PS2 Steam engine - takes off too fast at low speeds then goes flying over 20SMPH.... Need Help!

Replace the tach tape with a clean one after cleaning the flywheel off good.  That's likely the problem.

gunrunnerjohn posted:

Replace the tach tape with a clean one after cleaning the flywheel off good.  That's likely the problem.

Thank you John, once again!

Going to order some tape tomorrow and see what happens. I'll follow up if that works.

Daniel,

There is a tach tape somewhere on the forum.  John Will posted it sometime ago.  Maybe if you do a search for tach tape you can find it.  I agree with John, the most probable cause is in the tach tape or reader.  When reassembling the tach sensor make sue you have the recommended clearance.  Try this first. 

Did you say the engine speeds up erratically in conventional mode?  If that is the case, the problem could be different.

bruce

bruce benzie posted:

Did you say the engine speeds up erratically in conventional mode?  If that is the case, the problem could be different.

Cruise works in conventional mode as well as command, the tach tape is needed for either mode.

If you know what the flywheel size is, I can get you tape.   No question on the issue.

Question for the group, why/how does a tack tape go bad?  It seems to be in fairly clean area of the engine.

thanks

Hump Yard Mike posted:

Question for the group, why/how does a tack tape go bad?  It seems to be in fairly clean area of the engine.

thanks

Excess smoke oil can drip onto it for example. I've seen grease on them too. On the homemade paper tapes, they can lose their black color with age if exposed.

Marty Fitzhenry posted:

If you know what the flywheel size is, I can get you tape.   No question on the issue.

Hello Marty - I do not know the flywheel size. All I know is the motor is the same original Pittman motor that was in it when it was PS1 - It is a Premier Scale Daylight 20-3029-1. Don't know if that helps.

How much for tape? My email is daniel.d.carbone@gmail.com

Thanks!

Engineer-Joe posted:

Hump Yard Mike posted:

Question for the group, why/how does a tack tape go bad?  It seems to be in fairly clean area of the engine.

thanks

Excess smoke oil can drip onto it for example. I've seen grease on them too. On the homemade paper tapes, they can lose their black color with age if exposed.

I'm pretty sure this is what happened. It feels very greasy/oily near the flywheel/tach tape and most likely the smoker was overfilled and spilled out all over it while it was in the box. It does smell like smoke oil on the tape... You can see in the pic it looks drenched. I sure hope this is all it is.

you can measure the diameter of the flywheel, just the distance across the flywheel will be diameter.  if you do pie times the diameter  you will get the distance around the flywheel and that would be the needed length for the new tape.  try 3.14 times the diameter for distance around the flywheel.

Daniel,

Flywheel diameters are measured in mm.  27,  27.5,  30,  31.8,  33.7

bruce

bruce benzie posted:

Daniel,

Flywheel diameters are measured in mm.  27,  27.5,  30,  31.8,  33.7

bruce

Bruce,

Thanks. The tools I have on me here are crude as I am not staying at my place this month, but it appears to be 30mm.

As you can see in the photo - the reader leads appear to be soldered in place nice and snug.

-Dan

While you wait for a replacement tape, if you want to experiment a bit get some correction fluid like White Out and touch up the white stripes.  I realize the tape is a bit greasy but I figure it should adhere enough and only takes maybe a minute or two.  Then run the engine and I think you'll see a dramatic difference.  The tach circuit is looking for contrast (black and white) between stripes; your photo looks more like black and gray.

You appear to have the standard 30mm flywheel.  I attached a tach tape image to this post.  If you print this on the gummed labels for shipping at 100% size, you'll have a tach tape.

MTH PS2 New Tach Tape Image.pdf

Dan,

Try cleaning the tape with a cotton ball and a little denatured alcohol.

You will not damage the tape in any way.

bruce

CONFIRMED -

gunrunnerjohn posted:

You appear to have the standard 30mm flywheel.  I attached a tach tape image to this post.  If you print this on the gummed labels for shipping at 100% size, you'll have a tach tape.

MTH PS2 New Tach Tape Image.pdf

John - thank you so much!

Make sure you clean off all the remnants of the old tape and glue before sticking this one on.

stan2004 posted:

While you wait for a replacement tape, if you want to experiment a bit get some correction fluid like White Out and touch up the white stripes.  I realize the tape is a bit greasy but I figure it should adhere enough and only takes maybe a minute or two.  Then run the engine and I think you'll see a dramatic difference.  The tach circuit is looking for contrast (black and white) between stripes; your photo looks more like black and gray.

Brilliant. I did just that - white out over the white spots, black sharpy over the black spots and white-out boo-boos, and just like that - evidence confirmed. It was bad tape. She was running pretty darn close to normal with my quick-fix test and now I'm going to do it right, print the factory pattern and put real tach tape back on.

You guys are great, thank you so much for all of the help. Problem confirmed - Tach Tape stained by smoke oil

Problem fix = new tach tape

DdotCdot posted:

 

stan2004 posted:

While you wait for a replacement tape, if you want to experiment a bit get some correction fluid like White Out and touch up the white stripes.  I realize the tape is a bit greasy but I figure it should adhere enough and only takes maybe a minute or two.  Then run the engine and I think you'll see a dramatic difference.  The tach circuit is looking for contrast (black and white) between stripes; your photo looks more like black and gray.

Brilliant. I did just that - white out over the white spots, black sharpy over the black spots and white-out boo-boos, and just like that - evidence confirmed. It was bad tape. She was running pretty darn close to normal with my quick-fix test and now I'm going to do it right, print the factory pattern and put real tach tape back on.

You guys are great, thank you so much for all of the help. Problem confirmed - Tach Tape stained by smoke oil

Problem fix = new tach tape

And to think I was going to ship this whole engine 3000 miles across the US for a $2 fix...that would have been about 100 times that $$$. Knowledge is so valuable, so thank you all for so generously sharing. The body is so clean, I would hate to think of it having been damaged or dinged in shipping.

danke schön!

danke schön!

gunrunnerjohn posted:

Make sure you clean off all the remnants of the old tape and glue before sticking this one on.

Will do, thanks!

DDOTCDOT, print the tach tape out on an adhesive backed paper like AVERY label paper.