baucco

Hey there,I just bought a 94 F150 XLT 4x4 5.8 ltr. and the PO told me he was having an issue with having to replace the coolant often.He also said there was no heat,but I played with it a bit and it gets plenty warm now. I replaced the old crusty hard lower hose and flushed the system. No overheating,no leaks.Any ideas about where I should look now? Thanks in advance,Dan

BCMIF150

It's probably going though the head gasket if there are no visible leaks.

13Harleyfan

Normally if the head gasket is the problem it causes the water/coolant to boil out of the overflow. Since that wasn't mentioned I would get somebody to put a pressure tester on it to see if you can hear or see an external leak. Check the gasket on the radiator cap and if it's suspect, replace it.

'12 FX4

Check your oil. If it's looking milky it going there.

Check your exhaust for white smoke.

So,intake manifold gasket or head gasket.

dereku

Its easy enough and cheap enough to do top end gaskets in a few hours on the 351.

Just doing that would have to fix your issue no where else it could go.

And while you do all that you can re lap the valves and clean all the carbon off everything , intake and throttle body.

Prolly run like new!

wmasmith

iTrader: (1)

I'm with dereku, when I worked at the garage in college we had the contract for the PDA, Pueblo Depot Authority, and they ran almost exclusively fords. Any time we got something in like this we would check the oil then replace the head gaskets and the water pump. The pump can leak in such a way that it will evaporate before it starts to drip. Of course it depends on how fast you are loosing the coolant too though. When you pull the head if it's a gasket or cracked block it will be the cleanest cylinder bore you have ever seen. You can also try to do a leak-down test on the cylinders as well. If it runs rough I wouldn't bother with too much troubleshooting and just replace the head gaskets and water pump.

dereku

Yup old engines are simple, try telling someone with a 5.4 to just pop the heads it will fix it. Haha. Take advantage of your easy to fix engine and make it run like new!

baucco

Thanks for the input folks.I've already checked some of these,no coolant in the exhaust or oil. No excessive smoke,so It looks like I'll be digging a little deeper this weekend.