STARTER MOTOR - HIGH TORQUE TYPE

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Green912
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STARTER MOTOR - HIGH TORQUE TYPE

Post by Green912 »

Hi Everyone

I am having problems with my existing starter motor. I guess it's one of the original and tired and struggles to turn over the motor at a reasonable speed to draw fuel (original refurbished fuel pump) to start the car. Engine 912 - 1720cc.

I have checked all the usual problems, earth straps - front and rear, (even fitted new ones). I have cleaned the earthing points etc. but the starter motor still appears to struggle. Battery is good.

Has anyone upgraded to a better starter, if so, which and what have been the results?

Looking forward to hearing from you!

Many thanks.

Adrian (Green 912)
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by neilbardsley »

I found in my 12v cars the normal starter is good enough. However, I did have a relay fitted to mine which bypassed the ignition switch but I'm not sure that is your issue because once the solenoid engages the starter should be drawing current directly from the battery.

I would be tempted to check the grease on the bell housing. This was an issue with my 6v starting. You don't mention how old the starter is? Maybe it's needs replacing or you can open and clean. However, a professional service if a starter will probably cost more than a new one

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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Timo »

The starter motor on my car used to be really sluggish when I first bought it, and only turned the engine about 50% of the time, the rest of the time it would just spin without throwing the dog into the flywheel. The starter in question was a reconditioned stock Bosch unit.

I swapped it out for a high torque one about 14 years ago and have never looked back, the high torque unit spins the flywheel about twice the speed of the old one and consequently the car starts far easier.

If you are having issues with a tired standard starter I would definitely recommend upgrading to a high torque one.
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Ashley James »

I’ve got a 6 volt high torque starter on my 356 and the standard Bosch on my spare engine. There’s not much difference except that the high torque one doesn’t need the bush in the bell housing and is much smaller and very easy to remove and replace.
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Ollie »

I've got a Power Lite starter which performs superbly. It replaced a tired VW starter that was struggling to turn the engine over.

https://www.powerlite-units.com/starters/rac508.html

Having just seen the price again I must have been feeling flush that month :lol:
Green912
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Green912 »

Hi Ollie

Looks like a great starter motor, quite pricey, but expect it will do the job. I will investigate further.

Many thanks
Adrian
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Green912 »

Hi

Have purchased the Powerlite starter motor and fitted it, yes it was pricey, but it has made a massive improvement to starting the car.

Many thanks Ollie for the suggestion.

Next job, replace the rusty and leaking fuel tank!

Adrian
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Knoxy »

Hi Adrian

Good choice, a higher torque starter has been on my radar for a while.

You mentioned the original starter was struggling to turn the motor over to draw the fuel. My car had the same issue if it was not started every week or two. The starter needed to turn an unhealthy amount of time trying to get the fuel up to pressure. I generally had to remove the air cleaners and squirt some fuel down the carb venturis with a syringe to get the motor to fire with enough momentum to get the fuel pump running at speed. I read on one of the 356 forums in the US that this was not that unusual as after a decent run the fuel in the float chamber can evaporate due to the heat conducted through the manifolds (my car is running Webers which don't have the Phenolic Blocks on the manifold) additionaly the fuel can "percolate" back down the fuel lines if not used. The little mechanical pump then struggles to re-prime the system. The suggestion was to fit a fuel primer bulb, as used on outboard motors etc. This seemed really Heath Robinson but it was a cheap easily reversable fix, so I thought I'd try one. This completely solved my starting issues.

If the car has been sitting for some time without running, I now turn the car over a couple of times to get the oil flowing, then squeeze the primer bulb a few times until I can feel resistance, then a few pumps on the throttle pedal and the car fires straight away.

Thought this might be useful for anyone experiencing similar issues.
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Knoxy »

Image
“Change is easy. Improvement is far more difficult”. - Ferdinand Porsche.

Helga the 912 Light Ivory 1967 (same age as the missus but in considerably better nick)
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Knoxy
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Knoxy »

Image
“Change is easy. Improvement is far more difficult”. - Ferdinand Porsche.

Helga the 912 Light Ivory 1967 (same age as the missus but in considerably better nick)
Ruby the Merc - Mercedes Benz S123 200T Estate
981 Cayman (Sold)
Cayenne - (Sold)
Green912
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Green912 »

Hi Knoxy

The primer bulb looks like a worthwhile addition, especially if the car has been standing for a while. Thanks for the posted photos. (Your car engine bay looks great!).

Adrian
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Timo »

Hi Knoxy, my car has always suffered with the same percolation issue you mention.

I'm thinking of investing in one of those primer pumps, I like the look of the one you have used as its quite small compared to some I've seen. Can I ask where you purchased yours from?

Also Love the metal fuel filter, where did you get that?

Cheers

Tim
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Knoxy »

Hi Tim

I really works a treat and is easily removable if you want to go back to stock. I was a bit concerned that it may have some impact on performance but I can confirm that if fitted in line before the pump, once the engine is running, it becomes flow through and has zero impact irrespective of how spirited you drive.

I just purchased mine on Amazon to try, I was a bit concerned because it was Chinese but it is decent quality, has aluminium fittings, its been fitted for a couple of years now, it is holding up fine and it is not affected by Ethanol.

Here is the link https://www.amazon.co.uk/ePathChina®-Pr ... p_d_rp_1_t

The fuel filter is from a modern car, I think it is actually for a Nissan. Unfortunately I don't know which model, it was purchased at an auto jumble as NOS for its size and appearance and was fitted to avoid the affects of Ethanol that you get with plastic filters. I fabricated a simple mounting bracket from Aluminium flat bar with some neoprene fitted to prevent metal to metal contact. It's not really period or OEM but given the historic Carburetor and Fueling issues my car had (see historic posts), it was more important to get something capable of dealing with modern fuel.

The combination of the Weber conversion, with the adapter plates I made so that I could fit the original Knecht Air Filters thus retaining the nice induction noise, a fuel pump rebuild, the fuel bulb for priming and running Shell V Power means the car starts and runs exceptionally well for the last couple of years and I have the confidence that I can get her started irrespective of how long she's been standing.

If you fit one, remember my tip to crank the car before priming the fuel line to get some oil around the engine, as in my experience, the car fires into life first crank after priming.

Hope this helps.
“Change is easy. Improvement is far more difficult”. - Ferdinand Porsche.

Helga the 912 Light Ivory 1967 (same age as the missus but in considerably better nick)
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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Knoxy »

BTW, the Bulb has an arrow denoting the direction of fuel flow so watch out for this.
“Change is easy. Improvement is far more difficult”. - Ferdinand Porsche.

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Re: STARTER MOTOR - HIGH TORQUE TYPE

Post by Mike Smith »

A Pleasure to see a Clean & Tidy Engine bay - also proper hose clips and not those bloody ugly Jubilee things
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