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longhorn
10-29-2011, 06:56 PM
I bought a 1/2 ton F-150 4x4 with a 300 six in it.
Seller said they did the headgasket and you can tell its been apart.

The oil is crystal clean and the coolant is nice and green.
No contaminants anywhere.

Its got tons of white smoke coming out the tailpipe.

Suppose they put the head gasket in wrong?

Any ideas?

BuckNaked
10-29-2011, 07:01 PM
sounds like it

geezer
10-29-2011, 07:17 PM
Sounds like coolant in the exhaust, probably caused by a faulty head gasket installation or possibly, there could be a crack in the head around an exhaust port where it meets a coolant passage. If there is condensed water coming out of the tailpipe and rust inside the pipe you have found your culprit. It could be that the head bolts weren't torqued properly or re-torqued after a day or two to ensure the proper torque rating was achieved. Possibly, the person who replaced the head gasket used the old head bolts which will have stretched threads and not give you a proper seal which in turn would allow the coolant to flow past the head gasket. I have also seen head gaskets installed upside down which will cause leakages including coolant and compression losses. Try this... if you have access to compressed air with a fitting to fit into a spark plug hole, shoot some compressed air into each cylinder and remove the rad cap and watch for air bubbles escaping out of the rad. That will tell you what is happening and from which cylinder(s). Another thing you can do but would necessitate buying a tool is purchase a leak-down tester that will measure and locate head gasket problems along with other engine failures. One other thing that could have happened is the cylinder head itself is warped and was just rebolted onto the block that way. You would not get a proper seal then, resulting in your symptom of white smoke, which is actually steam mixed with antifreeze. I hope this has helped you.

geezer
10-29-2011, 07:31 PM
I have owned 3 such 300 straight 6 Ford engines and I think they are one the best truck gas engines ever made by any maker. 2 of them were in F-150 4x4's and those trucks just crawled up hills without even using the throttle pedal in 4-low. I have also worked on and rebuilt several of these engines and they are very rugged and reliable engines and cheap to run. Just like any engine though, if not maintained properly will break down but they can put up with a lot of abuse but aren't high revving engines, just good old fashioned bottom end torque. I'm a big fan of the 300-6, especially with a standard transmission behind it. How is the rest of your trucks' condition? Any frame rot? How are the body mounts?

longhorn
10-29-2011, 07:46 PM
Geezer the head was tested and done by a repubale head place, so im leaning towards the guy not installing it right..

Ill try your air in the plug holes.....

geezer
10-29-2011, 07:54 PM
Good stuff, let us know how you make out.

4skin
10-30-2011, 01:04 PM
how long has it been ran since the head gasket was done
it can take quite some time for the exhaust system to burn off
the coolant that it filled with
seen it take several days of driving

longhorn
10-30-2011, 04:05 PM
how long has it been ran since the head gasket was done
it can take quite some time for the exhaust system to burn off
the coolant that it filled with
seen it take several days of driving

I was wondering the same thing it hasnt gon 20 kms since the job was done.

Its a real heavy smoke screen however like more than just a bit?

Toyquad
10-30-2011, 04:16 PM
run it and see what happens. if the coolant isnt mixing with the oil and it doesnt overheat, no real damage will be done by running it.

4skin
10-30-2011, 04:21 PM
id try running it and just keep a close eye on coolant level
and for oil contamination
or if you have a rad pressure tester check with that
if i remember on the 300 you cant put head gasket wrong
have seen the coolant cross over in the efi throtle body leak
into the intake

longhorn
10-30-2011, 05:20 PM
id try running it and just keep a close eye on coolant level
and for oil contamination
or if you have a rad pressure tester check with that
if i remember on the 300 you cant put head gasket wrong
have seen the coolant cross over in the efi throtle body leak
into the intake

Can you see that crossover?
How would i test or look for that?

m j
10-30-2011, 05:31 PM
ford runs coolant to the EGR to cool it.
will be right at tyhe throttlebody on other engines, never looked too close at 300s
post a pic

4skin
10-30-2011, 11:26 PM
Can you see that crossover?
How would i test or look for that?
a radiator pressure test will show any leaks in the cooling system[cheers]

longhorn
11-11-2011, 05:37 PM
Ive been driving it.
It quit smoking and isnt getting hot or anything.

Oils clean and so is the coolant?
Suppose it was just old shit in it?

Ive never got that lucky before?

4skin
11-12-2011, 10:42 PM
sweet bet ya got it cheep to lol

longhorn
12-04-2011, 11:36 PM
Piece of shit dont smoke anymore but now its got a bit of a miss.

I put in new plugs and wires.
Half the pollution crap is unhooked would that make it miss?

I unplugged the MAP sensor and that seemed to help?

4skin
12-05-2011, 02:34 AM
one thing those fi 300 sixes are bad for is the tabs breaking on the intake
where it bolts to the head
causes vacume leak
been awhile but i think the manifold bolts are only 18 inch lbs or less
try spraying some carb cleaner or something around the base of the manifold
if it smooths out youve found the problem
how doi i know this think book time is 5 hrs
j had it down to 20 min re @re wish i was getting paid to do it and it wasnt minelol
and yes that polution crap being unhooked or hooked up wrong could cause it to miss
does the motor hunt or surge at idle?

longhorn
12-05-2011, 08:55 AM
Runs good at a idle.
I can feel it hicupping going uphill when it has to lug some.

Are you talking intake nmainifold or exhaust manifold?

Hellboy
12-05-2011, 09:08 AM
Runs good at a idle.
I can feel it hicupping going uphill when it has to lug some.

Are you talking intake nmainifold or exhaust manifold?

one thing those fi 300 sixes are bad for is the tabs breaking on the intake
where it bolts to the head
causes vacume leak
been awhile but i think the manifold bolts are only 18 inch lbs or less
try spraying some carb cleaner or something around the base of the manifold
if it smooths out youve found the problem
how doi i know this think book time is 5 hrs
j had it down to 20 min re @re wish i was getting paid to do it and it wasnt minelol
and yes that polution crap being unhooked or hooked up wrong could cause it to miss
does the motor hunt or surge at idle?


:dontknow:

4skin
12-05-2011, 09:58 AM
yes the intake pita with the exhaust
but with it idleing ok
it probably isnt a vacume leak
if you have a compresion gage test it
saves alot of guessing