Happy Saturday all. I am hoping you guys can help me solve a mystery coolant leak issue. 30 model A, 51 flatty, Griffin 3" rad (2012 vintage very low milage) 4lb cap This fall I noticed that I had some spray on the driver side fender. It spread from the area around the lower left hose and petcock area and spreads back and up the fender... some spots on the edge of the firewall It only seems to leak when I am driving as there are no puddles on the garage floor,no matter how long it sits. (Yes there is still coolant in it) My first thought was maybe the lower hose was leaking when the pressure built up so I tightened the clamp, wiped everything down and took it for a ride... same problem. I thought maybe the left pump was weeping but there is no staining on the pump and how would the coolant get so far forward of the pump but only be down low... There is no staining or evidence of "standing" coolant anywhere on the back side of the rad (i.e. the top of the lower tank or fins) so I was thinking it may be an issue around the lower mount bracket or hose. Like a stress crack or something. Today I pulled the rad and I can not find any evidence of a leak anywhere... I pulled the petcock (it seemed to be tight enough that it wouldnt have leaked) and cleaned it up and checked it over and it seems to be ok... the flange and seat looked good so I put some new teflon tape on it and reinstalled it... I am at a loss as to what could be causing it to leak when driving but not leak while sitting, and I hate to put it all back together just to go through the dick dance of getting it apart again... Anyone have any thoughts on what could be causing this or have had this same issue in the past? Thanks Chappy
When you say spray,,,,you are sure it is coolant ,,right ? Can you put some dye in it,,,and check it with a light ? Sounds like a water pump seal,,,,just guessing. Tommy
Thanks guys.. Yes. Definitely coolant... green when I clean it off the fender... Would a water pump seal blow coolant forward past the pulley to the bottom corner of the radiator? And not leave any evidence on the front if the pump? Really hoping it's not a pump leak....lol Chappy
Since you already have the rad off, you should pressure check it. Sent from my SM-T350 using The H.A.M.B. mobile app
Sorry,,,,I just reread your post. I thought you meant left lower hose and petcock on block. No,,,,,,I don’t believe it would blow to the front,,,,,must be the rad leaking some. Sorry for the misunderstanding. Tommy
I’ve seen it where a rad will get a teeny tiny leak in the core, and leak slightly once coolant is flowing but seal up once the system get hot and the metal expands. The rads out! Take it to a rad shop and have them leak test it in there tank. for what it’s worth and if they find a leak to fix it, your probably all in well under 200 bucks, if not closer to 100. It’s out now so might as well confirm it’s all good.
Pressure test the radiator in some water. A tub or something and look for the bubbles. Block off the upper and lower ports. Pump it up a little higher than cap pressure and see what happens. Sent from my SM-G960U using The H.A.M.B. mobile app
Well. Looks like I have a small crack along the weld on the lower mount bracket... it would only leak when the car was running I am guessing it was the vibration flexing the crack open. I will try to get it welded up this weekend and then revisit the mounting... it was sitting on springs so I am not sure how this happened... Thanks for all the advice Chappy
Easy fix. A good problem. The weld looks to be alittle cold and missed hitting the seam. Poor fusion.
Next time before you pull everything apart visually looking for a leak, use a pressure tester connected to the radiator. Pump the tester up to cap pressure and start looking for leaks. Saves a lot of time and frustration. Sent from my iPhone using The H.A.M.B. mobile app
Yep. Those welds may look pretty but most of them are setting on top of the surface instead of blending into the material. I bet the welder used twice or three times as much weld as necessary. I never understood why people think stack dimes look good setting onto the top of metal. I bet he was trying to compensate for a poor fit. Now these are good welds. Good fusion. https://i.pinimg.com/originals/54/9c/a5/549ca5da33509d3c6b2fcdb661ce27c0.jpg
I have a question, just a passing thought. How are you mounting the radiator to the frame? I have seen it bolted down and this has caused failures like yours. I use a rubber pad between the radiator and frame along with a spring loaded fastener that allows the radiator to float. I’ll look for a picture. Cliff Ramsdell
Thanks for the input guys. The mounting is as follows (working from the bottom up Frame Rubber pad Radiator tab Nylon washer Spring SS Washer Castle nut Is there a different way to mount? I have seen some model T's with a spring on each side of the frame... Thanks again Chappy
Sounds like you have mounted it correctly for an early ford. I don’t know the recommendations for those, if at all different. I just used a rubber piece between chassis and radiator, but haven’t used it much so don’t know how long it will last
You are a good aluminum TIGer. Have you thought about a bit more to the mount, adding a strap upward to bridge the joint on the side?