Oil cooler replacement, saved a few quid

[Gasman GT3]

A couple of weeks ago one of the oil coolers gave up, which I caught before I lost all the oil and more serious damage could have been done.  Now for those that don't know these can be a right bugger to change for a couple of reasons, first getting at them, especially the top union on the drivers side in a Delco brake equipped car, and secondly steel unions on ally fittings, not to mention the retaining bolt which in typical Lotus fashion will probably be very corroded and snap off with the first tun of the spanner, which mine did.

After very carefully moving some of the ABS kit to get access to the top union and managing to get a 30mm spanner on it rather than the union undoing the threaded part just snapped off the oil cooler leaving it inside the union of the cross over pipe, unsurprisingly the same happened with the bottom union.

Obviously this then presents a problem, how to get the broken bits out of the unions on the oil supply pipes, or face the expensive option of replacing the entire supply pipe, and in the case of the cross over pipe that goes through the front boot the very real need to replace the other oil cooler too!  After a chat with Dave "Changes"  he said the best route with the bottom union was to just cut off the hose as close to the union as possible then just get a replacement union from Hydrafit in Wolverhampton.  There then should be just enough hose to remake the joint using double Jubilee clips to seal it.  A trip to Haydrafit in Walsall St Wolverhampton on Friday saw me leaving there with the exact same 5/8 elbow as fitted to the hose originally and 4 high quality Jubilee's for the princely sum of £8.50, far cheaper than the £120 for a new hose from a Lotus specialist.  If you did need an entire new hose they could make one up for you with the correct fittings and proper swaged ends for a fraction on the cost of a Lotus replacement, worth bearing in mind.

The top union presented more of a problem.  Fist option was to try and get the fitting out of the union with a couple of large spanners, but to no avail as I just couldn't get enough purchase without a vice, so the only other option was to get the hose off the metal transfer pipe.  Problem with this is that the hose is swaged on to the pipe with a very substantial fitting, which I attacked vey carefully with a Dremel fitting with a small grinding wheel cutting it along its length on two sides to split it open being careful not to damage the pipe.  Then it was a fairly simple job to get the broken fitting out of the union  on the bench in a vice.  Like the bottom hose there was enough slack to reattach the hose to the pipe with a couple of Jubilee clips.  

All fittings have been liberally coated with copper slip and a nice new stainless M10 bolt used to secure the cooler to the body.  

Below are a couple of shots of the knackered cooler in situ and the new cooler and all the bits to refit it.

Thanks to Dave for his sage advice which potentially saved me a small fortune.

 

leaky knackered cooler in situ once the ducting and under tray have been removed

 

New Setrab cooler and fittings prior to refitting 

Edited March 10, 2013 by gasmangt3

[dodge1979]

Ade, ive got a spare set of oil cooler pipes if you had ended up needing them. And I have a man who can make them up as per originals for a seriously lower price than the originals too..if anyone else is in need!

[mr.oogieboogie]

i had an oil coller burst a while a go. and teh alloy connector snapped so i used some caustic soda with watr in a jam jar, left the pipe in for a few hours and no alloy left. only a couple of pounds from boots the chemist.

[Gasman GT3]

I tried that Pete, as I use caustic to strip paint from model cars but no joy

[mr.oogieboogie]

Worked fine for mine. I did change it once and i used a full jar and not too much water the jar got red hot.

[fjmuurling]

Worked for me as well, first time not really but the second attempt I upped the concentration and a couple of hours later clean couplings without aluminium bits.

 

Freek

[OwenGT3]

I replaced my o/s cooler last year, leaked in the bad winter last year. Ended up also replacing the pipe from the cooler to the engine with the help from Andy Clements, definitely a two man job. I did spend four hours though dremelling the alloy thread out of the front cross pipe union to save it, which worked. I did dremel the pipe from the cooler to the engine, but it couldn't be saved. I got all my parts from SJ.

 

Like what's been mentioned, I had to purchase a set of crows feet spanners to do the upper nut up. All in all it was a massive job for such a small item, especially undoing the cable ties in the tunnel, for Lotus, easy when there is no body sitting on the chassis on the production line installing, not so easy with a body on the chassis. The simple answer for Lotus would have been to add a steel intermediate adaptor between the cooler and the pipes. This way you have steel on steel and when the thread shears off in the adaptor you just replace those parts. I suppose weight and the cost of fitting four to every car would have sent the figures two high, cost and weight! 

 

Here are pictures of my fitting

 

http://www.flickr.com/photos/owengt3/sets/72157629389193265/

Edited March 14, 2013 by OwenGT3

[S4-94]

Hi all

Sorry for restarting an old thread but unfortunately my S4 is dropping oil from the drivers side oil cooler.

I’ve looked and the union at the bottom is all wet so clearly the issue.

I spoke to my usual garage and he’s explained the issues here and said realistically it’s a £1000+ job as I’m likely going to need both coolers, all three hoses and a lot of his time to sort properly feeding the new hoses back through the chassis.

Unfortunately, my S4 has rinsed me this year (new clutch, ABS, rear brakes) and I just can’t afford another big outlay, plus I know she’s going to need new belts next year so I’m forced  to have to think of alternatives.

This approach of just replacing one cooler and joining hoses seems like the most economical solution albeit it not perfect.

It all sounds doable but just wondered what access is like to the cross over hose join with the solid pipe? Is that accessible?

Thanks all.

[Chillidoggy]

It depends on whether or not the steel unions have welded themselves to the alloy cooler nipples. I use an adjustable crow foot spanner on the hose nut, and a stubby spanner to support the cooler hex nut. If the alloy shears, and you want to reuse the hoses, then the alloy can be dissolved in caustic soda solution. Personally, I’d replace both coolers. If one is leaking, the other one may not be far behind.

The hoses are a bit awkward to change, but gear change master removal gives better access for that.