Howard 700 rotavator fuel problems

[ian husker]

I bought this rotavator a couple of years ago and it hasn't been out of the garage since. The problem is, if I pour some fuel down the plug hole it will start and run for about 15 seconds, then backfire like mad and stop.I have had the carb. down and cleaned all the jets etc but it is still the same. I have just found out that if I start it and jab the tickler like crazy it will keep going,so it sounds as if the float level is too low.The carb is a Villiers B24.
I wonder if any of your learned experts would give me any advice on adjusting the float level.Any advice and comments would be most gratefully recieved. thanks, Ian

[landie57]

What engine is it? Villiers/JAP other? I may have a manual if I know which engine it is.

[ian husker]

\\\thanks for your reply. The engine is a Villiers 28B. I have themanual but it dos'nt tell you how to adjust the fuel level in the float chamber. I had a pm from Pockets and he agrees that it seems like a fuel stavation problem so I think it's a matter of adjusting the level by trial and error.I'll have a go this weekend and see what happens. Thanks again Ian.

[landie57]

Just a thought. If the engine runs by pushing the tickler down it would suggest the float is too high, not too low. Is the needle valve clear? Best of luck.

[ian husker]

Yes, the needle valve is clear and working OK. I don't really understand how the fuel gets from the bowl into the engine but I would have thought that by holding the float down it would allow more fuel in. I much appreciate your tips and will have a tinker with it this weekend. Ian

[landie57]

Ian, fuel is sucked up through the centre piece which the float sits around. It is fairly common for the nut at the bottom of the float chamber and bottom of float chamber to accumalte a deposit of very fine reddish coloured sand like material, this maybe causing a blockage.

[ian husker]

Thanks for the explanation, so I assume the fuel has to be higher than the bottom of the tube to allow it to be sucked up. I have dismantled the carb, cleaned it out and blown through all the jets with compressed air. I wonder if I could have an air leak somewhere stopping the fuel being sucked up properly
There is an airtight plug on top of the carb directly above the tube but the book says not to remove it without special equipment so I am loath to take it off. i didn't get a chance to play with it today but I will have a go tomorrow. Ian

[landie57]

Ian the fact it runs at all would suggest to me that fuel is getting through, so I doubt you have an air leak. Another thought as it is a 2 stroke, I have a SIMAR Rototiller 35 (see VHGMC site from KG links page), which will not start unless I drain any fuel/oil residue from the bottom of the crankcase. It would be worth doing this just to elimate the possibility.

[ian husker]

Didn't get round to tinkering with the rotavator on Sunday as I got a new toy off E-bay( a vintage Allam generator set with a Norton 4 stroke engine) so I had to spend the day to see if it worked- it did eventually. However I managed to spend most of Tuesday in the garage and adjusted the float level a couple of times and eventually thought I had cracked it. The engine started and ran for about 30 seconds but then cut out- without all the spitting back and backfiring through the carburettor that I had before.
From then on it wouldn't start and I eventually found I had no spark to the plug . Checked the plug, plug lead, points etc but all seems ok which leaves the condenser and the ht coil. I'm wondering if maybe the fuel problem was a red herring and it could be an ignition problem- or maybe I now have two problems. The plot thickens. Ian

[Hortiman]

Hi Ian
I hope you are sorting out the 700, they are notorious for this spitting back problem.
I have found that there is usually a minute air leak on the joint between carb and manifold, may be worth truing up the mating surfaces and using a new gasket.
sometimes excessive wear around the butterfly can cause the problem.
I will not disagree with anything landie57 says !!!!
P.S I have some new floats for that carb if you need one.
For magneto spares try John Cruse, The Mower Centre,
Hailsham, East Sussex. He has shed loads of old Villiers stuff. 01323 842477.
Regards
hortiman

[ian husker]

Hi Hortiman, thanks for all your advice and tips. i haven't had another go at the 700 yet apart from spinning it over without the plug in just to make sure there was still no spark. I'll have to have a search on the net to find out how the magneto works before I start stripping it down. I'm hoping it is something simple like a wire earthing out as I had a really good spark before it stopped working. Hopefully I will be able to have a look at it this weekend and see what I can find. regards, Ian

[landie57]

First suspects in the 'mystery of the missing sparks' are points and HT pick up which can suffer from oxidation. But as you have had a spark recently and also noting the comments from hortiman, it may be the condensor. I had a similar problem on my Trusty (two wheeler), I stopped the engine and found no spark on trying to restart, the condensor had failed. I used the spare I carry in my Land Rover as a temporary fix.
Looking in the spare parts book for the Villiers 28B, it has a fairly standard Villiers type flywheel magneto. If you have not had one of these apart before it is worth noting the comments in the book regarding flywheel removal and replacement, (yes you will need to use a hammer). Best of luck.

[ian husker]

I eventually got round to stripping down the ignition system.couldn't find any thing wrong so cleaned everything and put it back and I now have a spark again.I remade all the inlet gasket joints using silicone liquid gasket. Then engine now runs after a fashion with a few backfires and some clouds of white smoke when I move the throttle lever. There seems to be a bit of play on the butterfly spindle and I'm wondering if it's getting air in and upsetting the mixture.I wonder if anyone knows of a way to take up this play. I had thought of trying plastic metal. The other thing is the governor doesn't seem to work and it runs flat out unless I slow it down on the throttle lever. The governor holds the throttle wide open when the engine is stopped and doesn't move when it is going, which doesn't seem right to me. Finally-anyone know of a way to glue the little felt pad onto the arm on the contact breaker. I've tried normal clear glue and superglue but neither seem to work. Cheers, Ian

[Hortiman]

Hi again Ian.
Sorry not much time to reply at present, but you must remember that the throttle control acts as a decellerator on this machine not a accelerator as is normal.
Regards
Hortiman

[Parman]

Hi all
A very old thread I know but if anyone can help I am trying to set up my Howard 700.
It starts very well first pull but It runs very fast (screaming) on open or closed throttle and I can't seem to slow it down, it also lacks power and I have to work the clutch to keep it rotavating.
Any advice very welcome
Thanks
James