Over heating P2

[luli]

The Rover P2 owners handbook recommends to fill the radiator with clean spring water, and probably that what had been done for many years. Such water leave limestone deposits that over the years reduce the heat conduction from the cylinders to the cooling water. Vinegar is effective in disolving limestone and rust. You can see here how I had cleaned an engine block before overhauling it: http://wp.me/pXLKy-21U

[Klaus]

Luli, very interesting technique, to dissolve limestone with vinegar in the engine block's water jacket. Works with steam smoothing irons or water boilers, too

The theory behind it is to convert CaCO3 (chalk/limestone) into water-soluble calcium and carbon dioxide (CO2) using some kind of acid. Hypothetically, one could also use an even stronger acid than vinegar, e.g. hydrochloric acid (HCl) or sulfuric acid (H2SO4) in higher concentrations to dissolve the limestone deposits in the block more thoroughly. This would possibly make removing the residues much easier. Question is, how low a pH will the block's metal or the water seals and gaskets (if still in place) tolerate before being attacked by the acid?

[wooster]

I decided not to use an acid as I have not completely stripped the engine (I have just removed the head) and I was worried about what damage acid might do to seals and gaskets etc.

[luli]

There are no seals, gaskets etc in the block water ways. They are all in the head. There is only one drain valve and several Welch plugs. If you use diluted vinegar and let it sit there for several days - it will do the job. I agree with you that "real" acid may be harmful.

[wooster]

I intend to ask my engineer to open up some of the waterways towards the rear of the head of my 14 to improve coolant flow around the rear two cylinders . Does anyone know if I should request a specific amount by which the holes should be bored out? Is it worth narrowing a few at the front to alter the flow of coolant? Thanks.

[lakesrally]

There was an article published in Freewheel years ago with the details but I've not got the info here at work. Contact Anne-Marie Rowland, she should be able to supply a copy of the article, contact details in Freewheel.

[jefflee]

Hi Wooster.
If your engine is 1577cc the engine has a water feed to the back of the block and should only need a good clean to the waterways.
The work done on opening up rear waterways was on later 6 cylinder engines where water was fed back only to the 4th cylinder
and 5 & 6 was a little short circuited .
Also my 1936 14 will overheat when pressed hard on a hot day with only one fan blade but is fine with two X blades.
cheers Jeff. Lee.

[lakesrally]

Thanks for putting me right Jeff, I thought it was all the 6 cylinder cars.

[wooster]

It was Mike at Meteor Spares who suggested I get it done.

[jefflee]

Hi Rich.
Your engine is the later 14hp. 1900cc and would be improved by the modifications.
Harry Johnson & Peter Humpherson in York did extensive tests on this type of engines
water flow and as Stewart says the details were put in the Freewheel at that time.
cheers Jeff.