Replacing Oil Cooler lines

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Replacing Oil Cooler lines

Post by warpc0il » Wed May 13, 2020 6:50 pm

The content below was originally posted in this group buy thread, as it related to fitting the lines purchased in that deal.

However, it applies equally to removing and replacing the lines from any source, and so is repeated here for reference.

I would normally say
this_thread_is_worthless_without_pics.gif (11.77 KiB) Viewed 74 times
but there is a video being created, to which I will add the link when available, plus some still frames may also help.

In the meantime, enjoy...
Hopkins wrote:
Wed May 13, 2020 2:10 am
Right! It's going to be a while before I manage to edit the 25 hours of footage into anything vaguely presentable, so here's a write up which may be useful to anyone planning to attempt this work. I'll begin with a kit list, repeating everything mentioned already so it's all in one place:

The custom made oil lines!
Trolley jack and a flat surface to place it on (i.e. not a gravel drive... Concrete slabs on top can cure that
Ramps or a second jack (unless you know you can get one jack under the car on a smooth surface)
Axel stands and wheel chocks
Socket set up to 30mm (10, 20, 23, 24 essential)
Socket extender (at least 30cm)
Flexible socket extender (I don't think that a single universal joint will be sufficient - the rear upper air manifold bolts are really awkward!)
Open spanner set (10, 27 essential)
Perhaps a breaker bar for undoing wheel nuts
Torque wrench for doing up wheel nuts
Spare plastic trim fasteners (eBay)
19mm stainless steel p-clips (2 packs of six,
M6 allen bolts, M6 nuts (I went with nylon locking nuts) and M6 washers (
Comma Hyper Clean degreaser (this didn't arrive in time, and so I did not do much cleaning!) (
Lamp or head torch

Note: the 27mm open spanner is for the two engine-side connections of the new hoses. The four cooler-side connections can be tightened with a 24mm socket, but the engine-side connectors require an open spanner and there is very little room - I had no luck with the various adjustable spanners which I tried and I ended up, luckily, finding a local friend who could lend me a 27mm open spanner.

To put my level of experience into context, I had never done anything to a car before getting the '8 just over three years ago. I immediately learned how to perform oil and filter changes, but nothing more. Last year, with the generous help of Ian Mothersole, we installed the PZ springs and shocks, which gave me a taste of something a little more advanced. I decided that now would be the time to attempt something a little more advanced, but I hadn't realised quite what I was letting myself in for... As per the recommendations here, I followed the Racing Beat instructions ( ... -COLOR.pdf), but the process was punctuated by visits to YouTube for advice.

Firstly, jacking the car up is something that I had never done myself before! I spent plenty of time ensuring that I knew where the hard-points were and I borrowed two (luckily) jacks for the job. I couldn't get a jack underneath the front of the car, so I had to jack up at the side, then insert the other jack at the front, then remove the side jack and insert the axle stands. However, I learned some valuable lessons... Trolley jacks need to move freely during jacking since the arm moves upwards in an arc. Unfortunately, the gravel drive on which I was working prevented this movement and, despite me attempting to take care, before realised quite what was happening, the jack slipped off the front of the front-centre hard point and the car dropped about 20cm before catching on something (the steering rack, I now believe) and wedging horribly over the undertray. I rescued using the side jack and pulling out the other jack which slightly damaged the undertray and destroyed a load of plastic clips. Luckily, no other damage was caused... In future, I will use some spare concrete paving slabs to rest on - this worked for lowering the car. After 90 minutes I had the car up... Luckily, I had remembered to loosen the wheel nuts first!

Battery, battery box and air box removal all went smoothly, although - as I would discover with this whole process - locating all fastenings and connectors for the first time can be time consuming. In addition, having never done this before, each electrical connector was a puzzle and, when it came to rubber hoses, I found it rather stressful applying the force required to remove them. Was this 12-year old rubber simply going to tear? Luckily, I would eventually learn that these pipes appear to be built to last and to be pretty bloody hardy.

The next instruction is where I began to loose heart: remove the "upper air intake manifold". Oh... So, that's, erm, the whole top of the engine with something like 15 different connections?! I found this video very useful: It was at this point that the scale of this task became apparent, and the soundtrack to the video footage that I was taking initially went a little quiet, and subsequently took on a distinctly blue tone... From this point until the end of the disassembly (the end of the first day, approximately 10 hours), I was motivated in equal parts by the fact that the car would, in any case, have to be taken away on a recovery vehicle since it was losing half a litre of oil every few miles, and by the emotionally jarring sense of failure which giving up at this point would have left. With a degree of abandonment, I cursed my way through what felt like a bewildering array of disconnections and awkward bolt loosening.

(It is worth mentioning that, in the video link above, the guy makes a handy suggestion to block the coolant line with something to prevent coolant from spilling everywhere. I didn't have anything convenient to hand and I was too agitated to care, so I ended up with coolant spilling everywhere. I wish I had taken his advice, although I am not yet aware of any negative consequences of my laziness.)

Eventually, I got it off, but I couldn't relax since I was entirely doubtful that I could put it back together again. The last things I removed were the coils which give access to the AC pump. The AC pump is the final part that the RB instructions advise to remove, but I had read PaulAV's comment that he had cut the AC pipe around it instead. At this stage, I was willing to take any possible shortcut to avoid further disassembly, and so I reached for the hacksaw... If I had to do this again, I would certainly look into what removing the AC pump entails, because it took a lot of effort and some seriously awkward hacksawing underneath the car. There is a hard section of pipe which passes between the engine and the AC pump in an S shape, and so you have to find a way to cut the pipe very close to the entrance and exit points. Still, if removing the AC pump entails de-pressurising and regassing the AC system, perhaps this was a shortcut worth taking.

The hacksaw also came in very handy removing the rest of the original oil cooler lines. I found it rather awkward to get them out through the wheel arches. Be careful when wiggling things around - I inflicted a slight bit of damage to the plastic frame of the cooling fans by attempting to force the pipes at some point.

At the conclusion of day one, approximately 10 hours after I begin, I had concluded the removal of the old lines. Completing the disassembly boosted my sprints, despite my reassembly apprehension.

The next day, I was able to begin the significantly more enjoyable process of installing the new pipes. The following video from Essex Rotary is an excellent point of reference: Apparently, the direction of flow through the coolers is important, so it is worth getting the order of connections in your head. As previously mentioned, 24mm bolts are used at the four connections to the oil coolers, and 27mm built-in nuts connect to the engine inlet and outlet. You will need an open spanner for the 27mm nuts. Then I used all 10 of the p-clips I bought, along with bits of salvaged brackets from the old lines (hacksaw to the rescue again, plus a drill), to route and secure the new hoses. In a couple of places I used a pair of back-to-back p-clips to secure two hoses to one another. I also used a couple of holes on a cross member to secure the salvaged brackets. (Subsequently, I discovered that these holes were the points into which the battery box and air box bolts screw, and so now the levels are slightly messed up and engine cover sits a little wonky... I may attempt to rectify this in the future!) I rather enjoyed attempting to make a neat installation of the new hoses, which was extremely cathartic given the stresses of the previous day.

And now, on with the reassembly! Coils first. I double checked the order (left to right, L1, T1, L2, T2) and hooked them all up. Air intake manifold... Okay, this was bloody fiddly, but I began by studying all of the inputs so that I felt I knew what needed to be reconnected. Be sure to check that all gaskets which seal the plastic manifold to the metal engine block are in place; you should be able to see a protruding pink nipple from each. One of mine had been slightly dislodged in the disassembly, so worth checking. I smeared each of them with some oil to help the seal - this seemed like a good idea... A couple of hours later, it was nearly all hooked up. By this point I was feeling energised! However, one last connection... The coolant outlet, I think... Where was it? Oh no! It was wedged on the other side of the manifold, there was no way to feed it through... It all had to come off again! Well, this was at the end of day two, so it seemed like a good time to stop.

The next morning I got straight to work removing the upper air intake manifold again. With my new-found confidence and experience I set to work cheerily, and in an hour I had everything reconnected. Except... Er... I had checked for that wide electrical connector on the throttle body... Oh, no! That lead is for the mass airflow sensor. The one for the throttle body is *behind the god damn manifold*! Aaargh! Well, this time it only took me 30 minutes to remove it all again, retrieve the electrical lead and reinstall. My advice is, therefore: locate and loosely position all leads before beginning the reinstallation of the upper air intake manifold!

From this point forward, it was relatively simple to get the air box, battery box and battery installed again (and to notice that I had not chosen the best places to locate my makeshift brackets).

Time to test! Firstly, fully depress the accelerator (to inhibit the fuel supply) and turn over for 15 seconds or so. Repeat after a pause of 10-15 minutes. Gah! The battery has died! (Some time before Christmas I had left my lights on and fully drained the battery. The RAC guy said that the battery was dead and I needed a new one, which surprised me since the battery was new when I bought the car, so only three years old at the time. However, he did not have a suitable replacement, so I had a chance to give it a run, get home and test it the next day. No problems since, but I wonder if it had never fully recharged?) A neighbour leant me a mains charger which claimed it could refresh completely drained batteries. Indeed, the charging voltage was 12v and the current low - 3.8A, I think - and so it would take about 15h for a full charge. So, I stopped after my morning's work and waited for the next day.

Day four: battery charged! I installed the battery although, in a daft demonstration of laziness, I attempted to secure the positive terminal connection not with a small ring spanner, but with a 1/2" ratchet spanner with a 30cm extension on. What a tool. (Me, that is.) Having already connected the negative terminal, I briefly touched the top of the secondary air injector valve with the ratchet spanner... Sparks flew in the impressive manner characteristic of high current short circuits, and I noticed that a small hole had been melted through the metal top of the valve. Tits. For the time I wrapped it in insulating tape but, since then, folks on this forum have assured me that this is a relatively minor component which just helps the cat for 30 seconds after a cold start. Anyway! The battery performed perfectly well, and in a short while I was comforted by the gentle whir of a happy idle.

Checking for leaks. Nothing apparent! Time to get the wheel arch trim installed, the under tray re-clipped and the wheels on. (Although, I have to admit, I couldn't get half as many plastic trim clips in place as I wanted to. Bloody things...) By lunch time... OMG!!!!111 I've fixed the car!!!111 w00t!

Excuse me. An immediate top up of about 500ml oil was required and, after a drive of about 5 miles, another 500ml. I've kept an eye on the area under the car for the past few of weeks and I've since put on a good couple of hundred miles. It feels wonderful, even though it's simply "not broken" rather than "enhanced".

Retrospective: I feel as though this has been a bit of a rite of passage. I rarely think "I've bitten off more than I can chew", but I really did feel like that, initially. I am a not afraid to tackle household repairs, and I frequently disassemble and fix consumer goods (admittedly, clean, delicate electronic things, rather than hulking, oily mechanical things, but still). I am also a very relaxed person, and I have a good *theoretical* knowledge of the mechanical aspects of motor vehicles. But, during that first day, I became distinctly distressed as I realised just how unaware I was of the detail of the systems and of my unfamiliarity with *physicality* of the components of an engine. However, I can safely say that this has been repaid by an immense sense of accomplishment which I haven't really felt for years.

I now have 25 hours of video footage which I will attempt to whittle down to a comprehensible overview of this process. Video editing is another skill which I will have to develop on the fly, so it will take me a while. In the meantime, I hope you have enjoyed this recounting of my experience!
=D> =D> =D>
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Re: Replacing Oil Cooler lines

Post by mrspiller » Wed May 13, 2020 9:49 pm

Thats a good write up
Fair play to you

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