Oil cooler bypass

[simon291971449]

Hello. Happy new year! Possibly a very stupid question to start the year. If I was going to fit an oil cooler bypass on my 91 4.0 facelift, does the new part go on at the engine block end or at the other end of the two.pipes where the cooler would have been - ie in front of the radiator? The left hand pipe as you look at it is weeping oil as it goes into/comes out of the actual cooler.

Also, can I still buy the bypass part new from anywhere, and is there a guide anywhere to the fitting process?

Many thanks

Simon

[ptjs1]

Simon,

It's very easy to do. Effectively, you fit the bypass loop on the oil filter housing block on the engine, replacing the output and input ports from the oil cooler pipes. So, on the diagram, you need parts 3, 4, 5, 6 & 7.

https://parts.jaguarlandroverclassic.co ... nd/jaguar/

Not all of the parts are still available, but with the part numbers, you can probably find many of them on eBay or similar. The O-rings you could source anywhere. If you get stuck, I can measure the O-rings for size for you.

if you can't source the parts, I think you COULD do it a different way, which is to remove the sandwich plate and just bolt the oil filter plate direct to the block with shorter bolts. Then you wouldn't need any parts. That would seem to just push all the oil through the filter. Although I guess, IF the filter failed (extremely unlikely) that you COULD get an oil flow failure? Maybe have a quick chat with David Marks and see what he thinks of my second suggestion?

Cheers

Paul

[poprivet]

Here are photos of both sides of that adaptor. It's been so long since I had it apart I can't remember the details but I think the valve would by-pass the filter in case it blocked? Hopefully someone can say for certain.

The adaptor U piece is the way to go really.

[ptjs1]

I agree with you Pop. It should really be done as Jaguar designed which leaves the bypass valve in situ, I just suggested the alternative as I know of at least one US owner who has removed the sandwich plate and done it that way. Not my preference, but each to their own.

Paul

[simon291971449]

Thanks both for your very helpful replies. Have found a used bypass pipe part and have ordered new O rings. Will let you know how it goes. Simon

[simon291971449]

Hi folks. Bit of a disaster. Removed the oil cooler pipes from the filter housing, fitted the bypass loop with new o rings and the new longer stud which came with it. Got rid of all the old oil cooler gubbins. Brilliant, I thought. Started the car, and was about to get out to look underneath for any drips from the new bypass, when the car spewed litres and litres of oil onto the garage floor in about 10 seconds, from where exactly I'm not sure. It was far too much oil to have been just been the o rings on the new bypass, and it had definitely clicked into place. And I'm (pretty) certain there was no other pipe I'd disconnected and forgot to reconnect. If it's any clue, the oil had come out with such force it was all over the air filter and left side of the bonnet underside ie the top of the engine! One thing I should maybe mention. Before fitting the bypass, I pressed home one of the cylindrical junctions (with the o rings) into the filter housing to trial fit it. It clicked in nicely, and was a snug fit, but I couldn't get it back out ( I needed to remove it to get the original stud out). To get the junction out I had to put a hook up it's middle and pull downwards. I was aware the hook had initially gone up too far, and it felt as though it had impacted something (soft?) further up inside the filter housing. What's up there, and might I have damaged something up there with the hook? I suppose another alternative theory is that I accidentally dislodged/ disconnected/broke something vital to oil retention while working under the car (or while removing/pulling through the oil cooler pipes, which I'd had to cut). Perplexed! Grateful for any advice or theories on the carnage I've caused.