spudulike

I got a kit with a pressure gauge and cylinder to do mine a few years ago in an old Renault Scenic....it worked fine. I would assume the smell was like what a schoolboy would call an "eggy fart"

Got to agree, I reckon the 7 pin will rob the saw of torque on a 14" bar but may be faster on a 12" bar. If you don't use the full bar length in the cut then it may work but my thinking is most climbers want a fast, non bogging precision cut and I would normally stick with a 6 pin.

Yup, the carb is a Zama ZO11 and happens to have "RB51" on it and Zama use "RB" to denote a carb kit hence the confusion. The metering diaphragm looks like the early C1Q ones used on the Stihl 020T and others, that is a common part as will be all the metering parts as many of the Zama and Walbro carbs use the same parts - no need to reinvent the wheel on each type of carb! Looks like Ratman beat me to it.

80psi is good for the first pull, 120 isn't great but as long as that 80 is correct, your compression shouldn't be the issue as the machine fires on the first pull and this model never makes top compression figures. Will be interesting to see how the new coil goes.

One of the most used Zama carbs are the C1Q type

As Mr Rat said, many Zama carbs use the same parts. Looks like a Zama RB kit would work for you.

Not being funny but I have never read the manual and have rebuilt a few hundred of these machines. I only read the manual when I am well and truly stumped and it rarely happens nowerdays....the joys of being an old fart!!

The metering arm springs tend to compress causing the needle valve to leak. Try changing the needle and spring.

And me, keep us posted.

So the heat is definitely the issue.....just depends if it is killing compression or spark You could close up the plug gap as a test, try 0.25mm, it will make it easier to get a spark. Not a solution but may help to determine if it is the coil or top end. Looks like a hot compression test and regapping the coil and plug may give you the info to fix it

The hot compression will be interesting, 130 on one pull when cold is very good but if a saw runs and revs well when cold then not start when hot, it may be the coil. Try closing up the gap a little, I have seen old flywheels lose their magnetism before. Have you checked the fuel tank breather? This can give running issues, bogging and lack of power after a bit of running. The simple way is to drain the fuel tank, pull the fuel pipe off the carb and use a Mityvac on the fuel tank on vac setting to see if the breather is allowing in air.

Also check the compression is good when hot. Does the saw start OK if left for an hour?

Sounds like the condensate from the Aircon isn't draining correctly...check the outlets the water comes out of.

130 on the first pull is damn good, 70-100 is much more common so that is all fine. I would try to use a piece of printer paper to set the coil to flywheel gap. I had a 460 once that was exactly like yours and just had a larger coil to flywheel gap than was normal. This is worth a look at. Other than that, has the carb low screw been set correctly? Around 1.25 turns out should ensure it is workable...as long as the limit cap isn't on, if it is, just wind it out fully. I always check everything and if it all fails, it has to be the coil. Throwing £70 at a coil at the first stage isn't in my work ethic. BTW, aftermarket coils are pretty crap at best - best get an OEM one and second hand if possible.

The gasket often has an overhang like your pics show, the screws can come loose, I had a massive air leak once on an old 480CD like that. You can see if the screws are loose and if not, loosen them to see if you can push the gasket back up and clamp it again...worth trying before doing a permanent repair. You will see a section of gasket appear from the case join under the muffler if it is pushed upwards from the tank or it may just scrunch up😖

It looks like it. If time is not an issue, there may be some milage in loosening up the case screws, and seeing if you can push the gasket up a little and then clamp it up again. I have done this on the earlier 560xp and managed to fix a leak for not too much£££ It may work but if ADW is doing it for two hours labour, rip his arm off....I am thinking about subbing my Husqvarna work out to him😉

I guess I must just be a slow worker, cleaning the saw and removing all the covers, muffler, cylinder, carb, air filter, bottom plate under the carb, clutch and drum, flywheel, splitting the engine from the fuel tank, splitting the engine, cleaning the old gasket from both halves of the casing, possible the crank may pull a bearing out.....reassembly, pressure and vacuum check, more reassembly, run up and tach tune if normal carb or test in wood if AT....a for two hours, circa £100...bargain in my eyes. Most dealers wouldn't bother. Years ago I sent a local guy to the local big dealership to get his engine split and I didn't have splitters back then. I had the impression they would have the correct kit.....he came back and said the screws came out and the big copper mallet was used on the crankshaft😱and ...it was the first engine he had split....it sort of realigns your thoughts!

You may find the screws have just come loose so try tightening them up or take the cap off and shine a torch in to the tank and see if the gasket has dropped in to the tank cavity. If the gasket has been pulled in, it will probably need splitting and a new gasket to be fitted. 2 hrs seems a good quote from ADW, get him to do it!

That is because I have a pride in my finished product. I don't do it because I like doing it!

Cleaning chainsaws, that would be a first for most!!!

The first thing I would do is check the compression cold then hot. You need at least 150 cold, more is good and around 130 hot is borderline. A visual through the exhaust port will tell you if you have a fried piston You can pull the saw over slowly and it should feel pretty punchy and springy as the engine is pulled over top dead center. If this is OK, try bending the end electrode off an old spark plug and then test the spark in subdued light and pull it over hard. You should be able to get a spark with this modified plug hot and cold. The carb gauze strainer may be partially blocked, take it out and look at it against a bright light using a magnifying glass. The carb l screw may be set lean, this can cause starting issues. Check the pump diaphragm small sealing flaps, these can get perforated by the holes underneath them. Check the metering diaphragm is still flexible and the metering arm is level with the sealing part of the carb body. These carbs have accelerator pumps and it is always worth fitting new on a service. Usual symptoms of a bad pump are uneven idle.

13500 is about right.

Linen absorbs more moisture than most fabrics making it one of the best for hot weather.

Dirty air filter, too much oil or running rich!

In my book it is pretty sad that this nest has been destroyed. I have never seen a Goshawk in the wild and with this sort of action, it is unlikely I will any time soon. £100.....really!!