328 Oil running hot with gauge going up and down....help!!

I just had some coolant hoses changed and new coolant added.
The level was good but later after the venting of the radiator and cabin heat exchangers the coolant was too low.
The temperature gauge fluctuated between 90-120C.
Coolant should be 6 cm from the top of the opening, the manual says.

Also confusing with the Coolant Temp gauge just below Oil Pressure gauge.

 

Top up the coolant. The level went down because coolant had to replace the air that was vented, the gauge was fluctuating because of the air in the system. You don’t have a problem unless you’re going through this bleed/fill cycle repeatedly.

 

I have the EXACT same issue with H2O temp fluctuations. Turns out a water pump leak is allowing air into the cooling system. (Leaks under pressure at operating temp, then sucks air back in under vacuum when cooled; all through one of the weep holes in the pump.) I'm in the process right now of changing out the pump. While I'm at it, I'll swap in a new thermostat and doing a cooling system flush. I already have new coolant hoses, so am good there. I'll keep you posted if this helps.

BTW... Any thoughts out there on Evan's Coolant? I like the idea of it being non-corrosive, pump won't cavitate, doesn't boil (at normal op temps), lifetime coolant (1 and done), runs at lower pressure, ... Seems like if it's good enough for Leno's collection, why not?

 

The most rotten hose was the one from the bottom of the radiator up to the heater box.
To change it you need to take out the brake Booster together with the master cylinder.

 

The October 88 parts book TAV. 34 is titled CLUTCH HYDRAULIC SYSTEM- Cars with Anti Skid system. It in reality shows the hydraulics for the ABS system.
That mismarked page is what started the wives tale some 328s have hydraulic clutches.
Kieth is a friend so I hate to say this but that book has a good deal of misinformation. Mostly in the form of misleading pictures.

 

I have replaced that hose many times and never needed to remove the booster. Its not easy but easier and quicker than pulling the booster.

 

Agree but really hard on hands