Changing out Rad hoses and T-stat

[marjoa]

1) So I've been contemplating changing out our Rad hoses (upper and lower), heater hoses and Motoraid hoses and the T-stat while we're up here in Maine this summer. I have good access to a driveway and a garage. I've done a thorough examination of all the hoses and they all look so darn good. But I do know that hoses go bad and fail from the inside. I do regular coolant flushes which helps hose life, but in the end my hoses are now 7 going on 8 years old. I just don't know if it's all worth it right now and maybe try to get another couple of years out of them. Coach has 25,600miles on it and of course we FT.
What are your thoughts on my hose age thing?

Part of me says just take it to a medium truck service center or my mechanic back in Texas this winter and let them do it. This is a messy job. But on the other hand I'm quite capable, have the room to do it and can do the whole job for about $500 or so. Have it done by a shop it will be twice that or more.

I changed the main belt and flushed all the fluids back in late 2016. I'm due to flush the brakes again this winter.


2) When I was growing up I seem to remember fiddling with the T-stat could cause more problems than they solve. It was one of those "if it works don't fix it" things. Our coach always runs at about 209º-212º according to our Scanguage II. Sometimes a little cooler (like cold winter mornings) but no matter what the conditions—on the freeway—towing or not towing our toad, we run about 63-65mpg we run those temps and it always runs great. Even climbing all throuh the mountains in PA getting up here, same temps. So if I do decide to change out all the hoses now, I might as well change out the T-stat.
- where is the T-stat located
- Is it hard to get out / put it...any other advice here
- What degree T-Stat is it supposed to be installed

Oh...and do you drain the radiator from the bottom with that white nylon nut or is there a better way?

Any other advice on this project is appreciated.

If I do this job, I plan on buying one of these to add the coolant and get all the air out too.

https://www.youtube.com/watch?v=-SfhBRvVbtg

[Skip426]

I'm not sure if your gas engine uses a " vented t'stat " or not .
A vented t'stat would slowly clear any air trapped in the engine , just sitting for a short time during the refill . The air pocket in the heater core is the issue , because it is above the top of the radiator .

Your engine will have block drains , just below the level of the core plugs on each side , that should be removed , to drain coolant and check for sediment build up at the bottom of the water jacket.
When you remove the block drain , if the coolant doesn't flow out , you have a sediment problem that will require a block flush , after you poke through the sediment to get the coolant out.

Catching all the coolant for proper recycling , remember it's toxic.

Info on t'stat temp will be available from your engines manufacturer.
Possible there is only one temp available.
T'stat is under the upper rad hose housing on the engine.

You've done coolant flushes before ... how were you clearing air pockets then??

[arcaguy]

[QUOTE=marjoa;4819136] It was one of those "if it works don't fix it" things. Our coach always runs at about 209º-212º according to our Scanguage II. [QUOTE]


I think this says it all. A 7-8 year old radiator hose and thermostat should be fine. If it's rubber and isn't soft I wouldn't worry about it. If it's silicone I'd worry even less. Personally I'd spend my time catching some trout. Good for the soul and good for dinner too, win/win.

[Waiter21]

Oh...and do you drain the radiator from the bottom with that white nylon nut or is there a better way?

Yes. unscrew it, you can completely remove it if you wish. Also remove the overfill cap to allow it to breath as its draining. It will drain out about 4 gallons. System capacity is about 8 gallons..

If I do this job, I plan on buying one of these to add the coolant and get all the air out too.

Really no need to. One or two heat/cold cycles will blow all the air into the overflow and suck in antifreeze.. just keep the overflow full for the first couple heat/cool cycles.

NOTE - I havn't changed my hoses, they are 20 years old (70k miles) and in very good shape. Maybe next year..

When I re-did my exhaust studs (new antifreeze). I flushed the system several times with plain water to get as much of the old antifreeze out. I removed the thermostat from the housing so water would flow freely, opened the lower drain, and ran the water hose into the overfill. It would pump water in about as fast as it dumped out of the drain. I'd started the engine end let it run for about 15 minutes like this to purge all the old antifreeze out.

IMPORTANT, Don't forget to run the heater on HIGH. Many F53's use a valve tin the heater hose, so setting it to high opens the valve and allows fluid to flow through the heater.

After I was sure it was mostly water in the system, I drained it from the radiator, then re-filled it with 4 gallons of pure antifreeze. Remember, the system capacity is about 8 gallons, so 4 gallons water and 4 gallons of antifreeze gives me a nice 50/50 mix.

[twinboat]

I ran my 2000 MH up to over 50,000 miles with all original hoses and belt. Ford says replace the belt at 90,000 miles.

I thought at 18 years it may be time to start replacing the hoses and things so I traded it in.

I did replace the thermostat at 40,000 miles because it started showing large temperature swings. Easy job on a class C and I found the bypass disk was falling off the thermostat.

[Hooligan]

Prior engine Cummins ISB. --Advise so far is good, I would add-- that last refill after flushing, fill with distilled water, then drain and refill with the full strength antifreeze. About 1/2 the distilled water will not drain and it is the correct water to mix with antifreeze.

[marjoa]

Originally Posted by Waiter21

One or two heat/cold cycles will blow all the air into the overflow and suck in antifreeze.. just keep the overflow full for the first couple heat/cool cycles.

So once you change out all the hoses and refill with new antifreeze, do you do these—One or two heat/cold cycles—right there in the driveway?