Hi all
Can't tell where its coming from. no drips, very little loss, but I can smell it every time I get out of the truck. I can see wet under the t-stat cover but can't tell where its coming from. Any Ideas from the group?

 

Check the hoses. There may be a hairline crack that hasn't burst yet. There is a lot of pressure in the system and that is all that it takes to leak out. When was the last time you changed the stat? If the stat needs changing, replace the gasket,.....which could also be the problem. Finally, check the radiator itself, it may have a crack as well. There could be other areas, but these are the easiest and most obvious. Someone will be along to give you a better diagnosis.

 

Thanks for the tips. Rad was new 2 yrs ago and hoses just last year. May be the t-stat gasket, haven't changed that yet.

 

you explained my problem perfectly i haven't really looked into it yet because of other projects and it is much easier to just add water once a month. I am pretty sure that last time i changed my thermostat and scraped the old gasket off of the housing i put i scratch in the housing that slowly drips water. like i said i havent looked into it so i dont know for sure that is just my theory it started leaking when i replaced it about 6 months ago so i have a good gasket. let me know what you find out

by the way i also have the 5.0

 

Gents,

I am currently having the same problem with my 91 F150. It has a 5.0 in it as well. Were either if you able to discover the source of the leak?

Shawn

 

Make sure the thermostat did not slip down out of the groove and not have the water neck seat correctly. Happens alot. I usually put a little silicone on the neck to keep the thermo in the groove. Also the gaskets do go bad after a while. I just replaced mine. It was factory.

 

Hi Shawn, my 91 5.8L had a simular leak. turns out to be a small tear in the heater hose going to the waterpump. fixed that and now have a bigger leak coming from the lower intake manifold gasket.

 

Had the same problem in my '96 5.0. Always smelled a faint odor of antifreeze and could not keep the reservoir filled. But I never saw signs of leakage except from around the thermostat. Turned out the thermo was fine but there was a leak in the timing belt cover. Apparently there is a collant passage within that. Got a new gasket on the cover and alls well now. Cost about $300 though but that included a new oil pan gasket also. Good Luck

 

Dirt, Mike, Steel,

Thanks for your advice. I have checked the thermostat and all was well. Since them I have investigated further and have found two possibilities. Both have been mentioned. Currently I am replacing both the intake and timing chain cover gasket. Hopefully this will solve the issue.

Thanks again

Shawn

 

Hello all.

I about fell over when I read this thread. I have a 1990 with 5.0 and have the same experience. Faint coolant odor, reservoir empty, coolant around the thermostat housing. I bought the truck in March and have used about a gallon of antifreeze in 5,000 miles.
I couldn't get the housing bolts any tighter, so I decided to live with the problem (and make sure my AAA towing was paid!).

Thanks for the heads up steely34, and the rest of you, too.