Monday, January 1, 1990

Your site doesn't allow me to enter my complete shipping address. HELP!

The shopping cart and checkout functions on our web site are actually Paypal functions that we link to.  When paying with Paypal, be sure you have your correct address defined in your Paypal account BEFORE you place your order and "check out" on our site, as the zip code you enter while viewing your cart contents is just for a shipping estimate ONLY, as the system does NOT know who you are until AFTER you log into Paypal account further into the "check out" process.

So, the proper procedure to make sure we get your current shipping address would be as follows:

1) Log into your Paypal account
2) Click on "Profile"
3) Click on "Add or Edit Street Address" and update accordingly
4) Log off of Paypal
5) Go to
6) Place your items in the cart
7) Check out when you are done with your order - your "updated" address will be used.

I did not receive all of my order. What’s the deal?

If you ordered plans and parts, they are shipped on the same day, but in separate packages.  It is very common for them to get separated in the mail and arrive on different days.  On international orders, parts may take a few weeks LONGER because they must pass through Customs.


Can you answer technical questions on your plans?

I love to build things also, i.e. a house, outbuildings, a couple of boats, etc., but I am not a machinist.  I was a database programmer/analyst by trade.  Dad of course was the expert machinist, but he passed away in 2009  :(  I have a basic working knowledge of most of Dad’s projects, but I cannot answer real technical questions.

Fortunately, Dad's plans are very detailed and complete, and any experienced builder (and most novices) should have no trouble at all.  Occasionally a builder may have a question or may not completely understand something, and if I cannot answer your question, perhaps someone else can, as hundreds of these engines have been built - perhaps thousands (I see them running at the shows all the time).

Search our blog by engine name and I may be able to put you in contact with someone who has successfully built the engine you are working on.

Also, there are lots of users in the big forums ( and who have built a lot of Dads projects also who can assist with technical questions.  Also, check out youtube as many builders make and post videos of their running engines.  Most will be happy to answer any questions you may have.

What is the horsepower or torque rating for these engines?

Sorry - I just don’t know! 

Dad designed and built these primarily for recreational and educational (hobby) purposes - and not really for any real-world application (although some could be put to real work!)

I live outside the U.S.A. How much is shipping to my country?

Our web site,, can automatically compute shipping cost BEFORE you check out.  Cost is computed by the total order weight, and can vary from $8.55 to well over $20.  Just click on the Ship outside U.S. link when viewing your shopping cart.  Our web site also accepts Paypal and Credit Card payments.

I placed my order more than a week ago. Where is it?

All orders received by 10AM ET Mon-Fri are usually shipped out on the same day.  Orders received after 10AM will be shipped the next business day.

I always update the Paypal status as "Shipped" right after I print your shipping label, and you should receive an e-mail immediately after I update Paypal, so please check your e-mail program and look for the shipping status update and tracking# (if applicable) e-mail from Paypal.

Note that parts on overseas orders must pass through Customs - this can delay delivery for a week or two (or three!)  For more info, click the link below:

Do you offer discounts for schools? Do you accept Purchase Orders?

Ordinarily, a set of plans must be purchased for each engine built, but for schools using our plans for a class project, you need to purchase just one set of plans for each class, regardless of class size.  So if you have 1 class of 100 students, then you need purchase just one plan set.  If you have 5 classes of 4 students, you would need to purchase 5 plan sets.  Additionally, when the projects are complete, we request that you send us a class photo with all the engines and students in a photo.  We like to post these on our blog.

We do accept purchase orders, however, the first one must be for plans only. This is a small, part-time endeavor, and I do not have the resources to perform credit checks.  After I receive payment for the first PO, I will then accept PO's for hardware/parts.

I just placed an order. Why are shipping charges so high?

Shipping charges are reasonable, and is meant to cover my expenses, which includes envelopes, cartons, packing material, Paypal fees, postage, and insurance when value is $50+.  Shipping charges are based on order weight and can vary from $5.00 to well over $20.   If you purchase a lot of small parts (like magnets, Hall sensors, plug clips, etc), the Paypal shipping calculator will probably over-charge you.

I always try to be fair, and if you are overcharged by more than $2.00 or $3.00, I WILL SEND YOU A PARTIAL SHIPPING REFUND via Paypal upon YOUR receipt of the order.

Why don't you accept phone-in orders?

We wish we had enough orders to make this a full-time business, and we are very grateful for the orders we do receive, however:

1) We have jobs outside the home, and thus we are not here much during daytime hours.  In the evenings we really want to relax like everyone else.

2) We would have to enter your information (name, address, phone#, email, credit card, info, etc) on our web site the exact same way that you can do it yourself, so there's no advantage to having us do it for you.  We would just be a middle-man, and thus more potential for mistakes and typos.  For those worried about  "internet security", it wouldn't be any more secure if we do it - probably less!

We do accept mail-in orders with checks and cash.  See this link:

TIM6 Ignition Module Troubleshooting

The most common problem is an insufficient ground between the TIM6 board and the engine block head.  Note: this applies to 3 wire coils only!  Make sure this is a good tight connection.  Sometimes I recommend two ground wires from the board to two different places on the block to make sure.  If the board is not properly grounded, high voltage from the coil will back feed into the Hall sensor and will blow it out.  It could also blow out the transistors on the board.  Ultimately, there should be NO resistance from the spark plug threads on the head to the ground connection of the ignition module.

Another issue I have heard of is a spark jumping from the Hall sensor directly to the engine frame.  Make sure the Hall sensor is sufficiently separated from the engine frame (1/2"+) or well insulated from the engine frame.  This includes it's legs and wires running to the TIM6.

Problem: LED does not light.
Solution: The LED should light each time the magnet passes under the Hall sensor.  The Hall sensor should be no farther than 1/32" from the magnet when the magnet is directly under.  Also, the polarity of the magnet is critical.  The south pole of the magnet should be facing the Hall sensor.  If the distance and polarity is correct, you may need to replace the Hall sensor.  Temporarily bypass the Hall sensor by shorting pins 2 and 3 of the Hall sensor.  If the LED lights, then the Hall is bad.

Problem: LED lights, but does not blink or turn off when the engine is cranked.
Solution: Disconnect power immediately!  Your TIM6 is not working properly, is probably overheating itself AND your coil.  The LED should light ONLY when the Hall is in close proximity with the magnet.  Most likely a bad transistor or Hall.  Replace the following components one at a time until it is working as expected: Hall, then the small transistor, then the large transistor.

Problem: LED blinks, but no spark.
Solution: Disconnect the coil.  Connect a voltmeter to the coil connections on the board.  Position the magnet so the Hall sensor is activated, and the LED stays on.  Quickly note the output voltage then disconnect power to keep from overheating your TIM6. The output voltage from the board should be roughly 3/4 of the battery voltage, i.e. if you are using a 6 volt battery, then output should be 4.5 to 4.75 volts.  If you are not getting any readings, then one or both of the transistors on the board are probably bad.  E-mail me if you want replacements.  These run roughly $6 for both, including shipping.  If you are getting a good reading, then test the coil by checking the resistance of the primary and secondary windings.  The resistance should match the coil specifications.  If you bought a coil from us, the specs are on our web page.

If everything seems to be working except you get no spark at the plug, I suggest removing ALL the components from the engine, including the spark plug, and reconnecting it on your work bench.  Make sure you run a wire from the plug threads back to the coil negative (or TIM6 ground or battery negative).  If you get it working on the bench, then reinstall one component at a time on the engine and re-test until you find the fault.

Do you offer complete kits, or completely assembled engines?


We primarily sell plans (thus our web name,  We do offer some supplemental parts that cannot be machined by typical hobbyist (like bearings), and non-metal materials (graphite, Delrin, plexiglass, ignition systems, etc).

Can plans be electronically e-mailed to me?

Yes!  After the first five years that we have been running Jerry's business, we have been impressed with the friendliness and integrity of everyone we have met and done business with. We have come to realize that pirating of our plans would not be an issue with the great majority of our customers. 

We have found an e-commerce site that works well for digital downloads ( and have modified our web site to allow PDF downloads for all of Dad's plans.  Obviously, there are no shipping cost, so you save that, along with a 10% savings since we don't have to use up our ink, paper and envelopes. 

Just click the "Download PDF" button, and you will be directed to a new page to enter your payment.  Select "Paypal" or "Credit Card", complete the payment, and then you will be directed to another page with a download link.  Click the link, and the plans will download to your computer.  You will also receive an e-mail with this link.

International buyers: We highly recommend you use this feature, as USPS shipping cost overseas tripled in early 2013.  Our web site (linked to Paypal) allows only one rate structure by weight, and thus our shipping rates are based on the more expensive "package" rates, not the cheaper "flats" (large envelopes).  So if you wish for your plans to be mailed, the minimum cost is $8.55, but depending on total order weight, could be as much as $20.00

Does the “Material Set” come with everything I need to build my engine?

The short answer is no. 

Generally you must come up with and use your own metal stock. 

Material Sets/Part Kits generally contain items that are usually hard to get or obtain for a reasonable price in a small quantity, i.e. bearings, Delrin (a form of plastic), graphite.  Each engine page describes EXACTLY what is included in the parts kit.