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weeze
01-17-2012, 06:31 PM
my manual says to adjust the valves on my engine every 300hrs. i have 125hrs or so on my mower right now. many have said to do this to keep the engine running good. i saw some videos on youtube and it seems like an easy process to do on your own. do you guys do it on your own or do you take it to the dealer for this kind of maintenance? how much does the dealer charge on average? or is it best to just do it yourself since it's pretty easy to do? seems all i would need to buy is a feeler guage. where do you buy those? does anyone know the measurements the valves are supposed to be at on a 26hp kawi fx engine? i've done all other maintenance myself so far and i'm mechanically inclined. this looks like it would be really easy to do. thanks for any input.

here's the videos showing a vtwin briggs engine and a honda pushmower engine:

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NEW CITY LAWN CARE LLC
01-17-2012, 06:42 PM
It is really simple and your engines manuf. website should have engine specs, etc., and the tools you can get at any tool Store or a local Snap-on or Mac tools guy..

SouthSide Cutter
01-17-2012, 06:44 PM
Napa, Advance Auto, Aut Zone etc.

ed2hess
01-17-2012, 09:23 PM
I am not sure this would be a good place to start working on the insides of the engine. You can screw up badly if done wrong. It should cost less than $50.

weeze
01-18-2012, 12:03 AM
can't really mess it up. i mean you loosen the nut then use the guage to tell you how far to tighten it then tighten the nut back down. pretty simple. did you watch the video? i think that's easier than changing a spark plug almost. :laugh:

weeze
01-18-2012, 12:17 AM
found it on the jd website in the owner's manual

Model Z920A

Make Kawasaki

Engine Model Number FX730V

Displacement 726cc (44.3 cu. in.)

Cylinders Two

Bore 78 mm (3.1 in.)

Stroke 76 mm (3.0 in.)

Compression Ration 8.2:1

Speed, Fast Idle 3600 +/- 100 rpm

Speed, Slow Idle 1700 +/- 150 rpm

Valving OHV

Oil Filter Screw On Type

Cooling Type Air

Air Cleaner Dual Stage Heavy Duty Air Cleaner

Spark Plug Gap 0.76 mm (0.030 in.)

Spark Plug Torque 22 N•m (16 lb-ft)

Ignition Coil Air Gap 0.20-0.40 mm (0.008-0.016 in.)

Valve Adjustment Clearance 0.05-0.10 mm (0.002-0.004 in.)

Richard Martin
01-18-2012, 03:38 AM
Valve Adjustment Clearance 0.05-0.10 mm (0.002-0.004 in.)

Are you done adjusting them yet?

There was a post on this exact same thing a few days ago. The guy had somehow turned a 10 minute valve adjustment into a 4 hour ordeal. Some people.

orangemower
01-18-2012, 08:35 AM
What, no timing wheel? LOL

They are easy to do. Just make sure the valve is closed. You can spin the engine over and watch the rocker arm push the valve open and closed. Just make sure the valve is all the way closed before you make any adjustments.

scagman52
01-18-2012, 10:00 AM
jason...you say you are mechanically inclined but yet you do not no where to buy a feeler gauge. The process is fairly simple but if you do it wrong you end up with bent valves. If you'r not sure I would let the dealer do it especially if it is under warranty

Green Machine Mowing
01-18-2012, 10:21 AM
Did anyone see the spec for them? .002 to .004" Most feeler gauges dont go that thin, OP make sure your does before you buy one and or pop the valve covers. Second if the people who design, manufacture and warranty the engine say 250 Hrs. why on gods green earth would you go at half the interval?

gdguth
01-18-2012, 07:27 PM
How do you adjust the valves on a OHC engine? Is it similiar? I ask because I have a honda with the Over head Cam.

Richard Martin
01-18-2012, 07:34 PM
How do you adjust the valves on a OHC engine? Is it similiar? I ask because I have a honda with the Over head Cam.

Most Hondas use a locknut and screw adjustment. The screw takes a special tool, Honda part number 07708-0030400.

gdguth
01-18-2012, 08:07 PM
What about the time belt, what needs done with it when you adjust the valves? Do you adjust it also. I don't have any knowledge of this. I have major kickback when pulling the starter rope and I have heard before that a cause of this could be valves are out of adjustment, is this true? Sorry to the OP, not trying to steal your thread, just thought of these questions when i saw a post about valves. By the way the engine is a Honda GVC160 OHC.

luis@NJ
01-18-2012, 08:17 PM
If its running good leave it alone :sleeping:

gdguth
01-18-2012, 09:01 PM
If its running good leave it alone :sleeping:

So you are saying even though it wants to yank my arm back when pulling the starter rope, as long as it starts, do worry about it? I don't think this is really good!! You are right it does run well besides that fact.

NEW CITY LAWN CARE LLC
01-18-2012, 09:56 PM
It won't hurt to adjust them, just make sure the valve is fully closed before adjusting clearance...
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luis@NJ
01-18-2012, 11:35 PM
So you are saying even though it wants to yank my arm back when pulling the starter rope, as long as it starts, do worry about it? I don't think this is really good!! You are right it does run well besides that fact.


That is not what i meant. If your recoil is yanking your arm or course you should check it out and fix it. I understood that the manual said to adjust them at xxx hours and you were at half that amount thus me saying if its running properly leave it alone. Did that explain my point better? :waving:

luis@NJ
01-18-2012, 11:40 PM
So you are saying even though it wants to yank my arm back when pulling the starter rope, as long as it starts, do worry about it? I don't think this is really good!! You are right it does run well besides that fact.

You thought i was commenting about your situation lol I was commenting the the thread starters post not yours, :hammerhead:

Ridin' Green
01-19-2012, 12:03 AM
Did anyone see the spec for them? .002 to .004" Most feeler gauges dont go that thin, OP make sure your does before you buy one and or pop the valve covers. Second if the people who design, manufacture and warranty the engine say 250 Hrs. why on gods green earth would you go at half the interval?

Don't know where you are getting yours from, but every set I have had, has gone down to .0015". I have two sets right now that go that small, and they aren't anything expensive or fancy. I agree on leaving them alone until it's time according to your owners manual, or some issue indicates they should be adjusted earlier.

Jason,
if you have an O'reilly's, AutoZone, or NAPA anywhere near you, go to them. They'll have what you need for feeler gauges, and at a very reasonable price.

NEW CITY LAWN CARE LLC
01-19-2012, 12:18 AM
Additionally I would think a manufacterer's recommended service interval would most likely be sooner and/or more frequently than truely needed so performing service before those times is highly unneccesary...
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weeze
01-19-2012, 12:58 AM
i'm not adjusting them yet...i probably will not adjust them until after the 2012 season depending on how many hrs i mow this year. i just like to be prepared ahead of time. i will not adjust them until 300hrs. at that time my mower will no longer be under warranty i dont' think. it's not really about that it's just i don't trust people. i mean when i bought the mower i had them adjust the air intake hose connected to the carb so it wouldn't vibrate against the metal piece on the back of the mower possibly causing a hole in the hose over time. i watched them adjust it before i bought the mower. they did fine but they forgot to tighten one of the bolts on the metal piece back down. (they had removed it to get at the bolt for the hose better) it's just little mistakes like that. who knows what little mistake they could make while working on the engine? :laugh:

the reason i asked about where to get a feeler guage is because i've never bought one before. i've never used one either. i don't think we've ever had the valves adjusted on any engine we've ever owned and we've never had any problems. so who knows? anyways i'm remembering seeing a feeler guage before in my dad's garage. if i can find it i'll just use it. i may practice on my pushmower first since the valves on it have never been adjusted. most feeler guages go as small as .0015 like ridin' said. i figure i'll use .003 since it's right in the middle of the recommendations. i hope it doesn't have some sort of star bit or special type of bit to adjust them. i hate that kind of junk. they try to make everything where you can't work on it yourself nowdays or you have to buy some special tool. i hope it's like the honda engine in the video and i'm able to use two wrenches to do it. has anyone done theirs and know what you use on the kawi fx engines?

jdunk
01-23-2012, 06:17 PM
if it ant broke dont fix it. i would not ajust anything unless you are having a problem
just keep the oil changed and the motor clean and let it go

BigFish
01-23-2012, 07:32 PM
if it ant broke dont fix it. i would not ajust anything unless you are having a problem
just keep the oil changed and the motor clean and let it go

That's the ticket!
More than anything, pull the fan/cyl. shroud on a regular basis and clean around the heads especially around the valve guide casting/opening.

I would/do run straight 30wt oil also, as long as the temps don't get too low. I see yer in Alabama so low temps shouldnt be an issue.
Also, valve adj aren't covered under warranty. So if ya let the dealer do it yer gonna pay.

BigFish
01-23-2012, 11:40 PM
You can download an almost complete ( hey, it's free ) a shop manual here:
http://www.mymowerparts.com/pdf/Kawasaki_Service_and_Repair_Manuals/

It should give you an idea of whats going on.
I like to use individual feeler blades, some feeler guages come apart , if not just snip it off with scissors.

weeze
01-29-2012, 10:29 PM
i worked on my pushmower valves today. the intake valve was perfect and didn't need any adjustment. the exhaust valve was a little loose so i set it right. when i tightened the nut back down i guess i tightened it too much and it stripped out the adjustment screw. :laugh: ordered a new one. they cost about $2.00. those things are so fragile and weak it's pathetic. i'm sure the ones on the kawi mower engines are beefier. the adjusting part is simple it's just on that pushmower those screws are like toothpicks almost. :laugh:

here's a page of valve clearances for honda engines:

http://outdoorpowerinfo.com/engine_specs/honda_valve_gaps.asp

the engine on my pushmower is the gcv 160

there's something i'm wondering. why do they make valves adjustable in the first place? why can't they just make something that keeps them in spec that way they never get loose? instead of an adjustable screw why not just make a metal rod the right length that's part of the rocker arm? that way they would never get out of spec and never need adjusting. i'm no engine expert or anything but just wondering why they make them adjustable when they are supposed to remain at one setting?

Richard Martin
01-30-2012, 01:14 AM
there's something i'm wondering. why do they make valves adjustable in the first place? why can't they just make something that keeps them in spec that way they never get loose? instead of an adjustable screw why not just make a metal rod the right length that's part of the rocker arm? that way they would never get out of spec and never need adjusting. i'm no engine expert or anything but just wondering why they make them adjustable when they are supposed to remain at one setting?

Tolerances in manufacturing is one reason. And parts wear.

grasscutter96
08-19-2012, 10:04 AM
Old subject, but see that OP question was not answered.

Most engines have a 'compression release' lever built into the cam. When this wears out, you will get MAJOR kickback that will just about rip the pull handle out of your hand!

You have 3 options:
1-make sure you pull start it on the compression stroke.
2-make sure valves are set perfectly. (must be done with engine cold. This means sitting overnight.)
3-Replace the cam. (some manufacturers have a replaceable comp release lever. Others need to have whole cam replaced. Either way, the engine is coming apart.)

piston slapper
08-19-2012, 11:02 AM
Grasscutter96....a sheared flywheel key or a cylinder full of gas from a leaking carb...will lengthen your arm also...I had a Honda 5.5hp on my logsplitter that would always kickback if you just yanked the rope...however..if you pulled up on the rope nice and easy..till you started to feel compression..and then yanked it...it never kicked back and always started on the first pull...sometimes its cheaper and less painful to just get along with your eqipment..

Jason...they do have engines that don't need valve adjustments..Kohler Commands...they have hydralic lifters...
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grasscutter96
08-19-2012, 11:24 AM
piston slapper: True that! I did base my answer on the assumption that the engine was in good working order, besides having hard kickback. & yes, the other 2 options you mentioned can cause it as well.

POWDER SL,UT
08-19-2012, 12:46 PM
Almost all of the quality small engine manufactures recommend the valve adjustment at 300-350 hours, but it's really more of a valve inspection. In my experience, usually the valves are still within tolerance at this hour of use range.

I also believe the majority of folks don't even adjust or inspect at the recommended 300-350 hours.

Most likely, you'll just take the cover off and discover with the feeler gauge that it's within tolerance and put the cover back on. If it needs to be adjusted, then you can DIY or pay the dealer, but it cost nothing or any adjusting to close a valve and check with a gauge first.

Note: My experience is if in fact at the actual recommended hours and NOT just at anytime during the life of a small engine.

weeze
12-24-2013, 12:12 AM
found info i needed here:

weeze
12-24-2013, 12:38 AM
my stihl br600 and the kawi fx engines the valves get out of adjustment pretty quickly. it's only been about 100hrs on my stihl and they were loose. it's been 200hrs on the kawi and they are loose.

my honda trimmers and pushmower i checked after 10 years for the first time and they were still perfectly in adjustment.

i guess noone else can figure it out as good as honda when it comes to engines.

next mower i get will have a kohler engine and then that will be the end of valve adjustments. :laugh:

if only honda would make ztr engines and blowers. then we'd live in a perfect world.

Breezmister
12-24-2013, 06:28 AM
if only honda would make ztr engines

Don't know if it's big enough for you......:waving:

http://www.smallenginepower.com/catalog/i229.html

weeze
12-24-2013, 12:54 PM
yeah i've seen those. they are a little underpowered and i don't think they are full on commercial engines. maybe they are i dunno. doesn't look like it if you look at the air filter.

it is the GX series so maybe it is commercial. it's 22.3hp. the kawi i have now is only 23.5hp so not a huge difference. maybe i'll replace the kawi with the honda when the time comes if it's possible to even fit it on my mower. problem is that honda is horizontal shaft. i need a vertical shaft.

what i meant is mowers should come with honda engines on them when they are new or at least have that as an option. a 34hp commercial honda mower engine would be killer!

i found this one but it's only 20hp.

http://www.smallenginepower.com/catalog/i194.html

larryinalabama
12-24-2013, 02:22 PM
I have never had a valve cover off any Kawasaki engine I own, one has over 1300 hours on it.

weeze
12-24-2013, 03:46 PM
really?

i know on the older ones we never did the valves. they were on tractor mowers though.

the one i have now bent a pushrod at 299hrs. they said it was because the valves were out of adjustment. it was replaced for free under warranty though.

i checked the clearance on mine and it was at about .005" on each valve. it's supposed to be from .002" to .004" so they were all a tad loose.

to be honest i think these newer kawi engines are pieces of crap. it's like they are built in china or something. the oil drain thing is rediculous. made of plastic. it's loose already and they said you have to remove the motor to replace it. it's still working but barely. also the oil fill tube is plastic and justs sits down inside the engine block with 1 o-ring to keep oil from coming out. my guess it's only a matter of time before one day oil will start squirting out from the base of the filler tube. one of the tabs on the fan cover broke off in the first season of use.

they just dont' seem to be well made to me. i'm sure the insides are ok but everything else completely sucks.

larryinalabama
12-24-2013, 04:44 PM
My 16 hp with 1300 hours has excessive end play and the starter is starting to clash. Im going to tear it down and hopefully I can just get buy with a 110$ lower case. Your right, I think these engines should last at least 2500hours. I have never had dirty oil in my engine.

Breezmister
12-24-2013, 05:35 PM
yeah i've seen those. they are a little underpowered and i don't think they are full on commercial engines.
maybe they are i dunno. doesn't look like it if you look at the air filter.

What I liked about it was that it comes with a cast iron sleeve.

This is the thing I don't under stand........ How much horse power do you really need ? Here is the thing, we have 5 exmark lazers that have 3 different engines.
A ch25, @ 25 HP... a ch740 @ 27 HP and a fx 801 @ 29 HP. All on 60 inch units.

Is there some kind of mathematical formula with the alphabet thrown in that says you need "x" amount of HP ?

what i meant is mowers should come with honda engines on them when they are new or at least have that as an option. a 34hp commercial honda mower engine would be killer!
i found this one but it's only 20hp.

I think that would be great if they would have the Honda as an option ( ya hear that Exmark ) If I had my way, there would never be a B&S or a large Kawasaki
on any of our equipment....It make me cringe when I see our newest GV leaf loader with the B&S......Time will tell.

weeze
12-24-2013, 10:28 PM
yeah i dunno about the hp and they keep changing the ratings every year so who really knows? my kawi is 26hp but on the newer models it's labeled as 23.5hp. it's the same engine.

my next mower i'm gonna go with a kohler engine. they seem to do better on gas than a kawi and you don't have to adjust the valves.

i think they all last about the same length of time. kawi, kohler, B&S vanguard, etc.

yankdownunder
12-27-2013, 11:04 PM
With air cooled engines, the expansion and contraction in the run/stop cycle is much greater than in a liquid cooled engine.
My experience with A/C engines ranges from VWs to lawnmowers. With VWs, adjust valve every oil change, and use straight weight 30 oil. No ifs, ands, or buts.
It could not hurt to CHECK the valves. Then if they need adjustment, you could bring the valves into spec regardless of mfgr guidelines.
Adjusting valves [if there is a fairly simple lock nut/bolt] is fairly simple. So, why not adjust valves, regardless of mfgr recommendations?
Also, with the leaning of the mix [for emissions] the cooling capacity of the engine to coolitself is diminished. So shortened CHECK intervals would not be out of line.
We used to rely on rich A/F mix to help cool engine. Can't afford that now.