OutdoorKing Repair Forum Forums Repairs and Maintenance Questions On Ride On Mowers Questions On Cox Ride On Mower Frames Cox 11hp, what year model is it ?

bought this mower last week & wanting to know what year model it is ? has an 11hp honda motor.



have had one problem with it.mowed great for about 1/2 an hour then the revs slowly dropped & stalled,wouldn`t start until i let it sit for about an hour.cleaned the plug & fuel filter & ran fine again but then did the same thing.pulled the plug & it was nice & clean,same with fuel filter.

checked the oil which needed 300ml,could this have caused it to over heat ?

many thanks
jason

Hi Jason, welcome to Outdoorking. First, the symptoms you described for your engine are typical of overheating, especially if due to low oil level. So far as your 300 ml figure for how much oil it needed is concerned, are you aware that Honda screw-in dipsticks, unlike Briggs screw-in dipsticks, are required to be read with the thread completely unscrewed? If you weren't aware of that, your 300 ml estimate for how much oil it needed will be a long way short of reality. Incidentally what you have done has caused more damage to your engine than several years of normal use.

Briggs engine numbers include the year of manufacture, but as far as I currently know, Honda ones do not. If you post the full serial number including prefixes etc for your engine, I will see what I can find out about it, but it probably won't include a date. If you post the actual model name and serial number of your Cox mower, someone may be able to estimate the date from that.

hi grumpy, thanks for the quick reply. i wasn`t aware of how to read the dipstick, just took approx another 200ml of oil. lesson learnt,don`t believe seller that just had oil change & oil is full.

engine no is - gv400 2055406

mower is cox automatic variable speed 11hp 410cc

model no is - 09f3 ww

serial no is - h11e 697

cheers
jason

The Cox 09f3 Compact Tractor was manufactured from June 1983 to February 1986. Here is what they call the owner manual for it (it is combined with an illustrated parts list):
http://www.coxmowers.com.au/files/cox/pdf/09F3%2009B6%2009J6%2009M7%20OWNERS%20MANUAL.pdf

There are quite a few different models of GV400, we would need the four letter "engine code" to tell which one you have. All of them were made only in Japan. Here is the owner manual for the engine:
http://engines.honda.com/pdf/manuals/3189120.pdf

Note that its oil capacity is 1.2 litres. I am surprised that it would seize up repeatedly with 0.7 litres remaining in it: there may be another problem as well as the low oil. I suggest you check for grass or other material (such as an insect nest) inside the cooling air cowl. If the air passages are clear, you may have been overloading the mower or operating on an excessive slope.

thanks again grumpy,for the links & your help.

don`t think i was overloading the mower & the area i mow is pretty much flat,i`ll check for any obstructions in the air cowl.

where on the motor will i find the engine code ?

cheers
jason

The GV400 serial number location is shown in this drawing from the workshop manual.

The reason I want you to check the flow of cooling air, is that repeatedly seizing up the engine is very bad for it, so it's better to check the air flow on a "new" (to you) engine when you first get it.

Hello Jason & grumpy,
I have a question: How full was the fuel tank when it was cutting out?
One of mine stops from time to time if im on a bit of a slope (tank side down).
Also cuts out if the tank is low, but not empty.

that`s where i got the gv400 2055406 number from,that`s the only number that`s there.

i don`t think i`ve described the symptoms too well,the motor wasn`t seizing up it was more like it was running out of fuel.could the over heating have been boiling the fuel causing it to cut out ? i had this happen years ago in my hk

g`day mark, tank was about 2/3 full at the time & yard pretty much level

Jason, there is usually a first line with the model and serial number, and right underneath it a separately stamped four letter engine code.

After the engine flamed out, you probably tried to restart it immediately. Did it crank at normal speed, or sluggishly?

ok i`ll re check where the numbers are.

engine cranked at normal speed just wouldn`t start.

cheers
jason

That doesn't sound like it was seizing then Jason. More likely overheating (perhaps due to obstructed cooling air flow) or an engine fault, which could be for example, insufficient tappet clearance, fuel vaporising in the hose from the tank to the carburetor, high temperature breakdown of the ignition module, or restricted flow through a gummy main jet. If it wasn't seizing, chances are no additional harm has been done by you operating it the way you did. What was the day temperature when all this happened?

You can work your way through those items one by one. Is the fuel hose from the tank to the carburetor running downhill the whole way? You could try disconnecting the fuel hose at the carburetor end and running fuel into a cup, to see whether it runs full stream, or the flow is restricted.

To check the ignition module, there are two things you could try. First, when it cuts out, immediately clamp a known good spark plug to the engine with the plug lead connected to it, and crank the engine, watching for a steady stream of blue sparks across the plug gap. If you don't get them, leave the spark test set up, let it cool off, and try it again. The second test you could do on the ignition module is to measure the primary and secondary resistances, with a volt-ohm-meter. However this may not show anything unless the module is misbehaving at the time you do it.

The tappet clearances should be checked, as described in the owner manual. If you want more information on that, just ask.

After those tests, the next step would be to remove the carburetor and clean it with carb cleaner. I can help you through that if you wish.

thanks again for the detailed reply grumpy.have degreased & cleaned the entire motor & definately no other numbers on the engine than those quoted previously.

have had the carby apart & cleaned it all,there was a bit of gunk in there but it wasn`t too bad.it started first go & sounded the best that it has but wont be doing any mowing until monday,will report back then.also the cooling cowl was nice & clean,no built up grass

one other thing i want to ask about,is that the mower moves faster in reverse than it does going forward,is this just a matter of adjusting the drive disc ?

many thanks
jason

The Engine Type designations for GV400 over the years were ADAA, ADAB, ADJB, and ADJD. For the GV400K1 the designations were ADAA, ADAB, ADJB, ADJD, BDJJ and BDJM. The Engine Type designation must be on the engine somewhere. As I said before, all of them were made only in Japan.

If you go to Item 8 in the Maintenance Instructions (right near the back of the owner manual) there are detailed instructions for adjusting the clutch plate, which they say will be necessary periodically as the clutch cone wears. I'd say you need to attend carefully to that adjustment before you look further for the source of that problem, especially in view of the possibility that the previous tenant messed up the adjustment.

thanks grumpy,will have another look for the engine designation,as you say must be there somewhere.

thankyou for pointing me in the direction of the clutch plate adjustment.

cheers
jason

would this engine have a low oil protection switch ? the one on my honda engined compressor in work truck played up a while agao , it too would cut out when hot (no low oil it was full 1st thing i checked) and on a long weekend too !! so disconected it and all was good , took it in for repaires asap

The GV400 has pressure lubrication, so it would probably have an oil pressure cutout if anything rather than a low oil switch. However I cannot find any oil-related auto shutdown feature mentioned in the workshop manual or on the internet. Nevertheless I suppose it is just possible that the engine has been retrofitted with an Oil Alert - it appears some of the G400 engines, the horizontal crankshaft version, had them. It isn't clear why it would run for quite a while, then stop, but would restart after waiting half an hour, if the problem were a low oil cutout that was working properly - but having said that, a low oil cutout that wasn't working properly could be a different story.

Incidentally Jason, from the serial number your engine would be a GV400K1, the later form of the engine, not a GV400. Any GV400 with a serial number beginning with 1 is an early type, and all serial numbers beginning with 2 are K1.

cut the lawns today,mower was running beautifully until about the 45 min mark when the revs worked there way down until it stalled.tried starting it & no go,did the spark plug test using another plug & had a good spark but then noticed that the fuel filter was nearly empty.

let it sit for 5 mins & the filter filled back up & the mower started again straight away.did the same thing again after another 30 mins mowing. i have noticed that the fuel cap doesn`t tighten when you screw it on & leaks a bit of fuel,could this be causing air in the line ?

cheers
jason

Jason, please do the test I asked for on fuel flow through the fuel line. Disconnect the line at the carburetor, and let the fuel run into a cup. See whether it continues to run at full flow, or can only sustain a trickle. Continue the test for at least a cupfull of fuel, preferably more.

I am trying to check two things here, either of which could cause your problem. The more likely of the two: the vent in your fuel tank cap may be clogged:



Cleaning that vent should be a routine service check.

The second thing the flow check will test for, is an obstructed fuel filter or one that has been installed backward.

The reason the clogged tank cap is the more likely problem, is that it takes half an hour's running for the engine to stop. Given that you said the tank is about 3/4 full, it would take a while to create a decent vacuum in that amount of air space.

hi grumpy,i did the fuel flow test & it took about 3 mins to fill the cup but this is with the fuel line pointing down.from the tank the fuel line runs down to the tap then down to the filter & wraps under the head & then up to the carby.the filter is on the right way, i have checked this but will be replacing it with a new one.

in regards to the fuel cap, i don`t think it`s the correct one for the tank.it doesn`t fit properly,has no vent but someone has put a hole through it previously,it has BP embossed on the top of it.