Pre-heater

[WokingWedger]

The reason to consider this is for mechanical sympathy for the car(not me worried about being cold in the winter mornings.

When possible during the winter my car will be take for short runs and when not possible will just be started to circulate the oil, but I am worried I may being doing more damage than just leaving it alone.

Apparently most engine wear happens during the fist few minutes of starting, but how much of this is due to components not being up to optimum temperature (limits and fits etc)and how much of it is due to oil not having circulated around the engine fully ?

Has anyone any experience of such 'pre-heater' things.

Options vary from simple 'under sump, heaters (not connected to the car in anyway, to electric heaters and pumps in the coolant cicuit.

I guess the old under sump jobbies were used before oil technology rose to the challange of thin oil at low temperatures.

Can you buy electric oil pumps to 'prime' the top end before starting ?

Any thoughts from anyone ?

[morebeanz]

There were some posts on this a month or so ago, I think. It seems like a good idea, but given the varied circumstances of peoples storage and driving needs, I'm not sure it's become particularly popular. It doesn't help that many of us have a "keep it light" view on the car (even if eating too many pies ourselves! )

I know that the Cerb oil often doesn't come up to operating temperature at all if it's very cold.

Most of the pre-heaters seem to pre-heat the engine through circulating warmed water through the cooling system. This would help with normalising the metalwork a little (expansion, etc), and I guess the oil would warm very quickly after that.

[Zumbruk]

I fitted a Kenlowe pre-heater to my Range Rover a few years ago in order to make it more comfy on winter mornings, reduce engine wear and fuel consumption and partly to "fix" a cold running problem that no-one could fix...

They work by using a small pump to pump water over a 3kW heating element. You install them in a radiator hose. I used a timer to switch it on half-an-hour before my usual leaving time. While it it worked, I was very happy. The car was toasty from startup and seemed to run much better.

But ... one morning, the alarm clock failed to go off. The house mains was out, and after some investigation, it appeared the house RCD had tripped. OK, no problem, I reset it, got dressed in a hurry and out to the car. There's some coolant on the drive, but I don't have time to investigate, so unplug the heater and drive away. After half a mile, the car stalls and won't restart. More investigation shows that there is no coolant and it has massively overheated. I wait for it to cool down, drive home, get out of the suit, call the office to tell them I am going to be late and have a good rummage under the bonnet. What has happened is that the thermostat on the heater has failed short-circuit and it has boiled the coolant away. Then the pump seals failed and the remaining coolant squirted out, then the wiring insulation failed and short-circuited the mains, tripping the RCD. I remove the damn thing, refill with coolant and fortunately there doesn't seem to be any harm done.

I find the receipt and the heater is still under Kenlowe's two-year warranty (just), so I call them to claim and they deny I ever bought it. I fax them the receipt (I bought it directly from them on the web) and they (reluctantly) send me a new one to the wrong address. When I finally get it, I sell it on eBay and report them to the VAT man for failing to keep proper business records. Their attitude means that I will never buy another Kenlowe product ever again. If I were to fit another heater, I would also fit a thermal fuse to prevent a re-occurence of this incident.

[WokingWedger]

That rules out the Kenlow option then

[That Daddy]

If your not going to drive it, leave running engine for short periods alone(your just putting condensation into your crankcase),if left for extended periods then just rotate the engine by hand to undo loading on the same valve spring/s(parking the cam in another position)i have always done this with all my motors when left standing,including highly tuned power units,just remember when you do start after long lay/up run straight onto fast idle 2k approx to take the loadings off the camlobesdont just start and let it idle,the standard fast idle on this motor is to low,all IMHO of course

Edited by That Daddy on Monday 10th December 09:55

[Number 7]

I ran a Kenlowe unit in my 350i for a few years when it was our only car. It worked pretty well, but siting them can be difficult, as ideally they need to be lower than the highest point in the system (to avoid airlocks). If I needed to use a TVR all year round, I'd fit another.

7.