Bleeding the cooling system
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There are different opinions on what works for filling and bleeding but most owners use some variation of the same basic procedure. Here's the process I've used on V12 Jags. It's not difficult, just messy.
Elevate the front of the car about 8" and then elevate the left front another 2-3" beyond that. Set the climate control for max heat so the heater valve opens.
Remove the bleeder plug from the left radiator tank. You'll see an access hole in the radiator upper mounting panel. The plug is some arcane size but you'll find something in your toolbox that fits.
Remove the caps from the expansion/header tank and from the filler pipe at the front of the engine....up there by the A/C compressor.
Add coolant/water to via the filler pipe until it reaches the bottom of the pipe. Start engine, set heater control to max heat. Let it run at idle until it warms up. Peek inside the filler pipe every minute or so and top up as needed.
When the engine gets warm increase the idle to about 1000-1200 rpm (a helper is helpful here...or just wedge a little something in the throttle linkage to hold it slightly open for a high idle.
Let 'er run and run. Give the upper radiator hoses a few squeezes now and again. Keep checking your coolant level in the filler pipe and top off as needed. Eventually you'll see some coolant coming out of the bleeder. That's good. Wait a while longer and (hopefully) you'll see coolant *really* pouring out of the bleeder. (How much? It's one of those "you'll know it when you see it" things..very messy)
When it's *really* pouring out of the bleeder hole, put the plug back in. Wear some gloves so you don't get scalded. If you can't get the plug back in thru all the gushing, shut off the engine and do it....but I like to leave the engine running if I can. Not worth getting burned, though.
Top off the coolant in the filler pipe...I go right to the top but some fill just to the bottom of the neck... add a quart or so to the expansion tank if you suspect it might be low, button everything up, and yer off to the races. If you've overfilled the excess will be pushed into the atmospheric tank mounted inside the fenderwell. If you've *really* overfilled the excess will exit the atmospheric tank and end up on the ground.
Lower the car and clean the driveway :-)
Cheers
DD
Elevate the front of the car about 8" and then elevate the left front another 2-3" beyond that. Set the climate control for max heat so the heater valve opens.
Remove the bleeder plug from the left radiator tank. You'll see an access hole in the radiator upper mounting panel. The plug is some arcane size but you'll find something in your toolbox that fits.
Remove the caps from the expansion/header tank and from the filler pipe at the front of the engine....up there by the A/C compressor.
Add coolant/water to via the filler pipe until it reaches the bottom of the pipe. Start engine, set heater control to max heat. Let it run at idle until it warms up. Peek inside the filler pipe every minute or so and top up as needed.
When the engine gets warm increase the idle to about 1000-1200 rpm (a helper is helpful here...or just wedge a little something in the throttle linkage to hold it slightly open for a high idle.
Let 'er run and run. Give the upper radiator hoses a few squeezes now and again. Keep checking your coolant level in the filler pipe and top off as needed. Eventually you'll see some coolant coming out of the bleeder. That's good. Wait a while longer and (hopefully) you'll see coolant *really* pouring out of the bleeder. (How much? It's one of those "you'll know it when you see it" things..very messy)
When it's *really* pouring out of the bleeder hole, put the plug back in. Wear some gloves so you don't get scalded. If you can't get the plug back in thru all the gushing, shut off the engine and do it....but I like to leave the engine running if I can. Not worth getting burned, though.
Top off the coolant in the filler pipe...I go right to the top but some fill just to the bottom of the neck... add a quart or so to the expansion tank if you suspect it might be low, button everything up, and yer off to the races. If you've overfilled the excess will be pushed into the atmospheric tank mounted inside the fenderwell. If you've *really* overfilled the excess will exit the atmospheric tank and end up on the ground.
Lower the car and clean the driveway :-)
Cheers
DD
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Join Date: Mar 2008
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I've been running older Jags for 20+ years and *still* learn something new from others almost every day.....sometimes before I've finished my first cuppa coffee in the morning!
Cheers
DD
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#7
If it makes you feel any better, my car leaks at the top hat seals and I regularly have to refill it (every 2-3 months). I never bleed the system from the banjo and it always cools just fine.
Not at all saying there is no benefit or reason to do it properly, just trying to let you know that you don't need to worry. Just because there is a very specific method does not mean its the only way that will work. If you system doesn't leak, by all means spend the extra few minutes to bleed it out.
Not at all saying there is no benefit or reason to do it properly, just trying to let you know that you don't need to worry. Just because there is a very specific method does not mean its the only way that will work. If you system doesn't leak, by all means spend the extra few minutes to bleed it out.
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#9
This car had an small engine fire at the rear of the engine, it burned some wires.So the leci could get to them, I removed the fuel rail and what I thought was the coolant crossover pipe at the rear of the engine.When I removed the pipe I noticed that there was no water thereI have reassembled the parts, but I thought I would make sure water was getting to the crossover pipeIts notI tried blowing in to the filler pipe (lung pressure) but no luckIs this crossover pipe a water pipe, it dose have a T and a small pipe going some where If it isn’t, what is it and what is the small pipe for.
thanks
thanks
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#12
#13
#14
The vacuum in the intake manifold is a proxy for the extent of demand for power from and load upon the engine (ie low vacuum=throttles wide open=need power; high vacuum=throttle closed=not much power required). This, together with the throttle position sensor give inputs to the ECU which enable the pre-programmed ECU chip to decide how much fuel to squirt into the cylinders. At least, that is my layperson's understanding.
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The vac line goes ALL the way to the ECU, then through the casing, to a smaller hose inside, and terminates at a Sensor on the circuit board.
Less vac = more fuel
More vac = less fuel, and then, as Greg said, things like engine temp, throttle capstan position, all do what they do to run the engine.
Dinosaur stuff by todays standards, but this is all 1960's technology, just fine tuned a tad for the HE, and a tad mire for the Mareli beasts.
Those snaps also show the throttle spindle pivot bush AWOL, and that engine will NEVER run right without those 2 bushes, one each side, being in place and in good shape.
Less vac = more fuel
More vac = less fuel, and then, as Greg said, things like engine temp, throttle capstan position, all do what they do to run the engine.
Dinosaur stuff by todays standards, but this is all 1960's technology, just fine tuned a tad for the HE, and a tad mire for the Mareli beasts.
Those snaps also show the throttle spindle pivot bush AWOL, and that engine will NEVER run right without those 2 bushes, one each side, being in place and in good shape.
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knares (04-18-2018)
#17
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#19
Ah, that's what I'm doing wrong. I don't generally drink anything stronger than tea....
Incidentally, prices are very much not down over here in Japan. The most expensive currently on sale is this US$42,000 (plus on-road costs) convertible, and the average asking price is US$24,391 (plus on-road costs). I think someone must have been blabbing....
Incidentally, prices are very much not down over here in Japan. The most expensive currently on sale is this US$42,000 (plus on-road costs) convertible, and the average asking price is US$24,391 (plus on-road costs). I think someone must have been blabbing....
#20