I have a 1998 F250 (5.4L) pickup and I would like to flush the coolant system. I understand there is a drain plug (or two) on the engine block near the oil pan. Can these coolant drain plugs be removed along with the radiator plug to get all the old fluid out of the system. I read one post that said don't mess with the engine block plugs because they might be rusted and two tough to get off. Does anyone have a quick snapshot of what these drain plugs look like? I also wanted to stay away from buying a coolant flush kit or messing with any of the hoses. Any help is appreciated.

Thanks.

 

if you want to spend the money, go to the a dealer and have it flushed. we have the same machine at our shop (independent garage) and all they do is diconnect the hose and hook up the machine, then turn it on and new fluid goes in and pushes the old stuff out. its good because it gets everything out.
or if you want to do it yourself, you could disconnect one of the hoses and use a hose and flush it out that way, thats what we did with my old jeep

 

As old as it is it is due for new hoses and T-stat anyway. The plugs are simple hex head plugs from what I remember seeing. Personally I pull the top hose and put the garden hose in and let it run. I then fill it with just water and run the truck with that for a few days then flush again and refill with mix. Obviously I don't do this outside of July/August though.

 

This is good advice. I will consider the shop service, but I'd really like to get in the habbit of doing more of the maintanence myself. I just can't afford the dealer/shop rates anymore. I will keep looking and learning. Thanks again for the help.

Cheers.

 

Since you want to do it yourself (which is great) here is how.

2 options. Remove block plugs or not- I wouldnt bother. On the 4.2 there is 1 block plug and its just a square plug that you would get off with any old wrench. I havent taken m ine out yet, its easiest to see them from the underside, they are by the white frost plugs.

So since we are going to skip pulling block plugs, get the truck up to full operating temp. drive it, let it idle, whatever, we need that Tstat to open up. Then when shes nice and warm (shut the truck off) get your drain pan and open up the radiator petcock. 90% of the coolant will come out this way. another option is to disconnect the lower radiator hose from the radiator and draining from there. Then when you are satisfied with the drainage, put the petcock back on, or put the hose and clamp back on, look at how much has drained (should be about 2-3 gallons) and go 50/50 mix your new coolant. I would stick with the same type of coolant, if it had green, use green again, if it had orange, use orange again. I'm guessing your truck doesnt have a radiator cap, its only got a pressure cap on the reservoir- so remove the cap and pour in your mix, when the reservoir is about half full, start the truck. You are gonna need to get it hot again. keep it running and slowly pour coolant in as needed. This part shouldnt take more than 10 minutes. Put the cap back on, use the garden hose ( if its warm) to hose off any mess. and you are good to go.

by the way you can also take out the t-stat, but its really not worth the trouble unless you are going to replace it.

 

Thats my kind of job...I have a follow-up question. When I look through the owners manual at the coolant capacity it states 19 quarts. If my math is correct, that equates to over 4 gallons almost 5. When I drained the coolant before changing the heater core, I estimate that we got about 2-3 gallons. That is why I was considering te removal of the engine block plug. I will check it out tomorrow and decide what to do. Thanks again for all the great feedback.

Cheers.

 

I would go with removing a hose and using a garden hose to flush the system out. If you remove any block plugs, have a wrench or socket, or allen wrench that fits tightly. The engine probably has plugs on both sides of the block. The plugs will be tight, get a wrench that fits tightly, or the head will just get rounded off. An adjustable wrench is not the tool to use here. My Aerostar's owners manual actually had a section on flushing the cooling system. look in your owners manual, maybe you have instructions there. The capicity is starting with a dry cooling system, you will not get all the old water out unless you pull the motor out of the truck, and turn it every way to get all the water out of the water jackets. Flush the system with water, seal it back up, put 10 quarts of pure coolant in, and top it off with water. Check your water level each time you drive the vehicle for a while until you are sure you are not leaking water, and have all the air out of the cooling system.

 

Pulling the block drain on the driver's side is easy, however the passenger side is behind the starter. I used distilled water to flush, not tap. Drain, refill, run until hot. Repeat 3-4 times. Then fill with 50/50 antifreeze/distilled water.

 

I think I got it...Thanks everyone for the advice. This sounds like a pretty easy task and worth while. I hope everyone had a good Christmas and I'm sure I'll have more questions in the future. Until next time...

Cheers.