So, after doing a head job, I put everything back together and now I have this strange noise (in water pump) after the engine gets up to operating temp. Its like the water is boiling inside or I have air in the cooling system. I installed a new water pump and tried several times to burp the system of air, but not working. Changed from a 195 df to 180 df thermostat. Been parking it on an incline and leaving the cap off the radiator to let it burp. When I rev it up it sucks the coolant down so I know the pump is actually working. I installed an overflow tank. heater is on high and blowing hot air in cab. Never overtemps! Even went back and checked the head bolts and retorqued them. Any ideas? Thanks guys!

 

Usually don't have air issues in these engines / trucks, but just in case lift the front of the truck with a jack, or on a hill and run with the rad cap off to burp all the air out. I would try that first.

 

Already tried multiple times. Even after truck is shut off, the ticking continues for a few minutes till it cools down.

 

umm, you havent got the head gaskets around the wrong way?
hope not. That may be airlocking the head cooling passages.
Is the thermostat correct.
may sound like a stupid question, but I've heard a lot of mistakes from parts stores giving out windsor stats and they are not right.

 

I made sure the head gaskets were in the right direction- stamped "front" on Felpro gaskets. I checked the t-stat also. Made sure it was the correct one. Did a lot of research on that too. Thanks for the reminder. I'm going to pull the water pump and replace with another new one and see if that helps. If the gasket was leaking, wouldn't I see some indication in the exhaust at the tailpipe? The noise is localized at the water pump too. ????? Puzzled! ????

 

Ok-cool. Sounds like it is becoming even more of a PITA! Must say though, if it isn't overheating or using water, is there actually a problem?

 

No, doesn't overheat at all. The noise just makes me a little nervous. Concerned I might be starving the engine some cooling in the block. Don't want to cook something. Its really noisy when you come up to a stop or idle. You can hear it from 10' away.

 

Are you certain you've got the thermostat pointing the right direction?

 

IIRR...the thermostats in the 351 & 400 engines had a unique design...the standard would restrict flow.

 

You are right bearT. But that is why That's why I asked if he had the right Tstat. 351 has a pressed thingie, while the 400 has it cast-or is it the other way around? Just make sure it isn't a windsor one

 

Yeah, very certain I have the T-stat in the right way and the proper one. I read up on the peculiarities of the ford 400 and made sure I got the right one. Some members even suggested drilling one or two 1/8" holes in the stat to allow the air to escape as its warming up. Tried that also. Still the same.

 

Right-not much left then-have you tried running around without the rad cap on? Now you have said you already replaced the water pump-something rings a bell about being in reverse if you have the wrong one-someone else may be able to confirm this but A-can a windsor one be fitted, and B-does it spin the right way. I don't know but there is something needleing the memory banks about that one.

 

Agreed.
Is the noise consistent...as a lifter tick type noise?
But with the replacement of the water pump, I can't help but think of the pump's bolt placements. Various dimensions.....in particular, the one by the fuel pump arm. Probably way off here...just a thought.

 

water pump check. check the clearance between plate to impellar. About .005 max. clearance should help prevent bypass within pump. On your heater hoses does one have a restricted port to heater core? checking impellar clearance can be checked with a piece of glass laid on top and use a feeler gage for reference. next the gasket thickness is figured into clearance. but if the pump has to much impellar clearance your just creating more problems. Reason I'm going this way is because of quality control these days is not so good! Assume nothing is my policy and still probably not enough! good luck!

 

Keep us posted on your progress, or lack there of. I'm always following strange issues because you never know when it could happen to you next.
Good Luck!