Hi-torque starter motors

On 2 cars with these, there is terrible noise, and a bit of hesitation or even temporary stop/pause in the turning action.
On a 420G it stopped working after 6-7 yrs. It proved to be really poor quality inside.
And on an XK 150 with R engine from an E-type, the starter is so weak that it will never start the engine.
I think an overhauled original starter is better, but there are very few shops these days that do it

You have really had bad luck and perhaps other problems you attribute to the starter motor.

I have installed hi torque staters in four old cars, including 2 xk6 engines, and have always been very happy with them.

Agreed: the one I put in the Rover made it eminently more usable, and provides much more reliable starts than the original Lucas. That’s not so much the fault of the Lucas starter, which is identical to the one in the E type, but because it’s used on a high compression four-cylinder.

I agree - a good quality hi-torque is a big improvement. My '68 Mustang and '68 Cooper S both have them, and I have one in the box ready for my XK140, when I get the engine built. The Mustang’s has been on for 18yrs and 45,000, the Mini’s for 9 years and 15,000, neither have missed a beat.
You might want to check installation - correct number of teeth, degree of mesh etc. Sometimes spacer shims are needed to adjust this.

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My Healy 3000 has had one now for five years, no problems. MK2 just fitted one six months ago, seems fine. I think you’ve been unlucky.

Ian

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Peder

It might just be you’ve just had cheap knock off ‘high torque’ starters, which are definitely out there, some being just ‘rebuilt’ used units. I’ve had a half dozen or so of the higher quality gear reduction starters in various cars (I replace the original English units as a matter of course). Still have two in my current cars, the oldest one going on 29 years (it’s a Tilton brand). Don’t recall the brand in the E-type, but was purchased from Classic Jaguar 18 years/20k miles ago.

One does have to verify proper engagement and operation when doing the initial install on these things; not because there is any issue with the starter but because over the decades less than thoughtful ‘mechanics’ change ring gears, or leave out motor plates and/or starter spacers, or swap in mismatched parts when ‘repairing’ their prized machines.

When I installed the Gustafson starter, originally meant for my E type, on my Rover (they both use the exact same starter and Pinion), I had the crank and flywheel mounted in the block, and the adapter plate between the transmission and the engine was where the starter mounted. I made very sure that engagement was positive and proper.

I’m glad I did. It has worked flawlessly now for about five years.

I had a hight torque starter on my compact 420 sedan. It worked fine. It won’t spin an engine fast enough with spark plugs removed to pre-oil, but with plugs in kicks it over no problem. My only thing I didn’t care for is it sounds like a Toyota cranking over.

That’s odd: I used the original, slower-cranking Lucas starters on quite a few hundred of those engines, and they brought up oil pressure just fine. The high torque should do it quicker.

Makes sense to me with the gearing, the small motor will have to turn way way faster whereas the big Lucas turns leisurely with all its torque and would turn much faster without load. I’m confident that the big starter has much more headroom with the bearings probably the limiting factor… say hypothetically both motors would run at a similar speed with little load. One has a gear reduction.

I think the gearing limits the unloaded cranking speed. With spark plugs installed It definitely cranks quicker or without hesitation…

In every instance I know of, the hi-torques spin the engine faster than the Lucas, under load, or not: faster spinning isn’t going to lead to slower rise in oil pressure.

A drill will spin faster in 2nd gear than in 1st.
Unless it’s loaded, then it spins faster in 1st.
The starter motors should be analogous to this.
Maybe there are different starters out there.
Faster spinning obviously leads to an earlier pressure reading.

David, I measured the unloaded rev rate of the two starters, when I put a hi-torque in my Rover (which used the exact same Lucas as the Jag): it spun faster.

Ditto the engine, when I measured the spin rate at the crank.

I still have no conception how the high torque starter could make it so that the oil pressure came up slower.

I’m with Paul on this - I’ve fitted a lot of high torques in Healeys, Minis, Triumphs, Mustangs etc. and all spin significantly faster with plugs out than the old original heavyweights. On all these cars I have never had a problem generating oil pressure on the gauge before first start-up, which I do routinely.

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I believe you, and am not trying to fabricate reasons to keep original starters (that are not useless old junk), I’m just trying to find an explanation for Tims experience. I believe him as well.

Reality aside a gr starter should turn slower with little load, but that depends a lot on the motors and their design, that’s clear.

Oil pressure has nothing to do with the starter model, and a lot with cranking speed - but that fact was never challenged?

I’ve installed exactly one, in my 4.2 FHC. When starting the car, it cranks the engine at a higher speedthan the original Lucas ever did. I assumed it is just a more efficient design.

Not all high torque starters are the same…depends on manufacturer and model. …some spin faster and some have more torque…most will sound faster…just look up the different manufacturers specs…the problem in spinning up to see oil pressure is that many owners dont leave the starter spinning for long enough to see the pressure register…it takes much longer than many think…Steve

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Quite right, it takes a while. A long while, if you forget the oil gallery transfer plug at the back of the inlet manifold base in a Ford 289 (ahem).

I usually pressurized the oil system with a pressure pot before I do the starter method.
I was not impressed with the slow speed it cranked unloaded. But it was a good starter in use. To each his own. Use what works for you. Both my cars will have refurbished Lucas starters until I have a reason the swap to a different starter.

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