Truck refuses to pull water from reserve

[adam123]

Ive got a work truck (1990 f-150 302) that refuses to take any water from the coolant reserve. It'll get about midway on the gauge and push some coolant out and it'll never take it back. The hoses will collapse from the vaccum inside the cooling system when it's cool, And when I take the radiator cap off I almost have to pry it off because of the vaccum inside the radiator. Any idea's ?

 

[tom slick]

replace the radiator cap and check to make sure the hose to the reserve tank isn't clogged. My guess is the radiator cap's check valve is stuck.

 

[adam123]

I'll replace the radiator cap and see what happens the line isn't clogged any if I take it off I can blow straight thru it with no resistance.

 

[Chris142]

A sucked closed hose points to a bad cap or the wrong style.

 

[obbop]

Coot says.....

replace the hose!!!!

If it collapses surely there is pressure differential present.

If so, the collapsed hose is shouting out that "I am the problem!!!!!"

Well, perhaps another component in the suction stream or a contaminant blocking the fluid flow.

Coot recommends.....

Flush entire cooling system. Replace hose. Ensure reservoir is clean, contaminant free.

Then, see if the dern thing works!!!!!

If it does, jump up and down, shouting with glee!!!

 

[Drew99GT]

New cap; my Mom's car was doing the exact same thing a few weaks ago. The rubber seal on the cap was worn and sticking to the filler neck on the radiator.

 

[adam123]

It was the radiator cap. The hoses themselves were brand new. This truck has had so many cooling system issues its not even been funny. Ive fluished the system twice with the prestone cleaner and it comes out Burnt orange from rust everytime. Its had two water pumps on it now. The orginal one failed shortly after I got it. The 2nd one failed because of a weak pulley shaft and now the 3rd one, So far atleast has been working. Not to mention the thing has tried to overheat countless times So I eventually pulled the T-stat. The enviroment that it works in tho is extremly rough on the cooling system. This truck is often used to transport wood from the base of hill to the top for building a log cabin and its often loaded down to its max capacity while climbing an increbily steep hill for about 10 minutes all while the engine is basically screaming. But hey thats why I bought it and its why I love these old trucks their tough as nails.

 

[Trucku]

I thought pulling the T-stat was a no no?
Maybe your thermostat was the wrong spec for the truck.
A bad fan clutch will make you over heat if it won't allow the fan blades to match engine speed.

 

[adam123]

Nah I bought the t-stat as a 180 for the winter when I drove it. It does fine everywere else except this summer since Im using it to tow really heavy loads. Ahh trust me the clutch fan is fine. I changed it out at most a month ago. (Ive redone almost the entire cooling system). It's just the slow speed, Heavy loads, and steep inclines which work together to get the engine hot. Im a little over 1/2 way on the gauge when I get to the top of the hill. Come down and shell cool off and I'll do it again. Somedays when its been really hot this spring its went to about 3/4's but with these old 302's its not really worring.

 

[Trucku]

Your basically working it to its limits...LOL I hear ya.

 

[onion]

While I think that synthetic motor oil is an unneccesary waste of money in most cases... this is an application where I think it'd be a good idea. Sounds like you're working the hel1 outta that little 302. Synthetic will hold up to the excessive heat better.

My Dad told me once when I was a youngun:

"A 302 won't fall out of a tree... won't pull the hat off yer head."

heh.

 

[adam123]

Its got shell rotella Syn in it (5w40) I change it pretty reguarly actually. The people who had this truck before obviously abused it (No maintenance). OD in the Transmission refuses to work but all the others engage perfectly. To be honest thats the only thing wrong with the thing that I know of now. I got the truck for free because the people who had it ran it till it died and were going to scrap it. Turned out it just need a new coil wire. Amazing when you think about it.

 

[adam123]

I appreciate all the responses btw.

 

[Trucku]

It awesome when you get a freebie and even better when it was something as minuscule as that to fix it...

Slap some over sized oil and transmission coolers on her for extra protection. If you put a small electric fan on the oil cooler you may help carry some of that heat load away from the radiator.

 

[Chris142]

The "on hold" thing on our phone talks about the upper hose being sucked shut.

 

[The_Jeff]

I looked at a truck like yours and the previous owner mentioned he had to replace a fuse to get OD working. Not sure if you'll ever reach a speed to need this.

I then pushed the "OD" button on the end of the shifter and smoke started coming out.

Also the thing was... yup... leaking antifreeze. Total neglect-mobile.

If you like hillbilly repairs you can probably lock the fan clutch so it's 100% all the time. Put quite a load on the belt, and if you redline it the fan might disintegrate, throwing blades everywhere. But no other drawbacks I can currently imagine.