General Deeper sump question

[timgarman]

Hi Folks

My 500 still has a tendency to spray the engine bay with oil occasionally. I always felt the culprit was the dipstick not sitting snuggly enough in the hole.

2 questions regarding the dipstick.

Firstly, I have the 3.5L sump fitted. If I still have the original dipstick and fill up to between the two marks will that mean I'm over filling the sump and causing oil to spray out (somewhere)? Could this be the cause and should I have a longer dipstick (oo-er Mrs)?

Secondly, and off on a tangent, should the car stall when idling if the dipstick is removed?

I'd really like to resolve the oil spraying issue so many thanks in advance and a Happy New Year.

Tim

 

[gordinir8]

After my 3.5 litter installation i discovered that original dipstick marks where not true so i had to calibrate it. If you suspect your seal is not good go for a new dipstick. Here is what i done to mine to secure it since i have reed that they some times pop out.
Thomas
https://www.fiatforum.com/500-classic/463453-sliding-dipstick-rubber.html

 

[the hobbler]

Morning Tim;
First of all, all the best to you in the New year. Regarding your oil spraying question---I have a 3.5ltr sump om my 126 based engine, and do not suffer 'oil spray'. (a) what dipstick are you using? and, (b) have you checked that the breather on the rocker-cover is not blocked?
Regarding (a)---I have a standard 126 dipstick, which is the type with the long rubber holder/seal on the stem of the dipstick, rather than the 500 type which is held in place by the 'bent bit' of the dipstick. Being that the whole point of the deeper sump is to carry more oil (which helps cool the engine), bringing the oil level to the top mark on the dipstick will NOT be overfilling it--you are still only coming up to the same level vis-a-vie the crankshaft/top of sump as in a standard sump.
Regarding (b)---If the breather is blocked, this will cause pressure to build up in the crankcase, which has to find a way out--the dipstick orifice is 'the easiest way out'.
As to why the engine should cut out when the dipstick is removed, off the top of my head, I can't think of a reason--yet.

 

[lazylobster]

Just a thought, when you remove the dipstick are you shorting it against the distributor body?

Rob

 

[timgarman]

Hi Tom and Thomas

Thanks for replies. I've attached a photo of my dipstick, quite different to yours Thomas, but possibly with the same issue gripping the hole.

Is the breather tube the one that goes from the top of the rocker to the front of the carb (FZD)?

Next time it happens I'll take a photo.

Tim

 

[fiat500]

Hi Tim, my 499 engine had that same dipstick and someone recommended tweaking the bent bits which keep it in place. I'm not sure there's any need to remove it when the engine is running ? but for it then to stall is very odd.
I'm not familiar with those deeper sumps but I do know there are baffle-plates available, which will subdue any oil surge on cornering etc. Not sure if they're recommend for yours. Also worth thinking about oil viscosity. I've gone for a thinner oil for winter and when the engine gets hot I can smell the raw oil vapour even without obvious leakage.
With any oil leak on this engine, the air-flow from the fan can send a mist anywhere and be quite misleading about the source.

 

[timgarman]

Thanks Peter, I'll try adjusting those metal arms on the dipstick. Also interesting re the fan. Although it has looked more like an explosive oil leak, more recently it has the look of a fine mist. I think the baffle-plates are more often recommended for the 4L sump. Doesn't the sump moulding have some fins that reduce this anyway?

Rob, I will make sure I avoid the distributor when removing dipstick.