DIY: Replacing heater hose pipe T's *important* (2 Viewers)

[SuperExciteBike]

Noticed the tee closer to the driver side was crusty and leaking. Ordered a pair of OEM tees and replaced both. At 143k, driver side tee crumbled into pieces during removal. The one behind it was not as bad, came out mostly intact, but the plastic was starting to soften. Had a gorilla adjustable work platform to get better access but still wasn't an easy reach. Used a combination of vise grip, needle nose pliers, channel locks, hose picks, and locking clamp. Vise grip and locking clamp were the most useful for sliding away the factory hose clamps.

I like OEM parts when possible but in hindsight, metal tees and worm clamps sound like a better idea. These were kind of a pain to get off and it would be nice not having to ever worry about them again.

 

[tjpeters99]

Having just replaced mine I can tell you that it is a good idea to clamp the hoses off. My fittings crumbled immediately (at 200k miles I am not sure if they had ever been replaced). I clamped the

hoses with needle-nosed vise grips with the rubber tape on t the jaws. I also vacuumed out the hoses just to be sure no bits had fallen in.

 

[MuNaught]

I preventative replaced my heater tees yesterday, extremely easy job, took all of 15 minutes. 2003 at 135k miles. Besides some deformation (plastic tube end slightly flat on one side) they were completely solid and not brittle, no leaks. I suspect these were replaced in the past, as the factory spring band hose clamps had been replaced with stainless worm gear clamps.

I replaced both tees with galvanized. See below for dimensional differences. It definitely required additional tightening on the hoses to seal properly. I also replaced the worm gear clamps with some heavy duty stainless constant torque clamps which have a smooth inner band which won't deform the hose outer wall.

Breeze Constant-Torque Stainless Steel Hose Clamp, Worm-Drive, SAE Size 10, 9/16" to 1-1/16" Diameter Range, 9/16" Band Width (Pack of 10)

 

[97 AZ LC]

It's still kind of amazing to me that people are comforted by the non-plastic material and unconcerned about the poor fit. I've said before some enterprising vendor needs to source the right size metal fitting from a metric country some where. I'd go with metal Ts if they were the right size.

By the way, good work by MuNaught.

 

[MuNaught]

It's still kind of amazing to me that people are comforted by the non-plastic material and unconcerned about the poor fit. I've said before some enterprising vendor needs to source the right size metal fitting from a metric country some where. I'd go with metal Ts if they were the right size.

By the way, good work by MuNaught.

Thanks. There is more than enough compressibility in these hoses to make up for a ~1 mm (-7%) diameter change. I would prefer the robustness of metal provided only the proper clamping mechanisms are used, like the heavy duty stainless ones I put on.

 

[flintknapper]

It's still kind of amazing to me that people are comforted by the non-plastic material and unconcerned about the poor fit. I've said before some enterprising vendor needs to source the right size metal fitting from a metric country some where. I'd go with metal Ts if they were the right size.

By the way, good work by MuNaught.

^^^^^

It's already not a problem. The OP just bought the wrong size Tee's.

Get the 3/4" x 5/8" and it will be a snug fit (even on the original hoses if still serviceable).

I've had no issues at all with mine.

 

[97 AZ LC]

There have been an awful lot of leaks with metal Ts necessitating stronger clamps. An over-tightened clamp on a sloppy fitting takes a toll on the hose. The properly fitting plastic Ts are likely to last 20+ years safely. They don't fail with age, they fail with age and heat cycles, and older vehicles typically don't get driven as much.

 

[MuNaught]

There have been an awful lot of leaks with metal Ts necessitating stronger clamps. An over-tightened clamp on a sloppy fitting takes a toll on the hose. The properly fitting plastic Ts are likely to last 20+ years safely. They don't fail with age, they fail with age and heat cycles, and older vehicles typically don't get driven as much.

A 3/4 x 3/4 x 5/8" ( 19 x 19 x 16 mm) tee has greater differential from factory which is 17.6 x 17.6 x 13.7 mm. Yes, it's larger, so the fit will be tighter, but it will be putting greater deformation on the hose than a ~1mm smaller OD tee with constant torque clamps.

IMO either case is acceptable provided the proper fastening clamps are used. The differences are still within nominal deflection of a heater hose.

 

[BEG]

There have been an awful lot of leaks with metal Ts necessitating stronger clamps. An over-tightened clamp on a sloppy fitting takes a toll on the hose. The properly fitting plastic Ts are likely to last 20+ years safely. They don't fail with age, they fail with age and heat cycles, and older vehicles typically don't get driven as much.

I've not seen any evidence of "an awful lot of leaks" when the correct parts are used:

Four Seasons metal tees
Breeze constant torque clamps
NEW hoses (OEM or Gates formed sections)

That's been a proven combination for me over many thousands of miles of daily driving, offroading and loaded camping trips with zero adjustment required.

Most of the leaks I've seen reported are people using used OEM hoses and/or standard worm clamps. Neither is a good idea.

 

[flintknapper]

A 3/4 x 3/4 x 5/8" ( 19 x 19 x 16 mm) tee has greater differential from factory which is 17.6 x 17.6 x 13.7 mm. Yes, it's larger, so the fit will be tighter, but it will be putting greater deformation on the hose than a ~1mm smaller OD tee with constant torque clamps..

^^^^

Yes, that is the point actually.

When re-using old hoses (still viable but not new) they have 'formed' themselves to the old Tee (I.D. of hose is that of the O.D. of the Tee). They will actually look 'belled' on the ends more often than not. They also have lost all (or most) of their elasticity.

So...rather than try to 'crank down' the rubber to meet the SMALLER fitting, just go with the marginally larger size (which will stretch the hose slightly) and use a regular worm gear clamp. If it were an issue...I would know about it by now. I have no leaks and my hoses are fine...going on in excess of 2 years.

Now I would NOT recommend the 3/4" x 5/8" for NEW hoses as it would simply be too tight....but I have stated that previously in other posts about this subject.

 

[Live to Ski]

Look to defense/aerospace/hose manufactures. They have spent millions on this problem and have it defined/solved (think space shuttle o-rings...tech people/specs understood the fit/temp envelope...).

As pointed out above...new Oem hoses/t's/clamps w proper procedure should put you mind @ ease (though I'm going to use metal...do as I say, not as I do)

 

[whirlybirdbrewing]

Glad I caught them before they left me high and dry. Still not a positive event...

 

[Dilspec]

Great thread, mine are due. I read through a few pages. Does anyone know how much coolant they lost or refilled from changing out the hoses and T's?

Thanks!

 

[OEMGUY0720]

Great thread, mine are due. I read through a few pages. Does anyone know how much coolant they lost or refilled from changing out the hoses and T's?

Thanks!

Not much at all, about half a quart when I did mine.

 

[MuNaught]

Great thread, mine are due. I read through a few pages. Does anyone know how much coolant they lost or refilled from changing out the hoses and T's?

As long as you change them out when fully cold, you should lose next to nothing.

 

[whirlybirdbrewing]

Concur. Minimal loss.

 

[uzj100]

Original T driver side. 276k miles.

1999.

 

[S.CarolinaFZJ80]

Great info here...
Thanks to all the contributors.

I replaced my tee’s today.
The driver side T easily broke on removal, luckily only in two pieces that were firmly contained in the hose.
I opted to remove each T with the 3 hoses still connected out of fear of loosing pieces in the system. Turned out to be a super easy 20 minute job.
Here it is all buttoned up with new Tees after a 15 minute leak check with the heaters on.

 

[hoser]

^^^For some reason, I feel an urge to rotate your clamps into their original position.

 

[S.CarolinaFZJ80]

^^^For some reason, I feel an urge to rotate your clamps into their original position.

I originally did too but had to let it go for ease of future use.
The hoses at 149,000 still looked to be in great shape.
At least the clamps are oriented for a quick and easy hose swap if it ever comes to it.