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Discussion Starter · #1 ·
I posted up about this before but im still not sure.

I took my thermostat out to try illuminate air lock from my theorys.

If i start my ford 460 and let it runs for a bit and give it some revs the radiator hoses gets massive pressure like when u shake a can of fiz up and u squeeze it its really hard and looks like they guna blow so i turn the engine off was only running for about30seconds the hoses were warm so i left it all day so like 5 hours came back the hose was squeezable and not rock solid but when i still took the radiator cap off all this cold was blew out like it does when taking the cap off a hot radiator, i took the spark plugs out to check, 1 pluged looked cleaner then the others which makes me think cracked head or head gasket but then again they are only new plugs which have only done like 3mins worth of engine running, but the other plugs had blackness on them like normal just the 1 was cleaner :( but i done a compression test firstly on the one i thought was stuffed but all cylinders are 140 psi give or take a few psi but compression tests dont show cracked head etc. . . .

Mechanic hasnt got one of them things u put over the radiator to check for exhaust gasses etc.


Can anything make radiator pressure extremely high other then a cracked head or head gasket? i have no idea what to do im stuck worrying iv only just got the car so have no idea about history or anything.

oh i also borrowed a radiator cap from my friend to try tomorrow incase it was my radiator cap but surely the water cant get pressure in the radiator anyway . . .


oh and if i have a cracked head or head gasket and water is getting into the cylinder which made the spark plug cleaner then the others, wouldn't that make it lose water see water will be seeping out into the cylinders not pressurizing it or wouldnt it make steam or something come out the exhaust? the only stuff that comes out the exhaust is sometimes it gets a puff of blue/black smoke but i thought that was because it has a 750 holley on but isnt tuned so running rich or something because it doesnt run 100% and i duno how to set a/f ratio i googled how and when i turn the screws its ment to rise in rpm or drop but i can turn the fuel mixture screws all the way in and then out and the engine doesnt change in idle rpm, it runs good when u open the throttle but when u try sit at a constant rev above idle it will miss and run like a bucket which i thought is the carby because iv replaced plugs put new leads a new hei dizzy done timing etc but only thing i havnt done yet is tune the carby.

sorry about the book =[ just trying to give as much info as i can so hopefully someone will give me something new i can try to find the problem
 

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Discussion Starter · #2 ·
havnt got a reserve tank for it yet and i did have it running when i filled it up, im going to get a bottle fill it half with water and tape it ontop of my radiator and start it so i can watch what happens and see if theres any bubbles or if its just moving up and down, will do that shortly
 

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Discussion Starter · #3 · (Edited)
there were no major bubbles coming from it but as it heated up it let like 4litres of water out the overflow then when i turned it off it sucked it back up, i know thats what its ment to do but like 4liters? aint that to much? temp gauge was only reading around 80 degrees Celsius,

i checked spark plugs again well just 2 1 that i know is good but on nuber 6 plug its always cleaner then the rest and number 6 is the cylinder that is missing . . . what else could cause jst numer 6cylinder to miss, timing/carb a/f mix wouldnt do that would it? i thought it would effect all cylinders not just the one, also number 6 cylinder puffs the odd tiny bit of blew smoke

i put a clear hose on the overflow so i could watch the water pour out as it got hot and the water was straight water with like no air bubbles or anything either
 

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Discussion Starter · #4 ·
i jst brought new plugs and gapped them to .044 and a brand new hei dizzy and new leads but ill swap the leads over now im jst about to double check my timing im going to do a leak down test tomorrow on 6th cylinder to try see if i have a cracked head
 

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Discussion Starter · #5 ·
just redone my timing and i found the reason all that water poured out was the radiator cap wasn't sealing 100% but if it seals the hoses get to much pressure so i think its just the cap . . . ill know tomorrow for sure getting a leak down test done to find out if i have a cracked head or not. fingers crossed for me please i have terrible luck haha i hope its not broken.
 

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Discussion Starter · #6 ·
hoses are new so had nothing on them and yeah i thought the cap would let off as wel but not seeming to work

its a brand new alloy radiator and cap too unless it was just a faulty cap from new iv tried others but sort of still the same thing happens
 
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