How to install an hour meter for ICE for $5.88

[KentuckyKen]

Just installed a Racing Powersports hour meter thanks to info from Rob_v1 on the “What should be the break-in period be for the Clarity?” thread. $5.88 on EBay, shipping included.
Using Rob’s experience on where to wrap the inductive pick up wire, I then found a mounting location that does not interfere with the removal of the top cover on the engine. So easy installation with no permanent modifications and easy replacement if this cheap Chinese knock off hour meter fails in the future.

So here the process I used:

1 Remove top over to expose spark plug coils.
Tip: You will see 2 posts in rear poking up through the rubber grommets and there are 2 hidden under front of cover. Just pry/pull upwards. (use a q-tip and apply a tiny amt of silicone grease to posts and it will come off much easier in the future)

2 Remove the wire harness from the coil on the second from right.
The right most one is too hard to see the slot you have to fish for wire through.
This is to make it easier to wrap the wire around the coil. Tip: Use a small screwdriver to gently pry up tab on top while pulling off harness.

3 Wrap the wire around the coil leaving enough to reach one inch past the end of the metal bracket just to the right of where the top cover was.
This is where the meter will mount and the wire must run the full length of the meter. I was able to get it to go around 5 times. This is a bit of a challenge since you have to fish the wire through a slot between the coil and the bolt/post that holds the coil in place. Patience and needle nose pliers are helpful. See picture.

4 Make sure the wraps of the wire around the coil are tight and secure them.
I used self fusing silicone tape ( orange in the pix) so it will never come loose.

6 Replace the wire harness you removed. It snaps into place.

5 Attach the end of the wire to the full length of the slot on the bottom of the meter.
Push in gently with tip of screwdriver.

6 Mount the meter to the metal bracket.
See pix. I used some good double sided foam tape I had lying around.
Tip: Clean bracket and meter with rubbing alcohol for good adhesion. I had to pull the small hose on the right side of the bracket about 3/8” towards me from its clamp by the bracket so meter would not rub on the hose.

7 Replace top cover and you’re done!

Note that the ICE will have to run for 6 min for first reading to appear (0.1hr).
Thanks to Rob for telling us where to wrap the inductive wire and that it works there. Took me about 20 min and most of that time was getting the wire around the coil. First time ICE will crank up is a trip tomorrow. Will post what happens and what meter reads.

 

[Hi.Ho.Silver]

Thank you. Awesome instructions and pix! I used to work on my cars a lot but I haven't needed to change a spark plug in many years so I have never seen this setup with individual coils before. (It's been a long time since the "Points, Plugs & Condenser" tuneup) I got the same meter from Amazon ($5.99) and with your great pictures and instructions I will install it after you are able to declare total success. I wish there was a simple way to get this meter to show the ~9 hours my ICE already ran.

 

[KentuckyKen]

Thanks for the kind words. I will know for sure tomorrow when I use the ICE for the first time. All I have to go on now is Rob_v1’s post that this works when wrapped around the coil. I can only take credit for finding a convenient place to put the meter.

 

[Rob_v1]

Oh ye of little faith! My counter is now up to 0.9 hours, following a round trip journey to the airport last night that exceeded the EV range. Very nice write up, Ken! I was too lazy to route it anywhere outside the cover over the plugs, and it may look less suspicious, should the dealer ever look under the hood.

 

[KentuckyKen]

All credit to Rob for paving the way for he rest of us.
I don’t mind it showing and if I ever have a warranty problem with the coils/ignition I’ll have to remove all traces of it anyway. Shouldn’t be a problem.

 

[jdonalds]

Thank you. Awesome instructions and pix! I used to work on my cars a lot but I haven't needed to change a spark plug in many years so I have never seen this setup with individual coils before. (It's been a long time since the "Points, Plugs & Condenser" tuneup) I got the same meter from Amazon ($5.99) and with your great pictures and instructions I will install it after you are able to declare total success. I wish there was a simple way to get this meter to show the ~9 hours my ICE already ran.

I did the same thing on my boat which didn't have an engine hour meter. However the data was available by reading out the contents of the ECU. My boat had 67 hours on it when I installed the meter. I just put a label on the meter with "+67 Hours".

This seems like a good idea for the Clarity too. My car is saying it should be taken to the dealer in three months. Our ICE has run so seldom that I'll guess it has less than 5 hours on it. I think it would be a waste of money to take it in with less than 50 hours or one year.

 

[KentuckyKen]

Whose da man!
Whose yo daddy!
Who let the dogs out!
ROB_v1 that’s who!!!!!!!!!
Rob, installing hour meter as you suggested by wrapping wire around one of the spark plug coils worked like a charm. Meter started at 0 and read 0.6 after 67 mile HV trip and 1.2 hr after returning home (burned 2.2 gal). Good thing I installed it since the ICE was so quiet I could just barely, barely hear it. No high revs heard as some have reported.
Thanks again for showing me how to get it to work with no spark plug wire showing.

 

[Lagreat]

I installed the same meter this afternoon on my car. As the battery was dead, I planned a trip of about 40 miles where I used HV Charge mode to charge battery and let the engine run. After returning home I can see that the meter shows 1.0 hr.

What is the equivalent conversion when engine has run 60 minutes? I liked Ken/Rob’s idea to see how much the engine has been used but would love to hear your thoughts on conversion factor.

Plan to go to Menlo Park event for a question or two I have that are mostly answered on this great forum, however want to see how Honda genius (apple term) can answer that.

 

[Rob_v1]

Not sure what you mean by conversion factor. The meter records accumulated time where an HV spark is detected at the top of a spark plug. So it only records time when the engine is running, in tenths of an hour. And of course 0.1 hours = 6 minutes. Did I miss something?

 

[Lagreat]

I could’ve been more clearer, sorry @Rov_v1.
What I’m looking for is what will the hours translate to?
Do you change oil after n number of hours. Normal yearly or half yearly what ever is noted in maintenance should be the norm, I gather.
How can we tell how many miles the engine may have run looking at the hourmeter? That is what I was referring to when I mentioned conversion factor. However, what do you or others on this forum use that hourmeter count for?
New car, new stuff to learn, as always.

 

[Hi.Ho.Silver]

I could’ve been more clearer, sorry @Rov_v1.
What I’m looking for is what will the hours translate to?
Do you change oil after n number of hours. Normal yearly or half yearly what ever is noted in maintenance should be the norm, I gather.
How can we tell how many miles the engine may have run looking at the hourmeter? That is what I was referring to when I mentioned conversion factor. However, what do you or others on this forum use that hourmeter count for?
New car, new stuff to learn, as always.

Good question. I also installed an hours meter. I would change the oil every 100 hours or 12 months whichever comes first. However, we might need to follow whatever the Clarity’s computer directs us to do in order to not risk a possible warranty issue.

 

[Steven B]

An hour meter could not accurately reflect engine/oil wear. I've always suspected that Honda's Maintenance Minder probably is based on engine total revolutions: RPMs x Minutes running. And I suppose it is even possible the system gathers ambient conditions and factors that in as well. An hour meter reporting 100 hours at 3000 RPMs at 50F is much less severe than 100 hours at 5000RPMs and 90F.

 

[KentuckyKen]

I could’ve been more clearer, sorry @Rov_v1.
What I’m looking for is what will the hours translate to?
Do you change oil after n number of hours. Normal yearly or half yearly what ever is noted in maintenance should be the norm, I gather.
How can we tell how many miles the engine may have run looking at the hourmeter? That is what I was referring to when I mentioned conversion factor. However, what do you or others on this forum use that hourmeter count for?
New car, new stuff to learn, as always.

Honda states to change oil when Maintenance Minder indicates or 12 months whichever comes first. I feel compelled to follow this during the warranry period to avoid any potential problems if warranty service is required.
However with most of us using mostly EV miles, this will probably occur before necessary if MM goes off before 12 months. It depends on what parameters it’s tracking. Honda doesn’t explicitly say what they are. Manual just says according to engine operating conditions and oil conditions; whatever that may include.
On my old CRV there was a count down % of oil life. On my Clarity I only get a count down of months to next service. Dealer service dept told me it’s according to engine temp and time or distance, with short trips (more cold starts) and high temps/rpms weighted more (Take that with a grain of salt, but it makes sense).
But in the PHEV Clarity is it, among other parameters like temps, according to engine running time (great), HV miles (good), or total miles (worthless)?
Nobody knows for sure. Only sure thing is that all the major oil brands say change at 1 year no matter how many miles they say their oil is good for and hedge themselves by adding always follow mfg recommendations. And Honda says don’t go over 1 year. Well just have to wait and see if our MMs go off in under a year or not.

Here’s all I could find from Honda:

• Do not exceed the recommended maintenance interval. Oil eventually deteriorates and loses its ability to protect your engine, due to heat, friction, and exposure to exhaust components. Engine oil contains special additives to enhance the oil's performance, and these additives are also broken down or consumed with distance and time. Engine damage can occur if the proper maintenance schedule is not followed. (Well duh!).

It’s impossible to convert hours to miles exactly (although the car’s computer could easily if programmed). I guess you could pick an average speed on the high side of your driving, multiply, and get an upper maximum milage but it would only be an approximation or limit. I installed the hour meter just so I could know when and for how long the engine is running since I have not got the angry bees/high rpms and with windows up can’t tell most times when it’s running. I usually catch it after the fact by noticing that the HV range has dropped a little and sometimes I catch it on the energy display. I’m just curious as to when it comes on and off, and for how long it comes on since I’ve only found the engine warm and never blazingly hot. I’m sure that counting only HV miles (with occasional System Checks), I’ll time out at 12 months long before I’ll time out at any reasonable oil change milage where the engine was on.

What I’d really like to know is the engine rpm. I’ve found some cheap inductive rpm gauges but can’t find a easy way to get the wire through our high tech firewall. Anybody that’s found a way please post. I’d really like to have an rpm guage.

 

[Rob_v1]

Has Honda published the factors used to determine oil life? The statement in the manual is pretty vague. I found this FAQ about the Volt interesting, and apparently GM did publish the components of their oil life calculation (see item 3 in the FAQ). I was surprised to learn that the approved change interval could reach two years, for the Volt. I didn't see cycles in the algorithm, but I wouldn't be surprised if that was a significant factor in oil life. If, on each trip, the engine starts once, but never warms up (a possible scenario), both oil life and engine wear might be affected negatively. In the Prius, fuel contamination of the oil can be a problem, partly because the engine runs intermittently.

I haven't yet tried using my Scangauge with the Clarity, but it may be able to read engine RPM.

 

[KentuckyKen]

Great link Rob!
I have yet to find an official Honda source for how the MM calculates oil life and I would hope that it was adapted for the unique characteristics of the Clarity.
But given the HV range miscalculation problem and the “aerodynamic” wheel covers being backwards on the passenger side, I’m not getting my hopes up.
My MM is saying maintenance due in 9 months which is 11 m after purchase and with only 1.5 hours on the ICE.

Please let us know if the Scangauge works.

 

[Rob_v1]

Yes, it displays engine RPM. Once I get the firmware updated, it may show several Honda-specific values.

 

[KentuckyKen]

Fantastic Rob. Please keep us posted and with pix.

 

[RoysHonda]

Can you guys recommend a ICE hour meter that can have the internal battery replaced? I read from reviews that the "Racing Powersports hour meter" does not have that, and would have to be replaced. The replacing isn't a big deal, but having the hours reset would be a pain.

Opinions? Thanks again!

 

[KentuckyKen]

Haven’t found one that said it would retain the hours when swapping out the battery. At this price, a new unit is just a few bucks more than a new battery. And the inductive wire slides in a channel so it’s as easy to replace as installing a new battery.
I keep a written record of the hour change so I can add to total hours when it dies.

I would be willing to spend more on a nicer unit that also displays rpm and has a replaceable battery, but I can’t find an easy way to run the wires through the firewall. You can find these on eBay too.

 

[RoysHonda]

Haven’t found one that said it would retain the hours when swapping out the battery. At this price, a new unit is just a few bucks more than a new battery. And the inductive wire slides in a channel so it’s as easy to replace as installing a new battery.
I keep a written record of the hour change so I can add to total hours when it dies.

I would be willing to spend more on a nicer unit that also displays rpm and has a replaceable battery, but I can’t find an easy way to run the wires through the firewall. You can find these on eBay too.

Thanks for the quick response! I just ordered it from Ebay, so its here when the car gets into the dealership for pickup.