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740 Heater hose removal question

Billh

Member
Joined
May 6, 2005
Location
SoCal
I'm replacing a broken heater control valve on my '91 745T and thought it would be a good idea to replace the 2 hoses.

I can see the clamp on the engine end of the outlet hose so it looks like it can be reached and the old hose replaced.

I can just barley see the clamp on the engine end of the inlet hose. What parts do I have to remove to gain access to this end of the hose to be able to remove the old hose and install a new one?
 
I remove the intake manifold to get easier access to the hose fittings: one is under the intake manifold toward the rear of the engine, the other is behind the manifold at the rear of the engine.

It's actually pretty easy to remove the intake manifold, so if you're sort of new to Volvo repair don't be intimidated.
 
Normally the clamp's screw is pointing up and you can reach with the screwdriver between the manifold runners.
 
You also don't necessarily have to take all the gubbins off the intake manifold. Just undoing the bolts which hold it on and sliding it back can get you some clearance.
 
Thanks for the replies. I'll take a closer look today and see how little undoing I can get away with.
 
Thanks for the replies. I'll take a closer look today and see how little undoing I can get away with.

Replace the gasket if you do pull the manifold, unless you did it recently - they're pretty cheap and it doesn't hurt.

Also be careful not to drop anything down the intake onto the valves :(
 
Another benefit in removing the intake manifold is that it gives you the opportunity to inspect and repair or replace any of the wiring or other things otherwise normally not accessible.

In particular the PCV system can then be checked and cleaned / replaced as needed, as well as the idle air control valve

Also a good time to replace the rubber O-rings on the injectors.
 
I haven't used a screw driver to turn a worm drive hose clamp in a very long time.

To get the hose off the barb, I currently use Wide Tip Radiator Hose Picks.
:
 
I have never needed to remove the inlet manifold to change a heater hose or oil trap or anything on any late model redblock.

On a k-jet equipped redblock, this is a different story.
 
I have never needed to remove the inlet manifold to change a heater hose or oil trap or anything on any late model redblock.

On a k-jet equipped redblock, this is a different story.

I removed it on a '92 940 Turbo because otherwise it was tight and looked to be a PITA.

Since it is easy to remove the manifold I took the easy route.
 
Just make sure you position the head of the screw at an angle where you can reach it from the top next time.
 
I finally got this project done. Thank you all for the comments and information. In addition to the tools mentioned in the comments I would add a 1/4" drive 13mm flex socket to use on a couple of the lower manifold nuts.

I decided to pull the manifold back with everything attached. If you do this remember there is a bolt attaching the manifold to a support bracket. I disconnected the air intake hose at the throttle body to give the manifold room to move away from the head.

After the manifold was moved away from the head I removed 2 additional item to provide access to a lower nut: the fuel hose to the cold start valve and the hose to the flame trap.

The image "Hose Clamp" shows the clamp this post is about. The images "Old Valve" and "New Valve" show length differences. The old valve is the shorter length. Left & right lines on tape show straight section of new hose. I cut about 1-1/4" off of inlet hose at heater end to provide clearance between hose and AT filler pipe.
 

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