Oil Cooler not working

[the gasman]

I need guidance! I have recently bought a very early Sportster, 1997, Sierra/granada suspension and BMW engine. Whilst sorting an overheating issue, i notice that at full temp, the oil cooler and pipes remain cold. I assume there is no oil circulating through the cooler. it is a BMW purolator Micronic PM2433 and the take off for the cooler pipes are clearly OEM also. (Pics enclosed) I am after guidance as to how to procede in sorting the issue and also suggestions as to the origin of the engine. It has a casting date of 1984 on the cylinder head and it is a 3.2L so poss a 732i ??

thanks for your help.

Jim

[copperleaves11]

Re: Oil Cooler not working

Hi. I think this is a 2.5 litre M30 engine, the car once belonged to a former MOC member Andy Rodgers . Whilst I have no personal experience of M30s, I've had a couple of cars with the later M20 unit and IMHO the oil coolers are unnecessary when fitted in a Marlin.

[dogoncrazy]

Re: Oil Cooler not working

I thought that oil would only flow through cooler once a pre - determined temp had been reached

[the gasman]

Re: Oil Cooler not working

thanks for that. I tried removing the thermostat from the take off for the cooler at the block. The oil cooler pipes and radiator still remain cold. I filled the rad and pipes to try to ensure no air lock. Any more ideas. I am heatened by Copperleaves11's assertion that oil coolers are not necessry an such a car ( i will not be racing) so if the overheating issue is resolved once it is back on the road, i might just remove the whole thing but i would be nice to have an answer for why it is not working. thanks again.

[greyV8pete]

Re: Oil Cooler not working

I am not familiar with the Sportster but would question fitting an oil cooler with the feed and return pipes at the bottom? I know you say that you have tried to ensure no air locks but it just seems wrong for it to be fitted that way up? This eBay link shows an original part with hoses connected, which may help? Click on the main photo and you can scroll through several views of the part. Peter.

https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw=1274843+BMW&_sacat=0

[greyV8pete]

Re: Oil Cooler not working

I tried removing the thermostat from the take off for the cooler at the block. The oil cooler pipes and radiator still remain cold..

I suspect that the thermostat will control a sliding valve that re-directs the oil through the oil cooler circuit when it gets hot enough. By removing the thermostat/ sliding valve, the ends of the oil cooler hoses are effectively connected to the same point in the oil circuit, so I would expect zero oil flow, hence those pipes won’t get hot. How about fitting a replacement oil thermostat? Peter.

[Peterx]

Re: Oil Cooler not working

I don't recall thinking too much about flow and return but this is the way I installed the oil cooler on my BMW based Sportster.


M20B28 Installation complete by Sabrebuilder,on Flickr


Your oil cooler appears to be in front of the chassis cross member so even if you get the oil circulating you wouldn't get much air flowing through it.
Maybe you could temporarily flip the oil cooler the other way up just to see if the oil flows?

Hope that helps.......Peter

[greyV8pete]

Re: Oil Cooler not working

I don't recall thinking too much about flow and return but this is the way I installed the oil cooler on my BMW based Sportster.


M20B28 Installation complete by Sabrebuilder,on Flickr


Your oil cooler appears to be in front of the chassis cross member so even if you get the oil circulating you wouldn't get much air flowing through it.
Maybe you could temporarily flip the oil cooler the other way up just to see if the oil flows?

Hope that helps.......Peter

Yes that’s exactly what I would do. BTW gas man, if you want to re-install yours this way I have a pair of brand new J connectors for the oil cooler, surplus to requirements, that you can have for the cost of the postage. Peter.

[the gasman]

Re: Oil Cooler not working

All helpful stuff. GreyV8 Pete is right re the thermostat moving a sliding valve, and it now makes sense that without it, the oil wil take the path of least resistance and still bypass the fliter. Ill put it back before i forget the correct orientation. As for the cooler being upside down, i thought the same so phoned Mocal who assured me that it made no difference and could be fitted in any orientation. There was no further explanation and it does seem count intuitive. I will do as Peterx suggsts and flip it the other way and see what happens. Exquisite looking car by the way!
unfortunately all of thhis will have to wait as i have just broken the electrics. I was Attempting a compression test with the HT leads disconected and did not take sufficient care to stop them earthing. A couple of spakes and now nothing. It is as if the battery is disconected. No lights, no instruments ,no nothing. I hope it is a simple fix and not terminal. I cannot find any blown fuse so am worried. Any suggestions there would be appreciated before i face the embarrassment and cost of trailering it to a garage.

Jim

[Peterx]

Re: Oil Cooler not working

No lights, no instruments ,no nothing. I hope it is a simple fix and not terminal. I cannot find any blown fuse so am worried. Any suggestions there would be appreciated before i face the embarrassment and cost of trailering it to a garage.

Jim

I can't think why, but it sounds like you have blown the main fuse / fuseable link.
It will be in the main supply cable from the positive battery terminal to the fuse box.

On my Sportster it looks like this (black oblong box in the centre of the photo below) but it could be a different on yours.

Fuseable link by Sabrebuilder, on Flickr

[greyV8pete]

Re: Oil Cooler not working

The HT normally goes to earth, just via the spark plug gap, so I can’t see why that would cause the problem. My worry is that one of the loose HT leads has fired HT into a sender wire or similar that has fried the ECU. Hope not!

BTW a bit off topic but as some disconnected thoughts, I have read somewhere that unlike the old school technique of pulling the plug leads off one at a time, when checking for a misfiring cylinder on an engine fitted with electronic ignition and fuel injection, it is safer to pull the injector plug off. That still identifies the duff cylinder without turning the ignition system into a defibrillator! Also on my Rover V8 injection engine the immobiliser shuts off the ECU and fuel pumps but still allows the starter to crank the engine. I don’t know if that is the same with the BMW? I have also heard that repeatedly cranking an engine with the injectors working but the plugs not firing produces a very fuel rich exhaust which can mess up oxygen sensors (or maybe it was the cats that it messes up?). Peter.

[the gasman]

Re: Oil Cooler not working

Thanks peter,
Ill re-insert the thermostat and invert the cooler and see what happens. If it warms up and i can still fir the nosecone ill get in touch with you again for the J connectors.

My fusible link is the same as in you picture and unfortunately still has continuity. I am looking for something else. Sierras had a fusible wire in one of the high current circuits so i am looking for that. It might have made it into the build. Although built by Marlin in 1997, there is alot of redundant wiring in the loom and maybe this was transferred. Thanks again for your help. It is good to have this support. When i got the car in August i had an exciting list of what i wanted to do with it. Not really done any of that list yet as the other things have cropped up. I try to view it all as part of the Joy!

Jim

[the gasman]

Re: Oil Cooler not working

I fear that i have fried the ECU too, i just dont want to think about it yet. Also i cannot imagine that that would cut off supply to all the electrics, dashboard lights, lights, hazards etc. nothing lives . In the event that i have seroiusly damaged things, it will need to be trailered to a garage that is skilled with:

Kit cars in general.... some "engineers" are put off by the concept
Old BMW engines.
Electronic ignition and ECu from the 1990s ie old stuff
tuning Webers..... it is popping back on the rear carb and all are running rich.
Poss New ECUs in event of serious damage

Any ideas???? I have details of a garage nar Preston ( ie local ish) called john Clarkson Autos who advertises in Complete Kit Car magazine and has good reviews and interesting car photos on his website but any personal reccommendations would be good.

Jim

[greyV8pete]

Re: Oil Cooler not working

I would start at source. Get a multimeter and check the battery. Then check the battery Earth is clean and secure, both at the battery and the earthing point. Has the car got an isolator switch that has been knocked off during all the excitement???

Then start checking for 12v between an earthing point and all the wires that lead from the battery to the fuse board. The horn is non ignition so should work right away but other components will need the ignition switch on and some will also need the immobiliser deactivated and of course lights etc will need the appropriate switch “on”. Take your time and work methodically. Make a note of what you have checked and don’t assume anything. Coincidences do happen and even the battery may have failed! Peter.

[chris_cussen]

Re: Oil Cooler not working

With the exception of the starter motor my battery goes through a 100 amp fuse to the rest of the circuits. If you have one fitted and have blown that, then the car will be as dead as a dodo.