I havent checked the sensor yet. It might be the dash faulty too as the fuel gauge and water temp doesnt work either.

Too early to get right into it yet. Hopefully friday I can get the tranny linkage back together, then flush and fill the rad. I'll check the sensors while too.

 

Marathon,,,, or race?

 

Iron man lol.

I want to just move it out of garage, turn it around, wash the engine bay, and drive back into garage. Once its nose in the garage I can start work on everything else as I can then do test runs on it without the exhaust going everywhere instead of outside lol.

Should mention my driveway is sloped so it's a beast to push into the garage. Wont leave the garage until spring then.

 

I can relate

 

It is the sensor or the gauge. The V12 oil pump cannot fail!

 

Pretty sure it's the gauge. I know theres a little rust behind the actually cluster.

Also read these v12 read low anyways and with 10w30 it's even lower.

I know theres oil because I just put 12 L in and no pool under the car lol.

Oh Greg I looked and dont have a drain **** for the Rad. And why did they put the overflow behind the damn fender lol.

 

The easiest way to drain the rad if you have no tap, is to undo the banjo bolt and slide a thin poly tube down the side tank and syphon the coolant out. This is a Grant Francis tip. Bows to the Southern Cross.

 

I can do this to flush as well? I'm pretty sure there is barely any fluid in there so I want to run lots of water through and try to get as much out as possible. I'm gonna pull the rad like u mentioned before once the snow flys

 

Just pull the rad, once out have a go at flushing the block, with the thermostats removed.

 

Get some decent 20w50 oil in there. Our V12s weren't designed for modern thin stuff. My pressure was low on previous owner 10w40. Much better now I've changed it.

Paul

 

Went with thin because it was cheap. I'll put good oil in once I get the engine to stop leaking lol.

Also canada we like thinner oil for winter

 

Paul
I respectfully disagree. I do not assume you are of this view, but generally there is a belief that the oil is a cushion between the metal surfaces of the bearings, and that the thicker the cushion, the more comfortable the bearing will be, and that oil pressure forces the "cushion" into the bearing and that the higher the pressure the better the cushion will work.
My information is slightly at odds with this view: in a plain bearing the rotational action of the bearing journal itself pulls the oil through, the oil pressure is there to ensure there is oil outside the bearing to be pulled through, not to force oil though the bearing. A plain bearing will always be adequately lubricated as long as there is oil at its entrance point to be pulled through. Think of a mangle drying washing, however hard you push the wet shirt against the rollers, it will not go through them. Turn the handle and the wet shirt goes through. Oil in a bearing acts like the shirt. A plain bearing under load can run in a bath of oil 2/3rds of the way up it quite happily for an indefinite period, all the while in effect having zero oil pressure. Most lawn mowers work like this, or a variety of it.
Oil pressure is a factor of how easily the oil is getting through the bearing; not how effective the bearing lubrication is. A hose with a huge pump feeding it will show high pressure, but as soon as you open the tap, the pressure drops. Were an engine to have an electric oil pump that worked off the ignition, engine not turning, its oil pressure would be sky-high but no bearings would be being lubricated. A hot engine has lower oil pressure than a cold one, not because the bearings are being worse lubricated, but because the cold oil is not able to flow through the bearings as well as it does when hot - in other words, the bearing has more trouble pulling the oil through when cold, resulting in a higher pressure building up before the bearing.
So I believe in a thin weight for cold oil (I use 5w-20 or 30), which while it will show lower cold oil pressure, actually means the bearings are better lubricated when the engine is cold. When the oil is hot the stuff is so runny anyway, the difference between 20, 30 or even 40 is not much. In fact some time ago i posted calculator link that allowed the user to input oil temp and oil weights and showed viscosity, and this bore out the point.
Now we all know that oil discussions are forum dynamite, and i as much as anyone have my oil prejudices (fully synthetic only in my case!) but I truly believe the "thick oil is best" mantra is mistaken. My car had done 33,000 miles when I bought it, now something like 140,000, so the last 110,000 have been on fully synthetic low cold viscosity oils. The camshafts show no measurable wear at all. The bottom end seems fine (maybe I am tempting fate!) so if oil weights make any difference at all to our engines, and they may not, my experience has been low cold viscosity does no harm.

 

Well put. Ive never used anything but 10w40 in any vehicle ive owned where i did the oil changes. and when its -20C and below, I cant think of anywhere were I would use a heavier oil in Canada, maybe BC. Thats why we have block heaters as well. to keep that oil a little warm so its an easier start. This Jag has a block heater installed in it. I dont plan on running it in winter anyways lol. Any vehicle ive owned has either shown in the manual 5w30 or 10w30. so the only real choice you have to make is regular oil or synthetic. I went with regular as the cars been sitting for awhile and I just wanted oil in it to get it running.

 

Greg,

That's a great post, thank you! I don't disagree at all with your wise words on bearing lubrication. And your own experience on low cold viscosity oils over 110,000 miles is a really interesting insight.

One question that does occur to me is where is the sweet spot between enormous oil pressure that may a reflection that bearings are not able to be lubricated effectively when cold; and zero oil pressure which may also indicate insufficient bearing lubrication is occurring? I guess I've always (perhaps naively?) believed that if I can see a good pressure reading, I have sufficient oil available to believe that my engine is being lubricated. And also whether the lower machining tolerances and perfections in engine components of older-generation engines necessitates a higher oil viscosity to "fill" those gaps effectively? My other assumption is that "thicker" oils will not find the inevitable gaps in my sump plug, cam covers and front cover so easily!

Cheers

Paul

 

Rescue119,

I'm interested in any experience you have of the block heater in your V12? A few years ago, more out of curiosity than anything else, I amended the bottom hose configuration of my 4 litre AJ16 to incorporate one of the 110v heaters that were installed on Canadian and US(?) XJSs. However, whilst it does get some little heat into the coolant and cylinder head (based on IR thermometer readings), I can't get it anywhere close to operating temps even if left on for some hours before starting. So, I've always thought of it as frost protection, rather than a real pre-heater. I suspect that I'd need one screwed into the block itself to really get some heat into the engine. Does yours screw into the block or, like mine, does it just fit into the bottom hose?

Cheers

Paul

 

I havent followed the cord just found the plug wrapped up. but block heaters...well are installed into one of the frost plugs in the engine block. its not suppose to keep the oil at say operating temp just to keep the oil from freezing/crystalling. Even at -40C ive seen the oil temp at 1 C. Those mornings when I have forgotten to plug in my vehicle, even brand new vehicles, they taking a few extra seconds to crank over if they start at all. But if you are experience -20C , -10C if older and not used often, or below you dont really need one. Im back in ontario now where those cold days are very rare compared to out west so I will probably never have to plug in a vehicle again until i end up in a colder climate

 

Thanks for that. As you can imagine, being in the UK, I have even less real need of a pre-heater than you do! I just did it....because I could! I've now just looked up the Jaguar parts website and realised that the V12 heating element also just sits in the bottom hose rather than being a true block heater.

Cheers

Paul

 

A hard question Paul! I would say, as a rough guess, any pressure that is sufficient to keep the warning light off is fine. An engineer friend of mine said quite seriously that as low as 2psi is fine in an engine as long as there is sufficient oil there for the bearing to pull it through. The real purpose of oil pressure is just to ensure there is oil there for the bearing to wind in, so a decent pressure (say 25 psi plus when hot) in a road car engine will do it, and be sufficient to overcome any inertial effects on cornering etc etc.. "filling gaps" etc etc is an example of the "cushion" thinking I feel is erroneous, you cannot force oil through a bearing by external pressure! After all, it would have to overcome the piston pressure in the crank to do so!

 

The V12's are in a alloy fitting that goes into the lower rad hose. The 6 cylinder XJ40 does this too, and the X300's have a moulded in boss into the lower rad hose.

Block heaters are a science into themselves, and much depends on the objectives and the fluid they go into. A heater can have higher wattage that goes into coolant vs oil, because water has a higher heat capacity, and it is also less viscous, so there can be a thermal syphon set up in the engine and cause the coolant to circulate. The limits of power per area of the heater element is much lower if it goes into oil, be cause the oil doesn't flow as well and too much heat can locally coke the oil.

Jaguar is reasonably unique in putting the heaters into he hose, rather than into the blocks water jacket itself. They did that on the earlier XK engine, it has a boss on the right side of the engine. The Jaguar heater element is only 400W, which is quite a bit smaller than most domestic Canadian cars would use. They are typically 800W or greater. The X Type is an exception, it has an element that goes into the block, I think because the basic block started as a Ford design.

The basic idea of a block heater is to warm the coolant, and oil to a certain degree to make the engine easier to crank. In the V8 carburettor days it also heated the carb and the fuel in the float bowls to allow it to vapourize easier and then the engine would start easier. It isn't to have the engine at operating temp before starting, it is to put some heat into the engine that when it is very cold makes the difference between starting or not starting. It will warm the oil to a lesser extent, and that also reduces wear on startup if the oil flows faster through the engine.

 

I saw a presentation by an Esso lubrication engineer years ago and his recommendation was to use the lowest first number possible and then match the second number to whatever the manufacturer calls for. Thus if the original spec called for 10W30, you should use 0W30 if available.

The 0 gives great pumpability at cold startup, while the 30 matches the spec for hot viscosity. 90% of all engine wear occurs at starting, so the idea is to get the oil flowing into the engine as soon as possible.