Hi Torque starter motors

[154WHU]

Hi
I am sure this subject has been aired before,
What is the best Hi Torque starter motor ?
I am thinking of fitting one ,but cant make my mind up ,which is most suitable.

[flatfloor 3.8]

Mine is an EDGE available from Cambridge motorsport and is very good, quality is superb.

[JEP41]

Hi,

I have three Jaguars all with Cambridge Motorsport hi torque starters and they are excellent. Plus Cambridge Motorsport give excellent feedback to any technical questions. :D

[44DHR]

Mine is from Fosseway.

Again great quality and information provided. The hardest part was removing and manhandling the the old very heavy stock unit out through the frames. The lightweight Fosseway unit has studs fitted for ease of fitment and with the lower mounting accessible from the hatch opening inside the car footwell the fitting was a doddle. I made up an new extended lead from the battery as the new unit was obviously shorter than the old stock unit.

regards,

Dave

[MarekH]

Looking at this backwards, the high torque starter motor does nothing for you, one way or another, other than save your battery.

With an identical but fuel injected engine, you can datalog the parameters and startup quite readily and what becomes apparent is that the engine fires up when it has the correct air/fuel ratio for the ambient temperature, sparked anywhere over a wide band based around 5' btdc. The fuel injected engine achieves this by adding a priming pulse and then injecting fuel based upon temperature. My 13:1 v12 - a far more difficult load than a standard 6 - turns over at 120rpm on a standard Lucas starter and consistemntly fires up by the third cylinder to be be sparked after fuelling is commenced. (The other feature is that they use an idle valve which is typically more open during cranking than during normal running. To mimic that, you'd have to put your foot on the gas a bit. Having the engine less throttled at start should present an easier load to the starter.)

By contrast, a carburettored engine has a problem building up the flow of enough atomised fuel as it gets this by passing air over the jet. What then happens is that a proportion of this will probably condense on the inlet runners and it is harder to get enough atomised petrol into the cylinders. During this time, the starter is labouring away unproductively depleting your battery. Once the engine fires, the battery is recharged. I'd judge that the condition of the battery will be far more important than the starter to achievingf a successful result. What the geared starter motor does for you, if anything, is buy a bit more headroom for allowing you to have a poorly tuned choke before it becomes an issue to start the car.

I'm not against geared starters, but this is all that they bring to the table, no more, no less. Essentially what needs to be addressed is a fueling problem at startup, not an electrical load problem.

kind regards
Marek

[Mark Gordon]

I agree with Marek. With well-tuned carbs, 123 ignition and original Lucas starter, my car starts, summer or winter, even after sitting for two weeks within two seconds or less of turning. Gearbox in neutral, foot off of the clutch, choke on, ignition on, allow fuel pump to charge the float chambers (i.e. stop ticking), hit the starter button and bingo! I really don't believe that hard starting problems have anything to do with the starter unless the starter is worn out. A properly sorted fuel and ignition system is the key.

[44DHR]

The high torque starter is considerably lighter and smaller than the stock unit - weight saving. Try holding up the stock motor with one hand !!

The high torque starter spins the engine at higher rpm than the stock unit.

The high torque starter takes less load from the battery.

The high torque starter uses modern technology and components which could - repeat could - be more reliable. Most are Japanese - shock horror !! - Denso units.

The high torque motor with studs fitted is considerably easier to fit than using the stock motor method of bolts.

The high torque starter motor can easily be removed and the old stock unit refitted when required.

The only downside is the higher pitched cranking noise - most un-Jag like.

The 6 cylinder Jaguar engine is a big old beast to get cranked over. I certainly did not have any problems in starting before fitting the high torque motor, but it cranked over slower whilst taking drain from the battery and took more time to fire from dead cold start. With the high torque motor it fires much quicker from cold start.

regards,

Dave

[Heuer]

I found in high ambient temperatures and after a spirited run the Lucas starter would sometimes stick and be reluctant to turn over which is always a heart stopping moment! Originals work but for the cost involved the high torque versions remove another point of failure. Ditto the Nippondenso alternators.

[malcolm]

If you have a ramp, is it easier to get old out and new in from under the car?

[osgii]

No because you must remove the starter from where the vacuum tank is. So no need to do this from underneath the car. I did it alone, but it's easier and safer to and 4 hands to do the job: one is unscrewing the bolts from inside the car from the right side, and the other is handling the big thing and waiting for its release.

[malcolm]

I found in high ambient temperatures and after a spirited run the Lucas starter would sometimes stick and be reluctant to turn over which is always a heart stopping moment! Originals work but for the cost involved the high torque versions remove another point of failure. Ditto the Nippondenso alternators.

Hi, I looked for nippondenso alternators on line, and the only site selling them said "not available" for the XKE engine

Where did you source yours from? Any link?

[Heuer]

viewtopic.php?t=6668

The Nippondenso part number is in the thread and they come up on eBay unless Angus has hovered them all up by now! They used to be about ?25 new but an inexplicable sudden rise in demand means they are now somewhat more expensive.

Here is one at the moment: http://tinyurl.com/o77d7me

[malcolm]

Thanks for that - would it fit straight on to a series 2 4.2L engine, or would I have to change plates/brackets etc?

[Malk]

Anyone fitted the Fosseway alternator too? plumped for that and a hi-torque starter motor, only thing left is radiator and cooling which will do once bonnet gets painted in the winter if anyone has recommendation for V12 rad and fans be good to know please.....

[Heuer]

Thanks for that - would it fit straight on to a series 2 4.2L engine, or would I have to change plates/brackets etc?

A straight swap although you will need to make up a small sleeve and spacer as described in the Upgrades Forum. Not bad for ?35 compared to the ?175 charged elsewhere for the same thing! You will also need a Denso plug which costs about ?8. Looks like that one has gone and the only other listings are at ?110.

[malcolm]

Thanks David, At least I know what to look for now.

[Alty Ian]

Just fitting a high torque starter,....

Do I keep the original starter spacer ring or remove it?

[vee12eman]

Anyone fitted the Fosseway alternator too? plumped for that and a hi-torque starter motor, only thing left is radiator and cooling which will do once bonnet gets painted in the winter if anyone has recommendation for V12 rad and fans be good to know please.....

Hi Malcolm,

First thing to do about the cooling system on a V12 is to make sure it is well flushed, as clean as possible and fill it with a good quality anti-freeze/coolant designed for alloy block and heads. Header tanks can be a problem - they rust out and it seems to be harder to get a decent alloy tank than for the six cyl cars.

The Otter switch is as notorious in V12s as in sixes, so probably best replaced with a modern unit - speak to Mike Eck at Coolcat who will supply the new switch and of course the "T" piece adapter to fit it. This gives the advantage of several temperature ranges for the switch, as the new unit is a common fit available in a great range - Mike will advise you. He also sells an alloy rad at a good price and has a great reputation, but beware import duty to UK on items like this. I say this because the cooling fans I bought from America, from the excellent V12S site, arrived at a low cost in the UK landed, but then were loaded over 33% in import tax by my friendly local Post office depot - how that equated to the 17.5% VAT at the time I never found out.

If you go for a set of new fans, it's actually quite easy to buy some modern low profile fans and a simple cowl can be folded up from Aluminium sheet to house them, much cheaper. There is also a mod using VW Golf (I believe) fans and motors which fit straight into the original fan motor brackets. Look on Jag Lovers for this mod.

Lucas style relays are now getting old and the replica version I bought from a reputable dealer fused shut on first use. This may well have been because the new fans have greater current draw, but anyway, I replaced the single Lucas style relay with two Hella/Bosch style units, one for each fan. Now if one of the relays fails, the other should still operate to give some redundancy. My wiring diagram for this can be found here:

http://dl.dropbox.com/u/8496016/S3%20Fan_Relays.pps

Please note this wiring diagram is a modified version for two relays, not the original. It is clickable and you can see how the system works. The new loom fits straight onto the original wiring connectors in place of the original, but I used new cables and also fitted a modern inline fuse to protect my wiring.

An alternative for the radiator is to get yours flushed and tested, replace with a new copper unit or, as I dd, buy an Aluminium unit locally, in my case from Northampton Auto Rads (NAR). I got mine as a slight second at a Stoneleigh Jaguar spares day. Incidentally, the aftermarket alloy rad cowl from V12S fitted the aftermarket Alloy rad from NAR almost perfectly - I had to open one hole about a mm, a good example of quality aftermarket products.

I upgraded knowing I was planning to move, and the system has performed really well, even in 40 degree Centigrade and above temperatures. I also replaced my originally purchased, but pathetic Kevlar "Reinforced" hoses with regular cotton braided units and after a week or two of chasing weeps from new hoses as they bedded in and I had to tighten the clamps, the system is performing well.

Generally the V12 cooling system is great when in good condition, more problems occur because of poor maintenance. My engine was badly corroded and silted up, so much so that I had to replace the block and heads (although keeping the original internal moving parts). This would have been caused by inadequate coolant. The aforementioned flush may help this, but if you use a pre-flush, then make sure you both back and normal (relative to flow) flush the engine and radiator (preferably separately) with a garden hose, running against the normal flow direction, until the water runs clear. This is designed to flush particles back out the way they came in and will need a LOT of water, especially if it wasn't maintained properly before. (You need around 27 litres just to fill the system)This, and probably the switch change, is probably fine for UK cars.

All traders mentioned gave me great service and can be found on the internet. Good luck and successful cooling!

Regards,

Simon

[PeterCrespin]

The high torque motor with studs fitted is considerably easier to fit than using the stock motor method of bolts.

The high torque starter motor can easily be removed and the old stock unit refitted when required.

Au contraire, assuming the studs are fitted to the motor flange? I have never removed/replaced a starter requiring access to the bell housing side of the fasteners and on a car without an access hatch in the tunnel I wouldn't fancy trying.

I've always used bolts fed from the back forwards so that you do all R&R work from the front of the engine, using stacked 3/8 socket extensions to remove the nuts, leaving the bolts in situ, welded together by a hoop of round bar a la Mk2.

Pete

[abowie]

Looking at this backwards, the high torque starter motor does nothing for you, one way or another, other than save your battery.

Mine saved my life. Well maybe a slight exaggeration.

My car stopped dead in a 100km/hr zone on the freeway last month. There were huge trucks going past my driver's door less than a foot away. I could not safely get out of the car nor push it. I was able to use the starter to drive the car over 100m in first gear and this got me out of the lane and over onto the hard shoulder. The stock unit would not have done this.