Automobile heater motors/wiper motors on boat

[Gary MullensParticipant @garymullens12074]

Hello, I am searching for pics or information on tugs with automobile fan heater blower motors/wiper motors. I am researching this information because I am in the process of building a river push boat. Length will be 60" and the width is 24". It will have two motors and I am thinking of a mixer with this set up.





Anyone here on the forum please respond with pics and information. Also, feel free to suggest other motor setups for this type of boat hull. Components, links would be appreciated.





Than

[Gary MullensParticipant @garymullens12074]

[ashley needhamParticipant @ashleyneedham69188]

Gary. Hello and welcome to the forum.

​Car wiper motors were a great source of motive power in their day, and likely because they were cheap and available, run on 12 or 6V besides having a good torque to drive heavy bread and butter or solid carved wooden hulls.

Today the situation is much better. Car wiper motors are likely now to be much more expensive and likely only to be controlled via a computer on the car (I made that bit up) BUT model boat motors are now relatively cheap, of good quality and readily available.

​No one will agree on what motors would be best for your boat, as there are loads of options to do the job and no doubt several people will offer alternative choices and you really have to make your own mind up. There are no right or wrong answers.

​The size of prop really determines the choice. Do you know what size you will be fitting??

Ashley

[Malcolm FraryParticipant @malcolmfrary95515]

Automobile electric motors are usually high quality builds, but information regarding their power is sparse. The only clue is usually the fuse rating in their native environment. Rather than using specific parameters, most people using these motors use the "TLAR" method.

Don't forget window motors and radiator fan motors. Lots of torque wanted rather than screaming revs. Older car peripheral motors were field wound, stick to modern stuff. Permanent magnets and compatible with any brushed controller that can handle the current.

TLAR = That Looks About Right

[Dave MilbournParticipant @davemilbourn48782]

I seem to remember that Vauxhall Astra blower motors are/were very highly thought of in this application. You might look at The Other Forum as it has a very full section on model tugs. **LINK**

Dave M

[Gary MullensParticipant @garymullens12074]

Posted by ashley needham on 02/10/2017 09:49:09:

Gary. Hello and welcome to the forum.

​Car wiper motors were a great source of motive power in their day, and likely because they were cheap and available, run on 12 or 6V besides having a good torque to drive heavy bread and butter or solid carved wooden hulls.

Today the situation is much better. Car wiper motors are likely now to be much more expensive and likely only to be controlled via a computer on the car (I made that bit up) BUT model boat motors are now relatively cheap, of good quality and readily available.

​No one will agree on what motors would be best for your boat, as there are loads of options to do the job and no doubt several people will offer alternative choices and you really have to make your own mind up. There are no right or wrong answers.

​The size of prop really determines the choice. Do you know what size you will be fitting??

Ashley

The boat I scaled is a twin screw boat and it use a 2" prop on either side. So my guess would be a 4 " prop on each side. Does this sound accurate?

[Gary MullensParticipant @garymullens12074]

Posted by Dave Milbourn on 02/10/2017 11:54:17:

I seem to remember that Vauxhall Astra blower motors are/were very highly thought of in this application. You might look at The Other Forum as it has a very full section on model tugs. **LINK**

Dave M

I'll check and do additional research. Thanks for the feedback.

[Trevor Drabble 1Participant @trevordrabble1]

Gary , I have at least 2 car heater motors available for sale cheaply which I have never used . If you are potentially interested I could try and do some tests on them for you . I did also have some manufacturers ( Smiths ) information somewhere . Will a!so have a look for that too if it would help .

Trevor .

[Gary MullensParticipant @garymullens12074]

Trevor, Sure. Let me know what you find out and the testing.

Thank you,

Gary

[ashley needhamParticipant @ashleyneedham69188]

Gary, is it that you really want to use car wiper motors or are you just asking for options?? A pukka brand new known quantity purpose made motor will deliver much better results than a wiper motor is likely to do, in addition couplings and so on are readily available.

​No idea if a 4 ish prop sounds like the right size without looking at the drawings. Tugs and so on do have much larger props than normal for the pushing/pulling power. This is a seriously large model prop and a specialist motor, or a geared unit is likely to be needed. The only way you will find out if the wiper motor cuts the mustard would be to make a test rig and run the thing with a wattmeter on the battery and see if the motor is performing satisfactorily.

​Ashley

[Gary MullensParticipant @garymullens12074]

Hi Ashley,

I would like to use a car heater blower motor. From what I hear and read hear and there, they are supposed to be good. Your thoughts? The plans before scaling, the vessel requires a 2" prop. Duel motors.

[ashley needhamParticipant @ashleyneedham69188]

Gary. No experience of wiper motors so unable to comment I am afraid. Modern motors should be quality items and I have nothing against using them, and on paper they should fit the bill, having been (presumably) designed for torque rather than speed and have a long life.

​If it scales to a 4 inch prop than that's what you will have to fit! I would certainly try the wiper motor on test with an ammeter or wattmeter though before fitting to the boat in case the load is just too much.

Ashley

[Gary MullensParticipant @garymullens12074]

Thanks, But I will be using a HEATER blower motor. Any issue with using the heater motors in reverse if needed?

[Gary MullensParticipant @garymullens12074]

Been looking at the heater motors and do I need to look at a 2 or 3 wire, one speed or two speed? Any other information I need before I buy? I see a lot of the motors have a shaft on both sides. Do you cut one of the shafts off?

[Dave MilbournParticipant @davemilbourn48782]

I would suggest 2-wire single speed for use with an ordinary PWM speed controller. Why cut one end off? It's not doing any harm; that's stuff is a swine to cut and you run the risk of getting swarf/filings inside the motor. Leave it on.

DM

[sammykParticipant @sammyk]

Hi Gary ,my tug boat has a car heater motor fitted.it turns a 75mm 4 blade prop and draws about 6amps at full throttle when tied up to the dock. the heater motors tend to run better in one direction, some have an arrow or a red dot, if unsure use an amp meter .it will draw less amps when its happy .buy the prop to use this rotation.

[Gary MullensParticipant @garymullens12074]

Posted by sammyk on 05/10/2017 19:20:32:

Hi Gary ,my tug boat has a car heater motor fitted.it turns a 75mm 4 blade prop and draws about 6amps at full throttle when tied up to the dock. the heater motors tend to run better in one direction, some have an arrow or a red dot, if unsure use an amp meter .it will draw less amps when its happy .buy the prop to use this rotation.

Could you post photos of your boat and how the motor is setup and components?

You can email as well

Edited By Gary Mullens on 05/10/2017 23:51:39

[Gary MullensParticipant @garymullens12074]

Are their any build threads with car heater motors? I have been reading articles on action electronics trying to educate myself on the setup. Now, I understand a single speed 2 wire motor will do but what about the 2 speed motor setup? Anyone care to share how the setup will work? The components etc? There has to be more info or threads on this. Right?

Now for my next question. What source is their for the 4 and 5 inch propellers?

[Gary MullensParticipant @garymullens12074]

Are their any build threads with car heater motors? I have been reading articles on action electronics trying to educate myself on the setup. Now, I understand a single speed 2 wire motor will do but what about the 2 speed motor setup? Anyone care to share how the setup will work? The components etc? There has to be more info or threads on this. Right?

Now for my next question. What source is their for the 4 and 5 inch propellers?

[Dodgy Geezer 1Participant @dodgygeezer1]

Posted by Gary Mullens on 07/10/2017 01:39:19:

Are their any build threads with car heater motors? I have been reading articles on action electronics trying to educate myself on the setup. Now, I understand a single speed 2 wire motor will do but what about the 2 speed motor setup? Anyone care to share how the setup will work? The components etc? There has to be more info or threads on this. Right?

…….

Your question seems to me to suggest that you think there is just one kind of 'car heater motor'. This is not the case. Manufacturers may use a variety of motor types – for all I know some may be using brushless motors. Unless you specify a particular motor we can only talk about generalities.

In general, car heater motors use a resistor pack to provide speed variation. This is quite inefficient, and means dumping heat somewhere – usually this is done by mounting the resistor pack with fins inside the car ventilation system. So, to use this technique (if you want to) you would need to obtain the resistor pack as well as the motor, and add a cooling fan. Resistor pack failure is a common problem with these motors.

Car wiper motors frequently use a different speed control technique which you may also meet on heater motors – they have a third brush unit set at 120 deg rather than the 180 deg separation between the two normal running brushes. Because the 120 deg brush sees less back EMF it carries more current, and the motor runs faster.

No doubt there are other more obscure speed control techniques you may meet on some motors. If you want to educate yourself about small electric motor design I can recommend this book by Jim Cox in the Workshop Practice series: **LINK**

[ashley needhamParticipant @ashleyneedham69188]

I do have one question…how much you would pay nowadays for a heater motor, spec probably unknown, compared to a commercial geared unit from any number of sellers (RS components have about 300 in their list), the spec of which you would know exactly.

​Ashley

[Malcolm FraryParticipant @malcolmfrary95515]

Posted by Gary Mullens on 07/10/2017 01:39:19:

Are their any build threads with car heater motors? I have been reading articles on action electronics trying to educate myself on the setup. Now, I understand a single speed 2 wire motor will do but what about the 2 speed motor setup? Anyone care to share how the setup will work? The components etc? There has to be more info or threads on this. Right?

Now for my next question. What source is their for the 4 and 5 inch propellers?

To control your motor, you will probably want to use easily available parts to go between radio and motor. Effectively, this means an ESC intended for model use, which is expecting a 2 wire motor. If the motor is a straight DC type, but with the odd extra wire for cheap speed control, it would be best to ignore the "extra" wire and just use the two that give "normal" performance, allowing the ESC to do its job.

At one time, it was possible to browse a scrapyard and select the goodies you wanted – nowadays, you need to know the make and model and year, if not the actual registration of the car you intend it for. Using a motor for any other purpose is a foreign concept, for the sellers, things like "technical specifications" are equally foreign. The only common point is that they are designed to work on a nominal 12 volt system. Unless it fell off a truck. Quite often a nice new "proper" model motor is a lower cost option with a high probability of getting a setup that works.

Raboesch list props up to 130mm, spotted on http://www.cornwallmodelboats.co.uk/acatalog/R147-M5.html Those are BIG props, and will need a big diameter motor (rule of thumb, motor diameter will be greater than prop diameter) or gearing. a toothed belt and pulley system would probably be the best option.

[sammykParticipant @sammyk]

Hi Garry i have posted some pics in my photo album ,they are of two models one called myia and one called shannon. .they both use car heater motors with m5 prop shafts with prop shop propellers. as Malcom says do not go to big on the props you will just get low running time.regards sammyk

[sammykParticipant @sammyk]

Hi any more questions just ask

Edited By sammyk on 07/10/2017 11:51:59

[Dave MilbournParticipant @davemilbourn48782]

These will do the job. Reliable, familiar, designed for the task. **LINK**

DM

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