205 coolant replacement

[Jared]

Hi all, when replacing the coolant on a 205 (Si) I’m following along the Haynes manual and it mentions two things:

1. Cylinder block drain plug - I couldn’t find it, can anyone send me a photo please?
2. Bleed screws - I could only find one at the heater matrix hose, are there any others

Side note I also noticed oil at the back of the block - looks like oil from the rocker cover? But I also noticed white smoke out of the exhaust so maybe a head gasket issue?

 

[Geopug2]

It’s been a while since I had a 205 but from memory i think the only bleed screw was on the heater matrix hose. ( my current C4 also has one on the thermostat housing but I don’t remember one there on the 205). I didn’t find a cylinder block drain plug either. I drained the coolant by undoing the bottom radiator hose.
i refilled through the radiator cap, ran the engine to get some air bubbles out then put the cap on before it got too hot and then topped up the expansion bottle. It may take some time to get all the air out but just check it each day when engine is cold to see if you need to add more coolant to the expansion bottle.
normally if the head gasket has gone, the oil under the oil filler cap will be a milky yellow colour. I am no mechanic, but that has been my experience.

 

[Jared]

It’s been a while since I had a 205 but from memory i think the only bleed screw was on the heater matrix hose. ( my current C4 also has one on the thermostat housing but I don’t remember one there on the 205). I didn’t find a cylinder block drain plug either. I drained the coolant by undoing the bottom radiator hose.
i refilled through the radiator cap, ran the engine to get some air bubbles out then put the cap on before it got too hot and then topped up the expansion bottle. It may take some time to get all the air out but just check it each day when engine is cold to see if you need to add more coolant to the expansion bottle.
normally if the head gasket has gone, the oil under the oil filler cap will be a milky yellow colour. I am no mechanic, but that has been my experience.

Not under but in the neck of the oil filler it did look a little milky

 

[matara]

If you have been doing a lot of short cold starts and the engine hasn't run for very long then it could be a build up of condensation. You can get a head gasket test kit that has a glass tube where the colour changes if exhaust gases are present in the coolant.

https://www.amazon.com.au/RELD-Gasket-Tester-Combustion-Detector/dp/B07RS3N98V

The oil on the back of the rocker could just be the rocker gasket. Maybe start by replacing that first. How are things progressing with the little red Si?

 

[run205]

if you still have the orig rad, there should be a drain screw (M14 spanner) on the Left end, faces to rear of radiator
and if you remove the bottom hose at right front that will drain any remaining coolant

the oil leak looks as you suspect more like a camcover leak
they get old and brittle so a new one might be the go

 

[Jared]

If you have been doing a lot of short cold starts and the engine hasn't run for very long then it could be a build up of condensation. You can get a head gasket test kit that has a glass tube where the colour changes if exhaust gases are present in the coolant.

https://www.amazon.com.au/RELD-Gasket-Tester-Combustion-Detector/dp/B07RS3N98V

The oil on the back of the rocker could just be the rocker gasket. Maybe start by replacing that first. How are things progressing with the little red Si?

Yea progressing well, still a few things on the to-do list with the biggest being a refurb of the rear beam but for now I’m really enjoying driving it - such a fun little car!

 

[Jared]

if you still have the orig rad, there should be a drain screw (M14 spanner) on the Left end, faces to rear of radiator
and if you remove the bottom hose at right front that will drain any remaining coolant

the oil leak looks as you suspect more like a camcover leak
they get old and brittle so a new one might be the go

Ah ok, well I think I did it right then. I was surprised how much additional crud came out when I opened up the bleed screw on the heater pipe.

I’ll give the cam cover a shot first hopefully that solves it - do you know if the permaseal brand you get from Supercheap are ok or best to get OEM from someone like EAI?

 

[GRAHAM WALLIS]

The important bleed point is near where the radiator hose goes onto the thermostat housing. No block draining point that I know of.

 

[run205]

I’ll give the cam cover a shot first hopefully that solves it - do you know if the permaseal brand you get from Supercheap are ok or best to get OEM from someone like EAI?

haven't tried anything from supercheap cept maybe coolant, awful place
I'd get the EAI camcover seal if you can

also, obvious I know but careful not to overtorque the little rad drain screw
fairly easy as the rad is copper so will bend and crack if you're too physical
inherited one from a prev owner that did that, solder and a pressure test should see it right
great little radiators

 

[Jared]

haven't tried anything from supercheap cept maybe coolant, awful place
I'd get the EAI camcover seal if you can

also, obvious I know but careful not to overtorque the little rad drain screw
fairly easy as the rad is copper so will bend and crack if you're too physical
inherited one from a prev owner that did that, solder and a pressure test should see it right
great little radiators

Haha that is exactly what happened when I first got the car! Pretty sure there was a thread with people telling me how to solder it back. I was a lot more careful this time

 

[Jared]

The important bleed point is near where the radiator hose goes onto the thermostat housing. No block draining point that I know of.

This one?

 

[run205]

jared, I think its the one up left of your blue circle
haven't had an XU5 for a while but that little black coolant hose has a bleed point where it joins the block
its that stubby little metal pipe, usually its got a bullet hex head screw
quite often when owners don't replace (or shocker - sometimes dont even use) coolant it becomes blocked/corroded
and the screw freezes in or snaps off etc etc
avoid all that and many other problems by replacing coolant every few years

 

[GRAHAM WALLIS]

See my comments on the photo itself.

 

[Jared]

See my comments on the photo itself.

Hi Graham, did you forget to attach the photo?

 

[flock]

Looks like you're missing the brass screw. Or perhaps it broke off (as they do) and is blocked up anyway.

You have a lot of oil above, and since it doesn't have a distributor the most likely cause is a cam cover gasket, but could also be the gasket on the thermostat housing (which could also be seeping coolant into your oil) or even the oil coming up the dipstick from blowby.

 

[GRAHAM WALLIS]

Hi Graham, did you forget to attach the photo?

On your photo.

 

[GRAHAM WALLIS]

if you still have the orig rad, there should be a drain screw (M14 spanner) on the Left end, faces to rear of radiator
and if you remove the bottom hose at right front that will drain any remaining coolant

the oil leak looks as you suspect more like a camcover leak
they get old and brittle so a new one might be the go

I just replaced my cam cover seal. Original 30 year old one for sure, had to chisel it off in pieces.

 

[Jared]

View attachment 227939

Looks like you're missing the brass screw. Or perhaps it broke off (as they do) and is blocked up anyway.

You have a lot of oil above, and since it doesn't have a distributor the most likely cause is a cam cover gasket, but could also be the gasket on the thermostat housing (which could also be seeping coolant into your oil) or even the oil coming up the dipstick from blowby.

Interesting. When I pulled off the thermostat housing there wasn’t a gasket. Looks like I’ve got a couple of gaskets to replace, thanks all

 

[Jared]

I just replaced my cam cover seal. Original 30 year old one for sure, had to chisel it off in pieces.

Thanks Graham, did you order through EAI or elsewhere, do you recall the part number please?

 

[flock]

Interesting. When I pulled off the thermostat housing there wasn’t a gasket. Looks like I’ve got a couple of gaskets to replace, thanks all

Not the thermostat cover with the radiator hose. That just seals via the thermostat seal/orings.
Where the thermostat is housed and the ignition coil is mounted is a separable casting like so:

Also has all the temperature sensors. Unlikely to be leaking if it has never been cracked open though.