Has anyone succesfully removed the big side plug (15/16" wrench) on the induction side of the 6 cylinder engine to flush out the block as described in the service manual? I put a socket and breaker bar on it but couldn't budge it. This might be one of those "better left alone" jobs since I don't have an overheating issue, just thought it would be nice to do a proper clean out while changing the antifreeze. Engine is in car, not on stand, so somewhat difficult to get good leverage on the plug.

Barcho
'86 XJ6

 

I failed on this - see my thread Removing XK engine plug - Jaguar Forums - Jaguar Enthusiasts Forum
I reckon a 3/4 drive 6 sided socket + breaker bar would be needed.

 

the drain bolt for rhe block is in the exhaust side of the block.

 

Some place or aI read that the big was actually a plug for the port to fit a block heater in cold climes. And, a real bear to remove.

On You Tube, I've watched "Watch Wes Work". In the Ohio rust belt. As a general mechanic man different critters come in to his shop. Most of the time, he gets rusted fasteners to come free. Blaster, heat and a vibration tool. Work back and forth just a tad til they loosen...

Carl

 

I Failed as well. Tried a large breaker bar, then an impact wrench, which usually removes stubborn plugs etc. No cigar I'm afraid.

 

I have never read about anybody managing to remove this large plug and I have owned Jaguars on and off since the 80s ! It is there to take a block-heater for use in very cold winters like you get in the northern states of the US. Very few were ever fitted, and Jaguar made no other provision in the engine bay for them, it was entirely down to the dealer or the car owner how the cable was secured. The plug was probably fairly easily removed shortly after the car was made, but as time allowed rust to build up it just gets rusted in. The way to really clear out the coolant jacket is to remove all the core plugs, plus the plate at the rear of the block, (this was a core plug on earlier XK engines), and flush through and pokew around with a bit of wire. I did this when I rebuilt my XJ Series 3 engine in the early 90s

 

A little back from the dipstick near the bellhousing. I replaced the plug with a brass tap I found at a local market.
I can push a 1/2" garden hose on it connected to the presuure washer and flushes out plenty of crap. I did It recently when I had my radiator recored.

 

o1xjr,

correct, older XK engines came with a tap.
I think up to the 420.
The 3.8 in my S type has the tap instead of a bolt.

 

Yes, that's right. My 2.4 litre Mark 2 had a tap, and my XJ6 had a bolt. Frankly, so much crud accumulates at the back bottom of the coolant jacket that it is normally necessary to remove either and poke about with a piece of wire in order to clear a passage for the coolant.