It's back on the road

[biffa75]

Hi folks,

Just a quick thanks to sd1too (Simon) and arctic and to others who have helped me with advice and parts and pictures I've the past few weeks while trying to fix our 75 V6.

Today we got the tyres done and changed the aux belt idler pulley. For those who know about my coolant bleeding woes. I still aren't certain wether I have been able to bleed the system completely but I have been able to drive it and put some miles on it. Hopefully a drive round etc may help move the airlock.
It feels much better on new tyres.
I did also run the diagnostics while driving to show the coolant temp.
Drive along smaller A roads in 0.5 to 1°c so fairly cold outside temperatures the engine coolant temp was showing between 83-85°c mainly between 30-50mph with occasional snow flurries. (These temperatures around normal?)

Thanks again
Rob

[SD1too]

Originally Posted by biffa75

Just a quick thanks to sd1too (Simon) and arctic and to others who have helped me ...

Thank you Rob, that's very kind of you.

As for the temperature, I'm not sure. Keep it under observation; the weather's supposed to be getting a bit warmer next week.

Simon

[biffa75]

Not a problem Simon, but I may need to pick your brains in the future 😅.

I wasn't overly concerned as I know there's coolant in there. I'll keep an eye on levels and temps. What would normal temperature be? I'm sure the stat opens at 82°c.

Thanks
Rob

[SD1too]

Originally Posted by biffa75

What would normal temperature be? I'm sure the stat opens at 82°c.

I've always thought that it's just above the thermostat's opening temperature which is 88°c despite what it says on the plastic housing! I'll try to remember to check mine when I next use the 75 on a freezing cold day.

Simon

[biffa75]

Okay so that could also explain low mpg despite really steady driving (around 26mpg). As effectively it could still be on choke?.

If the coolant system needs another bleed attempt, would you recommend looking towards a blocked oil cooler?

Thanks
Rob

[vitesse]

My normal running temperature (2.5 V6) is around 94 degs and we haven't seen the temperature over zero for the past 2 weeks.

Regards

[biffa75]

Update:
Made another attempt to bleed the coolant system today. Went round and had a good look, definitely no leaks anywhere.

So raised the front of the car up enough to make the expansion tank the highest point even when bolt back the front panel. (In a bid to make the heater matrix the lower point to hopefully rid the matrix of air).

Here's what I did with the front of the car raised up:

Raised the expansion tank, filled it the bottom of the neck opening.

Removed the bleed screw so coolant came out under some force due to the expansion tank being raised.

Fitted bleed screw

Filled the tank to level with the bottom of the neck.

Bolted the expansion tank back down

Entered diagnostic mode for the temperature readout.

Started engine with coolant cap off and kept the revs at 1500rpm occasionally raising to 2500.

Coolant level began to overflow a few minutes after started and continued to flow out regardless of the rpm. Once the readout hit 80°c. Fitted coolant cap.

Continued to maintain 1500rpm until 100°c was reached and radiator fan kicked in.

Returned to idle speed and temp dropped from 100°c to 90°c and began to steadily climb but then turned off the engine.

Allowed to cool for a short while with bonnet open.

On return I found the top hose that runs along the top of the radiator had collapsed (under vacuum) as the coolant tank cap was removed, air rushed in and the hose went back to normal.

Started again gave a few revs (coolant began to rise slightly again). Cap fitted again before overflow began out of the neck.

Now back down on level ground. I could hear a faint trickle behind the dashboard and lasted maybe a second or two so appears better than before.

I'm hoping raising the front of the car and trying may have sorted it. Need to take it for a drive and see what the temperature comes back with.

Rob

[SD1too]

Originally Posted by biffa75

... I found the top hose that runs along the top of the radiator had collapsed (under vacuum) ...

That shouldn't happen Rob. I'd suspect a faulty expansion tank cap.

Simon

[biffa75]

Yeah having now read your comment it doesn't seem right. Only issue is.. it's a brand new cap. Reckon it's worth fitting the old cap?

[stevestrat]

Originally Posted by biffa75

Only issue is.. it's a brand new cap. Reckon it's worth fitting the old cap?

Where did you get it? Few years ago I bought a supposedly genuine one on the Ebay, it was worse than the one it was replacing! Got one from Rimmers, that was fine.