I had the upper heater hose running from the firewall to the head on the sedan (88) spring a leak last night. The hose has been replaced, but that hose gave me more trouble doing the R&R than any hose, belt etc. I have repalced to date. The heater core repalcement I did on my '88 wagonwas not as frustrating (the fact that I did the hose R&R in the rain didn't help). Does anyone have a trick or tip for heater hose replacement, I still need to replace the lower heater hose. Thanks in advance.

John

At least it isn't a K-jet car. Getting to the PCV valve and heater hoses is no picknic on a K-jet car. I find it easier just to pull the intake manifold off to do these tasks.

Thanks to all for the suggestions, the info should make this job much easier in future!

I've done that job while on a piece of plywood laid across the fenders. Awkward but not impossible. Recently, while replacing the wiring harness and heater hoses, I found a new shortcut for that lower hose. This is the hose which goes to the metal tube coming back from the water pump.

I disconnected the hose from the water pump and also removed a small bolt holding the tube back alongside of the engine. This freed the tube. I disconnected the heater hose at the firewall. Then with the hose and tube freed, I could pull the hose out from behind the engine and work the hose and tube out from under the exhaust manifold. Lots of wriggling required.

Carefully study the orientation of the hose on the tube, or better yet, take a picture. Remove the old hose and install the new in the same orientation as the old. Tighten the clamp well. Now snake that assembly back under the exhaust manifold and behind the engine. The new hose is flexible and goes in easily. Now connect the hose at the firewall and the tube at the water pump. You should use a new o-ring at the waterpump. I didn't have one and reused the old ring. Still not leaking. Don't forget the small bolt holding the middle of the tube to the block.

This seemed easier to do than the old way trying to work on the hose-tube connection behind the engine.

Jim - is it necessary to drain the system first or do you just lose whatever coolant is in the tube/hose combo? I just switched mine out the other day while repairing a water pump gasket using the method you describe. Unfortunately I got the wrong hose and it is now crimping itself about 50% shut. I would like to replace it for peace of mind but am dreading having to drain the whole system again, wasting all that coolant, not to mention the environmental hazards of spills...

Craig
--
'84 245, 285k and getting newer part by part

I would drain the antifreeze using the block drain and a tube. Drain into a clean pan and the antifreeze can be reused. I transfer the antifreeze into clean gallon milk jugs using a large funnel. Then I either reuse the antifreeze, or if it is old, take the antifeeze to a recycle site.

CORRECTION: In the second paragraph, I meant to say "disconnect the tube from the waterpump". The tube and hose are pulled out together, the new hose put on the tube (using proper orientation), and reinstalled together.

This is a good opportunity to do some important maintenance and make the hoses easier. Remove the throttle cables and throttle body. Remove the dip stick tube and get the air intake hoses out of there and it will be much easier to get at the hoses. You then are able to clean the TB as well as possible. You may need a gasket for the TB but it may be fine. You will also have good access to the breather box and flame trap hoses which could probably use a good cleaning or replacement. You will also need an o-ring for the box. There are a couple of switches you can disconnect and clean/lube/apply contact spray

Cleaning and lubing as you put things back will make things easier in the future

None of these things are hard if you take your time and do a little research on the FAQ. Be especially careful cleaning the TB

Or you could just struggle mightily to get those hoses in with all the obstructions in place

The only tip I have is learned from this BB a few years back. Lay a piece of plywood on top of the engine and lie on it so you can reach down in behind the engine with both hands.

I don't know if flushing the cooling system and replacing the coolant every 2 or 3 years would lengthen the life of the heater hoses, but surely it wouldn't hurt.


In the rain, too. Bummer.

Regards,

Bob

:>)