is any amount of coolant "usage" normal in hot climates?...

[ryan roopnarine]

i've noticed that as it gets warmer, i've lost a notable amount of coolant more than i did in the winter. 3600 miles in the past month (2 1500 mile constant operation trips, about 20 hours running each), to/from niagra falls, to from tallahassee fl (330 miles) yesterday has reduced the amount of coolant from the 3/4 resivoir (above kalt)i filled it with before i went to ontario to just above the metal fixture in the aforementioned. i am extremely particular about leaks, and i know for sure that the only thing the car leaks onto the ground are copious amounts of water from the constant a/c operation here in florida. temp has been over 80-85 since april. tia.


ps....i would estimate from gravity measurements that the coolant in there (before adding watter wetter) was at least 70% water, if not higher.

[Tiger]

Some loss is okay... but alot loss is a sign of leakage... let's say, if you loss 1/4 of your reservoir in one week time, then you got a leak. If the same amount in one month is okay... but your got some kind of leak.

Usually no loss is normal... but on older cars, we get leaks somewhere... hoses is usually the primary reason because alot of people never change all of them.

[Robin-535im]

The system should be closed and not have any allowed path out for the coolant, unless it's getting past the filler cap into the overflow tube.

Your cap may be letting it out at too low a pressure - I've seen it happen on other cars where the car doesn't really overheat but the coolant seeps past the pressure valve into the overflow tube. Once it's past the cap, it's out of the system and you'll see your level drop slowly over time. A bad head gasket can do a similar thing... but I seem to recall your HG being replaced about a year ago... :)

If you don't see any blue goo (dried coolant) at the connections, I'd suspect that first of all. Plus - the cap is cheaper than a new reservoir or radiator - and it's always nice to try the cheap things first!

- Robin

[ryan roopnarine]

well i guess i could put the new cap that i keep in my toolbox on and see if that helps..its just that, in winter, the thing would lose about 1/2 cup of coolant between 4000 mile oil changes...an amount that was real hard to keep track of it actually losing. thought it might be heater core, as every now and then i smell a little coolant upon a/c startup. this radiator was replaced right before i bought the car, so i hope that it is a matter of the cap not being replaced along with it. i don't know where the overflow tube is on the radiator, as my tank is integrated (not seperated like m30, 60...).

[Dave M]

I had the cylinder head replaced a year ago (cracks in exhaust valve seats #5 and 3 due to PO's overheat). I have been losing a small amout of coolant since, but assumed it was an external leak. Over the winter I did a lot of work including new rad and rad hoses. For the past month I have kept a tally of coolant consumption both cold and hot, noting outside temp, needle position and mileage (insert nerd). I have noticed about a one 'mark' decline on the integrated expansion tank (I believe you have a 525 M50) over 2000 miles or so, mainly highway miles from the west coast to Calgary return. I haven't been able to locate an external leak so my fear is the obvious. I've pulled the plugs (will post pics and question again later) and found that one side appeared normal (medium brown and toasty) while the other side is noticeably lighter in color. No crust built up, but still makes me think its burning.
Keep us posted, maybe pull your plugs and have a look for interest's sake

Good luck,

[632 Regal]

I put almost 20K on mine since last year and smelled coolant quite often, more often after turns and harsh accelerations. I have not yet changed the antifreeze out and have not added to the resovior, was at the mark but now lower and hardly ever smell the antifreeze thing. I read a while ago that there is some leakage acquired around sharp cornering, acceleration and decelleration which explains the smell. In those miles I "knew" there was a leak but yet havent had to add anything and there is some still in there.

what the hell does this mean??? I have no idea but it's what I noticed.

[JR'Z 525]

My car seems to loose 1/2 inch or so of every 3 to 4 weeks. I've recently seen dried coolant spray on the side of the air filter box and alternator duct. I've always been able to smell a faint hot antifreeze scent from the front of the car when it's parked. My old 87 325 had the same "odor" but I never had to replace much of the cooling system as my 525 has required. Last time I pulled the plugs the color was fine except for a slight bluish spot at the end of the porcelin tip...not a good sign in my opinion. I just keep a close eye on the temp gauges, coolant levels etc. Head gasket is on my list and keep my fingers crossed it doesn't let go before I can replace it...gotta get that cam tool set soon.
JR

[Bellicose Right Winger]

I wouldn't write off the head gasket just yet. Small amounts of leakage from the water pump seal can occur without leaving any traces. As far as your spark plugs, I don't think I've ever found spark plugs to have a completely uniform color...there always seems to be a light and a dark side. I suspect it has to do with the orientation of the plug in the combustion chamber.

Paul Shovestul


I had the cylinder head replaced a year ago (cracks in exhaust valve seats #5 and 3 due to PO's overheat). I have been losing a small amout of coolant since, but assumed it was an external leak. Over the winter I did a lot of work including new rad and rad hoses. For the past month I have kept a tally of coolant consumption both cold and hot, noting outside temp, needle position and mileage (insert nerd). I have noticed about a one 'mark' decline on the integrated expansion tank (I believe you have a 525 M50) over 2000 miles or so, mainly highway miles from the west coast to Calgary return. I haven't been able to locate an external leak so my fear is the obvious. I've pulled the plugs (will post pics and question again later) and found that one side appeared normal (medium brown and toasty) while the other side is noticeably lighter in color. No crust built up, but still makes me think its burning.
Keep us posted, maybe pull your plugs and have a look for interest's sake

Good luck,

[RobPatt 93 525ia @122K]

I'm over in the Ft. Walton Beach area....would be cool to meet/compare notes if the opportunity presents itself....
Rob.


I wouldn't write off the head gasket just yet. Small amounts of leakage from the water pump seal can occur without leaving any traces. As far as your spark plugs, I don't think I've ever found spark plugs to have a completely uniform color...there always seems to be a light and a dark side. I suspect it has to do with the orientation of the plug in the combustion chamber.

Paul Shovestul

[ryan roopnarine]

i "live" in gainesville, sun :) in orlando. fort walton is over by the NW corner? or is it down toward miami....i always thought it was over near the border.

[RobPatt]

Yeah, Ft. Walton is about 3 hours west of Tallahassee.... about an hour east of Pensacola, and I wish it was near Miami, or anywhere closer to some surf! Grew up in St. Pete/Clearwater area.... Florida is a big state!

[Tiger]

That dried coolant is telltale sign of leak... have you checked if your waterpump is weeping or that your thermostat housing (if plastic) is leaking at the seems...

[JR'Z 525]

Old water pump was replaced about 6 months ago because I started getting the spray on the air box. Might be possible to have a defective new pump seal but not likely. Replaced the t-stat housing with an aluminum version at the same time. The pump seal was leaking and plastic impeller was cracked and fixing to disenigrate. Need to do a pressure test and install new hoses but just gotta find the time....
JR

[rickm]

FW is NW Florida near Destin. I just returned from there, it's a pretty place, at least Destin.

[KurtM]

and never find a leak and the resovior is always at the same mark.

Kurt
95 525ia

[Tiger]

yep

[ryan roopnarine]

i went to refill it today, as it appeared as though the resivoir was about to go dry. when i opened the bleed screw, the level of water returned to almost the level i filled it at 3500 miles ago (i can see the watter wetter stain at where i filled it before the trip). this was done with the heat on, as it is supposed to be..i'd estimate the difference to be about 1/2 of one of the graduations, which is well within acceptable for any car to me....is there some special way that i'm supposed to bleed it? the way i do it currently is by jacking the driver's side up, putting the heat on in the cabin/ignition set to just before start, filling the resivoir to where it should be, then pouring water into the bleed hole until bubbles stop appearing in the main chamber...which has resulted in .5 needle left of center operation during two 20 hour drives. anyone care to comment.

[JR'Z 525]

I am curious as to why the reservoir level went from near empty to near correct level when the bleed screw was opened. Does it do the same when you open the rad cap? Could there be a restriction from the radiator to the tank? Before I replaced my leaky old radiator, the tank level would rise about an inch when I cracked the cap, even when cold.
What would be even more puzzling to me is the temp needle reading to the cooler side of the center mark. Mine has always been .5 needle to the right since I replaced the radiator and thermostat a few years ago.
JR

[ryan roopnarine]

it used to be straight up and down until i added watter wetter...good stuff, obvious observable improvement. the level doesn't move when the cap is opened, only when bled.


I am curious as to why the reservoir level went from near empty to near correct level when the bleed screw was opened. Does it do the same when you open the rad cap? Could there be a restriction from the radiator to the tank? Before I replaced my leaky old radiator, the tank level would rise about an inch when I cracked the cap, even when cold.
What would be even more puzzling to me is the temp needle reading to the cooler side of the center mark. Mine has always been .5 needle to the right since I replaced the radiator and thermostat a few years ago.
JR

[Tiger]

How old are your radiator hoses???

[ryan roopnarine]

rad was replaced around 100k, along with thermo and hoses, both look pretty decent, car is at 121k now.


How old are your radiator hoses???

[Dave M]

Where is the coolant hiding? Why on earth would loosening the bleed screw be any different in terms of pressure release than opening the cap? Is there a noticable decrease in rad hose pressure when you allow the coolant into the expansion tank? When the car is stone cold (as stone cold as you can get in Flarida, did you drove or did you flew) is there still pressure in your upper rad hose? To displace half an expansion tank would increase the pressure tremendously. Baffling, absolutely baffling.

While we're on the topic,

Having never seen another M50 engine in operation other than my own, I can't tell how much pressure there should be at operating temp. When you're needle is at noon, and the car has been driven in a spirited manner, is the upper rad hose 'frickin hard'? Mine is harder than any other vehicle I've seen and I wonder, even after the cylinder head job, whether there is some combustion gas breaching the line.

Let us know what you come up with,

Dave M

[ryan roopnarine]

if your hose is exceptionally hard compared to other vehicles, and you still have some warranty on the job left, take it back and make it known immediately....i had the same concern too, as my hose would get rock hard and keep pressure in the tank overnight when the hg was breached....it shouldn't be much harder than other vehicles, even if it functions at 20+ psi. the check was done with an outside temp around 25-28 degrees celsius, with the temp gauge in the blue zone, so it wasn't hot when i checked it. im thinking maybe something is lacking in my bleeding technique, and even though the air pocket is not "substancial" its still enough to displace the water...why i was asking about the "proper" bleed technique.


Where is the coolant hiding? Why on earth would loosening the bleed screw be any different in terms of pressure release than opening the cap? Is there a noticable decrease in rad hose pressure when you allow the coolant into the expansion tank? When the car is stone cold (as stone cold as you can get in Flarida, did you drove or did you flew) is there still pressure in your upper rad hose? To displace half an expansion tank would increase the pressure tremendously. Baffling, absolutely baffling.

While we're on the topic,

Having never seen another M50 engine in operation other than my own, I can't tell how much pressure there should be at operating temp. When you're needle is at noon, and the car has been driven in a spirited manner, is the upper rad hose 'frickin hard'? Mine is harder than any other vehicle I've seen and I wonder, even after the cylinder head job, whether there is some combustion gas breaching the line.

Let us know what you come up with,

Dave M

[Tiger]

You need a pressure tester to find the problem...