[Aleksej]

Hello everybody,

Recently I got Skyline R33 GTST and already fixed common issues like a speedo, suspension ball joints, HICAS joints, air conditioner actuator etc.

At the moment I am having problem of leaking oil from the oil cooler. To fix that I already got new seals and O-rings, had already read service manual for my engine RB25DET.

Service manual says I need to remove only oil cooler ASSY including oil filter bracket and some coolant hoses.

But I steel not sure if it can be done in this way, because there is no space, all parts are very close to each other. Worst case I have to remove Inlet manifold.

Does anyone know how to remove oil cooler? It is necessary to remove Inlet manifold?

I need to fix it soon, any help would be great.

Thanks guys

Aleksej

 

[sparkso]

Can be done with manifold on but it's quite awkward, you need a decent socket set with various adapter bars to get at it properly, probably easier done from underneath

 

[Aleksej]

Thanks for your fast answer. Several sockets are not the problem, I just try to get it out.

What is the best way?
to separate oil cooler and oil filter bracket (1 Bolt)
or
to separate oil filter bracket incl. oil cooler and cylinder block (4 Bolts)

 

[sparkso]

If I remember it took a bit of force to separate the cooler from the adapter so it will probably be easier to take the whole assembly out first, but you will need a new gasket for it before you bolt it back to the block again

 

[Aleksej]

Hello guys, on the weekend I replaced oil cooler. It was pretty simple job, it took me about 2 hour.

I done it in following order:
- Remove the under cover
- Drain coolant from the radiator
- Drain engine oil
- Remove oil filter
- Remove oil pressure sensor
- Remove water hoses on the oil cooler(be careful of dropping coolant, about 0,5L)
- From underneath unscrew oil cooler from oil filter bracket (you need 3/8 ratchet and 17mm socket)

I also replaced the Thermostat. Engine won't reach operating temperature or only reach in case of full load. The reason for this behavior was rubber seal on thermostat which is damaged/ cracked. If temperature was low, the thermostat doesn’t closed properly.

At the moment there are no oil leaks but the engine lousing coolant. Coolant hoses and thermostat housing are 100% leak proof. It seems if the water pump is leaking.

Any idea why is the water pump leaking?
- Does the coolant pressure increased if thermostat is closed?
- Is new coolant incompatible with old coolant?

 

[DRIVE_Chris]

on most cars if the water pump is leaking, it's usually a sign that the water pump has failed, it's suggested to change the water pump on these cars whenever you do the timing belt so perhaps it has failed. it's a fairly simple task to replace if that is the culprit

 

[Aleksej]

on most cars if the water pump is leaking, it's usually a sign that the water pump has failed, it's suggested to change the water pump on these cars whenever you do the timing belt so perhaps it has failed. it's a fairly simple task to replace if that is the culprit

Sure, soon I am going to replace timing belt because it is already 10 years old and install new water pump.

I was surprised about leaking water pump after replacing thermostat and oil cooler.

I inspect the engine for any leaks before maintain, the water pump was leak proof. After maintain I also inspect all parts which need to be removed during maintain (hoses, housings and flanges), all of them are good except the water pump.

I am just curious to know, what caused this leak?

First thing I can imagine, is the pressure in small cooling circuit, if the engine temperature is lower than 78°C. Maybe before replacing thermostat was shaft seal already weak, but small and large cooling circuit was not properly separate by damaged thermostat. In this case the pressure built by water pump up escapes through thermostat to large cooling circuit. New thermostat keeps water in small circuit, the pressure has increased and escapes through the shaft seal on the pump.

OR

New coolant isn’t compatible with old coolant and just destroyed shaft seal.

 

[Aleksej]

Sure, soon I am going to replace timing belt because it is already 10 years old and install new water pump.

I was surprised about leaking water pump after replacing thermostat and oil cooler.

I inspect the engine for any leaks before maintain, the water pump was leak proof. After maintain I also inspect all parts which need to be removed during maintain (hoses, housings and flanges), all of them are good except the water pump.

I am just curious to know, what caused this leak?

First thing I can imagine, is the pressure in small cooling circuit, if the engine temperature is lower than 78°C. Maybe before replacing thermostat was shaft seal already weak, but small and large cooling circuit was not properly separate by damaged thermostat. In this case the pressure built by water pump up escapes through thermostat to large cooling circuit. New thermostat keeps water in small circuit, the pressure has increased and escapes through the shaft seal on the pump.

OR

New coolant isn’t compatible with old coolant and just destroyed shaft seal.

 

[Aleksej]

Hello guys,

This week I replaced timing belt and water pump. Coolant leak was definitely on water pump. Now seems the engine to be leak proof.

By replacing the timing belt most helpful tool I used is the crankshaft pulley wrench. My skyline has automatic transmission from this reason there is no way to stop the crankshaft by transmission also there is no way to get Nissan special tool to stop flywheel. So I decided to design crankshaft pulley wrench.



It cost me about 30€, but it make tightening and unscrew crank pulley so easy. There are 2 parts from 15mm steel bolted by M6x30mm together. So if somebody need this tool, DXF are available.