heater hose: install restrictor?

[BerniniCaCO3]

Hi!

I'm cleaning up a 1989 colony park for my sister; we've put nearly a thousand into parts....
Anyway!

I'm doing the coolant hoses RIGHT NOW. All of 'em.
Now, there's a long one that goes from the thermostat housing back to the heater core.
OEM has 2 hoses with a restrictor in it.
New from NAPA is just one hose.

Do I want to slice that hose and install the restrictor?
Or, leaving it out, might we actually get more heat out of the heater core?
The risk as I've read is that the heater core can blow.

Does it matter which direction the little restrictor faces (I didn't keep track when I cut the old hoses off)?

My sister is a lead-foot, but, there will be no modifications to this engine and it will rarely see the high side of 3000rpm and never the far side of 4000rpm, if my own colony park with its tachometer on it is any comparison. Granted, she's got the 3.55 rear... for just 2 more days ;-)
So if she's going to get more heat with the straight hose and it's unlikely she'll blow the heater core... versus, if even 3000rpm can be a danger to an antique heater core without the restrictor, and I really ought to put that in there.

Let me know ASAP! Like in the next hour-two. Gonna go do the 2nd O2 sensor and spark plugs while I wait for your advice

[BerniniCaCO3]

speaking of O2 sensors, good GRIEF that passenger side sensor is insane!! Only just cracked it loose....whew.

[gadget73]

the restrictors are to keep the heater core from exploding when you throttle it down. Retain them. Flush the core out with a garden hose if you're not getting decent heat. Its probably half plugged with crap. Might be worth running a cooling system flush potion in there if the coolant ws really nasty.

[1990LTD]

reverse flush the core too

[sly]

reverse flush the core too

x 2000

I had to do this on my Lincoln to get heat at all. I still need to run some coolant flush through the system as well. it's on the to-do list... but may wait until spring.

[BerniniCaCO3]

I was still taking care of other things and got your advice in time last night, gadget, but then I found that at some point (probably in aggressively removing the fantastically seized hose clamp), the center restriction part of that plastic spacer had popped out! I could not find where it shot off to at all.... I haven't checked yet, but somehow I doubt napa sells replacement restrictors?

The coolant was clean, but, I don't know how recently it had a coolant flush to make it so.
I just sorta thought that you already have 16psi coolant coursing through the water pump, what does hooking up a water hose do more than that?
I still haven't put coolant back in yet, and I've got new hose clamps on the heater hoses so they'll come off easily now. Not too late for a flush! How do you like to do it?

[1990LTD]

I was still taking care of other things and got your advice in time last night, gadget, but then I found that at some point (probably in aggressively removing the fantastically seized hose clamp), the center restriction part of that plastic spacer had popped out! I could not find where it shot off to at all.... I haven't checked yet, but somehow I doubt napa sells replacement restrictors?

The coolant was clean, but, I don't know how recently it had a coolant flush to make it so.
I just sorta thought that you already have 16psi coolant coursing through the water pump, what does hooking up a water hose do more than that?
I still haven't put coolant back in yet, and I've got new hose clamps on the heater hoses so they'll come off easily now. Not too late for a flush! How do you like to do it?

the water pump doesn't run backwards though. scale develops etc and reverse flow will usually break up anything in there that's not supposed to be...also using some kind of chemical flush can be helpful.

[GM_Guy]

Personally, I see no need for a restrictor. Non of my non-fords have restrictors. And the late model gm's with the restricted intake manifold passage usually get a drill put to them when the owners complain about a lack of heat.

BTW, you'll probably end up doing a heater core in the semi-near future, restrictor or not.

Alex.

[gadget73]

I've never seen a need for one either, until I swelled one up and had it pop after running the car at high speed for a while. I also distinctly remember a WOT blast with a 2 month old heater core and no restrictor that ended in a soft "plop" and a big cloud of steam coming out of the dashboard on someone else's car right after the 351w swap. On anything else, I'd agree its stupid. Unfortunately for whatever reason, Fords seem to blow up heater cores if you beat on the car.

[BerniniCaCO3]

Ah. Well, my sister does NOT beat on her car, ever. Which is lame, but easy on heater cores. ...and the restrictor broke, so I'm not eager to locate one at a junkyard (not many boxes here).

We're thinking... the heat seemed to work well on a merely brisk day, but driving it around this past week, it's just not hot enough. Not at all.
So, I just pinch off the heater hoses and remove them, then blast away with a garden hose to reverse flush it? Or is there a special rubber cone to stick on the end of a garden hose?

Or rather than hope that a flush is all it needs (though, the coolant I drained to do the hoses +radiator WAS clean), bite the bullet and spend 6 hours on a new heater core?

[sly]

I used a flush T and plugged the open side and put it on the return line from the heater core. The T has a built in restrictor. I just started easy to make sure fluid would flow... and once it did, I just cranked up the hose and let it flow for a while. I still need to run a radiator flush through it all still though.

[Southern_Pride]

Just t the lines together with a 1/4 inch hose.