Oil Cooler Hose Replacement

[JimBee]

I've read the main and daughter threads. Details and photos do an excellent job of documenting the process. But, apart from the opportunity to clean up the oil t-state, i still don't get why the t-stat has to come off its engine mount. Why not just remove the pipe bracket, remove the radiator connections, then pull the hose connections from the t-stat? Clean things up, arrange new or renewed hoses, o-rings etc., reverse the process. Done. No?

[jreed]

JimBee-- That's a great question. I'm glad you asked! I wanted to approach the job in just the way you suggest but I found that there was no easy way to get a T30 bit into the screw hold that holds the oil line clamp in place without first removing the oil thermostat from the car. In my case the frame of the car interfered with getting a tool into the right position to undo the screw. There might be a way to replace the lines without removing the oil thermostat, but I found that removing the thermostat was the easiest way for me at the time.
This picture shows tightening up the clamp to hold the new lines in the thermostat. I found the only way to get my ratchet and bit into position to turn the T30 was to remove the thermostat.

VolvoOilCoolerLines32.jpg (115.46 KiB) Viewed 1122 times

[abscate]

So I've gone through all of the posts on this and I have a slight twist as far as issues go. I'm also leaking radiator fluid from the top oil cooler line, where it attaches to the radiator. Does this mean I need a new radiator? Its a very small bubbling weep...best way to describe it. Just noticed it the other day as it finally gave me a low coolant warning. So its not loosing a lot. Is there an easy repair, or is this a complete radiator replacement?

Side note this is after having a new A/C condensor put in at a shop in NC. Then I drove across the country, moved to CA. Just noticing the coolant leak now that the car is in a garage.

Thanks in advance guys.

If you can get it dry, it might plug from the outside with some epoxy. I would not recommend any STOPLEAK product that you add to the coolant to try and fix from inside.

[JimBee]

I haven't looked at mine closely with intent to replace the line, so I apologize for idly speculating, but is there no way to use a swivel joint to get in there? Shall we assume dealership techs take the whole assembly apart to replace the hoses?

[holler1]

I've read the main and daughter threads. Details and photos do an excellent job of documenting the process. But, apart from the opportunity to clean up the oil t-state, i still don't get why the t-stat has to come off its engine mount. Why not just remove the pipe bracket, remove the radiator connections, then pull the hose connections from the t-stat? Clean things up, arrange new or renewed hoses, o-rings etc., reverse the process. Done. No?

The above is what I did at first when I replaced the lines. The problem I ran into was that I damaged one of the O rings that go on the pipes at the thermostat. I didn't realize it at the time but found a leak a day or two later. I had to re-do the job with new O rings and found I couldn't get the O rings into the thermostat that way without damaging them. It's very easy to cut or pinch them - do this very gently. I would advise against using the screw and small thermostat bracket to push them in unless you do it very carefully. I removed the thermostat and was able to get much better access to insert the lines and O rings with the thermostat off the car. I installed the lines in the thermostat and then pushed the whole assembly into the right position before re-installing the oil line center bracket and thermostat. That wasn't very difficult - just try to remember how the flexible lines go before removing them. Removing and re-installing the thermostat itself isn't difficult. I found the hardest part was getting the oil line bracket bolt back on, the one that holds the lines to the engine at the middle of the lines. I had to use a very long 1/4 inch socket extension to get at the bolt.

Regarding the leak at the radiator - I wonder if the leak might be at the oil line connector. If so, replacing the line and O rings might fix it.

[JimBee]

Okay, thanks holler1. I get it. The o-rings are very delicate and you're working with two pieces that have awkward sharp edges, probably without the best viewing angle. I was thinking that dealing with the rectangular seal was tricky enough to avoid if possible. From your explanation that doesn't seem so bad—IF the two T-40's come out nicely.

[jreed]

Agreed! I have heard that the T40's on the oil thermostat will strip out if not loosened carefully. One poster (I can't remember who) suggested cleaning out the tops of the screw heads and making sure that the T40 bit sits deep and square before applying torque.

[holler1]

Okay, thanks holler1. I get it. The o-rings are very delicate and you're working with two pieces that have awkward sharp edges, probably without the best viewing angle. I was thinking that dealing with the rectangular seal was tricky enough to avoid if possible. From your explanation that doesn't seem so bad—IF the two T-40's come out nicely.

I agree with Jreed's caution about the T-40s. I always worry about stripping these kinds of Torx bolts, but have had pretty good luck with them. I didn't have any trouble with the rectangular seal. In my 98 V70 AWD the inside of the thermostat was clean and the rectangular seal was intact and didn't show any wear. When I first saw it, I thought I would have trouble with it, but didn't. In addition to the problems with O rings at the thermostat end, I somehow bent up the bracket that holds the line onto the thermostat and had to beat it flat. However, the most frustrating item for me was the hex bolt and bracket holding the lines to the engine - I wish I could say I knew the secret to getting that back on, but I just recall a lot of time spent trying to get the bolt started. Someone else had a post I found later that had a tip for that, but I don't remember it.
I'm attaching a link to some pictures I took at the time in case any are helpful. https://picasaweb.google.com/1133845974 ... oolerLines#

[erikv11]

I started to strip out one of the T40 heads by trying to get in there quickly without getting anything out of the way (I think I had to raise the engine a bit for better access, don't recall). And FWIW I've done this several times now and I always take off the thermostat at the block, it's easier that way. Just put a little grease on the square gasket to hold it in place at reinstall.