cooling system question

[wayneh]

Quick question on the 56 PW I picked up three weeks ago.

The previous owner said it ran hot. I have only driven it a few miles, but when I checked the radiator temperature and head temp with my IR probe it was not above 160. Possibly the gauge is bad.

Today I went to install a new thermostat since the owner did not. When I drained the coolant, I got about 1.5 gallons out at the most, but the manual says the cooling system is 17 quarts. I realize the engine will hold some of the water, but shouldn't the radiator hold a lot more? He said he recored it, and the outside at least looks good, but what the hey?

Thanks

Wayne
Wayne@flymha.com
Davidsonville, MD

[Gordon Maney]

See if you have a drain plug in the block you can remove. If you do, observe which end of the engine the plug is on, and jack the truck up at one end to further lower that drain point. Even then, you will not be able to get all water out of the cylinder block.

[Tom Petroff]

Was thinking the same thing Gordon, only I would be interested in seeing how much if any sediment might be there.
That may prove to be a clue,I would think.
TGP

[wayneh]

I will check the drain on the block, thank you.

I have a friend who is a few years older than I am, and his business is Annapolis Radiator and Body Shop. Well, in this day and age they don't do radiators, but he made some good suggestions that make a lot of sense.

First, he said to take the hoses off the radiator, and block the lower outlet. Then, fill the radiator to the top, and remove the cap on the lower part, and see how much water comes out, and see how fast it comes out. That will tell me if the radiator is all plugged up, and that makes a lot of sense.

Then, he said do the same with the engine. Block where the lower hose is, fill the engine with water from the top, and then let lose and see how much comes out, what it looks like, and how fast it comes out.

Wish I had time to look at that tonight, and I guess tomorrow would be bad timing since it is the 14th...

Soemhow I ought to see close to 17 quarts coming out, minus what is left in the block. I just checked how much total fluid drained out, and it was less than six quarts, which is about ten short....

Wayne

[gmharris]

Just finished cleaning my radiator. I stuck a garden hose with good volume in the top of the radiator. The water flowed out the bottom as fast as it went in.

Be careful about putting a hose in the radiator. The tubes beneath the fill neck are delicate and can be bent closed by a hose nozzle, maybe even by too much water pressure.

It's also a good time to turn the radiator upside down and flush the radiator out the other way. A lot of junk came out of my radiator.

[wayneh]

GMHarris:

Thanks. That is my weekend project. I did look at the canned radiator flush, and I just don't think that will do much. but I am sure it is safe for the envireonment.

If you don't mind, how much water does your radiator hold? The system holds 17 quarts according to the book, and I only got 6 out of mine....

If that does not work it is on the way to a commercial shop who will clean it. It is a bit of a shame, the previous owner did re-rod it, but looking down into the top they are plugged.

I'll also look into getting a coolant filter. That stuff comes frome someplace.

Thanks

Wayne

[gmharris]

Before you take the radiator to a radiator shop, try the flow test with a hose. If the radiator can pass the flow of a garden hose without restriction, then a radiator shop cannot help you much, especially since the radiator may have been already been re-cored or rodded out.

The model radiator I have has a crimp-on style top tank. The radiator guy was hesitant to rod-out the radiator. He said the crimp-on style tanks are often damaged when the crimp is removed.

Looking into the radiator opening will only tell you so much as visibility is limited to just a few tubes. And, as I pointed out, those tubes are often damaged by people putting hose nozzles into the radiator.

Even if the radiator is plugged, try cleaning it with a 50/50 solution of water and muriatic (pool) acid. Look on the web for the procedure and safety precautions.

The acid is not terribly dangerous, but take the safety precautions (especially for your eyes) that you find on the web. You might have to do the flush several times. You need to flush the radiator well and neutralize the acid with baking soda. Muriatic acid works much better than standard radiator cleaner. I also flushed the engine on my truck with muriatic acid/water and could see a big improvement inside the block. Remember to take out the block drain (pipe) plug to thoroughly clean and flush the engine.

The heating problem your truck is having may also be caused by a blocked water distribution tube. Check the web for information on the tube.

I'm not sure how much water the radiator holds, but it is not as much as you might think based on the size of the radiator. The tubes, which do most of the cooling, are pretty small.

Like I said, check the flow first to get an idea of the condition of the radiator.

[wayneh]

GMHarris:

That is great advice, thank you. I have some muriotic acid at home already, so I'll try that. I previous owner said he had a cooling problem, and when I drained the coolant to check out the thermostat I realized something was funny with the total capacity of the cooling system.

The previous owner said he replaced the cooling distribution tube, so I am hoping that is ok.

thanks again for your advice I'll let you know how it works.

Wayne

[gmharris]

Sometimes, we miss the obvious when trouble shooting a problem. I had an old Buick that used to overheat when driven hard. I tried just about everything. Then, I realized the belt was slipping. Make sure the belt is in good condition and reasonably tight. Try a little sand paper on the pulley grooves if they are shiny.

If you take off the water pump, which I recommend, check the water distribution tube by pushing a welding rod, or something similar, back through it. The wire should go back almost all the way the length of the block.

The water distribution tube has just some small slots at the top. On my engine, the tube looked good, but was clogged with rust chips about 1/4 of the way from the back.

If the previous owner replaced the tube, but didn't do a good job of cleaning the cooling system, the tube can easily clog.

If the distribution tube was recently replaced, it will probably come out fairly easy if you really want to check it and see the condition inside the block. Otherwise, just pulling the water pump will allow you to see around the first cylinder.

[wayneh]

GMHarris:

Well, when I first got this home, I though the cooling problem might be an easy fix... The belt was LOOSE! And not just slightly, I could turn it easily in my hand with minimal effort.

Next was to drain the coolant and check the T-stat. The lack of water that came out tells me something else is going on.

The previous owner did say he put a new cooling tube in, and re-cored the radiator. I have no reason to doubt him. I was not planning on pulling the water pump to look at that tube, but if the radiator is plugged up, it goes to reason that that tube is plugged....

Thanks for the advice, I'll keep you posted.

Wayne

[gmharris]

Yep, I know how it goes.

I started to add anti-freeze. Then I decided the radiator needed flushing. Why waste anti-freeze in a dirty radiator? Then I wanted to flush the block too. So, I removed the radiator. Since I had the radiator off, I might as well install the new water pump I had. While the pump was off, I decided I should pull the water distribution tube to check it. It needed replacing. Then I saw a leaking front seal. So I pulled the timing cover. Thought since I had the cover off, I should check the chain. Then, the front pulley needed a sleeve. Then I thought I should do some cleaning and painting. Since I already had the radiator off, I decided to pull the fenders so I could get to the rest of the engine and repair some wiring. Since I had the fenders off, I thought I should set the valves.

So far, I've resisted pulling the manifolds off to replace the heat riser valve and the head to check carbon buildup.

This is most difficult job of adding anti-freeze I have ever done.

[gmharris]

In response to your email question:

I can't exactly tell you the steps to get out the radiator. My FFPW didn't have a radiator shroud or winch and some of the bolts were missing. That made the job easier for me and, after loosening a few bolts and taking off the hoses, the radiator pretty much slid straight up without problem.

You have to remove the radiator cowl and you may have to remove the fan or the shroud before lifting out the radiator. Not a bad job as far as things go. The side panels can stay in place.

There are people here who have done the job many times and maybe they can add something.

[wayneh]

"You have to remove the radiator cowl " tells me what the book does not. Although, it appears that cowl is held on with 4 bolts that are under the cowl if I am seeing it right. My first instinct was to remove the cowl, but that didn't look as easy as I thought it would be!

thanks

Wayne

[gmharris]

OK, here's a quote from the dodgepowerwagon.com site: "You need to remove the shell, grill and radiator as one unit first, then pull the radiator out of that. It is a pretty easy job, takes me about 30 minutes. Remove the front fender bracket bolts and the big nuts at the bottom of the radiator frame."

My job was easier because someone had "kindly' removed the piece of sheet metal that closes off the the space between the radiator and cowl. I was able to just reach in and remove the four bolts securing the cowl allowing me to lift out the radiator.

Both PW's I removed the cowl from were this way. Obviously, your PW does not have this "modification".

If you go to Phil's archives on the dodgepowerwagon.com site you can do a search for info on radiator removal.

[wayneh]

thanks GM. I did not see that on the other forum, but that will work. I may not need to pull the winch off then, which would be nice!

Wayne