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6'7 330
09-29-2005, 09:42 PM
When we purchase a machine immediately, we install a tiny tach. All our equipment, from 21-inch mowers to 72-inch z-turns gets tached out to 3750 with the blades spinning.
All power equipment manufactures should make a tachometer standard issue, on at least commercial walks and z-turns. But sadly, very few include a tachometer on their mowers.

If you do not have a tachometer on your equipment, I would recommend you installing one.

http://www.tinytach.com/tinytach/index.php

TClawn
09-29-2005, 11:26 PM
I've wondered about that too. they should have a tiny tach where the hour meter goes, and let it run off the battery, gives you the hours when the engine is off, and gives you the rpms while it is on.

btw, I would be afraid to run my equipment at 3750. I've got all of them governed for 3600, and usually run them between 3450-3550.

Envy Lawn Service
09-29-2005, 11:31 PM
Tach came standard on the Lesco Z.
The CrewBoss meter is nice.
Hour meter/Service reminder engine off.
Tach engine on.

Jason Rose
09-30-2005, 12:35 AM
I love the tiny-tach meters too!

My machines that actually have hour meters are the mechinical type and either stop working or get dirt in them and I can't read the numbers anymore!!!

I agree on the rpms as well. I run around 3800 on everything. ( I will push 4,000. But that's my limit!) Thousands of hours logged on several Kohler engines and not a hint of failure.

I had to ORDER one from my dealer when he sells these cheapo hourmeters with no tach for 12 bucks. They all said I was nuts for wanting to spend $45 for a tiny-tach.

Restrorob
09-30-2005, 07:04 AM
If a said engine puts out X amount of hp at a certain RPM I see no point in exceeding that factory specified RPM with the blades engauged. It's just harder on the engine, And I've seen my share blown from this.

alwaysgreener
09-30-2005, 07:07 AM
All my Cub Tanks came with them. They are a must....

6'7 330
09-30-2005, 05:01 PM
All of our most recent equipment purchases, the Kawasaki engines have come set from the factory with the blades spinning 3750.The last several z-turns purchases, we didn’t have to adjust the rpm’s.

65hoss
09-30-2005, 05:56 PM
I put tiny tachs on all machines as well.

MBDiagMan
09-30-2005, 07:17 PM
All Bad Boys come with an LCD hourmeter/tach. It is a nice feature and very helpful in getting the most from your equipment.

Have a great day,
Doc

lawnmaniac883
09-30-2005, 07:27 PM
If a said engine puts out X amount of hp at a certain RPM I see no point in exceeding that factory specified RPM with the blades engauged. It's just harder on the engine, And I've seen my share blown from this.


Restro, these guys arent worried about max power, they are worried about increased blade tip speed. Raising the rpms a hundred or two will, in some cases, significantly increase the quality of cut.

stumper1620
09-30-2005, 08:04 PM
If a said engine puts out X amount of hp at a certain RPM I see no point in exceeding that factory specified RPM with the blades engauged. It's just harder on the engine, And I've seen my share blown from this.
I hear ya,
I had a B/S 18 hp lawn tractor for 9 years when very suddenly it got a rod knock,
tore it down to check it out, rod snaped off about a 1/2" down from the piston skirt. my dealer said that was due to slightly high rpm over the life of the engine. causes stress cracks in the rod. sounded right to me, there was no other reason for that engine to go. other than the failed rod there was nothing else wrong with it.

Restrorob
09-30-2005, 08:07 PM
All of our most recent equipment purchases, the Kawasaki engines have come set from the factory with the blades spinning 3750.The last several z-turns purchases, we didn’t have to adjust the rpm’s.

Thats fine you didn't adjust the rpm's, But all the factories do is slap them together and ship them out. It's up to the Servicing Dealer to check them over and set them up to factory specifications (rpm, Belt adjustments, tracking ect.). If your dealer isn't doing this thats his deal when one comes back with a problem. I was merely stating higher rpm's could cause more harm than good, And just for the record all FB, FD, and FH Kawasakis should be set at 3600 and the FC series set at 3425.
I set ALL new units to factory specs. with blades engauged just to watch out for my backside.

MBDiagMan
09-30-2005, 08:12 PM
Restrorob,

Your contribution here is VERY valuable and VERY appreciated.

I have an FD Kawasaki and it runs about 3450 wide open and blade engaged. Can I simply move the throttle cable, or will it require governor adjustment.

Thanks again,
Doc

Restrorob
09-30-2005, 08:15 PM
my dealer said that was due to slightly high rpm over the life of the engine.

Your dealer was exactly right, A rod breakage close to the piston is indeed a result of higher than normal rpm. So I bet it's a little lower now huh.

Restrorob
09-30-2005, 08:40 PM
Restrorob,

Your contribution here is VERY valuable and VERY appreciated.

I have an FD Kawasaki and it runs about 3450 wide open and blade engaged. Can I simply move the throttle cable, or will it require governor adjustment.

Thanks again,
Doc

Thanks Doc, Actually neither. Here's the procedure page form the Service Manual.
Take Care

stumper1620
09-30-2005, 09:27 PM
Your dealer was exactly right, A rod breakage close to the piston is indeed a result of higher than normal rpm. So I bet it's a little lower now huh.
Ya, that slowed her down some. especially when the other rod let go.
want some parts?

6'7 330
09-30-2005, 09:48 PM
The v-twin kawi’s are rated at 3800 rpm and our last mowers which were Toro’s this year and Exmark's last year came to the dealer, from Toro/ Exmark at 3750 with the blades spinning,Per Toro/Exmark specs.

Our Kohler and kawi twin cylinder engines get set to 3750 with the blades spinning. Many of, our engines have been in service since the year of the Kawi v-twin introduction,with no problems,and a lot of hard hours on them .The flathead Kawi's ,I will agree,should be set no more then 3600.

Envy Lawn Service
09-30-2005, 09:52 PM
Bill is right on the Kawasaki's.... 3800 RPM.

Restrorob
10-01-2005, 12:22 AM
It doesn't matter who's right or wrong guys, I use the on-line Service Manuals
because working for a Servicing Dealer It is my job to set up and repair equipment to factory standards or recommendations. As I said before it's just a sure way no customer is going to bring in a blown engine and say it was my fault because I set it up too high. So until they change the ratings in the service manuals they are the boss.

Take care

MBDiagMan
10-01-2005, 09:37 AM
Restrorob,

Thanks very much for the attachment. It is not clear, but am I safe to assume that this adjustment is done with no load? I assume so, and then the governor maintains the set rpm under load. Is my assumption correct or do I do this with deck engaged? They say fast idle position which I take to mean push the throttle cable to max. speed.

Thanks again for your help,
Doc

Restrorob
10-01-2005, 11:56 AM
Restrorob,

Thanks very much for the attachment. It is not clear, but am I safe to assume that this adjustment is done with no load? I assume so, and then the governor maintains the set rpm under load. Is my assumption correct or do I do this with deck engaged? They say fast idle position which I take to mean push the throttle cable to max. speed.

Thanks again for your help,
Doc

It does state set at no load, But it's best done with the deck engauged to get the rated hp from the engine under load, But try not to run full throttle with the deck disengauged and have someone sitting in the seat as a safety precaution while adjusting. The governor will indeed maintain the proper rpm once set and push the throttle control to the max before adjusting.
See Ya

MBDiagMan
10-01-2005, 01:08 PM
Restrorob,

Thanks a bunch. Maybe I did not print all of the attachment. I only have a half page and I can't find anywhere that indicates no load. No worry though, you have given me what I needed and answered my questions.

The assembly on my mower bolts on a little different from the diagram but I found the bolts and made the adjustment with no load. I set at 3570 no load. It dropped to about 3510 with load. Is it normal for the governor to allow this much speed loss with load?

I am getting ready to leave for vacation and will set it with load when I return.

Again thanks for all the time and effort that you spend helping us here. It is invaluable.

Have a great day,
Doc

TLS
10-01-2005, 01:16 PM
I run my 27hp LC Kawi Lazer at 3810 free load, and with blades on and running I'm at 3760-80. Been like this since new.

On my SCAG with the 14hp Kawi I'm at 3700 free load, and 3650 cutting.

There is a BIG difference in cut quality from 3450 to 3750.

If an engine is free load adjusted to only 3600, your then under your peak power output when mowing, easily seeing the rpms drop below 3400 in thick stuff.

Kohler twins run real nice between 3800 and 4000 once they're broken in.

Restrorob
10-01-2005, 04:40 PM
Is it normal for the governor to allow this much speed loss with load?

Yes Doc it is, I've seen a unit drop a little lower than that but once set with a load the governor will work as needed and properly.

Have a safe and great vacation !
See Ya

6'7 330
10-01-2005, 06:06 PM
I run my 27hp LC Kawi Lazer at 3810 free load, and with blades on and running I'm at 3760-80. Been like this since new.

On my SCAG with the 14hp Kawi I'm at 3700 free load, and 3650 cutting.

There is a BIG difference in cut quality from 3450 to 3750.

If an engine is free load adjusted to only 3600, your then under your peak power output when mowing, easily seeing the rpms drop below 3400 in thick stuff.

Kohler twins run real nice between 3800 and 4000 once they're broken in.
Your 14 is probably a flathead FD series, not a v-twin. Your are correct, keep the flathead's at 3600-3650.Our v-twin's and lc kawi's are set at about 3830 free load, with the blades engaged around 3750-3780.All our newer mowers, have come from the manufacture with the rpm’s adjusted at that setting.

MBDiagMan
10-01-2005, 07:05 PM
I did not realize that there are flathead FD's. My engine is an FD731V liquid cooled vertical shaft engine. That might be why the attachment picture looked different than my engine. Restrorob, I'm sorry if I misled you about the engine that I have, it was unintentional.

So now, what should the rpm be set at on my lc? Is it 3600 as in the attachment or 3870 as 6'7" said? I would like very much to have the extra blade speed, but I do not want to compromise engine longevity by running it too fast.

Thanks for your responses,
Doc

Restrorob
10-01-2005, 10:46 PM
No problem Doc, It was part my fault for not asking for your exact model number. All FD series engines are OHV and the Service Manual states 3600 + - 75 for all, Whether it be Horizontal or Vertical. So going a little over is better than a little under.

Take care