Wheel Horse Starting…Choke

[vhgmcbuddy]

Hi All
Recently purchased Wheel Horse 800, starts fine without choke, and if left to arm up for a few minutes runs fine. If you apply any choke, or try to increase revs before fully warm however the engine will not start or dies……over choking?

I read in the engine manual I found on the www that a choke plate modification, open out the holes in the choke plate, is recommended. I have not stripped carb yet as engine runs fine, but something tells me all is not as it should be with this situation and starting problems are around the corner if I do not sort this out…..

All comments welcome

Cheers

[wristpin]

Assuming that it has a Kohler engine, before modifying anything check that the valves and valve seats are in good condition. Remove the valves to inspect them and if necessary get them re-faced and the seats skimmed. Otherwise just lap them in and carefully set the clearances.
I had one kohler that led me a merry dace, dying when the throttle was opened – cured by closing the points a couple of thou from the recommended setting. That tip courtesy of Paul at Meetens many years ago.

[stuart]

I have a parts list for a 1974 “A.800 RANGER” model and it has a vertical crank 8hp Lauson engine fitted.The carburettor will have an adjustable needle valve (main jet) and an adjustable idle mixture screw which would need setting up.I would suggest one and a half turns each as a starting point.Due to the age of the engine,general wear and tear and how well its been serviced etc will have a huge effect on its running and reliability !!.
If the engine dies when the throttle is opened this would suggest a lean mixture.
Also make certain the contact breakers and condensor are in good condition and correctly set.

[vhgmcbuddy]

Thanks both. Will check these things, especially points. The engine after a few mintutes running is tip top, runs ticks over and responds well to the throttle, nice and tight, governor works well to regulate varying loads.

Also seems quite economical, as used only half a tank of fuel for a days logging pulling loaded trailer up a long and in places steep hill. engine breaking also quite good on decent.

Just this niggle that no choke is needed, which is a bit odd. I will look at the points, and if we have any trouble with it will lap valves this winter. Thanks again.

[hitchinsm]

Number of points; do not get yourself fixated on modifying the choke plate. If it was a generator or pump with a throttle and choke combined I would think about it, but as it is a Wheel horse with a manual choke do not bother. In all honesty quite a lot of them fire right up on tick over without any choke at all.
Remember the old ad-age; the majority of fuel problems are electrical. Make sure the points and condenser are ok and the ignition timing is correct. You have already received some good advice on the valves. Before you start taking the engine to bits too much, re-set the valve clearances. Too often valve clearances are ignored, the valves hammer in and have no clearance, make absolutely certain that the engine is on TDC when you set them (Top Dead Centre)
If you have access to a cylinder leakage tester this will allow you to hear if any air is passing the valve seats, a tiny bit is normal.
I am assuming this is a K or M series engine, that being the case it will have a Kohler or WALBRO carburettor fitted which are all copies if the original Carter carb. The WALBRO is different in many ways due to the emission controls incorporated into it, that being said the best way to describe these carbs is simple and crude. The main issue is that they do not have an accelerator pump which would shoot a small amount of fuel into the engine intake when you open the throttle stopping the hesitation which is caused by the sudden opening of the throttle making the mixture go lean. Anyone who has owned a Ford Cortina or Capri circa 1968 to 1975 will know all about this, in reality it over fuels the engine for second, creating emissions that are not wanted.
The last but important thing to remember is that K and M series do not like the mixture lean or having the ignition advanced. Depending on which cylinder head you have a nice hole about ¾ inch diameter will burn through the top of the piston.

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