GardenKit

In the cold light of day I need to correct my quoted post, before someone else does:blushing: The practice is right, the terminology wrong. The pilot jets are of course easily unscrewed from the bottom of the float chamber. The things under the brass plugs are the pilot circuit mixture screws. They do still need to be removed for a good cleaning. The things I often refer to as mixing tubes, are in fact the main fuel nozzle.

Hahaha, thats 'sods law' breezeblock. It usually happens t'other way for me. Its OK when I service it but plays up when it get backs to the owner:laugh1:

Very well described Wisecobandit, and this is indeed the way to clean a small Honda carb that hunts on idle, but wont cure one that will only run on choke. That will be a main jet blockage.The Honda carb cleaning picks ( thin wires) help to shift stubborn solids from the pilot jet, or a good boil up in the US cleaner helps. Even then they dont always work and a new carb is required. The carb in question on this thread was from a GX390, but a new carb has been ordered for that. The carb now current belongs to Colletti and is from a GX670 twin cylinder. These are much more complex carbs with twin throats, one for each cylinder. They require more carefull cleaning. The pilot jets are sealed in the top cover under brass plugs which need to be drilled out to get access to the head of the jet so that they can be renoved for cleaning. All other jets are easy to see and remove, but dont try to remove the two mixing tubes with the little rubber caps, or try to remove the caps, unless you have replacements.

Ahh, I lived at Haydon till I was 10. Grove Wood Road. Spent most of my childhood stealing coal from the batch:laugh1:

They are getting more common Jon Whereabouts? Peasedown?

Well done Jamie for posting this. There are one or two serial offenders who delight in putting others down by picking fault with everything. The problem is that when I feel 'attacked', I tend to fight back, making me no better than them. We all need a little reminder from time to time, so maybe this thread will encourage us to treat others with just a little more respect.

This is weird, as I agree with everything you say in this post Mr Treequip:thumbup1:

Hahah...The Three Thicketeers

You too??

I do understand the process of HAVS monitoring, but as yet it is not something that is done in the chainsaw service shop, so as a narrow minded mechanic it is something I leave to designers and testers. What is done, or rather, what I do, is to check each AV individually to determine their serviceability and, if in my judgement they need replacing. Apart from replacing them as a matter of course, that is all I can do. The decision to replace as a matter of course, or as required, is the subject of this thread. If we were to have to carry out HAVS tests on a service, then we would indeed have to interpret the results. The test would show vibration levels which would be compared to the levels of a new saw. We would then have to identify what was causing the excess vibration. This would involve checking the AV's individually as well as other factors. I have to admit to being a little wiser now as to why some customers may feel they need the AV's replaced in order to satisfy their HSE policy. This is something I had not previously considered. Thank you to all contibutors to this thread for that. And I do sympathise with you over your shot hands, Treequip. Hopefully the strides forward in AV technology and HSE directives will save the younger generation from similar problems.

I think you have misunderstood what I said. I have been referring to testing AV mounts. Thats the little bit of rubber and metal, or a spring. Can you find me some kit to test those individually?. I doubt it. Sure, there is kit somewhere to test overall vibration levels of the kit, but this will beyond normal dealer facilities and will require expert use to interpret the results. An increase in vibration could be due to many other factors than an AV in need of replacement. I do agree that in general rubber hardens with age as it 'dries' out, losing the ingredients that keep it supple. And springs lose their temper. But any saw user has seen some of his AV's go soft due to fuel and oil contamination. So in respect of my opening post on this thread, I take it that you are in favour of changing your AV,s on every service?

Thats the regulator/rectifier thing i mentioned earlier. it converts the AC current from the alternator in the flywheel to DC and regulates the output. You can test the output from the alternator on the wire that plugs into the regulator. If no output from alternator then take off the flywheel to check the magnets and windings. If there is output from the alternator , but not from the regulator then replace the regulator.

Just one of todays jobs. The moral of the story is do not put your Kawasaki brushcutter down on a loose gravel path.

Your dealer is about right. The Honda carb is very fussy and hates dirty or stale fuel. The 'hunting' is typical of blocked jets in the carb. Most of the time a good US clean does the job, but every now and then I have to resort to a new carb. When cleaning the carb it essential to remove the main jet and the venturi jet pipe. These will need cleaning and possible 'pricking' of the holes with the appropriate size cleaning pics. There are perfectly good 'after market' carbs available for many honda engines.

The alternator is situated inside the flywheel. This generates the current which is fed to the battery via the rectifier/regulator which is situated externaly on the low left as viewed facing the flywheel. These engines do have a habit of losing the alternator magnets which come unbonded from the inside of the flywheel.

Glad we were all able to help, and pleased that you have it sorted. And, as said before, glad you posted your result.

Some very valid points there. In the absence of any test gear for AV, (which does not exist as far as I know) then the only way to check is to 'to look, and twist'. This would be the norm in the industry and to an experienced technician will show up weakness. Of course, in this way we cannot tell if a few percent of Anti Vibe has been lost or indeed gained. (does a 'soft' rubber, or spring, absorb more vibe than a firm one?) So the only way to revert to factory levels is to restore to factory levels, so I guess its down to the person paying the bills. If he wants new AV's he can have them. I reckon most users will be content with just knowing they are in good condition, and probably be a bit annoyed if changing them on every service were the norm. And anyway it would depend on service intervals too.

Very true, especially on large tanks with a large surface area, and especially on metal tanks. Really quite unusual to find any water in small plastic tanks, I would guess only around 5% of the machines i service have any water present.

Its gone quiet on here, I hope I have not offended anyone, especially Steve with that comment, it was only a joke, promise:blushing:

Glad its not just me. This guy works for a government funded body and says that they have to be changed on service because of the employers requirement to abide by vibration levels. Apparently this other dealer always changes them 'just in case' . I found this strange, and very possible akin to a 'rip off'

Ar**hole:biggrin:

There has been a winner, Yes its Rich 2484, He had his prize earlier, with help on a Honda problem.

No no no! And I thought I was getting somewhere with A..........

I had a new customer in the shop this afternoon. He asked about chainsaw servicing, and asked if I changed the AV's on every service, as apparently his current dealer does. I think this is a bit over the top, I check them of course, and change if required. Do any of you have your AV,s changed on routine servicing?

Noooo..