A Hayter Spirit arrived this morning; it starts and dies almost immediately. I suspect the fuel input is blocked as it primes okay and then does nothing more. The rear roller auto drive is also faulty. The guy says he's owned it for 12 years and it's never been serviced 

I think the gasket between the carburettor and the fuel tank is flimsy and known for causing issues.


I am finishing a Stihl 545 and will get onto the Hayter later today.


Does anyone have experience of these?

It was shocking and needed a cleanup. It starts the first pull but runs rough. It needs a new air filter. Are these machines known to be fussy regarding the air filter? It certainly doesn't like it without the air filter.

Quote from: Changy on June 06, 2023, 10:28:02 AMI think the gasket between the carburettor and the fuel tank is flimsy and known for causing issues.

The older Spirits with the Sprint engine on them do require a new diaphragm and a carb clean occasionally.  Diaphragm and gasket part number is 795083 very easy to fit. Just try to get the old gasket off in one piece when you strip it, just in case your plastic carb is distorted which can be remedied by doubling up the gasket.

Also make sure plastic intake tube isn't cracked or loose and make sure the o-ring is located into the carb. 
 

Quote from: Mick on June 06, 2023, 05:36:26 PM

Quote from: Changy on June 06, 2023, 10:28:02 AMI think the gasket between the carburettor and the fuel tank is flimsy and known for causing issues.

The older Spirits with the Sprint engine on them do require a new diaphragm and a carb clean occasionally.  Diaphragm and gasket part number is 795083 very easy to fit. Just try to get the old gasket off in one piece when you strip it, just in case your plastic carb is distorted which can be remedied by doubling up the gasket.

Also make sure plastic intake tube isn't cracked or loose and make sure the o-ring is located into the carb. 
 

Cheers, Mick.

Is the intake tube removable, and is it a case of trying to clean both of the filters?

The gasket has bubbled and looks dodgy. I looked at the new part and it's in two pieces; it is self-explanatory when fitting them.

Who is the best supplier to order from?

TIA

Changy

The intake tube is bolted on to the top of the engine block with two screws on the exhaust side, so you can only check those with the engine cowling off.

As for supplier, you should be able to get one of those diaphragm and gasket kits locally from your nearest mower shop, or virtually anywhere online such as,

https://www.lsengineers.co.uk/diaphragm-carburetor-briggs-and-stratton-795083.html 

Quote from: Mick on June 07, 2023, 03:21:53 AMThe intake tube is bolted on to the top of the engine block with two screws on the exhaust side, so you can only check those with the engine cowling off.

As for supplier, you should be able to get one of those diaphragm and gasket kits locally from your nearest mower shop, or virtually anywhere online such as,

https://www.lsengineers.co.uk/diaphragm-carburetor-briggs-and-stratton-795083.html 

I've replaced the gasket and diaphragm and cleaned the carburettor. I checked the fuel tank and carburettor for distortion, but both are straight and true.

The mower starts on the first pull and runs well for about two minutes. Sadly, it then almost stalls, there is a small puff of smoke from the exhaust and then it runs well again.

Any ideas are welcome. 

I can't find any issues with the carburettor or the air intake. It has a new air filter and spark plug.

I rechecked it, and it ran fine for a minute. The video is from a minute onwards. What is happening, folks?

https://youtube.com/shorts/L2RpTN6OCE0?feature=share

Quote from: Changy on June 07, 2023, 12:18:35 PMThe mower starts on the first pull and runs well for about two minutes. Sadly, it then almost stalls, there is a small puff of smoke from the exhaust and then it runs well again. 

Years ago on mowers that had the choke lever, if you messed about moving the lever up and down while it was running it would almost stall and you would get the puff smoke like you describe.

Perhaps if yours is the same as the one in this video, you could compare the choke action:


This video may be useful:

The guy had also changed the gasket but still had problems, around 10:25 in to the video he says the problem was caused by the seal rings on the carb, there are 2, 1 black, 1 white.

Quote from: Rach on June 07, 2023, 03:22:57 PMThe guy had also changed the gasket but still had problems, around 10:25 in to the video he says the problem was caused by the seal rings on the carb, there are 2, 1 black, 1 white.

No there's only one o-ring the white one is the snap in retainer for it. It holds the o-ring in the carb.

Hi @Rach and @Mick

There is no choke on this carburettor; I had a Hayter Harrier and became familiar with that type of carb. The black o-ring is in good condition and held in by the white snap ring. I will remove the cover in the morning and check the air intake tube for damage.

If you can think of anything else to check, please let me know, as it is driving me up the wall!

Quote from: Changy on June 07, 2023, 08:45:36 PMHi @Rach and @Mick 

If you can think of anything else to check, please let me know, as it is driving me up the wall!

Does the engine mess around or cough and splutter when you move the machine around?  If it does then just add the old gasket on top of the new one and see if that cures it.

Quote from: Mick on June 07, 2023, 10:19:30 PM

Quote from: Changy on June 07, 2023, 08:45:36 PMHi @Rach and @Mick 

If you can think of anything else to check, please let me know, as it is driving me up the wall!

Does the engine mess around or cough and splutter when you move the machine around?  If it does then just add the old gasket on top of the new one and see if that cures it.

I haven't noticed it playing up when moving it around, but I will test it this morning.

The annoying thing for me is the top cover; it's secured with a 1/4" bolt and is the one size I didn't have. I bought a single socket and must ensure I don't lose it! I have 4.5mm 5.5mm and 6mm, but no 6.5mm. 

FIXED IT!

The mower now runs well, with no coughing and spluttering. I checked the gasket and was concerned I could see petrol; I think it was paranoia. I had my 1/4" socket from a local car spares shop and was ready to remove the cover. Ironically, I ordered a socket from Amazon and some other kit, but a Muppet packed it and didn't seal the carton. The socket fell out en route, as I discovered to my chagrin last night! 

The bolts on the intake tube were not tight. As you say, Mick, you don't need to hang on them, but at least pinch them up snugly. I tightened them, took Mick's advice, and fitted the old carburettor gasket. Yes, a belt and braces approach, but I prefer it that way.

I primed it, grabbed the starter rope, and it fired up on the first pull. I left it running for a few minutes, and it purred away.

I don't know if the problem was the loose bolts, gasket or a combination of the two, but I don't mind because the guy will be happy with his mower.

Happy days!

Thanks to all for the help; much appreciated.

Quote from: Changy on June 08, 2023, 12:46:58 PMprimed it, grabbed the starter rope, and it fired up on the first pull. I left it running for a few minutes, and it purred away.

I don't know if the problem was the loose bolts, gasket or a combination of the two, but I don't mind because the guy will be happy with his mower.

Might have been a bit of both, but the doubling of the gasket cures a lot of these issues, the carb being plastic and mounting surface of the carb distorts and causes leaks etc.  That's why I try to save the old gasket intact just in case I have to do this. It's not a official recommended way to fix them, but it saves replacing the carb.

Glad it's fixed though.