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Discussion Starter #1
Hi Ken,

Honestly your type


Hi Ken,

Honestly your type problem is VERY difficult to solve in this environment. There are just too many variables.

Even the best techs in the world are forced to service parts that may or may not help, such as the flushing of a radiator. Because we can't see inside the radiator or even see the fins, there is really no way of ascertaining condition without pulling it out and looking at it, at which point one might as well send it off to be fully cleaned and resoldered. I do run very careful Temp Drop tests on radiators I suspect of being an issue. A good radiator should shed about 25-35 degrees across the core from inlet to outlet, w/fans running, AC off. Occasionally I have seen a little less drop that caused no apparent issues, but my best guess is about 20 degrees is probaly the minimum acceptable.

I would say definately install a new radiator cap. Cheap insurance. And of course as long lasting and durable as the thermostats are they do eventually give out. Again with the t-stats there is no way to guess condition and no way to know why one may last 20 yrs and another only 10 yrs.

You say you bleed the radiator before every drive, do you find air every time and if so how much?

Regards, JRV
 
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Discussion Starter #2
Thanks for the post JRV.

I


Thanks for the post JRV.

I will buy a new thermostat and radiator cap ASAP. It cannot hurt to have new ones, or at least a spare.

One question I have is "if" my radiator is clogged and needs to be re-corded, would that cause the oil to run hot too?

As to bleeding my radiator, I usually have to wait about 5-10 seconds after each drive for all of the air to escape. In fact, even if the car sits for a month or two unused I still have to let some air out of the system. Is this normal?

Thanks.
Ken
 
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Discussion Starter #3
Hi Ken,

Alhough the solutio


Hi Ken,

Alhough the solution to your problem may take a bit to get to the answers, it's a great question that I believe many cars suffer from, to some degree. Although my currert...and long-time favorite ride is my BB, I have owned both a 308QV and 328, so I'm familiar with the collings systems in great detail.

To answer your question about the rising oil temperature...Yes, it happens if there's a weakness in the cooling system, or in the oil "cooling system function..." So, to see a rise in both oil and water temperatures is not uncommon.

You may be aware that I spent a long time tracking down why my BB ran hot whenever it got into even mild traffic, or the ambient temperature was over 70F.

In my opinion, the cooling systems, even when working properly are borderline effective. So, any deterioration, or components out of specs...can have noticeable effects on those engine temperatures.

Starting at the bottom...and working up.

1-Drain and fill the transaxle.
2-Dain and fill the engine oil
3-Remove and re-core/replace the radiator
4-Replace/verify therostat for correct oppening temperature.
5-Remove waterpump and verify the waterpump impeller to housing clearance. This can have a hugh effect on the pumps cooling/pumping efficiency. This is not your causual rebuild issue...
6-Verify that the thermo-fan switch turns on at 79C, or lower. Replace with low-temp VW/Porsche 924 switch.
7-Update if you wish to the later 328 5-blade fans...and verify the proper blade rotation.
8-Inspect cooling system hoses for "cold-seep"...evidence of green/white crud around hose connections. This could be your "source" of air seepage.
9-Verify spark plugs for proper heat range.
10-Verify ignition advance is not stuck/fixed.
11-Verify mixture strength (leaness could cause higher engine temps, if the car is driven hard)

Granted, this is a very comprehensive list but....these are all the steps I took, and ended up with a very cool (running) BB. Take no shortcuts, and I'm sure you'll be pleased with the outcome.

Best of luck!

Regards,
David
 
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Discussion Starter #4
Thanks Dave for the great repl

Thanks Dave for the great reply.

Why should I drain and refill the transaxle in terms of my problem? I currently have whale oil in there and my mechanic told me not to change it now. He said that the whale oil can remain in there for years with no problems since it's a closed system. Also, should I still use the whale oil, or do you recommend another oil? I normally use Agip oils.

As to the "cold-seep" issue, I did notice that the sending unit on the bottom of the radiator is corroded with a green/white crud. Perhaps I have a leak here. I will also check the other hoses again, but I do not recall seeing any crud on them.

Thanks again.
Ken
 
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Discussion Starter #5
Morning Ken,

While I agree


Morning Ken,

While I agree that the transaxle is more, or less a sealed unit (there is a vent to the atmosphere), my reasoning for changing it was two-fold.

1-It may be low on oil...which in turn will cause higher than normal gearbox temperatures. In that the engine sits on top of the gearbox...this situation can also drive up engine temperatures.

2-Gearbox oils, no matter the type do break down over time, as well as miles. Airation can and does occur, again resulting in higher than normal gearbox oil temperatures....

These above reasons are why I stated "I like to start at the bottom...and work up..."

Oil preferences are about as subjective as what's makes a woman good looking...There's no substitute for quality products. Although I don't use Agip products in my BB, I feel that they clearly fit into the "quality" category. Personally, I use Mobil 1 in the engine...and Royal Purple in the gearbox.

The corrosion you refer to is evidence of "cold seepage" and should be addressed. Corrosion, in itself, on the sending unit, can act as an isulator or soft, and cause the fan to turn on at a higher than specified temperature. Simple, cheap fix, for sure.

This "air seepage" mystery that Ferrari seem to have, more oftem than not, is somewhat annoying...though I personally don't feel is of great concern. The overflow cap are truly junk, and have a useful life of maybe a year or so, before they leak at the seal...

I wish I could tell you that it was one specific thing that fixed my cooling issues with the BB...None of the problems I had were major....but all the little issues did add up to elevated engine temperatures.

Regards,
David
 
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Discussion Starter #6
Ken,
My mechanic pulled the r


Ken,
My mechanic pulled the radiator on my 328 during a major and had it "rodded out" which apparently entails cutting the bottom off, and running a long round brush through the tubes in the core. They cleaned out a lot of crud. My car was not reading all that high, but was done as a precautionary measure. I think this is commonly needed on all these 308/328/Mondials as they are now "old" cars, and need the radiators cleaned out. Shoot, even the newest 328 is a 15 yo car now! I doubt a recore is warranted, just have the stock one cleaned out. This is a cheap repair, probably $400 or $500. Take Dave's advice and spend $15 on the VW thermo switch. They are available in two settings, stock and 10 degree lower value than the stock one. I'm still using the stock Ferrari one, but if I ever need a replacement, that would be the one to get.

Here's a link to the source....Automotive Performance Systems (although any VW shop should have them) http://snurl.com/3ayq
 
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Discussion Starter #7
Thanks David and Dave. Your i

Thanks David and Dave. Your input is always appreciated.

Ken
 
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Discussion Starter #8
Dave,

thanks for making the


Dave,

thanks for making the OLD car point again. Even though most of these cars have low mileage and in many cases look almost new (on the outside), truly 15-20+ yrs is considered getting old in car terms. What speaks mightily of the product itself in terms of their ability to hold up, also tends to make us forget that on a lot of the parts the clock never stopped ticking from day one.

On the air issue:

The first problem with the cooling system is caused by what's known as cavitation by the water pump blades, as it spins air bubbles are churned out of suspension and into bubbles, the same thing that occurs on a boat propeller for example. These 'bubbles' are then carried forward and trapped at the top of the radiator. Every time the WP spins it creates bubbles. Another source of air (bubbles) in the cooling systems sometimes can come from the loss of complete seal between the head gaskits and block/head sealing surfaces that occurs because of corrosion/electrolysis at the points where the water jackets are closest to the head studs. I hate bringing up that point because it tends to scare people which I try to avoid in most of my writings.

Here in Texas where the summer heat is brutal, I'm a firm believer in the Low Temp Fan Switches Dave H. mentions. Along with Watter Wetter. And as David F. mentioned these cooling systems are on the edge of cooling ability even from new. Which means that all the parts of the system play heavily into the overall ability to keep the engine cool.

All the above suggestions play a big part in bringing cooling temps back in line. Generally it is not one thing, but a combination of many things as mentioned that prevents simple answers and simple solutions for what are often complicated problems.

Regards, JRV
 
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Discussion Starter #9
I called Algar today and order

I called Algar today and ordered a new radiator cap (did not ask for the price and do not want to know!). Only after I placed the order did I realize that my cap is rated at 0.9 bar. The new cap is rated at 1.1 bar. Algar said that the Ferrari no longer makes the 0.9 bar cap and that the 1.1 bar cap is the replacement part. Is the higher rated cap going to cause a problem with my already hot running car?

Also, what is temp that the OEM thermostat opens for a 308QV?

Thanks.
Ken
 
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Discussion Starter #10
Hi Ken,

the 1,1 bar cap wil


Hi Ken,

the 1,1 bar cap will help not hurt. 1 Bar is 14.7lbs.

The engine t-stat opens @ 78 centigrade (approx. 180F), the fan switch on the radiator turns on @ 87C (approx. 192F).

Regards, JRV
 
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Discussion Starter #11
Here is a picture of the fan s

Here is a picture of the fan switch (I think) that is full of white/green crud that may be the source of my "cold seep" and air in the system. What do you guys think? (sorry for the bad picture, lighting was not good) Is the build up of crud on the fan switch bad? I will be ordering a new one this week.

Ken
 
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Discussion Starter #13
Only bad if the corrosion is a

Only bad if the corrosion is affecting the electrical conductivity of the connections on the back. After all these years, worth replacing regardless. It should come with a new gasket. If not, get one.

I think the greenish color is just the reaction of the coolant with the brass construction of the switch.
 
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