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Collection, Preservation and Display of Old Lawn Mowers

Suffolk Punch 17S Hunting

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Hi there, So a certain someone will sigh if they read this.... (Wristpin) LOL

My old mower was hunting, and after a 3 year battle I've sold it for spares.

I spotted a Suffolk Punch and thought "That will do me :)"

Spoke to the old Gentleman who seemed genuine, he started it first pull, off it went, he switched it off and job done. Paid the money and did the hour and a half journey journey home.

Got home, fired up the mower first pull, Brilliant!!! (Wait for it!!!!!)

Within about a minute it started hunting (NO!!!! NOT AGAIN!!!!!!!) moved the choke over and the Hunting started to subside.

You know what im going to ask now!! 

How the Hell do I fix this??? 

Once again Id be grateful for any help here. two mowers in a row :( 

Thanks 

Glen

Forums

hortimech Sat, 15/08/2020

The name 'Suffolk Punch' covers a multitude of machines and engines. A few good photo's will identify what you have now.

wristpin Sat, 15/08/2020

Perhaps the crafty seller had a bit of choke on?!

Otherwise all the usual stuff, clean the carb and check for inlet air leaks.

 

 

Glencmp Sun, 16/08/2020

Hi there, so this is the Mower. I didn't realise there were so many types.

I've not really any idea at the moment what engine or carb this is.

But as always im grateful for any help

Cheers

Glen

wristpin Sun, 16/08/2020

Looks like an AQ148 engine with a Dellorto carb. That carb is easy enough to clean unless muck has got into the fuel gallery that feeds the progression drilling’s in the Venturi. That is covered with a welch plug which usually has to to be renewed after cleaning. Also the main jet/ emulsion tube needs a certain type of screwdriver to remove it without causing collateral damage. Use an unsuitable screwdriver and the person who comes after you won’t thank you for chewing up the slot in the tube and damaging the threads in the carb body.

hortimech Sun, 16/08/2020

Bit of 'badge engineering' going on there ;-)

That machine was available under various names, Atco, Qualcast and Suffolk, slight differences, mainly cosmetic.

The engine is a Tecumseh and is no longer manufactured, but parts are still available.

All you can do is what Wristpin advised, strip and clean the carb, check for airleaks, check and clean the airfilter

the2ems Sun, 16/08/2020

I have the same engine, but different, although similar, carb. I'm just wondering, on mine, the little connection rod from the carb to the governor control is fitted different. Mine goes into the back of the governor arm, and into the carb from the top. I'm not an engineer, but I would have thought that going in from underneath, and then just having a small bend to stop it falling out might cause a little bit of friction so that it is not as free as it could be. 

Glencmp Mon, 17/08/2020

Ican have a look to see if there is any dirt etc, but if I dont have the correct tool to investigate the carb properly, I have noticed you can get replacement carbs on ebay for £12, is it worth it??

Henno Mon, 17/08/2020

Glen, don't replace it with some stuff from PRC. You can give a try yourself with spraying it with carb-cleaner in a few sessions. If that takes to long or you want a quicker result then bring the carb to someone with a ultrasonic tank. 

We, my neighbour and I, revived a completely seized Dellorto carb, like the one you have, with a untrasonic tank session and after that some sessions with car-cleaner. The engine runs now smoothly with Aspen.

Glencmp Tue, 18/08/2020

Thanks Henno, Ill hunt around to see if anyone has an ultrasonic cleaner.

I dont want to replace the carb as Id rather keep it original if I can

Ill keep hunting :)

Cheers

Glen

Glencmp Thu, 20/08/2020

Chris you are a total Gentleman :) was it you that offered ages ago with my old mower?

I was hunting to find the post but wouldn't find it, so ive splashed out and bought a small 3L US cleaner.

Im waiting for it to arrive and Ill get delved in this weekend :)

I totally appreciate your help, that was really kind :) 

Cheers

Glen

villiers98 Fri, 21/08/2020

The photo of the side of the carb facing towards the cutting cylinder APPEARS to show an adjusting screw rather than a plastic tamper proof cap. If this is so, and not a trick of the light then it should be easier to get it to run cleanly .Think it turns out to richen mixture. Only adjust after 15 minutes mowing so its good and hot . Never use old petrol ( > 8 weeks old)  -  consider Aspen fuel

To remove the main jet and air corrector above it you need a hollow ground screwdriver as wide as the jet exactly or as pointed out above it will destroy the jet slot and carb . Good quality screwdriver bits from a decent 1/4 drive socket set will work with care .

I d suggest an inline Honda type petrol tap so you can run it until the carb is empty each time

 

 

wristpin Fri, 21/08/2020

The photo of the side of the carb facing towards the cutting cylinder APPEARS to show an adjusting screw rather than a plastic tamper proof cap.

Specsavers moment! The welch plug is just to the left of the  adjusting screw, which in theory only affects the slow running mixture but if you are lucky,  it may find enough extra mixture to effect a cure.

When using the ultrasonic tank it’s good practice to alter the orientation of the carb’ during the session so that anything that has been loosened can “ fall out” of whatever drilling or passage that it was blocking. Otherwise it will just settle back to where it came from. Always good practice to have an aerosol of carb’ cleaner with a thin extension tube , to thoroughly flush out the remaining cleaning fluid.

wristpin Fri, 21/08/2020

The photo of the side of the carb facing towards the cutting cylinder APPEARS to show an adjusting screw rather than a plastic tamper proof cap.

Specsavers moment! The welch plug is just to the left of the  adjusting screw, which in theory only affects the slow running mixture but if you are lucky,  it may find enough extra mixture to effect a cure.

When using the ultrasonic tank it’s good practice to alter the orientation of the carb’ during the session so that anything that has been loosened can “ fall out” of whatever drilling or passage that it was blocking. Otherwise it will just settle back to where it came from. Always good practice to have an aerosol of carb’ cleaner with a thin extension tube , to thoroughly flush out the remaining cleaning fluid.

Chris G Fri, 21/08/2020

Hi Glen, good to hear you're sorted with a US cleaner, lots of little jobs they are useful for.

Try and get a cleaning solution which dries off fairly quickly not leaving any residue. Carb cleaner after a good session in the bath is a bit belt and braces but air lining the individual parts and galleries is good practice to dislodge any crap thats left.and getting everything super dry. Don't leave your fingers in the tannk too long when turning thngs around in the tank especially when its running. As above on the screw bit for the jet but don't get too paranoid, if the bit fits right and will not interfere with the (very) soft threads you will be ok. Probably more important is positioning yourself and the carb to do it - fixed vice with rubber soft jaws to clamp up and firm pressure with a good fit driver bit, as opposed to trying it in palm of hand :-)

For a non commercial owner of lots of 2 & 4 stroke stuff, I'm not sold on Aspen over draining tanks and float bowls and sticking that in the old car after a season, just my humble..

 

wristpin Sat, 22/08/2020

Carb cleaner may be “ belt and braces” but it will displace u/s fluid and debris and is more likely to be to hand in the average amateur workshop than a source of compressed air,  and is unlikely to to blow a needle seat across the shop, never to be seen again. No carb cleaner? then perhaps the dreaded WD40.

 

Glencmp Sat, 22/08/2020

Hey guys :) Excellent info on here, I'll digest it better when I re read it again tonight

So firstly good news without all your extra info...

Took the carb apart and noticed that it didnt look as if the bowl at the bottom had been put back in the right place?

Anyways, to carb apart but didnt remove any jets etc. Stuck in in petrol and set the machine off.

10m ins later took it out. cleaned it with carb cleaner and stuck it back in other way round, set it off for another 10 mins.

Took it out, another quick clean with Carb cleaner and put it all back together. put another fuel filter on and filled up with petrol

off it went, no hunting nothing, (You should have seen my face LOL) It looked like the bottom bowl was out by 180 degrees, put it back as per diagrams so that might have been the 90% fix.

But its still hunting but no where near as bad.... When I first started the mower it was a sweet as a nut, but after about 3 lengths of the garden, it coughed and laboured a little but when its under load and the blades are spinning you cant tell if its hunting, it seems perfect, its only when you take the load off, it starts hunting.

Ive popped a little video on youtube if anyone cares just to have a quick squint. - https://www.youtube.com/watch?v=rUEHQQ5p_Lc 

I have a funny feeling that the dirt may have moved, and then popped back intio place again??

Thanks once again guys, Oh I do have compressed air but I was a bit dubious to try it, but the carb seems so clean????

Chris G Mon, 24/08/2020

and is unlikely to to blow a needle seat across the shop, never to be seen again. 

True :-) a bit of common sense needs to be thrown in..

 

Glencmp Sat, 29/08/2020

So I have taken the carb off, removed the bowlat the bottom, and also unscrewed the Brass jet in the middle and blew everything out with the air line.

Popped it in Carb cleaner which made a difference, so cross fingers when I put it back together with the new seals Ive ordered it works :)

Only issue was the the tiny clip that holds the Float pinged off somewhere so I need that repalced as weill *sigh*  :)

Glencmp Thu, 10/09/2020

Ok, I need to pull in the big guns now :)

spares for this carb, what a nightmare. I've ordered 2 sets of Bowl seal and clip to hold the needle, and needle seal and nothing fits. Is there any company who can help with spares, or would you know of anyone with a working second hand carb for this mower? 
thanks again

Glen

 

Glencmp Fri, 11/09/2020

Thanks guys, Really appreciate that, I've sent off an email to check with them.

I picked up one of the ebay carbs for £10, It turns out the float is similar. so I've used the spring and float on the old carb. It started fine and ran fine, then the petrol started pouring out of the seal on the bowl, So Ill hang fire and see what Delorto say :)

Thanks again, Really appreciate it :)

wristpin Fri, 11/09/2020

I would guess , C**p between the needle and seat because if the needle was cutting off the fuel at the correct point the  fuel should not be as high as that seal which is to keep dirt out , not fuel in.

Glencmp Tue, 15/09/2020

Wristpin that is a really valid point!!!! I didnt think of that.

There doesnt seem to be any kind of seal where the needle would sit into, would you know if thats correct?? The Needle has a red plasticy end, and I cant seem to find a seal, I thought the red bit was the seal??

Mmm! btw, Delorto were excellent, heally helpful and I ordered the part yesterday 4pm, it was here today at 11am, cant say better than that!!

wristpin Tue, 15/09/2020

The soft tip needle seats into the hard alloy carb body - no replaceable seat. Try cleaning the seat with a Q-tip soaked in carb cleaner .

Glencmp Tue, 15/09/2020

Hey Wristpin, so put the new seal on, mower starts first pull!!! Over the moon!!!! Wait for it....

I see a drip of petrol, and now it's running out of the air filter!!

could it be that the Spring not long enough? I'll try the cotton bud but I'm thinking it's something to do with the spring length as it's pinched form a slightly different carb.

ill speak to Delorto tomorrow and see if I can get a float kit complete, and I'll give the needle seat a clean

 

wristpin Tue, 15/09/2020

I don’t think that the spring clip is the culprit. What is the complete model number of your Dellorto?  My experience of them is mainly those fitted to Flymo two- strokes and they don’t have a spring clip, the needle just hooks into a fork in the float.

With  the bowl removed, the carb inverted and the weight of the float resting on the needle, is it parallel  with bowl seat ?

 

Glencmp Wed, 16/09/2020

Your on the Money Writpin.

I spoke to Dellorto this morning and they said there is something not quite right about this set up.

Ive got bits from them today and Ill reset the carb back up a per their instruction

Fingers crossed :)

At least the mower starts first pull!! :) :) 

Glencmp Wed, 16/09/2020

Success!!!!!!!!!! :)

so the Old Bark who used to own the mower, had been tampering with the carb he put it back together wrong and had it running really really rich. The plug was black and there was a ton of soot.

so... spoke to Dellorto and they said there was something way wrong as there is no spring on the float. As it turns out it was the wrong needle and a spring. I got the correct needle, slotted it where it should be, filled it up with petrol and off it went first pull, but it started hunting again, I could have cried, but once I started to turn the choke off the hunting got less and less until it disappeared!!! 
But it was ticking over really quickly.

the governor spring was all bent but I thought I'll make do. The idle screw was fully screwed in and it's still racing, so I moved the spring basically to the very first setting which meant the mower at Tick over would cut out, the second hole in the governor arm was still to fast. I increased the idle screw until it idled properly.

i have no idea if that is correct but it worked fine.

so I need to change the air filter, change the oil and a quick polish and we are cooking by gas :)

thanks once again for all your help guys, it's been invaluable 

cheers

Glen

Glencmp Thu, 17/09/2020

Oh! PS

Does the Oil filter need coated on oil? or just dry? :)

hortimech Thu, 17/09/2020

I think you mean air filter, if so, yes it does. Clean it in water with detergent added, rinse clean and squeeze dry, leave overnight to fully dry, pour on approx 2tbsp SAE30 oil and squeeze to disperse it (do this over a drip tray to catch the excess oil), refit filter to machine.

Glencmp Thu, 17/09/2020

Thanks Hortimech, I did think so but as its a completely different mower I thought I should check.

I normally clean it out with WD40, ring it out and pop it back in?? Or should it be SAE 30? As long as its oil??

hortimech Thu, 17/09/2020

There is no way on this planet that WD40 can be described as oil, use the same oil as you put in the engine (which in most elderly lawnmower engines should be SAE30).

 

wristpin Fri, 18/09/2020

There is no way on this planet that WD40 can be described as oil, use the same oil as you put in the engine (which in most elderly lawnmower engines should be SAE30).

Yes, the best  thing about WD40 is their marketing!

Glencmp Fri, 18/09/2020

LOL Thanks Guys, I thought you might say that.

Oil Changed Filter in. But The Engine has a fierce amount of Carbon all over the head. This this has been running rich for a very long time.

Ill pop some Redex in it and just leave it alone, It runs, Idles, cuts fantastic.

Im happy now

Its only taken about 3 yers LOL

Chris G Sat, 19/09/2020

I thought Redex was an additive for keeping fuel injected systems clean?

Don't think any additive will reduce/abate carbon build up if it's been running rich.

If it's running ok now, be an idea to drain the carb and tank at the end of season, B&S Fuel Fit seems to work ok for stored fuel.

 

Henno Sat, 19/09/2020

Also for that horrible E10? FuelFit does not remove the ethanol does it? I prefer Aspen and yes it is bloody expensive but you almost can inhale the exhaust fumes...

hortimech Sat, 19/09/2020

Redex is older than fuel injection and it used to be sold as 'upper cylinder lubricant', it will probably break up the carbon, but would you want to do this in an alloy bore ?

The best idea would be to obtain an head gasket and then give the engine a manual decoke.

 

wristpin Sat, 19/09/2020

  I thought Redex was an additive for keeping fuel injected systems clean?

The original Redex  dates back to at least the1940s ****,if not earlier , when it was known as UCL or, as Hortimech says, Upper Cylinder Lubricant,   and the pump attendant would ask “ do you want shots”?  It was squirted into the fuel filler  from a dispenser at an old penny a shot.

It could also be used for an “instant decoke” which involved warming up the engine , setting it to a fast idle and dribbling Redex directly into the carb. This obscured the neighbourhood in smoke and made a nice smell - oh, and possibly did some good!  Those were in the days when older cars needed a proper decode every ten thousand miles .

With the advent of fuel injection they produced a version for injected engines , one for unleaded fuel and even a diesel additive.

When unleaded fuel was introduced, most of the small engine manufacturers recommend that their engines should be decoked before it was used. Also, as many of the older car engines had exhaust valve seats cut directly into “soft” cast iron heads it was recommended that the seats were machined out and hardened  inserts pressed in. Briggs and Stratton were ahead of the game and had been using hard inserts for many years. Villiers, not so!

EDIT   ****. 1922 !

 

 

 

Henno Mon, 21/09/2020

We could send wirstpin and hortimech to be a panel member on QI. Indeed quite interesting.

 

Glencmp Tue, 22/09/2020

Every day is a school Day :)

I think for this year Ill just add Redex and make sure the old girl is running correctly. Next year I may pop the head off and regrind the valves and change the head gasket. 

As this is running well im always a bit hesitant to go digging and do surgery :)

wristpin Tue, 22/09/2020

If it starts and runs, leave it alone - less stressful.

Going back to the Redex history; in the late 70s I helped my father clear out the garage of the house that they had moved to in 1934 and it yielded up one or two gems, a set of Egyptian number plates and bumper bar badges for the East African Motoring Club and Egyptian Automobile Association - all of which now adorn my workshop wall.

There was also a tin of white powder ( no, not that one) with a name like Powderiz that was applied after the Simoniz wax  polish of the day to help smooth it out and assist with the shine. Then there was a tin of foil wrapped cubes with a name ending in ....oids that were for reviving tired  batteries , one dropped into each cell, which in those days had individual screw caps. 

Another of Dad’s favourites was a Nenette duster. Still made today but in France ; just bought a new one . Thoroughly recommended for dusty dashboards and a quick flick round indoors.

Glencmp Thu, 27/05/2021

So just an update on this.

And to mention how grateful I am for all the help.

I'd sprayed Redex in the Sparkplug hole to leave over the winter. Fully drained etc.

Pulled this Mower out last week, filled it of petrol, Put choke on and pulled the cord, started first time (WOW!)

Epic :) Is not the word.

So i'll keep this old girl tip top and hopefully you might never hear from me again LOL

Should I tell you the hassle I've had with the new Hyundai Mower LOL

Thanks once again

Glen