Stefce

Hi.. All
I have 2 specific problems and i really dont know what and how to search for them
1. No overheat problem(fans kick in and out at regulat temps as stock would) but i get coolant blowing by the the cap hose that vents excess pressure or coolant to the atmosphere this usualy happend when i drive the car and i stop ..park it and let it sit..usualy fan works 1-5 seconds after i turn it off which indicates that its normal temps.. But after a while it starts to leak from the cap overflow hose..
i tried other cap and still the same..
With this i loose 1 to 3 quarts of coolant and than i get air in the system and not enough cooling.. I refill it and after 10- 20 days the same
what would cause this.. ?i guess engine is hot and with it not working it overheats the coolant and it starts to build pressure and makes my coolant leak due to pressure releaf..
no white smoke or coolant smell from the exhaust.
2. 2nd problem i get is that after city driving (stop and go)or few wot's and car is hot.. I turn it off and if i start it up next 10..15 minutes..or earlyer..i get the oil light come on.. And sits during the whole drive.. If i let it cool it doesnt show up on next start.. Lets say 25 min or more..
if i keep on driving the car from first warm up ..2 ..3 hrs .. Hot..spirited drive.. No oil light.. Just after i start it.. After a hot drive..never during a drive the oil light comes on..

Mods i done
No cat,catback, Sohn adapter and premix in fuel, no oil consumption and oil seems clean not black..

Loki

iTrader: (1)

You're not losing 1-3 liters of coolant through the overflow, if you're losing that much it's exiting elsewhere. Simply because it's an overflow/expansion tank, if you're a quart low there's nothing in it.

I would do a block test to check for exhaust gases in the coolant to confirm/exclude coolant seal failure.

Oil level going off when hot is a somewhat common issue on older models, especially when run hard. As long as you're sure the oil level is OK, it's a minor nuisance. Repairing it means removing the oil pan and potentially replacing it with a later version.

Stefce

Oil light ok..i guess it wasnt a problem since it goes away sometimes and oil level is good..no oil consumption now with Sohn...and oil is clean..and car is doing fine hasnt failed

About the coolant loosing..i see that the coolant is lost from the hose on the tank since the radiator shroud is all with coolant from the hose..hose is 10cm or 4 inches long..it above the shroud.. And i see the coolant..all over the shroud
now i dont get it why it does this.. When the car is shut off it starts to probaby build pressure and makes my cap loose coolant..this doesnt happen when car is working or at least if it happens it just a little..
I had the coolant leak from the cap massivly when it was too hot outside...and i drove the car with ac and wot.. But i detetced it.. Later why..
first only one fan was working..other wasnt.. Or it was from time to time.. I couldnt understand why.. Tested the xonnextions 12v comes to the fan and doesnt work.. I guessed it was something wrong with it..
i decided to upgrade bith fans with Spal fans..i took the radiator off, cut the plastic to take the old fans off and installed new spal fans on the openings of the old fan place..
what an upgrade..now with 1 fan it manages the heat on a normal warm day..
But one fan was kicking in soetimes and soetimes not.. Like before.. Tested my connections and there was 12v.. Positive side with ground from the chassie or the battery.. But no ground on the connector.. Than i gave the connector ground and the fan works.. It turns out that the ground was bad and i had to ground the fan somewhere else..now its all ok.. Even on hot hot days..
But now the coolant leaks even if the fan isnt required.. From the hose..

What i should do next is put a pressure gauge inline the hose next to the ecu to check if pressure is rising too high and makes my cap loose coolant..
about the exhaust seal..may it be possible i dont get leaks in the exhaust from coolant (would smoke and smell like burnt coolant) but get leaks in the cooling system from the pressure of the exuast and makes my sistem with higher pressure than normal?
its a 2006r rx8 from germany.. I see black silicone on the housings.. I guess somebody had opened the motor before but i have no info on it.. On how and why,And i get little oil leak from the front crank pulley ...i changed the seal but still leaks..a little.. since the oil level doesnt change

Loki

iTrader: (1)

Depending on where on the engine you're seeing that silicone, it could be cause for concern that someone didn't know how to close it properly.

Yep, exhaust leak to the coolant circuit is what I'm thinking. This is what a block test checks, it's a simple DIY procedure. Adding pressure gauges and stuff sounds complicated. There's an even simpler visual test: start the car with the engine cold and the rad cap off. As the car warms up watch for bubbles coming up into the overflow. Those bubbles, if present, are exhaust.

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Stefce

Good idea..i will do that first..check for bubbles
thing is i bought a 1.3bar cap thats from ebay that is compatible with our cap but i worry if its a real 1.3bar.. Since its the same as the 0.9 oem cap..
silicone is between the rotors and plates