed. On the other hand, the soft plug above the starter is easy to get to, then the one behind the oil fill tube, with the tube removed ... a hose in the top one and flush it out the bottom, you would be surprised at how much will come out. And trying to get it all out of the little petcock drain hole may take days and still never get it. But if you have no issues, maybe flushing through the petcock will be all you need. I'll give that some thought, I'll try the simplest method first. Maybe while I'm getting the petcock I should pick up a frost plug. Once again it's been 40 - 50 years since I replaced a frost plug. When I'm putting the new one in, do I just clean up the block with some fine sandpaper and tap it in with a rubber dead blow hammer? Quote Link to comment Share on other sites More sharing options...
Los_Control Posted October 12, 2019 Report Share Posted October 12, 2019 24 minutes ago, harmony said: When I'm putting the new one in, do I just clean up the block with some fine sandpaper and tap it in with a rubber dead blow hammer? I am still learning that part. I cleaned mine up, then installed new dry using a round pipe to tap tem in, and they did weep a little bit but seem to have stopped now. Others like to use a bit of sealant, then they drive them in hard enough to put a dimple in the middle, this spreads the plug out for a tighter fit. I think I need to go back and add the dimple so I feel better. To remove them, is real simple to use a self tapping screw in the plug, then use a pry bar or hammer to pull them out. They are 1 5/8" diameter. And they are fairly thin, and proper name is a welsh plug. A soft plug has a deeper recess and do not fit these engines. My local carquest store had both kind in stock, not a hard item to find. Quote Link to comment Share on other sites More sharing options...
harmony Posted October 12, 2019 Report Share Posted October 12, 2019 3 minutes ago, Los_Control said: I am still learning that part. I cleaned mine up, then installed new dry using a round pipe to tap tem in, and they did weep a little bit but seem to have stopped now. Others like to use a bit of sealant, then they drive them in hard enough to put a dimple in the middle, this spreads the plug out for a tighter fit. I think I need to go back and add the dimple so I feel better. To remove them, is real simple to use a self tapping screw in the plug, then use a pry bar or hammer to pull them out. They are 1 5/8" diameter. And they are fairly thin, and proper name is a welsh plug. A soft plug has a deeper recess and do not fit these engines. My local carquest store had both kind in stock, not a hard item to find. good to know about the size of them. I've always just been around guys that called them frost plugs. So you're saying a "soft" plug is deeper than a "welsh" plug? How deep is the welsh plug that you used? Quote Link to comment Share on other sites More sharing options...
Los_Control Posted October 12, 2019 Report Share Posted October 12, 2019 here is what mine looked like, and I bought brass replacements Here is a example of the deeper one I spoke of Quote Link to comment Share on other sites More sharing options...
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