351M Overheating Problem.
Isaac Davis
I am having a problem with my 78 F150 4X4. When the temperature goes
above about 85 - 90 degrees here, I have to pull over due to overheating.
This engine was rebuilt about 6 years ago, and I have been fighting the
heat ever since. For 3 years, I didn't really drive it hard in the
summer, but lately I have been driving it back and forth to work every
day, about 50 miles each way. I have put a new 4 core radiator in, and
have put about 5 different thermostats in. Still, no luck. I can't even
think about running the ac, or the temperature guage starts rising. When
I was pulled over today (97 degrees outside), I put my thermometer in the
radiator coolant, and it showed that the coolant was about 204 degrees. I
am not sure, but I think this is pretty hot. I have heard from a mechanic
that with the 351M/400 engine, you can put the head gaskets on wrong, and
they will bolt up perfect, but you plug up some of the water holes. He
also stated, that usually when this happens, pressure builds up, and it
blows the radiator hoses off. I don't have this problem though, and I
seems to run within temperature range on cooler days. Also, I do have a
fan shroud, and have a flex fan pulling the air through. If anyone has
any suggestions, I would really appreciate the help. This is driving me
crazy.
Thanks
Isaac Davis
ida...@comland.com
Paul
Have you replaced the radiator cap? it's easy to overlook. If it couldn't
hold the proper amount of pressure (5-17PSI depending on the system) it
would vent steam at a low temperature (204 Deg. F). This temp isn't
all that bad. I run 190 degree thermostats in all of my vehicles so I assume
the temps. easily get up to 200 to 205.
In what I said above, I'm assuming that when you say overheat, your getting
steam out of the radiator cap. If not, you may be judging by
your temp gauge. This brings up other questions. If your temp gauge
is reading "HOT" but the enginge coolant temp is 204 degrees, It could be
that the gauge sender (the unit that threads into the coolant jacket in the
engine, usually on intake manifold) is not the correct one for you vehicle and
is giving an improper reading. In other words, It's saying that the engine is
hot when it is really at standard temp.
The head gaskets could be a problem, but I would expect the engine to ping
really, really bad. If the heads were getting no coolant, they would overheat,
this would result in many hotspots inside the compression chamber, this leads
to early detonation of the fuel charge(Pinging).
I hope this helps,
Paul
Mark A Zimmerman
: am not sure, but I think this is pretty hot. I have heard from a mechanic
: that with the 351M/400 engine, you can put the head gaskets on wrong, and
: they will bolt up perfect, but you plug up some of the water holes. He
: also stated, that usually when this happens, pressure builds up, and it
: blows the radiator hoses off.
Yes, you can and it'll overheat. I did it once on my dad's '78 and
wound up pulling the heads off and putting the head gaskets on correctly
(with much embarassment on my part). We never blew any hoses though, it
just ran hotter than, well, it ran hot.
Mark Zimmerman, Central Wisconsin
Roy Gass
I have the same problem (changed radiator, thermostats, etc..).
I did get more accurate readings by replacing the sending unit.
It was actually running a little cooler than the gauge showed. I didn't
replace it sooner since I have an additional temperature gauge which
drifted up at the same time as the stock gauge. But, now, it is creeping up
again.
The only difference from your description is mine is a '79.
I would love to hear of a solution.
Thanks,
Roy
>In article <4nr2mg$l...@kermit.comland.com> Isaac Davis writes:
>I am having a problem with my 78 F150 4X4. When the temperature goes
>above about 85 - 90 degrees here, I have to pull over due to overheating.
> This engine was rebuilt about 6 years ago, and I have been fighting the
>heat ever since. For 3 years, I didn't really drive it hard in the
>summer, but lately I have been driving it back and forth to work every
>day, about 50 miles each way. I have put a new 4 core radiator in, and
>have put about 5 different thermostats in. Still, no luck. I can't even
>think about running the ac, or the temperature guage starts rising. When
>I was pulled over today (97 degrees outside), I put my thermometer in the
>radiator coolant, and it showed that the coolant was about 204 degrees. I
>am not sure, but I think this is pretty hot. I have heard from a mechanic
>that with the 351M/400 engine, you can put the head gaskets on wrong, and
>they will bolt up perfect, but you plug up some of the water holes. He
>also stated, that usually when this happens, pressure builds up, and it
>blows the radiator hoses off. I don't have this problem though, and I
>seems to run within temperature range on cooler days. Also, I do have a
>fan shroud, and have a flex fan pulling the air through. If anyone has
>any suggestions, I would really appreciate the help. This is driving me
>crazy.
>Thanks
>Isaac Davis
>ida...@comland.com
>>
AT&T Global Information Solutions
Roy Gass
Roy....@ColumbiaSC.ATTGIS.COM
(803) 939-2293
Muskie
I have the same problem (changed radiator, thermostats, etc..).
I did get more accurate readings by replacing the sending unit.
It was actually running a little cooler than the gauge showed. I didn't
replace it sooner since I have an additional temperature gauge which
drifted up at the same time as the stock gauge. But, now, it is
creeping up
again.
The only difference from your description is mine is a '79.
I would love to hear of a solution.
Thanks,
Roy
often to seriously consider! it amazes me that you guys put up
with this junk from ford!! maybe ford should
have put a sticker on the truck saying "do not drive in summer
or at temperatures over 80degrees" what a joke! how do you deal
with garbage like that????----muskie
Jeff Lindner
< Here is your solution roy, dont buy ford! they overheat way
< too
< often to seriously consider! it amazes me that you guys put
< up
< with this junk from ford!! maybe ford should
< have put a sticker on the truck saying "do not drive in
< summer
< or at temperatures over 80degrees" what a joke! how do you
< deal
< with garbage like that????----muskie
< Muskie,
You are about a little prick.
You don't know anything about vehicles. Ford has traditional
had larger cooling capacites than GM. Ford has also had higher
GVWR than GM. Ford has out sold GM in the United States for
19 consective years. They have always been better work than
GM products. GM products are nice vehicles, but they are more
of a sport truck.
We have over 4000 acres of land down here in Texas, and we have
had both GM and Ford. And the Ford have always held up better
in the long run. We used to pull 7.5 tons with our half ton
Fords. I get tired of listen to ya'll city slicker who do
nothing but drive around looking 'cool'. Why don't you put
some weight behind that Yukon and then keep it around for 10
years or so, and then you might have something to talk about.
Here is a few reason why I think Ford is a better work truck
than GM.
- GM recommends not pulling in overdrive (automatic trans).
Ford and Dodge trucks you can.
- GM still uses a TBI injection (which is a hybrid), while Ford
and Dodge use a true multi-port fuel injection.
- GM uses a singe tac-weld and epoxy to hold the doors on.
Ford and Dodge still bolt theres on. Don't tell me you
haven't heard of GM doors falling off!
- GM doesn't bolt there beds on either. They been known to
break loose after years of use.
- They use aluimun drive shafts on some of there half tons.
- Lets talk about GM diesals too. Sure they've fine motors.
Converted gas motors that were completely junk.
- GM interior are really nice inside, but there is so much
plastic inside. I'll take that GM down to our ranch and I'll
guarantee I'll have the dash just a rattling. Ford and Dodge
hold together better.
I know why they call you Muskie, because you are full of
'shit!'
Next time, when someone post a message in the news group don't
be such a little penus!
Jeff
MCPGroup
Roy Gass wrote:
>
> I have the same problem (changed radiator, thermostats, etc..).
> I did get more accurate readings by replacing the sending unit.
> It was actually running a little cooler than the gauge showed. I didn't
> replace it sooner since I have an additional temperature gauge which
> drifted up at the same time as the stock gauge. But, now, it is creeping up
> again.
>
> The only difference from your description is mine is a '79.
>
> I would love to hear of a solution.
>
> Thanks,
> Roy
>
First I would ask you both what you are and have been running for
coolant, next at anytime have you ever added a can of stop leak to your
system? sometime this stop leak stops more than leaks it plugs the
heads just enough to cause insufficant cooling. The head gasket could
still be a problem IF when it was installed it wasn't done right, in
fact Roy I would almost bet thats where your problem lies, I'm working
on my 351 M right now and had to put a set of pushrods in it, it's an 80
model and I need to get vacuum hose hookups figured out since the
previous onwner took them all off, my be you guys could give me a few
answers in that reguard otherwise I'll have to go through all my manuals
for the Bronco and figure it out. the 351 M is a great motor, I would
really take a look at the heads they maybe close up with rust, did they
tank the heads and do a complete head rebuild or just grind the seats
and reinstall the old parts? just a few thoughts I'll look up what the
factory manuals have to say about it tommorow
Reguards
Mark
Mike Grant
In article <4o3n98$9...@nemesis.ntsource.com>, mi...@mail.ntsource.com
says...
>
>
> I have the same problem (changed radiator, thermostats, etc..).
> I did get more accurate readings by replacing the sending unit.
> It was actually running a little cooler than the gauge showed. I didn't
> replace it sooner since I have an additional temperature gauge which
> drifted up at the same time as the stock gauge. But, now, it is
>creeping up
> again.
>
> The only difference from your description is mine is a '79.
>
> I would love to hear of a solution.
>
> Thanks,
> Roy
>
>often to seriously consider! it amazes me that you guys put up
>with this junk from ford!! maybe ford should
>have put a sticker on the truck saying "do not drive in summer
>or at temperatures over 80degrees" what a joke! how do you deal
>with garbage like that????----muskie
>
Ever thought of replacing the 351M, Roy? I had the same problem with my
400M, add to the fact of bad gas mileage and lack of power. I decided to
swap engines and opted for a 429. Now my mileage has gained 2mpg and not
a hint of over heating, even pulling a 10,000 lbs load, up a 8% grade in
110 degree heat! The engine uses the same radiator, guage, and sending
unit the 400 had. I also guarantee that the 429/460 series engines will
outlast and outpull anything muskie recommends, short of a Peterbuilt.
For more engine swap info contact L+L Products, (214) 475-5202. ---MG
P.S. I deal with that junk by passing the competition with it!
Muskie
heeee haaawwww jeff lindner! heeeeee haaaaaaawww!!
your mighty right there fella, my wifes baby come out
sideways. were headin to meet the train at st-t-t-tubville.
get an education you moron. just because you have a hick
accent doesnt mean you cant type in english.your ford bites.
you stupid flag waver!! heeee---haaaaawww!!!------muskie