I've purchased a Victa Mustang, MCA482, with a VEX60 Power Torque 2, 2-Stroke engine, and for the life of me I can't get it to run and I have no idea what's going on.
When I first received the mower, I started by changing the O-ring around the primer bulb plate, replaced the rubber grommets on the start/short leads, and gave the carby a good service and clean... No go.
I then checked the air filter, no problems there, all clean. I even tried starting it with the snorkel hose disconnected... No go.
I checked and cleaned the spark plug. It was a little dirty but cleaned up perfectly OK. I checked spark and it looked normal. I even tried a 2nd spark plug. The spark plug boot has been removed, so I wrapped electrical tape temporarily around the terminal... No go.
I checked the crankcase seal (Pull start side), and it was rather damaged and on very tightly. I changed that seal... No go.
I removed the head to check for any damage. A small part of the head gasket around a bolt wad damaged a little, but nothing significant. There was also a small amount of scoring on the exhaust side, but it didn't appear to be too bad. I reinstalled the head... No go.
I tested with another decompressor... No go.
I performed a compression test both with and without the decompressor. With the decompressor, it was lower obviously, and with a spark plug in the decompressor hole it was significantly higher and very difficult to try to turn the engine, so I know there's compression.
I noticed the spark plug was wet. I cleaned it off and spun the engine a few times to clear out excess fuel. I also rotated the poppet valve from position C to position A... No go, and the spark plug was wet again.
At one point, I tried starting it without the decompressor on, and the fuel tank off, and the engine fired once and shot a nice flame out of the decompressor port, so I know it can fire.
When trying to pull start, most of the time there's not even a hint it's going to start, and other than the above test with the decompressor off I've never seen/heard it fire.
Can anyone help? I'm completely stumped.
The only thing I can think of is if maybe it has something to do with the exhaust? Because the above tests should show that I have compression, spark, fuel (Too much possibly)...
Hi pau13z, welcome here and you have one of the best mowers ever built. The first thing I do once I have done all the tests you have done is fit a proper float needle, not those rubbish plastic ones on ebay, they just don't work. You need one of the brass/viton tip ones. I get 80/90% of mine running this way but there is always the odd one with compression that just won't fire up. These are the ones that even with a squirt of starter fluid down the plug hole and I can't get a peep out of them. These will not start, even after fitting one of my modified carbys on it. These I just put in my pile of non running Powertorques I might get back to them one day. Try the needle and if that doesn't work try the carby mod here, bit of work but guarantees to get them working. I do a number of these every week.
Hi NormK, thanks for the quick response. I just wanted to clarify a couple of things.
Originally Posted by NormK
The first thing I do once I have done all the tests you have done is fit a proper float needle
The float needle in there is the original one, and while I agree it may be an issue, if the mower is getting to a point where the plug has fuel all over it, would the issue be with the needle allowing fuel in? I would imagine if anything too much fuel is getting in?
Originally Posted by NormK
if that doesn't work try the carby mod here
I did a quick search for something you posted RE a carby mod but couldn't find anything, do you have a link?
I do have a new spare carby that I purchased for testing purposes, so I might try that. It'll also give me an opportunity to double check everything in the old carby.
I'll get back to you with the results. If it resolves it, then it's something in the carby. If it doesn't, then it shouldn't relate to the carby at that point.
While I'm looking into this, I'll take the exhaust off and take a look at that, and I might see if the mower starts up with the exhaust removed, just for testing. It might take a day or two, but I'll get back to you with my findings.
Regarding the exhaust, I have not found one that caused any issues, always the carby. One other thing to check is the main jet is clear. Before I went too far I would try a bit of starter fluid in the plug hole, sometimes it wakes them up. And don't be fooled by the plug being wet, I don't know why that happens sometimes and it won't start, but if I modify the carb they usually fire straight up and then you have full throttle control. Some days I might modify 3 carbs with probably a 90% success rate. The odd carb I just can't get to work for some reason, they just end up in the spares box
Hello Paul, You have done all the right checks......... But the three things you need are. Fuel Spark timing.......
Check for spark, I have found those two dicky wires that go into carb for power cutoff, sometimes touch and then you have no spark. good luck speedy Bundy
........................Keep your blades sharp......................
Hi Speedy, did you get your carb mod sorted? Sadly the theory of fuel,spark, and timing is not the total package to get these 2 strokes running. I have a pile of them that have all the ingredients but they will not give the slightest flutter attempt to start. A number of these I believe have been run on straight fuel, they have not locked up, turn over fine and have good compression. When time permits I will get to the bottom it.
Howdy and welcome pau 13z and a howdy to Norm and Speedie. I remember reading about the phenomenon of a spark being apparent with the plug out, but not being strong enough to sustain under compression. Is the spark a strong blue or a wierd colour that doesn't come on strong? Try swapping the ignition coil if all else has failed perhaps.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
Hi Norm, I took apart two PTs I was given last week. One had good bore piston but worn rings and shot base. The other was 30 years old...... rings seized in, but I got one out, it was good and used a Sabre Victa base that had a Briggs on it. I like to take the rings off to decoke them. and replaced front carby primer with another good one, new fuel lines.... I find all sorts of problems and missing parts, . I didn't do the mod on this one yet, but I have done a few and they worked OK... This one started after a few pulls. let it idle for a while , got low revs and higher revs......... I'll have to mow a lawn to see how it goes, but looks OK nice solid base good wheels.....
But you have to check you have a spark........ visible or do the feel the plug test........... I don't do that one....
cheer all specially pau 13z cheers speedy Bundy.... Our june rainfall is worst for 17 years......................................
........................Keep your blades sharp......................
Speedy, one other thing I have started doing with the carby mod is put a stop on the throttle control because I have had a couple of people force the lever too far backwards and this then pulls the ball inside the cam back and breaks the lower edge on the cam and then it has to be replaced
Norm, I had to do the opposite on a 160 FC on a Mayfair chassis. I extended the slot by 3mm so as the lever would engage the kill switch properly, as the adjustment screw at the front had reached its limit.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
MF, the reason that I have to stop the lever coming right back is because I don't use the kill switch setup, it causes too many problems. I put a 6mm bolt in there and this then allows it to stop with the lifter right on the highest points on the cam so that you can then use the idle adjuster screw to control the idle speed
I replaced the electrical tape with a spark plug boot as well.
After the carby replacement, the plug was still wet when trying to start, so again, I know fuel is getting through, and I know the fuel is good because I used it on another mower yesterday.
I tested the spark plug again after drying it off and the spark was there.
I have read some people report the spark colour can indicate a good/bad spark, however, I've read other posts indicating that's not the case. Also, not today but the other day, I did try with another plug and there was no difference.
I removed the muffler and OMG the fuel smell was horrible. I've never removed a muffler before but it seemed heavier than I would have assumed, though it seemed to be empty.
Trying to start the mower with the muffler removed I did get the occasional pop and exhaust gas, but the pops seemed very weak and it never seemed like it was going to catch.
I tried with the throttle in different positions... No go.
Looking through the exhaust port, you can see some scoring on the piston but as mentioned before, compression seemed normal so I'm not really worried about that.
Something I haven't tried is changing the poppet valve position, I left it in the recommended default for the replacement carby which was position A.
Finally and just a side note, the replacement carby came with a small rubber grommet for the cut-off wire that goes in the carby, but it didn't cover the entire plug and it looks like it was designed that way. This will prevent the tips of those rubber grommets breaking off inside because if they seal correctly, there's no need to have the rubber tip inside.. if that makes sense?
Anyway, any further advice or recommendations? I confess myself I'm almost at the point of replacing the ignition module, though I really don't want to disassemble the mower that much or incur the cost of replacing the ignition module.
You have spark so why replace the ignition module, the problem is the carby and fitting another one usually doesn't work either. This is all I can tell you, it is up to you to decide where to go from here, you want to get it running, modify the carby. Another test you must do is a squirt of starter fluid in the plug hole. If you do not get an attempt to start you are up against it, if it gives a flutter then the problem is carby. Wet plug indicates too much fuel getting in and that goes back to float needle
Ok, I'm leaning towards the piston scoring being the problem and nothing else. Turn off the fuel, remove the plug and pull the rope 20 times or so to clear out the excess fuel in the cylinder and crankcase. Replace the plug with a known working plug or a new one and try to start the mower ( still with the fuel off). If you get no love, give it a shot of starter fluid, and try to restart. If you get nothing and all that you tell us is correct then the engine is too far scored and not creating enough positive and negative crankcase pressure to start and most likely never will unless you rebuild it. If it does start then turn on the fuel and let it run to see what it does and you can further diagnose any carby issues, etc thereafter. There is no need to rebuild or modify the carby until you've seen if it shows any signs of life by using the above mentioned technique.
Exactly BT, if after clearing the crank of fuel, then using the starter fluid and if you don't get a hint of starting forget it. Problem is we have no history on this motor, is it a new found treasure possibly been run on straight petrol, or was it running 6 months ago and now won't start. One thing that does confuse me with them is the 20 motors I have sitting here that have compression but even then will not give a flutter with starter fluid. One day I will sort them out.
First, the jet installed in the replacement carby was the plain face jet. I swapped it for the ringed jet which is the one that's supposed to be installed.
So... I grabbed a new plug and tried it with the fuel off and then on... No go.
I removed the new plug and found it was wet so I pulled the pull-start mechanism at least 20 times (Exhausting!)... No go.
I tried with the fuel off at this point because I still saw what I thought was fuel coming out... No go.
I removed the fuel tank in case there may have been an issue with a leaky tap and the carburettor having an issue before moving forward further.
Removing the plug and finding it wet yet again, I tried the pull-start a few times with the plug out and noticed what appeared to be fuel coming out of the spark plug hole... even after that many tries with no fuel...
I removed the head and found a little fuel dripping down, and the cylinder appeared wet. I pulled the pull-start mechanism a few times and noticed what appeared to still be a lot of fuel coming out.
I removed the pull-start mechanism to check for fuel and on initial visual inspection found nothing.
I tipped the mower on its side and spun the engine a few times and quite a bit of fuel came out. I know it's supposed to lubricate the engine so I'm not sure exactly how much is supposed to be in there, but it seemed like more than there should be?
After emptying the fuel as much as I could and re-assembling the engine (Fuel supply still removed), I tried starting it with SYB. I got pops, and almost for a second it sounded like it was going to start veeeeerrry slowly... but it didn't.
I thought it could be because there was insufficient fuel, so I installed the fuel supply and tested again... No go.
I thought the scoring or compression may be an issue, so I tested again. With the decompressor on I got about 60 PSI and with the decompressor port blocked with the spark plug I got around 85-90 PSI (And trying to pull-start the mower was very difficult)
I removed the snorkel hose and sprayed some SYB down there as I pull started it (Not easy :-/)... I got a few pops, but no go.
Note, all of the above was done with the muffler removed. I recognise in hindsight that this may have been an error, as the pressure waves going back into the block from the exhaust may have been necessary.
At this point, I'm thinking 2 things which I haven't tested:
1 - Yes Norm, I agree, it could be a carby issue and if anything considering it's new and the assembly shouldn't be worn, I'm assuming it may have to do with the needle & seat along with the float valve, however, to get one of those awesome ones from the UK may take time. If they're that awesome I may get them in bulk as you did which would drop the price per unit down to around $2.50 but would still mean I need to spend $250 to get that value haha.
2 - The back-pressure which wasn't available due to the muffler not being installed was stopping the mower from firing.
I'm hoping to test further tomorrow, the muffler is the quick and easy test so I'll try that first, probably with the fuel supply disconnected and with a decent supply of SYB down the snokle and in the spark plug hole, and if that doesn't resolve it I'll take apart the new carby and check the needle & seat and see if I can find anything there.
