[funfool]

I am kinda baffled here with my cooling system on my work truck. It is a 1987 E250 with a 351, I have had it for almost 10 years and plan to keep it for another 10.

Last winter the heater core started leaking and needed to replace it.
Before replacing it, the heater was awesome, I mean up in the mountains in snow and had to turn the heat down to medium... toasty warm.
With the new heater core, It only warms enough to take the chill off, just sucks.

My real question is, would it matter if I reversed the heater hoses?
I did change the heater hoses at the same time, I believe I got them back in same location, but just makes no sense why it does not heat up. It blows warm air out, then the air turns cold, then gets warm for a bit and then cold again.

I do not know, but do not think if the hoses were reversed would matter.

 

[Bondo]

Ayuh,... Switch 'em, 'n Try it.....

Donno if you've got any vacuum valves in the dash, or under the hood,...
My '96 does...
They're worth checkin' out,...

 

[joecaption]

I see no way it should matter. It's nothing more then a mini radiator.
I agree could be as simple as a leaking vacuum line, or an air lock.
May want to check this site out.
http://www.ford-trucks.com/forums/672215-coolant-airlock.html

 

[funfool]

no vacuum valves,
And you know I wrote the post above, I thought to myself, I could have switched them and tried it in the time it took to write the post.

Just kinda stuck at my desk right now and thought I would ask. I really think I got them back in the same location, but have been wrong before.
So if I do switch them, I will now think they are backwards .... but again, does it really matter?
I will find out soon, going to take the wife to dinner in the work truck soon, she will be pleased once I get all the plumbing parts, paper work and laptop off of the passenger seat. :laughing:

 

[DexterII]

I can't think of any reason that reversing them would cause that problem either, and would be more inclined to agree with the linkage; either a loose, kinked, or ruptured vacuum line, or a pinched cable. I had one one on one of my Dodge Ram's that I chased for a couple of weeks before finding a little piece broken off of a small ear on one of the plastic linkage clips that prevented one of the doors from opening all of the way. Something like $2 and a lot of cussing before I got it worked back up in there, and it was fine after that. If it's cables, hold your hand along the sleeve while operating the lever, and sometimes you can feel the whole thing flexing when it starts to bind. If vacuum, I have used a hand vacuum pump to isolate the problem. A bit of a stretch, but you might even want to pull a vacuum reading off of the line that goes to the controls, although you would probably realize a leaking intake manifold in the engine performance.

 

[funfool]

Joe, nice find, :thumbsup:

I will check there and maybe even join and make a post.
Thing is, it was fine one day and then change heater core and no heat the next.
Since then I have changed water pump, radiator hoses, T-stat, and flushed the system.
I have a connector in the heater hose to connect a garden hose to and remove the radiator cap and let it run. I also added a chemical flush to the system and followed the directions.
At this point a airlock is all that makes sense, but that was a year ago, think it would work its way out by now.
But since I have worked on the cooling system many times since then and never burped it ... who knows?

 

[rusty baker]

Did you change the hoses, too? I have seen them collapse inside and it didn't show on the outside.

 

[ukrkoz]

air bubble. you need to bleed system with heat on full throttle. Fords have to have it done 3 times in a row and with pass side on the incline.
Be well stay warm.

 

[firehawkmph]

Agree with above post. Sounds like you still have air in the system. My old timer buddy's dodge was doing the same thing, except he hadn't changed the heater core. My son is a tech at a local dealership and does work for friends here at home. He told him to hold off on the heater core and let him check it out. This is after he had it to an automotive repair shop already who changed the thermostat and flushed the system. My son found they had mixed two different antifreeze's which didn't mix and still stayed separated in the system. After flushing it, he let that truck run for 15-20 minutes with the cap off and mid throttle. Even after 10-15 minutes, you could still see big air bubbles burping up. After he got done, he sealed everything up and had good hot heat like it was new again. That was before last winter and it's still doing fine.
Mike Hawkins

 

[Bondo]

Joe, nice find, :thumbsup:

I will check there and maybe even join and make a post.
Thing is, it was fine one day and then change heater core and no heat the next.
Since then I have changed water pump, radiator hoses, T-stat, and flushed the system.
I have a connector in the heater hose to connect a garden hose to and remove the radiator cap and let it run. I also added a chemical flush to the system and followed the directions.
At this point a airlock is all that makes sense, but that was a year ago, think it would work its way out by now.
But since I have worked on the cooling system many times since then and never burped it ... who knows?

Ayuh,... I didn't say it in my 1st post,...
But generally there 2 different sizes hoses,...
Either 1/2", 'n a 5/8", or a 3/4"....

The line that Pushes the water to the heater will come out of the block, head, or intake manifold, behind the T-stat...
The return line will dump into the circulatin' water pump, or a radiator hose "T"...

 

[Billy_Bob]

The test is to warm up the engine, then see if both hoses going to the heater core are hot. That means hot water is circulating through the hoses and heater core.

Might want to compare with another vehicle - see how hot those hoses are.

If they are not hot, try removing the hoses at the engine, placing a garden hose on one end, and seeing if water can flow through the hoses and heater core.

Next check your engine temperature. Look at the gauge on your dash. If it is running much more cool than before, then the thermostat could be installed backwards or stuck open or be too low of a temperature. Check a factory service manual for proper installation and factory spec. temperature of the thermostat. If it is always circulating water through the radiator full blast, the engine coolant will not get hot enough. The water going to the heater core will not be hot. The thermostat closes or only opens partially on very cold days to keep the engine hot (ideal running temperature).

If the water is hot going to the heater core, then check inside the vehicle for an air flow problem. Something is not allowing the air to flow through the heater core when you set it to hot. Maybe forgot to connect something? A flapper is not adjusted right if a cable. Or an electric actuator was not connected or damaged. (There would be some sort of flapper to direct or not direct the air through the heater core depending on if you have heating selected on the dash controls or not.)

 

[paintdrying]

My money is on an air bubble. These are all very good suggestions. I believe you have the formed hoses that are quick connect, impossible to disconnect, but that makes no difference if you mixed them up

 

[ukrkoz]

My money is on an air bubble. These are all very good suggestions. I believe you have the formed hoses that are quick connect, impossible to disconnect, but that makes no difference if you mixed them up

If you talking about Ford infamous quick DIS connect coupling, there's special tool, looks like scissors, for those. $19 or so any parts store. AC, fuel and heater quick disconnect couplings. Total pita to work with.
This thread been going on with idle guesswork for long time. In that time, he could have had his system bled 25 times and more. :whistling2:

 

[rusty baker]

This thread been going on with idle guesswork for long time. In that time, he could have had his system bled 25 times and more. :whistling2:

But where would the fun be in that?:laughing:

 

[funfool]

One thing I like about this old ford, is only a computer of sorts to control the distributor, has a holley 500 4barrel, no emissions installed and does pass emissions testing.
No fancy hose connections or vacuum crap, Is all old school and easy to work on.

I did try to get air out when I first installed the heater core. Went as far as parking it on a hill so the radiator cap was at the high point. That did no good and blamed it on a lousy aluminium heater core, while the old one was brass or copper.
The link Joe gave me, suggested manually burping it.
This is something I never heard of or tried, rained all day yesterday, am going to try it now in a few min.

 

[paintdrying]

I used a wood chisel and hammer to remove those quick connects. Then i used hose clamps and fished the hoses in through the truck. I then used plumbing fittings to flare out to the 1 inch and a half fitting on the block. Between buying those hoses and the disconnect toll I save a lot of money. Did you feel the hoses to see if they were hot? I am glad to hear your truck is all old school. The computer control trucks get better mileage, but they never seem to stay running properly.