Hour Meter

[John Pasinski]

Has anyone installed an hour meter for their engine? If so, where have you connected it? I'm thinking the run side of the ignition switch so it only runs while the engine is running. I really don't want to tap into that line at the switch though. Suggestions?
It seems more logical to me to go by engine hours than miles between oil changes.

[Rod Run]

Not really more logical because these aren't boats.

If you have 100 hours driving down a highway, it's going to be a lot different than idling 100 hours. Much more different than a combined city/highway average.

What would you be using as your benchmark for changing the oil?

[MARKDTN]

Plug it in at the fuse box to an ignition switched auxiliary. No cutting required.

[LockDoc]

-
^^^^.. What he said. IGN UNFUSED in the fuse box.

LockDoc

[John Pasinski]

Originally Posted by Rod Run

Not really more logical because these aren't boats.

If you have 100 hours driving down a highway, it's going to be a lot different than idling 100 hours. Much more different than a combined city/highway average.

What would you be using as your benchmark for changing the oil?

I haven't thought it out that far yet. I'll come up with some standard. I just feel hours are a more logical gauge as vehicles sit and idle especially in hot weather a lot more than we realize.
I'm also seeing more and more research showing oil is happier with filter changes more often than a complete change. Just my observations......
Leon; MARKDTN..........Thanks for the help

[SS Tim]

An oil pressure switch is the most accurate and switched power is the easiest. So feed it ignition power and ground it through an oil pressure switch.
Run an hourmeter and compare to your odometer. A simple week by week log or fuel log recording mileage and hours will give you a very good feel for adverage mileage vs hours run.

[John Pasinski]

Originally Posted by SS Tim

An oil pressure switch is the most accurate and switched power is the easiest. So feed it ignition power and ground it through an oil pressure switch.
Run an hourmeter and compare to your odometer. A simple week by week log or fuel log recording mileage and hours will give you a very good feel for adverage mileage vs hours run.

That's the kind of detail I like. BUT.......I have an oil pressure line (80#) no switch. Isn't there a battery ground in the fuse panel? Perhaps I can use that?

[Mike C]

The point of wiring it like he says is if the "ign" is on, the Hobbs meter won't be counting hours if the engine is not actually running. The oil pressure ground activates the meter. Otherwise sitting with the key on could cause the meter to run.

[mechanicalman]

Originally Posted by John Pasinski

That's the kind of detail I like. BUT.......I have an oil pressure line (80#) no switch. Isn't there a battery ground in the fuse panel? Perhaps I can use that?

There are other places on a small block to install oil pressure switch (not sure all small-blocks have the same provisions), otherwise you could use a tee like in the picture, just screw your oil line fitting in where the switch is then use a switch like in the picture for your meter.

[Steeveedee]

If you don't drive more miles in the recommended change interval, change the oil quarterly. Example-

If the manual says 5,000 miles between oil changes and you don't drive 5,000 mile in a quarter, change the oil quarterly. The important thing is to remove any crud or condensation that may be deposited or formed due to not driving enough miles (thus getting it hot enough to remove condensation and unburnt gasoline from the oil).

When I worked as a mechanic, I had a guy come in with a five-year-old Monte Carlo. The oil change interval for miles by the manual was 5,000 miles. He hadn't driven it 5,000 miles in 5 years! That oil was sludge, to say the least. He didn't read down to the part where short trips are worse on the engine, and dictated 6 month intervals in those days (IIRC) if the 5,000 miles wasn't reached.

Save yourself a bunch of needless work and expense by following this sort of plan. Note that it is quite conservative, and devised by the engineers to ensure that the vehicle successfully survived the warranty period.

[John Pasinski]

Originally Posted by Mike C

The point of wiring it like he says is if the "ign" is on, the Hobbs meter won't be counting hours if the engine is not actually running. The oil pressure ground activates the meter. Otherwise sitting with the key on could cause the meter to run.

Can I just splice into the RUN line on the ignition switch, and simply ground to the dash?

[MARKDTN]

Originally Posted by John Pasinski

Can I just splice into the RUN line on the ignition switch, and simply ground to the dash?

"run" is power to the coil. If you do that and turn the key on for the radio with engine off you will still be racking up hours.

Yes, you can ground this to the dash with no problems.

I would just change it once a year or 5000 miles whichever comes first.