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1990 f150 302 manual 4x4 lariet
so the truck has started using up the coolant.
no steam from exhaust, no drips and runs perfectly.
so need this truck right now so i have been filling up the expansion tank with straight water .
goes about 20 miles half gone.
so then looped the heater hose and put in my spare known to be good radiator.
still gobbling up the coolant.
no idea where it’s going ….yet
then I threw in 3 of these …did absolutely zero….ha ha
have to decide what next. Crushed walnut shells and some other stuff it list on the back
Last edited by rocketroy; May 24, 2026 at 02:43 AM.
Reason: Incorrect title
Few places to look, check engine oil on dipstick, weep hole on water pump and look for puddles on the top lower parts of timing chain cover. I know it’s not cheap, but if you are refilling that much, straight water is not good for heat dissipation.
You can also buy the uv dye kit, run it and then find the leak that way.
freeze plugs as well. Side of block and back/front of heads.
found a pin hole leak after you instructed me where to look.
thankyou so much.
i think I’m going to replace all of the smaller diameter hoses.
I can’t believe how many there are once you remove the air intake hoses.
i have no idea where to get the pre shaped ones.
thanks again
Should be a 1/8" NPT at temp sensor, I would plug it and where ever the thing routed to...someone can tell you as I did forever ago.
Honestly cannot recall as my aftermarket coolant gauge sender is there! I recollect it routed through the throttle body and perhaps the output went to the radiator?
Recommend fresh hoses while apart, unless they are already fresh.
i have no idea where to get the pre shaped ones.
thanks again
The only preformed one I could find was the water pump to thermostat housing. For the throttle body hoses I had to use bulk hose.
Originally Posted by Hit Man X
Should be a 1/8" NPT at temp sensor, I would plug it and where ever the thing routed to...someone can tell you as I did forever ago.
Honestly cannot recall as my aftermarket coolant gauge sender is there! I recollect it routed through the throttle body and perhaps the output went to the radiator?
Recommend fresh hoses while apart, unless they are already fresh.
1/8” NPT hose?
The hose from the intake goes the lower port on the throttle body. The top port either goes back to the radiator or is T’d into a heater hose.
No, the little tit at the that intake manifold adapter for the heater core output hose that also retains the CTS sensor...
Where did I state 1/8" NPT hose?
Okay and I was correct about its routing after deleting it near 30 years back on my 88. Just bypass it and motor on. Local hardware stores sell small plugs and whatever is needed for the radiator, probably a small rubber plug.
Last edited by Hit Man X; May 25, 2026 at 01:40 PM.
He did not, I was telling him to just bypass it and not worry about finding that hose
OR
Could just run a hose from that tit right to the radiator or heater hose adapter. Either solution is quick, plus easy and he will have to service the cooling system post haste as apparently water only
I just got new hoses from a local shop and he found many of them pre shaped and factory, excluding the 5/8 heater core hoses he found all the others in the right shape and size..
so I’m doing the lot.
im also going to the marine store to buy stainless smooth hose clamps as they ain’t that expensive and will out live the truck…oh and they are made in the USA so not crap.
once all the small ones are done, I take in the 5/8 and we cut and size them by the foot from the drum.
the pin hole leak was literally mini steaming the temperature sensor plug, so take that off and make sure the contacts are not green.
then should be golden.
slowly working my way around this truck.
eventually, 3 g alternator conversion and 4 hole fuel injectors …
thanks guys m much appreciated…..Roy
