Hey all;
First post and proud new owner of an 85 Ford Conversion Van.

Just bought this rig and I've been getting her ready for some heavy traveling.

Took care of a coolant leak and decided to also flush the cooling system.
Did it when the engine was warm, gauge barely below half-way. Fired it up to circulate
I had a momentary lapse of reason, forgetting that filling the rad with cool liquid is not generally a good idea to do with a warm block.
Coolant was hot to touch, but not scalding, just a bit uncomfortable, if that helps any...
Do I have anything to worry about? Been concerned about this now...

-Morgan

 

Chances are better than "fair" you did nothing to harm the engine. It should be a cast iron block and heads which can absorb a lot of "abuse" and survive.

Assuming your thermostat was still installed a relatively cold coolant would cause it to close so it wouldn't be circulated. When you're filling the system the radiator is first to receive the fluid and without the engine running it doesn't circulate.

Additionally the cooler liquid would quickly absorb the block and radiator heat so temperature equalization would also be quick.

Run the van a few days around town just to be sure but I'm betting you're fine now, no potential issues down the road.

 

Jwa, my coolant in my Ford E150 van is 26 months old and ready for a home flush. My Subaru has 2 large drain plugs on each side of the boxer engine. I don't see anything line this on my 4.2 v6. I want t make sure I flush the heater core. What is a good method to flush all or more of the coolant?

 

I've never really done this operation so take this for what it is.....

'Twere it me and this was my concern I'd use enough replacement coolant mix to run it through the block and radiator several times. I don't believe there is a way to thoroughly drain the system to the point its close to bone dry.

Another way is to drain the block, fill it with plain water and let it circulate for a while. Drain again and repeat. After several cycles add the new properly mixed coolant and you should be good to go.

You can also periodically test the pH of your coolant with test strips---should be a ton of info here on FTE in the engines forums or the Heating/Cooling forums.

 

I think a. Urban ghetto flush will suffice. I will drain as you suggest and run the engine withe the heater on to flush the core. I will rinse and repeat several times. Testing the ph is a "mavalous" idea!

 

It doesn't matter if the heater is on or off. The coolant is always running through the heater core- anytime the engine is running.

And Im not fond of JWA's method of flushing with water because that leaves you with unspecified protection when finished.

I suggest filling the top hose with proper 50/50 mix as you drain the old stuff. Flush the radiator a few times with water, but let it drain completely empty.

The only problem I foresee is the cold (new) fluid getting blocked or stopped by the thermostat.

How much do the Ford dealers charge for a coolant flush? It might be worth it to just pay them.

 

It wasn't my intention to suggest that we not test for proper concentration of the coolant/water mix afterward---my bad there.

OP's engine is an '85 and while I can't view one of these at the moment his heating system is probably of that era/vintage meaning it might have a heater control valve intended to stop coolant flow to the heater core. It wasn't until '92 or the blend door and vacuum operated air flow systems were offered.

Flushing out the old coolant via my suggest works wonderfully IF the thermostat is removed first. Because its been over 26 months since last known coolant exchange my ideas would work just fine if only to remove as much of the older coolant as physically possible by any method.

Once the old coolant was sufficiently removed via replacing it with pure water that issue is somewhat solved---now onward to installing the new.

Check and replace any hoses as needed, create the proper 50/50 mix, install a new t'stat (or reuse existing if confident its in good working order) and fill block/radiator with the mix. Open the heater controls or set to full heat, blower on full and start engine. I'd install the radiator cap until the engine is at idle, remove it to watch the coolant level.

Watching the temp gauge as it begins to rise be ready to add some coolant mix to the radiator as the t'stat opens. As the coolant level in the radiator drops add more to bring it back near the top, feel the cabin heating airstream for a temp rise. If no visible hose leaks you're almost finished.

Hold the engine above an idle, maybe 1,500 RPM/s so coolant is circulating throughout the engine and radiator. IF the coolant level in the radiator drops significantly below the top row of tubes add just a bit to bring it back close to covering those---engine still at high idle. Replace the cap, ease the throttle off and leave idling for a while, inspecting for leaks, watching temp gauge and feeling the air stream.

Following the above you'll have flushed your system sufficiently to renew the coolant and remove enough of the old to be very effective.

I've used this same approach for many a year now, all on motors before Ford's modular motors became standard. It's worked very well for me.

 

Absolutely correct bud. There's a vac operated valve in front of the heater core, so ya gotta have it open.
I got er done, but still running a little warmer than id like.
We're talking around the "A" on the temp gauge slight grades, is that normal? I wanted to also do the thermostat, but sadly I don't have the right tool for the job.

 

I don't really equate my coolant temps to the gauge words---I'd rely on a stem-type thermometer to be really sure what temps I'm running. It's been so long since I owned anything older than a '97 E-Series so can't recall where the temps on the gauge tend to read.

What tool are you missing for the t'stat? IIRC the housing is held to the block with bolts and gasket?

 

Does the 4.2 v6 have a drain plug on the block? That is my preferred method. Where is the drain located?

 

Most blocks I've encountered don't have a drain per se for the coolant. The freeze plugs are mounted a bit too high to really, really completely drain the block and replacing them ain't a walk in the park.

Seriously though there's no real way to drain a block bone dry--the best we can hope for is a through flush which in effect replaces any old coolant with fresh water or new coolant.

Not trying to show my age but the method I outlined has been in practice since the late 50's, long before aluminum blocks and acidic coolant became topics of great interest.

 

Where the thermostat is located- is in an impossible (with my tools) lower bolt to get any leverage on. There's a water pump, a distributor, and a mounting bracket in the way. went to autozone to try to buy an angled wrench, not angled enough..

To top all this off, every single hose I've replaced is now leaking.
Any tips to get them to stop? I tried cleaning the fittings, but you know, tight quarters....

 

I think your method is going to work. Since I will be changing the radiator fluid myself with tighter than factory intervals, it will be better than good enough.

The following is way off topic...I am tired of incompetent work done by national chain installers and workers-I had 2 hub caps dented by an installer at one of the largest tire distributor in the US. Just today, Jiffy Lube wanted to charge extra to flush the tranny in my Subaru because it used older Dextron ATF.

I would rather do most of the routine maintenance like oil changes, tranny flushes, radiator flushes, etc myself because I know that I will do it right.

When I need difficult work done, I will find and independent shop that employees real mechanics. $120 per hour for a good mechanic is cheaper than replacing a transmission or engine.

 

Does anybody have a trick to getting to them bolts?

 

If you have some images of your work area and the leaking hoses etc we might be able to help.