Inexpensive 2 Cyl. Tachometer review (On-Going)

[jbuote]

Hey All!

​I've seen many posts from people saying they don't have a tach to check WOT range. For timing purposes, Prop testing etc...
Well, I don't either... So...

​I have a 1971 Johnson 50 HP Hydro-Electric. It was non running when I got it. I've since fixed it up so it runs, and spent an afternoon on the lake with it fishing.
​Had some issues with a misfire, so checked again, and found a crack in the #1 cyl coil.. I've ordered that. I've also decided I need a new prop!
​Existing one is banged up pretty good, and I do believe the hub has spun.

​With all that in mind, I ordered the coil, and an inexpensive Tach that I know I'm going to need to get things right. Especially when prop tuning to get the optimal prop.
I don't expect the coil to arrive until about July 3rd, but the Tach/Hour meter arrived yesterday.

So that's the back-story.. Now to the reason for this post.

​Figured I'd start an ongoing review for this inexpensive Tach/Hour meter I bought here at iBoats and give an ongoing review of how it works/doesn't for my application. Maybe it'll help others if facing an "I don't have a Tach though" issue..

The Tach/Hour meter I bought can be found here:
http://www.iboats.com/Hour-Tach-Met...969931--session_id.219585622--view_id.1186148

​Here it is as arrived:


Continued in next post.....

 

[jbuote]

Now, this Hardline model # HR-8061-2 Tach/Hour meter WILL NOT work on an engine with more than 2 Cylinders. Pretty sure I read they have others that will work with over 2 Cylinders if you're interested when this is over.. LOL

Anyway,
​Here's everything that came in the package with it:


​The Tach/Hour meter, the inductive wire, 2 mounting screws, Sticky tape, a zip-tie, and a log book. Oh, and the obligatory Hardline stickers.. hehe..
​The inductive wire is meant to wrap a few turns around the plug wire it seems, and is only a few feet long, so I'm going to have to find a place inside the cowling to mount this. Certainly not long enough to get to my drivers panel. That's ok though. I wasn't looking for an "At Drivers Seat" Tach/Hour meter for now anyway.
​I like the fact that it's inductive and does not require power form any external source. Suits my testing needs perfectly in that regard.

​It states not to mount it anywhere where temperatures will exceed 125? F, so I have to watch that...

​Seems to have an internal battery though... Pic above shows the display is on and I can navigate the settings.. It shows Hours in use, Tach, Max RPM. with clicks of the single button on the front.
Looking at the back though:


​It seems sealed, with no way to replace the battery it must have should the battery die..

(Continued in next post..)

 

[jbuote]

One thing I do like, as simple as it is, is that it came with the little log book:



​First page you can write in the make, model, year and any notes.. Then, log entries.. Headings are: Hour Reading, Date, Service Performed.
​I was thinking of making a little service log for myself (Easy enough to do), but this little tach came with one.. Ok, I'll take the small things.. LOL

Now I have to set it up.. It can be set for 2/4 stroke, and pulses/revolution.. Will set those when I Install..

​I have to run my engine soon anyway.. It's sat for almost 2 weeks now, and I really don't like it sitting that long without running, so maybe I'll hook this up temporarily for some initial functional checks when I run it before the new coil comes in..
​At least then I can know if it's really reading anything on the inductive wire or not.. I won't count on any readings until the new coil comes in though.. After all, it's #1 that is missing spark, so the RPM reading would be off..

​Well, That's about it for now.. Will update this as I go, good or bad, and maybe this can help somebody someday....

For what it's worth..

 

[82rude]

This review could be really helpful for those that have been thinking about that type or for those that have been recommended to get one.Though i have a nice faria tac thanks for the effort.

 

[Fed]

"All engines up to 2 cyl" makes no sense at all.
Maybe they lost something in the translation?

 

[jbuote]

You know what Fed? You make an Excellent point!!! LOL

​So I did some more reading and thinking on this, and the available settings for this model of the hour/tach meter are:

?1P:1r? indicates that the meter is set for 1 Pulse per 1 revolution.
?1P:2r? indicates that the meter is set for 1 Pulse per 2 revolution.
?2P:1r? indicates that the meter is set for 2 Pulse per 1 revolution.
If your RPM reading is double what it should be at idle you need to select ?2P:1r?

​Other models of this meter go up and have 4p:1r, 6p:1r etc... This model maxes out at 2p:1r

​Please note that this unit isn't marketed strictly for Marine outboards, so I'm guessing there could be some cases of a 2cylinder engine having a single coil and a distributor cap. (Motorcycles, tractors, etc....)
​I bet the claim of "Up to 2Cyls" is to cover them if the inductive wire is attached to the single coil of an engine with a distributor feeding multiple cylinders...

​In reality, if using this on a single cylinder, and set to 1p:1r then it wouldn't really matter how many cylinders (each with it's own coil) the engine has would it...

​Interesting...

 

[Sea Rider]

When ordering Hardline Hour-Tachs need to know fully in advance number of cylinders OB has....



Installed a 8061-2 tach on a 1cylinder OB, when the spark firing was set at 1 pulse per revolution read double count, finally was set at 2 pulse per revolution to read right, don't ask me why read so....

Happy Boating

 

[jbuote]

I apologize for the delay in updating this review... Some "Life" situations have taken priority for now..
​Should be able to continue sometime next week though...

​I was at least able to run my engine for a few... I hate letting it sit for any prolonged period of time.. Just didn't have the time to test this tach yet...
​Had to just start it and run for a few.. That's about all the time I had for it.. LOL

Sea Rider : Thanks for that tidbit... I'll keep an eye on that and post the settings I need to use when I do finally get to it.. I appreciate that info!!

Joe

 

[gm280]

jbuote, as an inductive setup per only one spark plug wire, how would the tach know if that was one cylinder or multi? I mean if it is reading just that one cylinder every revolution, it could be a 12 cylinder engine and read the RPMs correctly. So the option to be every revolution vs every other revolution tells me it works for both 2-cycle and 4-cycle engines regardless of the number of cylinders. But that is just my warped thinking. :noidea:

 

[Sea Rider]

The 8081-2 model was ment for 1-2 cylinder OB's on larger 3 up cylinder OB's must select number of cylinders firstly and then set the spark/pulse to work right. Haven't installed a 8081-2 model on a 3-4 cylinder OB as to know what kind of rpm read outs will be displayed.

Happy Boating

 

[ondarvr]

jbuote, as an inductive setup per only one spark plug wire, how would the tach know if that was one cylinder or multi? I mean if it is reading just that one cylinder every revolution, it could be a 12 cylinder engine and read the RPMs correctly. So the option to be every revolution vs every other revolution tells me it works for both 2-cycle and 4-cycle engines regardless of the number of cylinders. But that is just my warped thinking. :noidea:

​Yes, this is a bit odd, and some 4 strokes fire once per revolution and other fire every other, so you need the switch.

 

[jbuote]

Hey there gm280 !!
Yeah... thought about that..

​@Fed eluded to that in post #5.. Thought about it in post #6.. I think the packaging is just covering themselves for simple installations, plus ability to sell a slightly more expensive tach/hour meter for more than 2 cyls.. I think it's really just marketing In the long run.. LOL

 

[jbuote]

So an update to this review..

​I finally got to install the tach/hour meter this past Sunday.. I installed the new coil that arrived too, so I installed both at the same time.

​When I started up the engine, the tach was reading 2440 rpm.. This was on the 1P1R setting.
​Seemed a bit high, so as per post #7 by Sea Rider , I change the setting to 2P1R.. As expected, it now read 1220...
More like it.
​However, it sounded to be running at a higher RPM than 1220..
​My next step in this review, is to see if I can get hold of/borrow/rent some kind of tach that doesn't require spark pulses.. (i.e. photo sensitive or something where I can put a reflective line on the flywheel and have it determined that way.. )

I've seen several inexpensive ones, but worry about accuracy..
Any suggestions there?

​Anyway, I'm convinced I should have it set at 1P1R since it's on a single cylinder, with an independent coil, so it should only have 1 pulse per revolution..

​As for the review, I'm pretty impressed.. The rpm readings I got didn't jump around at all.. it was steady.. As the rpm dropped (slightly) while warming up and coming off the start lever, the display dropped smoothly..

​So far so good with this tach unit. Just need to find a way to verify RPM's so I can ensure I have it set right..

Till next time!

 

[gm280]

So an update to this review..

​I finally got to install the tach/hour meter this past Sunday.. I installed the new coil that arrived too, so I installed both at the same time.

​When I started up the engine, the tach was reading 2440 rpm.. This was on the 1P1R setting.
​Seemed a bit high, so as per post #7 by Sea Rider , I change the setting to 2P1R.. As expected, it now read 1220...
More like it.
​However, it sounded to be running at a higher RPM than 1220..
​My next step in this review, is to see if I can get hold of/borrow/rent some kind of tach that doesn't require spark pulses.. (i.e. photo sensitive or something where I can put a reflective line on the flywheel and have it determined that way.. )

I've seen several inexpensive ones, but worry about accuracy..
Any suggestions there?

​Anyway, I'm convinced I should have it set at 1P1R since it's on a single cylinder, with an independent coil, so it should only have 1 pulse per revolution..

​As for the review, I'm pretty impressed.. The rpm readings I got didn't jump around at all.. it was steady.. As the rpm dropped (slightly) while warming up and coming off the start lever, the display dropped smoothly..

​So far so good with this tach unit. Just need to find a way to verify RPM's so I can ensure I have it set right..

Till next time!

It could be that the 1220 rpm is correct. What you are looking for is a photo tach. Maybe a local auto parts store has one you can use or rent. Even a correct up type tach would work to verify yours.

I use to have a photo tach to us on model airplane engines. It read the RPMs from the prop. And you had to set it for two blades or three. But it worked very well. Check to see if you have a modelers club in your area. I bet one of those guys would have a photo tach you could borrow.

I also have a strobe tach. It works by adjusting the strobe speed until the object you are testing looks like it is totally stopped. Then you read the dial for the RPM speed. It is an old tube model that is not produced anymore, but really neat to tach fan blades or any spinning object without connecting anything to the object. JMHO

 

[jbuote]

I use to have a photo tach to us on model airplane engines. It read the RPMs from the prop. And you had to set it for two blades or three. But it worked very well. Check to see if you have a modelers club in your area. I bet one of those guys would have a photo tach you could borrow. JMHO

​Hey gm.. I was thinking of checking the local auto parts shop to see if they have a rental/loaner...

​I use to fly R/C planes all the time.. I've let my AMA membership slip years ago though.. Went to Full scale flying.. lol...
​I wonder if I have my photo tach I used on the models.. I remember that.. I had one and yeah.. had to select blade count..
​Did you ever try yours on an outboard when you had it?
​Worth a shot if I can find mine.. lol

Thanks!!!

 

[gm280]

​Hey gm.. I was thinking of checking the local auto parts shop to see if they have a rental/loaner...

​I use to fly R/C planes all the time.. I've let my AMA membership slip years ago though.. Went to Full scale flying.. lol...
​I wonder if I have my photo tach I used on the models.. I remember that.. I had one and yeah.. had to select blade count..
​Did you ever try yours on an outboard when you had it?
​Worth a shot if I can find mine.. lol

Thanks!!!

No my R/C days ended about the time I got into fishing. So even though they were close, I didn't check the outboard with the photo tach. I actually had a built in helm tach on the Bass Boat I had. And since it was all brand new, I really had no need for one. :sorry:

However, the photo tach can be used on the flywheel if you can use some light colored (or dark whatever the best contrast would be) masking tape as a contrast to the actual color of the flywheel. It will work perfectly because it triggers on the different shades or colors. If you get to use one, you can split the flywheel into four equal quadrants and use a contrasting tape on the diagonal quadrants to mimic the prop. It will read direct with that setup like a standard two bladed airplane engine prop as well. Easy peasy! :smile:

 

[jbuote]

Figured I'd post a quick update.. I haven't forgotten about this review..
Just haven't been able to check it out any further..
​Found a grounding issue that is being fixed.. (headache, but that's another thread.. lol)

​Anyway, My Fianc?e was cleaning out a closet today, and she actually came across my old Tower Hobbies digital (optical) tach I used to use on the R/C planes!!
​
​Once I get the ground lug on the engine block fixed, I'll be able to verify (best I can) the tach readings...
​Hopefully, I can get to all that this weekend!
​Would love to take the boat out for a test on the lake Sunday if I can!! LOL

Till later!!

 

[Silvertip]

That tach also will work on an engine ignition system using a "wasted spark" configuration (two pulses per rev for example on a two stroke).

 

[jbuote]

That would explain why in some applications you'd need to use the 2P:1R setting as was mentioned before.. Thanks Silvertip!

​So grounding issue was finally fixed.. Never made it to the lake today, but she runs a bit better now..
​
​The tach however? Ehh.. It started jumping all over the place to where I really couldn't tell what it "Thought" the engine was running at..
​Thinking I need to find a better way to keep the sensor wire isolated so it doesn't pick up anything it shouldn't..
​Not sure about that, but for the purpose of this review, that's what I'm looking at now..

​Tried the optical tach my Fiancee found, and it jumped a bit too.. I think I need to mark the flywheel with something more contrasting, and try it again..

​Anyway, I'll update more as I get it figured out..

 

[gm280]

That would explain why in some applications you'd need to use the 2P:1R setting as was mentioned before.. Thanks Silvertip!

​So grounding issue was finally fixed.. Never made it to the lake today, but she runs a bit better now..
​
​The tach however? Ehh.. It started jumping all over the place to where I really couldn't tell what it "Thought" the engine was running at..
​Thinking I need to find a better way to keep the sensor wire isolated so it doesn't pick up anything it shouldn't..
​Not sure about that, but for the purpose of this review, that's what I'm looking at now..

​Tried the optical tach my Fiancee found, and it jumped a bit too.. I think I need to mark the flywheel with something more contrasting, and try it again..

​Anyway, I'll update more as I get it figured out..

You could always put some contrasting colored tape on the flywheel that contrasts with the flywheel color. But it has to be enough width to allow the optics to pick it up. And then use some light so it reflects to the tach. And you have to put the tape at 180 degree areas as well. But the photo tach will trigger on it and display the RPMs very well. Try it! JMHO