'76 Dolomite 1850HL

[captain_70s]

Well, the car still lives and is earning it's keep quite nicely. Actually it's earning it's keep so well I'm hoping to rid myself of the Corsa by summer and use the money I'd save to keep the 1850 as a daily driver. It really is a staggeringly capable car for such an old design.

It's easy to drive, keeps up with modern traffic, is economical if you resist the urge to floor it, can happily carry 4 people yet is compact and it feels far more connected than my modern cars regards driving feel.

It's also easy to park with pin point accuracy, as I found out squeezing between my Mum's Mini and some double yellow lines.




That's a rain drop's width, I'd like to see somebody do that in a modern car! (I was actually a bit further back, but when I let off the foot brake the car eased forwards a bit on to the hand brake/gears).

It also saw me through a sudden and entirely unexpected blizzard!




30mph as visibility could be measured in inches and stopping every 5 miles or so to clear the headlights, progress was steady if not fast. Much more predictable than the Corsa regards handling, and also better overall grip in snow! Probably due to the Corsa's wide low profile tyres which are hopeless at this time of year.

It seems rather rare for me to report good news when it comes to the Dollys, but this car has done me rather proud over the last few months, so hopefully when it decides to fall to bits I can look back and use this as inspiration to fix it!

[Rusty Toaster]

What a cool car. Good to know she's back on the road and earning her keep.

[Nick C]

Good to see you're feeling happier about it now

[lazeruspete]

wish I could parallel park that well!

[Edin Dundee]

I am so glad you've got the old girl back on the road and enjoying the drive. 1850s really are great cars.

[Jon Tilson]

The thing about driving dolomites or any rwd is that engine braking is NOT your freind.


Hence when descending any hill engine braking via the rear diff can and will cause loss of control....I know this from biter experience.


So neutral and cadence braking with the footbrake only is the way to go...

You can of course do handbrake turns if you have the space....quite fun to use for reverse parking in a cul de cac...

Jonners

[captain_70s]

Okay the greatest fear on this for you will be coolant loss.

If warm air EVER stops coming out of the central heater vent or any sudden upward movement of the temp guage stop immediately.

Well, driving in to Aberdeen the other day the temperature started to rise while I was in slow traffic, I found somewhere to stop just as it hit boiling point and let it cool off. I had the car recovered home and had a better look yesterday. I took out the thermostat and dropped it in some boiling water and it did sod all, so I assumed that was the 'stat at fault. Replaced that, refilled the cooling system and started the car up this evening. I let it warm up for a bit on idle and then raised the revs to 2,500 for about 25secs, when I looked in the engine bay after this I found all the coolant leaking out from under the thermostat housing at high speed. The radiator and all the hoses are completely cold, even the engine itself wasn't up to normal running temperature.

Am I right in thinking this sounds like water pump failure, or is it more likely something else? The water pump was refurbished by the last owner barely 5,000 miles ago, but it may have been done incorrectly...

[Toledo Man]

Check the bypass tube before condemning the water pump. They're prone to leaking. It is possible that your non-opening thermostat has caused the O rings to fail. It might be worth trying new O rings but replacing them necessitates removing the inlet manifold to get to the bypass tube. Did your replacement thermostat have the jiggle pin?

[sprint95m]

Am I right in thinking this sounds like water pump failure, or is it more likely something else? The water pump was refurbished by the last owner barely 5,000 miles ago, but it may have been done incorrectly...

Sorry to learn of your problem.

You need to do a few checks to give answers to some questions....start with a compression test. What are the readings.
Is the coolant escaping from the water pump bypass tube or is it actually leaking from the slot in the engine block below the water pump cover?
Had the coolant level dropped when it overheated?



Please let us know what you find.



Ian.

[captain_70s]

Did a compression test with the car cold, don't really want to get it hot as cooling it is impossible!

Results:
1 - 145psi
2 - 150psi
3 - 150psi
4 - 155psi

The water is coming from the round slot shown here:



Apologies for the poor picture hard to focus with grubby hands and a touchscreen phone!

I'm not sure if the coolant level in the expansion tank is dropping, it's hard to see, but even with the car running all the hoses were cold and soft, didn't feel like they had anything in them...

[Toledo Man]

Your compression readings are within 10% of each other so your head gasket is fine.

Yeah, that's where the bypass tube is. I reckon that because the old thermostat wasn't opening, the pressure in the bypass tube built up and the O rings have let go hence the leak. They're cheap and easy enough to replace but as I said earlier, the inlet manifold has to come off.

[Edin Dundee]

Get yourself a new tube and O-rings.
It is sometimes possible to remove the tube by taking the thermostat out and using long-nosed pliers with out-turned jaws, pushing them past the tube, opening them and pulling the tube up, but I've only managed to to do this on new tubes.

If you have to take the inlet manifold off, get some decent gaskets (Fitchett supplied my last ones or maybe try Robsport, the Rimmer ones were so thin you could spit peas through them) and an O-ring.

A thin coating of vaseline on the gaskets and O-ring, re-fit the manifold, and then pop the tube with vaseline-lubricated o-rings through the hole in the bottom of the thermostat housing.
Be prepared to encounter stripped threads on the head where previous fittings have been over-enthusiastic!

If your feet get wet when re-filling the cooling system, remember to fit the bypass tube.

[sprint95m]

Further to the above,
I suggest you go a stage further, since you will have to remove the inlet manifold anyway and
investigate the water pump itself.
Please remember to remove the battery and drain the entire cooling system first (there is a plug (3/4"AF) in the engine block
visible behing the starter motor).

Before fitting the inlet manifold gaskets, please offer them up to the cylinder head to confirm their alignment is correct.
Some trimming may be necessary.




Ian.

[Jon Tilson]

Yep...bypass tube.

Manifold off.

I would recommend doing the water pump seal as well but its a moot point. You are half way there with the manifold off.

Wiki guide if you need it here...

https://www.dollywiki.co.uk/wiki/Water_Pump_Overhaul

Jonners

[Toledo Man]

Ian, Fitchett's inlet manifold gasket set was fine when I had to do an inlet manifold swap so that's the one to get.