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I've recently purchased a 94' 540i and I've been having a few problems. I'm getting a gurgling sound coming from the dash once the car has come to a halt and now have no heat what so ever. Once every month the coolant also seems to dissapear. I'd appreciate any suggestions you guys may have.
Does the car presently have the proper amount of coolant in it? Loss of coolant can be caused by myriad failed components.
The heater core is gurgling because there's probably air in the system. That, or there's a big enough flow problem that the coolant is boiling, which is highly unlikely because there wouldn't be much of an engine left after a short while of that.
If there are any indications of a blown head gasket, then we've found out why the car was being sold to begin with... It's always a good idea to have a competent shop do a prepurchase inspection before buying one of these cars.
Search heater core, M60 water pump failure, and head gasket failure. If it were my car, I wouldn't drive it until the problem is found and fixed.
best, whit
any spots of fluid under the car? Look at where the radiator hoses connect to the radiator and thermostat housing. The waterpump belts and ALL hoses are maintenance items. I doubt it's a head gasket, does the engine temp stay right in the center of the gage?
Cheers for the comments guys. Yes, the temp has always stayed dead center and I've not seen oil in the water or water in the oil as yet. It does smoke quite a lot on start-up but once driven for a while it goes away. No sign of water on the ground and I top it up to the correct level once it has vanished. It's really odd as the coolant seems to disappear all in one go about once every month and not at a graduale rate.
Some questions on head gaskets if I may. Is it possible for the coolant be going out through the exhaust system without seeing other symtoms - i.e water in oil? I also have an engine misfire which as a result means I don't have the correct amount of power on acceleration. Can that be a sign of failed head gasket too?
I will be doing a compression test soon just to be sure but any advice you have at this point would be great.
bleed the radiator ,screw on top, sounds like air in system
HAHAHAHA...we V8 owners dont have to deal with this fiasco.
Edit: with a name like straighteight I am wondering where he is from.
if the headgasketis leaking into a cylinder its possible it passes to the exhaust. Examine the plugs when you do a compression test to isolate the dead cylinder. It still may have good compression though.Quote:
Originally Posted by jasons525
After a long week of British rain I've now completed the compression test (see below). Could you guys tell me what you think of the results.
I also looked at the plugs and most seemed fine. A couple seemed a little black with some corrosion (cyl 1&5). What does a spark plug on a dead cylinder look like?
Cylinder No 1: 160psi
Cylinder No 2: 170psi
Cylinder No 3: 155psi
Cylinder No 4: 155psi
Cylinder No 5: 155psi
Cylinder No 6: 157psi
Cylinder No 7: 168psi
Cylinder No 8: 180psi
No heat can be simple... Heater control valve do get stuck once in a while... bmwe34.net shows you how to unstuck it... bascially you have to loosen a few screws and use a hammer to tap it loose. Do this when engine is cold.
As for your compression test... it is not so good. For our V8... it should be alot higher... The figure is fine for any other engine but BMW specify higher for the V8.
don't think thats the problem, if you have a blown headgasket and coolant getting into the combustion chamber the plug usually is scrubbed clean frequently with a light coating of rust on the electrode, if yours are black or tan then thats not the problem most likely. If your pressure cap is releasing at too low a pressure then it can lose coolant there while your driving and you won't even notice it since it dumps out under the car. There's many places that you can have a cooling system leak on the m60 and not notice it easily. You need to take a radiator pressure tester and pressurize the system to normal pressures and then just watch for leaks, give it 20 or 30 minutes with it pressurized for a leak to show up under the car
12 to 14 bars is the normal compression. 12 bars equals 174psi approx. I wouldnt worry about your compression numbers, there's too many variable when you do the test. Did you hold the throttle body wide open? if not then your numbers will be lower, did you hear each the cylinder stroke at least 8 times on each one or until the gauge doesn't climb any higher? Your numbers look good enough to indicate that thats probably not the problem. Your more concerned about large variances between cylinders.
Quote:
Originally Posted by straighteight
due to the heat created on that side of the engine bay (unlike I-6 M20, M50, M30, S38). The necks on the pumps crack apart similar to the way the radiator necks crack. I have seen 3 aux water pumps that were pushing out coolant when running because the hose was seperating from the aux pump with the neck inside of it.
Usually you see coolant on the ground as a result.....have you seen this?
edit: sorry, you said you don't see this.
Can you see dried up coolant covering anything in the engine bay?
Go yank the hoses connected to the aux pump and make sure they are tightly fitted and the aux pump necks are not broken.
Quote:
Originally Posted by straighteight
Do you park the car on a slope with the front pointing downhill? I had the same thing along with loss of brake fluid for the first month I owned the car. I have a theory explaining the brakes...the gromets on the lines going into the top of the master cylinder were leaking, but the leaking brake fluid swelled the gromets so they have not leaked in the last 6 weeks. The same thing happened with the coolant (the low fluid message came on about once a week for the first month and then stopped) but I do not yet have a theory for how that stopped.
Hope the brake fluid was neutralized so the car still has a front end ;)
The grommets are cheap and easy to replace. Takes 10 minutes the first time around. They commonly leak, and I doubt it's smart to not replace them for safety reasons.
best, whit
Wait hold on... so are you saying DON'T replace them or DO replace them?Quote:
Originally Posted by lowell
he's saying YES replace them.
I intend to replace them but have higher repair priorities such as the transmission whine (now fixed) and then the heater valve. The heater valve may tie in with the coolant loss since I believe the gurgling in the dash is due to an air bubble in the cooling system that redistrubutes itself when I park downhill (air rises to the highest point).