PHH

[Wayne]

When doing the PHH replacement, is silicon high temp hose recommended, and what size hose is needed?

[Gumby]

5/8 silicone slips right on. It's spendy, but you will have a lot left over from a foot. Others extoll the virtues of Gats green stripe, but it's very still and hard to bend into place.

[IdahoDoug]

I used the silicone. Did not use the heat shrink clamps they recommend as replacing these later is a nightmare due to restricted space (you need to cut them off!). I'm using the spring clamps that came on several heater hoses from the factory, but had a slight leak I attributed to one clamp not being fully on the silicone hose (green, from NAPA). I'll know if this was the case when I check for leaks in a few weeks.

Doug

[cruiserdan]

I prefer the green Silicone cop car stuff, with lined stainless steel worm drive clamps. The stock spec for the length is 50 mm.


D-

[Rich]

If you are really really particular then with silicone hose you will use lined stainless steel worm drive clamps that incorporate a constant tension spring. The spring compensates for the fact that silcone hoses don't bond to the metal pipe the same way that rubber hoses do. The spring helps prevent cold leaks. This is according to web research I did in the past.

I used Gates Green Stripe hose to do the job. In my personal experience of doing the job once, in order for Gates Green Stripe to be a practical choice you should be prepared to fully remove and reinstall the metal coolant pipe that runs from the top of the block down to the PHH. Doing this requires patience, agility, patience, long arms, and patience. If you are in short supply of any of the above, I believe silicone hose is the better choice as I understand it can be more easily installed without removing the pipe.

Rich

[Riley]

Oh boy, now I need a course in heater hose materials. They didn't cover this in shop class.

So what color is the "good silicone" hose that I can use without pulling off the pipe?

I hope it's not green or I'll be getting confused with Gates green hose. :-\

I thought changing the hose would be tough enough but now getting the parts is going to take a PHD.

[IdahoDoug]

Riley,

Tragically, the NAPA silicone hose is indeed green. To help you keep them straight, the Gates Green Stripe has a green stripe, and the green silicone is - well, green.....

Doug

[anderaa13]

If you use silicone, use some type of clamp that keeps constant tension as rich mentioned. I didn't, and have had problems with cold coolant leaks using napa green silicone and regular lined clamps.
aaron

[Riley]

Regarding the >> lined and constant tension spring clamps <<

Simon has spent the morning trying to find the above clamp in Western Canada with no luck. He can only find the lined clamps.

We trust that not having the tensioner spring is ok perhaps not considering other previous posts. Maybe we need to continue with more research and get our PHDs before proceeding.

For the record the clamp part number we found is: Tridon ET-10
We think the correct size is 27mm.

This is a lined clamp but has no constant tensioner spring.

I hate to think how much $$ in time and energy was spent trying to find these clamps and the "green" silicon hose (not the Gates green stripe stuff). PHDs don't come cheap.

Living in Canada is like living in a 3rd world country when it comes to finding specialized parts.

[cruiserdan]

Well,......the beer's not bad and the hunting's really good

[Rich]

[quote author=Riley link=board=2;threadid=7219;start=msg60323#msg60323 date=1068235790]
Regarding the >> lined and constant tension spring clamps <<

Simon has spent the morning trying to find the above clamp in Western Canada with no luck. He can only find the lined clamps.

[/quote]

Look at catalog page 206 at http://www.mcmaster.com/ for an example.

Rich

[Riley]

Very cool site. Thanks Rich!

You should take the role of head non-OEM purchasing agent for the 80's forum.
Dan's already got the OEM job.

R

edit - in the new version of the catalog it's on page 211

[Wayne]

I really appreciate the tech help on this job.........

Wayne S

[landandsea]

My boat diesel mechanic told me he no longer uses silicone hoses. He said they often drip when cold. You might not notice the small amount of initial seepage on a vehicle, but it accumulates under the engine in a boat. Also, there's many more connections to leak on a boat engine - with all the coolers and heat exchangers.

Don't mean to rain (or leak) on anyone's silicone PHH parade, just passing on the experience of someone who has to live with the results on a daily basis.

Ed

[cruiserdan]

Ed,

I'm curious. That stuff is all I ever see on cop cars. I have several friends in law enforcement and that does not appear to be an issue for them. I wonder what the difference may be?


D-

PS, you'd think if anything would leak, it'd be a Caprice

[landandsea]

Dan,
Perhaps the difference is that it's not their car. They didn't just spend a bunch of their own money and end up with drips.

The durability of the silicone hoses most likely offsets the mostly imperceptable seepage.

Silicone is bullet-proof, isn't it?

Glad to read you're out of inventory hell

Ed

[Pitbull]

When mine was replaced it would leak an amount the size of a quarter if it set for 2+ days. If it did not set for over 2 days there was no leak. Pressure tested it and could not get it to leak. Finally installed some Barr's and it quit leaking. Barr's is also suppose to be good for my water pump and they use it in all new GM vehicles on the assembly line so I figured what the heck. That was 9 months ago and no leaks or problems.

[landandsea]

[quote author=Pitbull link=board=2;threadid=7219;start=msg60645#msg60645 date=1068314598]
Barr's ...they use it in all new GM vehicles on the assembly line... [/quote]

That could also be interpreted as a lack of confidence in the tolerances of GM parts and in the abilities and training of the assembly workers. ???

Ed

[cruiserdan]

Noooooo, couldn't be

[landandsea]

I'm sure that neither Toyota nor BMW or Porsche use stop-leak as OEM.

Notice, Cdan, the good company I associate Toyota with.

Ed

[Riley]

Hey thanks Rich for the McMaster site.

I've got 4 clamps on order for Simon and I. Getting the hose and clamps has only taken us like 1.5 weeks to deal with.

Jeeze - I'm glad I don't do this for a living. Takes me 2 weeks to get the parts to replace a heater hose. Then another 2 or 3 weeks to research on the web the best way to tackle the job.

[Rich]

Riley,

Your welcome. Let me know anytime you want me to help spend your money.

Rich

[Rich]

I didn't use silicone hose. I used Gates Green Stripe hose and Awab hose clamps. The hose clamps are for hose 15 - 24 mm in diameter. The hose is about an inch in outer diameter, so the clamps are pretty much as small as will fit on the hose. The Awab hose clamps are not constant tension. They are not lined, but instead, the perforations do not penetrate the band, and the edges are rounded. So they do not damage the hose and would be suitable for silcone hose other than the fact that they are not constant tension.

I went with Gates Green Stripe to avoid the two disadvantages of using silicone hose, that is they can be damaged by using incorrect clamps, and they can cold leak. Using the type of clamps you bought should alleviate this two problems. I do believe silicone hose can take higher temps than Gates Green Stripe.

The disadvantage of the Gates Green Stripe is that to be easy to install you need to removed the steel heater pipe from the back of the engine. The hose is very stiff and would be very difficult to install with the steel pipe fastened to the block. If your plan is to leave the steel pipe in place you will find the Silicon hose much easier to install.

If anybody is interested I can post some tips on how to remove and replace the steel heater pipe.

Rich

[Riley]

just to make sure I'm seeing the correct hose.

a) It sits horizontial correct?
b) It sits in the same direction as the axle correct (i.e. sits side to side not front to rear)?

I think I'll leave the pipe on the engine this time.

[Rich]

Riley, I think you have it spotted. See http://www.sleeoffroad.com/technical/tz_heater_hose.htm for pictures.

[IdahoDoug]

The Green Stripe wouldn't be too bad if you use a novel approach that made the rounds a year ago. You only remove ONE bolt holding the tube to the block (upper?) lube the metal pipe and slide the new hose up it until you can fit the other end of the hose onto the block nipple. Then slide the hose onto the nipple, tighten the clamps, and you're done. You did slide the clamps onto the tube also didn't you?.....

This is what I did using green silicone hose and I felt a stiffer hose like the Green Stripe would also be compatible with the approach.



DougM

[Rich]

All I can add is that I think trying to do a slide job with the Gates green stripe would be quit difficult. The hose is very stiff. It is thicker in wall thickness than the Toyota hose and is also a tight fit on the pipes. With enough perseverance and hand strength I expect it could be accomplished. I do recall somebody posting that he installed NAPA's heaviest heater hose that way. I have a long reach, so for me, it was a lot easier to remove the heater pipe entirely in order to replace the little bit of hose.

Rich

[shocker]

~~~~~WARNING: Thread resurrection in progress~~~~~~~

O.K., I replaced my PHH this weekend.

Used silicone hose; the only local supplier I could find was a parts house for semis and other industrial equipment, so you may have to do the same.

Used the constant tention lined hose clamps that Rich mentioned now on page 211 of their online catalog, part #54205K11


Took a little while, I loosened the top bolt of the heater pipe along with disconnecting the hose at the top. I also loosened two of the nuts holding the transmission dipstick/fill tube to give my forearms a little more room.

What actually took longer was flushing the engine coolant afterward: fill with clean water, let run, let engine cool, drain, repeat..... 4 times. Replaced the thermostat and gasket too. (Thanks C-Dan!)

All in all, not too bad. Bruised forarm a little bit and gnashed my knuckles. What hurts more is [embarassing story warning] I think I broke my left pinky toe stubbing it at the grocery store yesterday.
Yes, a grocery store injury.

[Beowulf]

Ryan,

>> ... fill with clean water, let run, let engine cool, drain, repeat..... 4 times. <<

Hopefully the trip to the store was to get distilled water?

-B-

[shocker]

Yeh, I used distilled water every time. Wasn't sure if I needed to, but it's cheap insurance.