RHD Oil cooler upgrade with some pictures

[FMJ]

Ok after waiting for my warranty to run out and planning this for a couple of years I finally took the plunge and did the oil cooler upgrade.

Just to set the tone I am generally pretty good with cars having stripped an Impreza back to the chassis and fully rebuilt it with plenty of customisation/restoration and I own most tools/have performed plenty of work on cars over the past 16 years.

With all that in mind I want to say that this job seems very simple on paper but it has some very awkward parts that require a lot of patience.

You can buy kits but I sourced the parts myself for about £600 You could go cheaper, but I went with Teflon hose, setrab cooler and decent setrab fittings.

Also in the picture is the mocal thermostatic take off plate (the supplied silver colour fittings were removed and swapped for the better lower profile setrab ones). Some aluminium bar to make the brackets for the cooler. A setrab rubber dampened oil cooler bracket set. A samco U bend hose for the coolant lines with two sizes of JCS clamps as I didn’t know which size I would need. Some stainless bolts for the cooler brackets. A length of silicone hose to put over the stainless braid which would stop it rubbing against other things (stainless braid can cut through other materials due to vibration) I didn’t use the blue hose joiners in the end. Also some spare oil.

Firstly use a you tube video to take the front bumper off. You have to remove the radiator top panel/cover, and the engine under tray. I left the wheels on and had the car on ramps. You have to half undo the arch liners so wheels off may have been easier or if you are on stands you could turn the wheels to get more access but I managed like this. The hardest part is the little bumper mount screws (one on each side tucked up behind the arch liner) whoever designed these should be slapped. The best way to get at them was a short flex drive handle.

There is a lot of talk about bumper tabs breaking but certainly on this first time off mine popped off and on without issue. Just make sure you get the screws behind first and pull on the corners evenly as you pop the tabs away from the body work. Also make sure you have undone all the lighting wires and impact sensor wires before you try taking that bumper off. All the wires are easily accessed underneath once the under tray is removed.

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[FMJ]

With the bumper off here is what room you have to work with. Luckily there is a huge gap in front of the aircon rad to fit a cooler.

 

[FMJ]

Now there are several ways and locations you can mount your cooler. I decided to mount mine low and attached it to the bumper support bar. To make drilling the bar easier I removed it from the car. There are 8 bolts holding it on. Be aware four of them have nuts on the back so remove the rear nuts first before undoing the bolts!

 

[FMJ]

While we are looking at the front here are some more reference pictures.

This is where the lower radiator pipe supplies the stock cooler with coolant. You can see the two lines here which connect to a plastic hose section.

The lines run back over the subframe behind the oil filter and along the side of the block to the cooler.

I will mention this now as we have the pictures up. Removing those hoses looks so easy. They even have those easy quick release hose ends! But due to the space you have to work with they were a bitch! I didn’t have enough strength in my fingers to release them due to the angle my hand was at and there wasn’t enough remove to get screw drivers or tools to both sides. Of course the fact they are close together also means the inner tabs are very hard to access. I got pissed off and knowing I wouldn’t use the stock cooler again I just snapped off the little locking collars so I could pull the pipes off.

In this pic you can see the lines going behind the filter to the cooler. There is a plastic clip holding one of the lines to the front subframe which is easy to undo but if you look the higher of the two threaded studs shown here you can see that the pipes are secured to the block with a plastic bracket. This is a bugger to get to. I initially just tried ripping it off but the bracket is very strong! This was the answer, 1/4 socket, various extensions, a knuckle joint and a deep socket. Go in through the filter access flap in the nearside arch.

all this does is hold that bracket on and provide a point to clip a cable to.

 

[FMJ]

With everting else undone I removed the bolts holding the cooler to the oil manifold. A few are a little hard to get to but the 1/4 socket set was just right.

My car has only just had an oil/filter change so I did not drain my oil to do this. You only loose a small amount by undoing the cooler just have something ready to catch it. You will have to top up oil due to the extra cooler capacity anyway. You can see one of the two o rings that provide the seal in this pic.
A cable is clipped to the cooler so you will have to remove that too.

 

[FMJ]

I did not drain the coolant for this job, so when I pulled the two coolant lines I had to quickly plug them with my fingers. I pushed on a silicone u bend as quickly as possible as you will loose a lot of coolant if you let it flow. Here you can see the samco pipe is fitted in the place of the two coolant lines. With two good quality stainless clamps. Always make sure to use something like JCS hi-grip as cheap clamps have perforations that rip the hoses up. I lost about 500ml of coolant doing it this way. Draining and re-filling would have been more professional.

in the picture you can also see the new oil lines which I will come onto in a moment.

 

[FMJ]

The cooler removed

 

[FMJ]

I mounted the new cooler to the bumper bar/beam. The setrab bracket kit is dampened by rubber pads to try to minimise vibrations.

Here the fittings are mounted to the cooler. These fittings are expensive at about £30 each and you need four of them but they are well worth it as they are lower profile, very strong and are full rotatable once tightened so you can get your hose at the right angles. They also have less points of failure then using adapters then fittings on top of that.

 

[FMJ]

I didn’t get any pictures of the bumper bar/beam fitted back to the car with the cooler attached, but you can imagine what it looked like based on the pics above. I made up the Teflon AN10 hoses and routed them across the top of the cooler, around the side of the aircon rad (there is a flexible rubber strip here you can go through). Over the subframe, under the filter and back to the new take off plate. I used the silicone hose cut down the middle and cable tied onto the braided hose as a protective cover wherever it touched anything. If you leave braided hose rubbing on bodywork or other wires, hoses etc it will saw through them due to vibrations. It is a bit tight in places but you can get them routed fairly well.

Just to clarify in some pics the angles make it look like the hose is resting against things but it’s not

 

[FMJ]

Now lurking behind the lower grill. It took just under a litre of oil to bring back up to level.

 

[FMJ]

Observations after doing this are that it is doable yourself, but a lot less hassle to let one of the established places do it did for you.

I have ordered a lower rad hose that will delete the plastic section with the u pipe on it. I just think it’s a bit untidy.

Also as is common with oil cooler moves there is a slight vibration noise as the revs increase due to engine vibrations travelling through the lines. I will sort this out when I change the lower hose.

But it does all work well temps and pressures good with no leaks.

 

[raptor17GT]

nice work, something i need to look into though whether i'll ever need such a large oil cooler is debatable. So many things i'd break doing something this, even after getting the proper tools ha.

Are you going to fit a mesh to the front grill to protect the radiators behind, that air con unit has taken some hits already

 

[GR11M]

I've been waiting a year for my (discounted - summer sale) Mishimoto oil cooler, I'm starting to think I may have to look for an alternative

Have you noticed the engine taking longer to get up to temperature ?

 

[FMJ]

Yeah mesh would probably be a good idea as now the cooler is going to take the stone hits. It is however far sturdier then the aircon.

It gets up to temp just as quickly as before as far as I can tell. As the take off is thermostatic it effectively has no cooler on a cold start

 

[fya67k]

Yeah mesh would probably be a good idea as now the cooler is going to take the stone hits. It is however far sturdier then the aircon.

It gets up to temp just as quickly as before as far as I can tell. As the take off is thermostatic it effectively has no cooler on a cold start

Looks very good job, well done.
My Question is: This Water/Oil Heat Exchanger, is it necessary to actually have it at all?
Why not plug the water connections at the exchanger, remove the water hose/pipework and plug these too. It's only purpose as far as I understand is currently is too get the Oil temp up using the Hot Water from the Radiator.

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