OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Victa Walk-Behind Rotary Mowers Victa stopped dead - feels electrical

Hi, I'm new to this forum and find some very interesting reading.
However, I have a problem with my Victa, which I think is a Utility Pro.
I had it many years and it has been reliable for the light work it gets every so often. A couple of weeks ago it stopped dead just as I finished my cutting.

I suspected an electrical failure so I took the cowl and flywheel off for inspection. The points looked a bit dull, so I gave them a light clean with fine emery paper. I put my multi-meter across the coil and got only 0.8 ohm. I would have thought it should be much higher resistance but I have nothing to go on.

So my questions are before buying new parts are:
Has the coil failed and needs replacing?
Should I install the electronic an ignition kit to replace the old points while I'm at it?
Should I refurbish or replace the decompressor as well?

I think it is a Series 70 MKIV engine, with G4 Carburettor.
Engine number 19 720 453 2

Thanks for any advice.
Would include a photo if I could figure out how to do it.

Here it is. [img]https://www.outdoorking-forum.com.au/forum/uploads/usergals/2015/02/full-8911-20469-victa_comp.jpg[/img]

OK first hi and to ODK.
You'll find it quite cool and educational here.
Second here I'll put your picture up here:

Yes it is a Victa Pro I have one just like it.Although I think yours is in better condition than mine.
To tell you the truth I've never actually looked at testing coils with a multi-meter.I guess I've never been taught how to or what I'm looking at.Maybe somebody will show me how one day.I'd like that.
So I'll tell you how I do it (Not the most actuate I know),but it still lets me know.
Pull the spark plug out and attach the lead and pull the starter and just watch what colour the spark is.If it's a yellow colour then there is a weaker spark.If it's a nice blue colour then there shouldn't be a problem at all.
As far as changing to electronic ignition I think that comes down to personal choice.I think it was about 12 months ago there was someone else tossing up about this idea.I think for memory he changed his mind,but he was looking at some aftermarket brand new set up and it wasn't worth the cost.I guess if you got a setup of another mower you could.I just think it would be a lot of mucking around for little improvement,but that's just me.
With the decompressor it should be the serviceable type unless it's been changed.It wouldn't hurt to have a look at it and maybe changes the foam pad in the bottom as they usually fall apart.
From your engine number comparing it to my own personal records I keep(so from my own observation)it is a original engine for that model from 1972.
I am curious now if anybody has some information on this model,like a spare parts listing as my one is from 1978.That seems like a very long run for this model.
I hope this has been of some help.

Here is a rough guide to checking a coil with a multimeter. Disconnect the kill wire and read the resistance between that and the core. It should be low in the order of single digit ohms. My Kubota one factory spec is actually 0.6 ohms. Then check the HT output to the core. It should be in the tens of kohms range. Again the Kubota factory spec is 12.5kohms (within 20%). I found it wiser to remove the HT lead and check it straight at the terminal as well as at the end of the lead then you will know if it is the coil or the wire if it reads open circuit, like mine did and it turned out to be the cable, thankfully.

Blumbly, Thanks for fixing the picture.
So it's a 1972 model.
I've had it a long time and it doesn't get much work, and I can't remember where I got it from.
I will check the spark.

OK. I just took the plug out and checked the spark expecting there to be none.
However, there was quite a good spark, I wouldn't say bright blue, but bluish yellow as far as I could see. So I put it back in and it started! After trying for a couple of weeks without a kick!
It's sounding a bit rough, so it might be an intermittent fault Perhaps the condenser is faulty. I will try it again in a few hours.

I've decided to pull it down and re-paint the cowl, base and handles.
I live near the coast and it gets condensation on the top surfaces in the winter, even though it is stored in a shed.

Check the cutout switch rubber boot in the carby.
With these G4's, the rubber perishes in time, and lets the contacts stay in 'made' position, cutting out the spark.

Good rundown on this issue HERE

The ODK Online Shop has decompressor refurb kits available. If yours is the rebuildable type, it will have 3 clips holding the lid to the body.

Thanks aussietrev I'll give that a go.I might sit down with ignitions this afternoon and see how I go.
Styx you don't think there could be dirt in the carby somewhere maybe even a dirty air filter.
Also check the fuel caps little hole and just make sure it is still open,just something that nobody checks but I've seen a few times.When that hole isn't open the fuel system can't get the fuel through.
Could even be the spark plug fouling up.

Thanks Gadge

That rundown on the cutout switch is quite complex and I will give it more attention.

The only things I have done since the engine stopped and wouldn't start are:
1. lightly clean the points with emery paper, but it wouldn't start after that
2. cleaned up the engine with degreaser and water. This may have affected the cutout switch.

So I'm not at all certain why it stopped and why it started later.

Thanks again Blumbly for your suggestions.

Seems I have a few things to check and do:

remove the carby and inspect & clean
check the cutout switch at the carby
check and maybe replace the air filter
check the petrol cap
re-check the points and clean or replace
check the coil resistances
perhaps check and refurbish the decompresser

Decided to restore the mower, so stripped it down and bought a few new parts.
Getting the baseplate colour match was a problem as no exact colour could be found. International Orange is close but mixing a colour by eye was better.







Now it is assembled I hope it will start.

Styx

nice job man

Can't get it started now.

Here is what I have done:

New float needle in carby
Added 2 brass washers to carby in an attempt to provide idle adjustment
Dismantled and thoroughly cleaned carby
Cleaned points and checked gap, OK at 0.50mm,(have new set of points but not installed yet)
Checked de-compressor and it seems OK
New CJ8 spark plug with gap set to 0.635 mm
New air filter
New muffler and washer
New fuel pipe from tank to carby
New set of blades.

Have spark at plug, but haven't been able to get it to fire.
Throttle cable seems changed, maybe due to adding 2 washers in carby.
Maybe flooded, so will try again tomorrow.

Styx

Hi Styx, nice job on the rebuild mate, it looks good. I'm a big fan of all the Victa 18" utilities. They're a tough, robust little mower that will mow just about anything you put in front of them.
As far as you're non starting problem is concerned, have you checked the piston and rings? Pop the muffler and have a look, they could be fried and not creating enough comp to start up.
When i have a non starting 2 stroke i do a couple of check in this order:
Check for spark, check for fuel, remove plug and check for flooding by pulling starter a few times, if no flooding is evident I spray a little aerostart to see if i can get it to fire. If it still wont fire i remove the decompressor and block hole with an old spark plug, if still no start remove muffler and blow through to see if it's blocked and do a visual inspection of the piston/rings.
Generally if i've gotten this far more often than not i've located the problem otherwise my last resort is to remove the head, inspect the head gasket to see if it's been fried in any particular spot and then replace it with a new one and try again. When changing any victa head or barrel gasket make sure to smear oil on it first prior to re-assembly.
Youve done most of these checks so do a visual of the rings and see how you go.

Thanks for your advice bigted.

When I dismantled the mower I had both the carby and muffler off, so I could see the piston and rings OK. They looked fine. So I don't think the problem is in the cylinder. As it was going just before I pulled it down, the problem is more likely the carby setup, as the spark seems OK.

I put two brass spacer washers into the G4 carby. This may have altered the mixture at idle, which is where the throttle lever is at cold start. I think I need to remove the carby and then remove the washers to take it back to original setting and see if I can get it to start.
Styx

So I pulled the carby down again and removed the 2 brass washers, re-assembled and managed to get it to fire but not start.
Pulled it down again and installed a new set of points, checked the O-rings on the manifold, checked the decompresser, seems OK, re-assembled, but this time it wouldn't fire.
So pulled it down again and cleaned the new points with fine emery paper, re-assembled and put hose from carby into larger hole on engine cover, nearer to the fan blades. Then it started! Seems to run OK, but haven't checked the idle adjustment, as pleased it was going again.
Cut-out switch seems to work OK.
Noticed that when you rock the blade plate back and forth by hand, you can feel/hear a slight play in the engine, which might be play in the gudgeon pin or play in the con-rod bearing on the crankshaft. Turning the blade plate you can find the spot when the play/knock is the greatest, then turn the plate 180 deg and the play is at a minimum.

So does this mean the main bearing or the gudgeon pin? How bad can it get before serious damage is done? What is it going to cost to replace bearings?

Styx

This morning I tried starting the mower again. After a couple of pulls of the starter cord it snapped back viciously, never done that before. Started but quite smokey, ran a short time then stopped. Now when I pull the cord it seems the decompressor is jammed shut. It is the type with the 3 small clips. I would have thought a "failure" in the decompressor would be a hole in the diaphragm and that would mean the valve remains open. Is somethinge else going on? Appreciate any advice here.

Styx

I have (on quite a few occasions) have had (and or seen) them close up completely.
Usually I've found it is due to some carbon build up inside down through the stem.Although I have also seen the top of the Valve bend and sometimes breaks which also locks it closed.I have found a lot of bent valves.Don't know how they bend but I have seen a few that do.

Thanks for the experience re decompressors Blumbly.
So I pulled it down again and removed the decompressor and found it open, and easy to close with a suck on the manifold tube.

Then thought it might be a timing problem, as I replaced the points a couple of days ago. So I set about removing the flywheel and found it very difficult, which is surprising as I had it off just a day ago. Eventually I got it off and examined it carefully for any burrs or damage to the key, shaft, flywheel hole, but found it in good condition, just a perfect fit. So I lightly greased the taper and put it back together, having found the points in position. There is no adjustable timing I can see as the points can only be adjusted for gap. Tightened it up and it started OK, idled OK. No kick back on the starter cord.

Cut grass very cleanly with the new blades. Can actually hear the blades slice through the grass.
So I'm none the wiser. Seems the engine is a bit temperamental. previously it has been reliable and consistent

Styx

Generally the reason the cord snaps back , and breaks your fingers , is a timing problem, it's firing at the wrong time. Something you've done in taking the flywheel off etc has put that right.
The points backing plate should be slotted at the mount screws, which gives you the adjustment.
Good to hear it's running again.

Not all points plates are slotted for adjustment, later ones are not, just fixed in position with adjustment to points gap available.