Testing the Temperature Sender Unit , 400 M .
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From: Okanagan BC
Testing the Temperature Sender Unit , 400 M .
My truck is an 80 Ford F250 4x4 , 400M , C6 . The temp. gauge isnt working and I was wondering if anyone knew how to test the temp sending unit to see if its the problem . I want to check that first . Is it an ohms reading or ??? Thanks for any help !
Jeff
Jeff
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From: Indiana
Testing the Temperature Sender Unit , 400 M .
You can test the factory gauge quickly by grounding the wire that goes to the sending unit with the igition key turned forward to the run position. It will fully peg the gauge. If the gauge pegs, then its (the gauge) fine. Its your sending unit thats bad or its not grounding good to the block. Yes it would be an ohm check on the sending unit but I don't know what the values would be. As resistance (temperature) increases it would move the gauge over more into the operating range. 
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From: Okanagan BC
Testing the Temperature Sender Unit , 400 M .
Ok thanks , I`ll check that out today . You ever have to replace the exhaust manifold gasket(s) on a 400M ? I have a couple friends with them and they all seem to leak ( like mine ) on the passenger side of the engine . Even my Buddy`s 460 leaks like mine . It`s just I`ve heard horrific stories of busting the studs etc... Mine do look a little scary . Any tips , suggestions ?
Jeff
Jeff
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From: Indiana
Testing the Temperature Sender Unit , 400 M .
Are you meaning leaking between the exhaust manifold and the head or leaking where the exhaust pipe fastens to the exhaust manifold? Either one, try to soak them with a good penetrating oil such as PB Blaster for a couple of hours or longer before you try to wrench on them. This PB Blaster has saved my bacon many times. Let me know which type of leaking your wanting to fix.
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From: Okanagan BC
Testing the Temperature Sender Unit , 400 M .
Hi
I just bought the truck a few days ago and have been busy replacing plugs , wires , belts etc..( it still had the original alt. belt on it ) and now thats done I`ll get my stethoscope out and listen around the manifold , thats where I suspect it is coming from . I`d be happier if it was the pipe . I hear quite a few Fords with that same "tick , tick , tick " . I`ll let you know later what my findings are . Thanks !!
Jeff
I just bought the truck a few days ago and have been busy replacing plugs , wires , belts etc..( it still had the original alt. belt on it ) and now thats done I`ll get my stethoscope out and listen around the manifold , thats where I suspect it is coming from . I`d be happier if it was the pipe . I hear quite a few Fords with that same "tick , tick , tick " . I`ll let you know later what my findings are . Thanks !!
Jeff
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From: Indiana
Testing the Temperature Sender Unit , 400 M .
[updated:LAST EDITED ON 30-Aug-02 AT 03:36 PM (EST)]XJeepGuy, You could have an exhaust leak. But is there a chance the tick, tick, tick, you are hearing is a rocker arm? The 351M and 400 enginges were bad about that. The rocker arm gets some wear where the fulcrum rides in the top of it, and it gets a little sloppy and results in noise. The pushrod ends wear on these too and where they ride in the rocker. I have seen these vary from very loud clacking to just a little tick sound depending on the wear.
Not saying its your problem, but its a good place to look.
My experience with the 351M's, & 400 is, if the motor has not been distrubed, the 400 used no gasket between the head and exhaust manifold.
Not saying its your problem, but its a good place to look.
My experience with the 351M's, & 400 is, if the motor has not been distrubed, the 400 used no gasket between the head and exhaust manifold.
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From: Okanagan BC
Testing the Temperature Sender Unit , 400 M .
Hi Dave
I had a good listen today and its an exhaust leak for sure .I still havent pinpointed where its at .Hard to see on the pass. side with that cover over the exh. manilfold that routes the pipe to the air cleaner intake . I`ve been doing little preventative maintenance items on it all day , new solinoid <sp?], battery cables , rad flush etc... It doesnt look like there are any gaskets in between the exhaust manifolds and the cyl. head . I bought the truck off an older gentleman who used it for vacations and and its only got 40,000 original miles on it so I didnt think it would be worn rockers
Anyways , thanks for the tips and stuff and I`ll let ya know what I find .
Jeff
I had a good listen today and its an exhaust leak for sure .I still havent pinpointed where its at .Hard to see on the pass. side with that cover over the exh. manilfold that routes the pipe to the air cleaner intake . I`ve been doing little preventative maintenance items on it all day , new solinoid <sp?], battery cables , rad flush etc... It doesnt look like there are any gaskets in between the exhaust manifolds and the cyl. head . I bought the truck off an older gentleman who used it for vacations and and its only got 40,000 original miles on it so I didnt think it would be worn rockers
Anyways , thanks for the tips and stuff and I`ll let ya know what I find .
Jeff
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From: Okanagan BC
Testing the Temperature Sender Unit , 400 M .
Superdave
Hi , how are ya ? Well I said I`d let you know what I found as far as the " tick tick tick " supposed leak goes . Well... it turned out to be that little plate on the intake manifold that the tubes come out of to heat the choke . There was a pencil diameter sized hole in that plate . Condensation and rust through the years I guess wore through it . Mixed up a good batch of JB Weld and the leaks gone . With the echoes in the engine compartment it was hard to tell but I noticed it was darkish around there so that was that
Thanks for the Help
Jeff
Hi , how are ya ? Well I said I`d let you know what I found as far as the " tick tick tick " supposed leak goes . Well... it turned out to be that little plate on the intake manifold that the tubes come out of to heat the choke . There was a pencil diameter sized hole in that plate . Condensation and rust through the years I guess wore through it . Mixed up a good batch of JB Weld and the leaks gone . With the echoes in the engine compartment it was hard to tell but I noticed it was darkish around there so that was that
Thanks for the Help
Jeff
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