Paint bubbles / Cooling system

[alfafred]

Was Tuesday lookin at two red Murena S, I would really like to own a S. Both cars had lots of nice details and in general OK condition, and both cars had details that had to be repaird.......
Both need paint in the next years, one need change of sylinderhead (new complete follow the car), and one had some watercooling "stuff"... I dont know if there is anything wrong, but..... I understand that new head can be expensive... Both still interesting after wisit. But I must choose the one and buy soon!. I want a new project for the winter.
 


Since I have lots of experience with old alfa romeo`s, but none with Murena 2.2S I ask some questions....
-Watercooling system? Has these cars often trouble with engine cooling/system?
-Is these cars driving with ekstra high pressure in the cooling watertank?
-If a car stored with almost no antifreese, only water can headgasket take damage(corrosion)?
-If sylinder head is defect/water leaqe, in what way to discover this is most common?

-One of the cars have not been used the last years. We had to fill 1,5 l water in the coolant tank to get it to max. I did drive the car approx 15 - 20 min normal road driving, temp on engine was constant and normal. Instrument was on the "white dot" before 90. When parkin the car I let the engine run on idle speed and the temp did go up to 90-93, stabil temp. No fan in the front did start. Normal? Shortly after i did open the cap on reservoar, and it was lots of pressure and air in there, and all water in there did find the shortest way to the floor. Sound normal to you or?... To me it I think two possibilitys, one defective sylinder head gasket/head or lots of air in system because of low water level and that we did fill it up...?



Paint:
One of the cars have in the rear spoiler Osmose. I did make a hole in the bubble (3-4 mm dia) and the fluid inside, acid smell was strong... But also the car panels have bubbles. These are not big, they are small, really small, and in  some sections lots of them. The car have also some larger bubbles, that really look like Osmose. But can also these small bubbles also be osmose?

If its osmose, What have to be done, step by step?

Anyone who can help?  


Fred r

[Jon Weywadt]

------
-Watercooling system? Has these cars often trouble with engine cooling/system?
-Is these cars driving with ekstra high pressure in the cooling watertank?
-If a car stored with almost no antifreese, only water can headgasket take damage(corrosion)?
-If sylinder head is defect/water leaqe, in what way to discover this is most common?

-One of the cars have not been used the last years. We had to fill 1,5 l water in the coolant tank to get it to max.
----
Shortly after i did open the cap on reservoar, and it was lots of pressure and air in there, and all water in there did find the shortest way to the floor. Sound normal to you or?... To me it I think two possibilitys, one defective sylinder head gasket/head or lots of air in system because of low water level and that we did fill it up...?



Paint:
One of the cars have in the rear spoiler Osmose. I did make a hole in the bubble (3-4 mm dia) and the fluid inside, acid smell was strong... But also the car panels have bubbles. These are not big, they are small, really small, and in  some sections lots of them. The car have also some larger bubbles, that really look like Osmose. But can also these small bubbles also be osmose?

If its osmose, What have to be done, step by step?

Anyone who can help?  


Fred r

The biggest difficulty you should have with the Murena cooling system is getting all the air out. If you had to put 1,5 ltr. water in there is a good chance that lots of air is in there. That will push out coolant after driving and getting the coolant hot.
There is a small hose at the bottom of the expansion tank, which is connected to the top of the radiator out front. I take it off and plug the expansion tank while applying suction to the hose until no more air comes out.  The best way is to put the hose into a bottle and applying suction to the bottle. I use a vacuum cleaner for that and hold my hand around the top to get as much vacuum as possible. You should have someone fill the expansion tank while doing this if there is a lot of air in the system.
Near the distributor there is a large coolant hose with a knurled brass screw. Unscrew that until there is no more air coming out.
Doing this should have gotten most of the air out of the system.

But also check the coolant pipes running to the front. Mine were badly corroded and burst during slow rush hour traffic. I have replaced them with stainless steel pipes to make sure it does not happen again. The corrosion is bad under the rubber grommets around the brackets holding the pipes to the bottom of the car.

If the head or gasket is damaged causing you to loose water you may see lots of white vapor from the exhaust. Also, check the oil. Water getting into the oil can turn it into a mayonnaise like substance. And that is BAD.

The bubbles in the paint sounds like the car was not properly primed with a water tight epoxy primer before painting. This is necessary when painting fiberglass. If there are pits in the paint it could be caused by silicone residue.
If you want to repaint the car it should be completely sanded down and properly primed with a high quality epoxy primer. Otherwise you will just have bubbles appear again.

Good luck.

[JL]

Hi Fred

Regarding your paint work, not only will you need to strip down to the fiberglass but you will also need to dry the bodyshell out before you do anything else to it.

Regards
John

[suffolkpete]

Properly maintained, the Murena cooling system is very efficient.  If yours is steady at around 90 deg. there probably isn't much wrong with it, although to be really sure the car needs a good fast run.  There must be a reason why the coolant has leaked away though, could be a radiator leak or the cooling pipes as Jon has said.  The way I get air out of mine is is to blow down the expansion tank filler  with the knurled screw open until water comes out.  I use a small hose wrapped with insulation tape to seal the filler.  There are one or two hazards to trap the unwary when changing cylinder heads, you need to talk to someone with experience of these engines before attempting it.

[roy4matra]

Properly maintained, the Murena cooling system is very efficient.  If yours is steady at around 90 deg. there probably isn't much wrong with it, although to be really sure the car needs a good fast run.  There must be a reason why the coolant has leaked away though, could be a radiator leak or the cooling pipes as Jon has said.

As peter has said, if there has been a loss of coolant that has to be the first concern.  These cars have a sealed cooling system the same as any modern car, and they should never loose *ANY* coolant.  Any loss, no matter how small, shows there is a fault and it must be rectified.

One problem when you get a loss is that air will build up at the top of the radiator and then the fan cut-in switch may not activate as it is no longer submerged in coolant so cannot sense the temperature.

The way I get air out of mine is is to blow down the expansion tank filler with the knurled screw open until water comes out.  I use a small hose wrapped with insulation tape to seal the filler.

The problem with this method is that you will not clear any air from the top of the radiator.  You will bleed the air from the top of the engine area, but the air at the top of the radiator is the first that must be removed.  Jon has detailed the correct method.  You need to suck the air from the top of the radiator via the small hose that connects the top of the radiator to the lower point of the header tank.  To do this, you remove the small hose from the header tank, and then blank off that header tank outlet and fill the tank with coolant.  Then use the small hose to suck the air from the radiator.  Once coolant is flowing from that hose, you can reconnect it to the header tank.

Next run the engine up to temperature so the thermostat opens and then use the bleed screw in the hose coming from the thermostat housing, to bleed any small remaining air from the engine area.

Next check the electric fan cuts in at around 95-98 degrees.  Then take the car for a good run, and at the end let it idle again and re-check the fan cuts in.  If there is a leak, or a head gasket problem or a head is cracked, the air will have built up again in the radiator and the fan is unlikely to work, proving there is still a problem.

If you need to remove the head from a 2.2 engine you MUST back off and lock out the timing chain tensioner first otherwise the bits will drop down and it will be an engine out and strip to get them back!


PLEASE NOTE  Any air at the top of the radiator will be almost impossible to remove any other way than described since air will not want to flow downwards to the radiator bottom hose to travel back to the engine, where it could eventually be bled from the bleed screw in the top hose.  It cannot come back to the engine from the radiator top hose since the water flow is in the wrong direction.

Roy

[alfafred]

THANKS to you all!.
Important for me to read what you can tell me about these cars! I am totally without any experience about them, but I have dreamed about a Murens since, I guess 1982.
 

I have brougt this car. Only two owners, dokumented history and only 60500 km. Everything on the car is original, only exhaust muffler have been changed some years ago. The rest is..... original....

I will spend two years on this project, and the car will be ready summer of 2014, when its 30 years old. Have also sent a mail to th DK club and I want to join the club. 


Cheers, this evening I`ll take a couple of Carlsberg Sort Guld and a Braastad XO superior to celebrate.....

    Yes, I am happy.....

[Jon Weywadt]

Cheers, this evening I`ll take a couple of Carlsberg Sort Guld and a Braastad XO superior to celebrate.....

    Yes, I am happy.....

Wait 24 hours after your celebration before driving your car.