Hi Jeff, I am completely stumped with these, can't remember how many I have worked on and everyone of them has caused major issues. Belt tension is not the problem and on it at the moment it only has the spring tension that sits in front of the motor on it. This one here at the moment is the one that was kicking back savagely and I eventually fitted the decomp with the restrictor and that solved the problem. On the 2 motors I fitted today I used that same decomp valve, might try a different valve in the morning and see if that gives me kickback. That is about the last thing I will try on it, I have already told him I can't fix it and to come and pick it up. It is in good condition bodywise, but just fitted with a motor that is not suited to the design
I sent a good sidepull fc with the 24 when it went to Eden He sees no reason to change back yet. It would be easy to do we have the sliding plate just no tensioner assembly.
If he ends up wrecking I would be interested in parts or all of it. I need a blade carrier ,a genuine belt and a spindle would happily take the whole thing but how would we get it to Eden.
Hi Jeff the PT pulley is very simple and I'm pretty sure that they could be used on the F/C's as well. This means you don't need the taper pulley they fitted to the F/C's, just leave the boss on and bolt the pulley up using the standard washer and nut. Might have to adjust the motor up a bit to compensate What diameter is the aircon pulley? If I am going to have to fit F/C's to the later bases then I will need to get a number of adapter plates laser cut because it is too time consuming making each plate by hand. Now I am really on the hunt for as many F/C's as I can find I wonder if these pulleys are still available they shouldn't be too expensive, they are only a pressed metal one, like an automotive waterpump pulley
That certainly is a heavier one. What is that off?an edger or something without a blade disc. I wonder if it would help much as there is no weight out wide like a blade disc. I have never seen one like that
In my case, not sure about Norm's we are not using an original PT 24 engine Maybe the real engine has something like that even a heavier flywheel as we have talked about before
I'm sure the kickback is an inertia problem If you switch off the ignition no kickback so the engine is definitely trying to run backwards. My scenario is that because of the belt etc the engine is hard to get turning properly and it stops on a compression and unfortunately fires as the piston falls back hence the kickback.
More weight under the engine might help even and ordinary blade disc if it would fit without blades. You could then leave the belt looser.
We give ours a hell of a pull trying to get it it to turn properly. The PT starter really locks on to the crankshaft and won't come off easier like a full crank.
A heavier mass on the crankshaft carries much more momentum this momentum helps to keep the engine running at a steady RPM as you add load to the motor.
This heavier mass will help to spin over a higher compression motor when starting.
You could also try lowering the compression with a decompression plate and 2 gaskets and see if that helps to spin the motor over quicker so it doesn't kick back but you may loose a little power .
I don't think a small power loss would matter much. The 24s power comes from the big heavy blade disc. Once it gets a few revs up it will go through almost anything.
I'm convinced that the gearing on the PT pull start is not able to spin the motor fast enough to get it to fire, it just seems too slugish for it to start. They are a piece of shite on a 24,probably why you don't see too many around
Don't know Jeff, but they don't seem to spin fast enough to be able to fire, feels heavy and sluggish and before I gave up I had removed most of the tension on the belt and still nothing
Hi Jeff, I can't even get a splutter out of either motor, even with starter fluid, pull them off and put back on a standard base and they will fire up first pull. I have had this problem with everyone of these 600's fitted with the PT motor. Fuel is new just mixed it, belt and spindle seem fine, I do have shoulder issues that have developed over the last few months that doesn't help but on a standard base no problems starting them
Well they do need a stronger pull than a standard PT. Maybe try to find your local strong man and give him a go I'm lucky I have such a bloke for a neighbour. Heeps stronger than me. If he can't get it go then it's cactus.
Hello NK, MW and JFB, that's where a key start PT might come into it's own.
What do I need, apart from a pulley, to transfer a 160 from a cracked Mayfair base to the Super 24? I want to build one in case I need to bring out the big guns which I may need down the track.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
Hi Jeff, I built an F/C one for this bloke last week and starting that was not a problem. I am 100 % convinced the PT on these is a dud design, great motor, great base but for some reason the combination does not work. No idea why yours works so well. MF, Good idea but you can't fit the starter motor because the belt tension adjuster bolt pushes on a plate where the starter motor would be fitted. The other issue is these machines often only get used a couple of times a year to clear blocks so every time you went to use it the battery would be flat. Apart from the pullet you need the adapter plate that bolts onto the motor and that then bolts to the 2 slots in the base so you can adjust it in and out.. I guess the ring with a piece of threaded rod welded to it that is used to adjust the belt tension is missing but that is not a big deal you can get around that easily.
The proper pulley for an FC is going to be hard to find. I have never seen one but Norm says it's the boss with the tapered fitting as well Mine has a modified automotive pulley for a 11mm fan belt maybe off an an air-conditioner compressor or something
I am using an 11mm fan belt as well Commodore or something I think . Conventional wisdom suggests that only the genuine Victa belt will last in this application but this one has done 2 years of reasonably hard work.
Norm I have had that sluggish pullover before It was usually after the engine has been on its side or upside down. The remnants of the oil l must run around the rings or something Usually clears after a few pulls with fuel off and plug out or something.
Hi Jeff, I wouldn't try to find the correct F/C pulley, I would try the pulley of a PT or as you used the aircon pulley although I think you might have to lift the motor slightly to get the belt alignment correct. I found an aircon one on ebay yesterday but it was about $30 and the hole needed to be bored a couple of mm. Yes that is what the motors feel like, they won't spin freely as they do with the blade carrier bolted directly. You have to get that big blade carrier spinning and that is where the issue is. I was thinking that with the sidepull it is geared and that might help, but I have also built a couple with the cup pull start and they spun over easily. I'm fairly convinced the problem is somehow related to the PT pull start design even though it is a very clever design, somehow I think it is geared too high for this application. The pic is the adapter plate that MF will need to bolt an F/C to the base
I think the kickback issue is related to the PT pull starter design. It seems to really hang on to the crankshaft and does not disengage easily like the FC types.
Yes Jeff it has to be something like that, it just doesn't seem to be able to get it over that last rotation. Only other time you will get a kickback on a standard mower is if the blade carrier is loose or not fitted. This is a different problem but I think it is weight related in the fact that you can't get it spinning fast enough before it hits that last compression stroke. I have never had the kickback on a 24 fitted with a F/C This is the pulley I found, bit expensive though https://www.ebay.com.au/itm/Pulley-Add-On-for-Swp-SB-Air-Conditioning-Chrome-Steel/162694411127
The one I have is solid cast steel I just needed to turn it out to the right diameter to fit over a PT blade boss. It fits an FC as well. There is a recess nearly the right size on the other side. My guess is it came from a wrecking yard I just left about 3mm in the middle and filed a couple of slots in that to fit over the prongs on the blade boss.
On that eBay one you would have to turn up some kind of adaptor
I think an FC on a PT 24 base might have height issues The engine could be too high I needed to lift my PT by 20mm. With the opposite conversion need to lower by 20mm
Yes, forgot about that, there is a least 3 different base/slot types and I was looking at the adapter plate pattern I have here. You have me intrigued now, I have a number of F/C bases here that I was thinking of converting to PT bases. I'm picking up another 30 PT motors tomorrow so that means I will need a lot of bases, then the dreaded bit, wheels
I did that when I was converting my FC 24 to a PT motor.
The material is a bit thin and I needed to weld some bits on to give me the slots but it worked.
I intended to get something that worked fairly quickly then use that as a pattern to cut out a proper one from 6mm plate But it worked so well I didn't bother. I did have to brace it a bit later to stop it bending when the belt tension came on.
There seem to be a few different types of FC 24 bases Some do not have the sliding plate the early ones I think.
I did all this because FCs are hard to find around here I did get on to a couple later on however.
Jeff
Last edited by jefffrombrisbane; 28/12/2010:25 PM.
I checked my stockpiles of F/C motors yesterday as I will have to start rebuilding them. I have about a dozen side pulls and probably the same in cup starters but with these I am short of the pull starters, only have a few of those.