I just did all hoses, the rear heater has 4 hoses under the passenger seat area. Moderately tight spaces with engine and transmission out. I used 1/2" gates hose from NAPA
Those Firewall Heater Hoses (1 Viewer)
- Thread starter e21pilot
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It does keep coffee warm
Rear heater is nicer than the front heater. I prefer to run the rear heater and only use the front for defrausting.
When I swapped the Cummins you have to remove rear hard pipes off fire wall and I just run a 1/2" gates too
alia176
SILVER Star
At NAPA now and grabbing 90° hose in 1/2 and 5/8 sizes. I'm getting confused on the size I need for heater delete 
the ones under the truck look fine actually. its the ones at the firewall that are original (pin clamps) with old white crusty stuff all over. what hoses did you use up there? looks like i can get a foot of Gates hose and cut to length as they are all straight or only slightly bent
the two short ones to the left of the heater valve look to be 5/8"
the two which connect to the hard pipes connecting to the rear heater unit, behind the head, look to be 1/2"
can you confirm? those behind the head look to be a real chore to replace. engine and tranny in the truck.
so what's this special hose all about? still not sure which OE hose it replaces.
Wow, that tool should be required for any new 80 series owner!
I wasn't sure what the special hose was either.. I assume it's not included in any of the Witsend kits?
In fact, does anyone have a parts list for all the hoses not included in the kits? I thought they were pretty comprehensive although I know the PHH is a separate thing: I ordered 99556-30100 for that.
lp2k
Had a couple of drinks.. saw a couple of things
Gates green stripe? Its tough as it gets. Heavy Duty stuff.
- Thread starter
- #50
Just wanted to post that I ordered the hoses from Mr T (all were still available) but they took a while to get to here so I did the coolant exchange first and made my trip up North and back without any problems (except for a wheel bearing which is another story).
I wanted to pass on a bit of advice about the plastic petcock on the lower left corner of the radiator. While it is visible, it's not easy to get to and turn because of the other tubes that run near it. I found a 23mm, 6-point socket of the shape shown below with a 4", 1/2"-drive extension attached made it very easy to loosen, turn and tighten by hand and in a way that was along its intended axis of rotation which helps avoid breaking the plastic valve. I knew there had to be a good use for a 23mm socket.
I wanted to pass on a bit of advice about the plastic petcock on the lower left corner of the radiator. While it is visible, it's not easy to get to and turn because of the other tubes that run near it. I found a 23mm, 6-point socket of the shape shown below with a 4", 1/2"-drive extension attached made it very easy to loosen, turn and tighten by hand and in a way that was along its intended axis of rotation which helps avoid breaking the plastic valve. I knew there had to be a good use for a 23mm socket.
i couldn't source hoses in time, so i bypassed the rear heater instead (already had the kit in my parts stock). Napa had 5/8" heater bypass caps on the wall in a 2-pack; perfect for the firewall hardlines reusing the spring clamps. no coolant loss or smell from that rear of the engine like i was getting before. the metal tubes look just fine, but clearly one or more of the hoses had a small leak only when pressurized. based on how this winter goes i'll decide whether to plumb the rear heater back in.
i wasn't expecting for a firehose of a stream, shooting straight over the axle, laughing at my drain pan sitting under the radiator
all the hoses? even the "special" one?
yea, i didn't touch the drain on my old radiator. but the new one i was able to easily twist out; it had only been in there a couple weeks before i realized something along the firewall was leaking
i wasn't expecting for a firehose of a stream, shooting straight over the axle, laughing at my drain pan sitting under the radiator
Drain is a joke. It is less messy to take a five gallon bucket and put it under the lower radiator hose and just pull that off....hate the placement of the drain on the 80.
i did the 5 gal bucket and lower rad hose when i replaced the old radiator. i still made a mess. then had trouble seating the hose back to the rad neck and getting a leak free seal w/ the spring clamp. so tried the drain plug this time. now that i know how strong the stream is, i can easily position multiple catch trays and a bucket.
i'd say both have their pro's and con's
I pulled the hose on the engine side and had a trash bag in the bucket and wrapped around the hose when i pulled...i still had some splashes but it was a lot less. I hate doing it either way.
- Thread starter
- #55
Not sure what the "special" one is? I only ordered the hoses at the back of engine on either side of the heater control valve. I didn't order anything that routes to the rear heater now I am curious if I missed a hose!
Re: Draining the radiator, I have to drive to another location where I can work on my rig. This means I am working on a hot motor unfortunately. My solution is to raise the front end about 4" on ramps, remove the cover plate, use the 23mm socket to loosen the petcock enough that the hot water just starts to drain out onto the core support and it comes out about four different spots below which are close enough that I can catch them all with a 5 gallon HD bucket. Then as the streams slow, I start to open the radiator cap a little at a time to keep the flow about the same. It takes about 20 minutes to fully drain this way. I also do the same --slow stream-- approach for the block drain at the same time but use my oblong oil pan to catch that because the coolant tends to drip along a wider section along one side of the block. I catch about 98% of the coolant this way which is good for me because I have to clean up the driveway before I leave!
Re: Draining the radiator, I have to drive to another location where I can work on my rig. This means I am working on a hot motor unfortunately. My solution is to raise the front end about 4" on ramps, remove the cover plate, use the 23mm socket to loosen the petcock enough that the hot water just starts to drain out onto the core support and it comes out about four different spots below which are close enough that I can catch them all with a 5 gallon HD bucket. Then as the streams slow, I start to open the radiator cap a little at a time to keep the flow about the same. It takes about 20 minutes to fully drain this way. I also do the same --slow stream-- approach for the block drain at the same time but use my oblong oil pan to catch that because the coolant tends to drip along a wider section along one side of the block. I catch about 98% of the coolant this way which is good for me because I have to clean up the driveway before I leave!
i believe the special one is a 1/2" hose connecting to the firewall hardlines servicing the rear heater. i'm not sure exactly which one (50/50 shot) but i'm guessing its the one under the heater valve. until i figure out exactly what is what, i'm leaving mine bypassed.
sounds like you have lots of experience draining the system. i'm still learning and pulled the radiator cap first. whoops! but i also don't want to wait 20mins for a slow dribble. i'll just hose down my driveway for any spills when i'm done and hope the EPA doesn't see me.
when i'm in the garage i use a plastic kiddy pool underneath, with a bucket in that.
