Now that the oil sender switch is fixed, on to my next problem...

Today, the truck started to overheat and upon pulling over, I noticed steam coming from the passenger side of the radiator. The coolant reservoir was empty so I added a 50/50 mix and then it got home fine. After I shut it down, I popped the hood and the steam was not present but I could hear a hissing sound from the radiator. No coolant on the ground or steam present.

I am assuming that I am looking at a replacing a radiator now. If that is the case, I will do the hoses and thermostat as the same time. Anything else I should check first? How difficult of a time am I in for?

1997 F150xlt, supercab, 4.6L, 4x4, factory trans cooler, factory oil cooler
Thanks!

 

hissing when shut down is not uncommon. you are right, the coolant went somewhere. you need to see if the cap or hoses have a leak, or is it the radiator, or possibly the heater core. also check the dip stick to see if you have a head gasket problem and water getting into the oil (level will rise). dont buy a radiator right yet.

 

It was probably the seal for the tank on the P. side, mine started to go a few years back. I noticed a slight leak, coolant smell and it would hiss. Assuming you still have the mechanical fan it won't be a fun job. The shroud and fan need to come off then you can pull the radiator. It is simply held in with a few screws at the top and the bottom just has pegs that sit in a hole. Getting the fan off should be the hardest part. It would be an excellent time to put in a set of Efans if money allows, a new radiator alone from NAPA is around $300 IIRC though.

 

I checked for obvious leaks and did not find any. The pad I laid down under the radiator did not show any liquid during my tests tonight. I filled the coolant reservoir to the top of the cold fill range at the start. Here is what I have found.
Engine cold:

• No coolant in the engine oil
• No coolant in the transmission oil
• No oil in the coolant reservoir (checked before I filled it up)
• Hoses are soft but not cracked or bulging

Started the truck and let it warm up (idled for 10 minutes):

• temp gauge never went above halfway between L & H
• no leaks apparent
• ran with heater on for several minutes and no leaks inside the cab

Shut it down:

• Coolant reservoir level did not change
• Still no drips anywhere
• distinct hissing (like sizzling water) from the top left side of the radiator

Short of pressure testing the radiator, which I think would require it's removal, does anyone have any ideas? It is starting to look like galaxie641's suggestion on the seal may be correct.

 

either thermostat stuck and overheater and blow off the coolant, or the radiator cap was loose and blew out----- if you dont find a tank leaking.

 

I will try to drive it around a bit and see if I cant get the pressure up and find the leak. I guess would expect the coolant to drop continuously if there is a leak.

If I have to go through the hassle of pulling the old one, there is a new one going in.

Thanks!

 

I got the cooling system up to pressure and moved the fan shroud out of the way. I sprayed the radiator down with soapy water and the found the leak from the bubbles. it is the radiator. I suspect it has been leaking for some time and I just did not check the coolant closely enough.

Next step, new radiator. Does anyone know where I could purchase a copper/brass replacement instead of the aluminum/plastic OEM one? If it has 3 or 4 cores instead of the 2 I have, even better. I am not ruling out replacing the stock fan with a set of electric fans as recommended by galaxie641 either.

If it is all torn apart, what else should I replace as a preventative measure? Hoses, thermostat, and installing a T into the ECT port for a gauge is on my list already. Should a water pump be needed at 138,000 miles?

 

Probably. Someone told me when I was asking about the squealing in mine that the water pump is usually among the first things in an engine to go out, so you probably wouldn't go amiss by replacing it... Or at least taking it out and having it checked for proper function. I think AutoZone does the test for free or a minimal charge. shrug.

 

I have it all gutted and the new radiator comes in tomorrow. I know now that I do not want to tear this apart ever again.
So this being my last chance to replace stuff (by choice): I replaced the thermostat and o-ring. I will get the pump tested if anyone around here does it, (so far none of the shops I called do it). Replaced the ECT and plumbed in a T fitting for the future temp gauge.

The serpentine belt has a few cracks in it. Most people seem to prefer Gates over OEM or Gatorback? Any suggestions

Do I understand correctly that if I can get either of the block coolant plug drains out, I should. Otherwise it is more trouble than it is worth?

Should I mess with trying to clean out all the bugs and straighten the fins on the A/C coil in front of the radiator?

Thanks!

 

Help! Anyone have issues getting those transmission line hooked up? They were tight coming out and will go into the new radiator at all. I verified the threads were the same and even moved the fitting from the old rad to the new on and managed to get one line in. Should they be this hard to fit? Any suggestions welcome!

 

My guess would be yes. Otherwise, the pressure in the lines would probably blow the lines right off the radiator.

 

They can be hard to line up properly but with a little wiggling they should start. I know my new radiator had 2 different sets of inserts and I think I may have still had to use my stock ones. I would not tighten the top of the radiator until the lines are at least threaded some, that way you can still move the rad. around. IIRC the bottom line gave me a good 5-10 minutes worth of cussing before I got it lined up just right.

Probably too late but I'd replace everything you can. Belt, upper and lower hose, T-stat, check the water pump for any play. I'd also do the tranny fluid since the lines are unhooked, it is very easy to use the tranny pump to evacuate the old fluid through the cooler lines.

 

Thanks for the replies. I am taking a break as my fingers are sore from trying to line up the bottom one for the last hour. Changed the belt and all the hoses, and thermosat. Water pump seems fine so I left it alone.

Even the smooth part before the threads on the flare fitting wont go in. I guess I will keep trying. Thanks.