Lawn Boy 5214 D409 w/ D600 modular plastic carb - no start, hose and oring sizing

Hello,
Just acquired my first Lawn Boy, a 5214 with D409 engine with the later production D600 modular plastic carb to tinker with. Observations so far:

-Gas tank/shroud has a couple of very small splits where the tank meets the shroud, hoping to fix those with epoxy
-Primer bulb is aged but still pulls vacuum
-Primer line was shot. Tried some 1/8 vinyl tubing heated up and was just barely able to get it over the nipple on the carb and primer bulb
-Fuel line is a little hard and short
-Coil and points were rusty, cleaned those and gapped assembly with business card
-Spark plug is RJ12c instead of the factory recommended CJ14. Plug is cleaned and gapped to .025 per spec
-Oring sealing carb to reed plate is failing, appears to be slow seepage between carb and engine
-Engine rotating assembly is not binding or sticking and has the expected slight resistance with piston movement
-Mower will not pop or start. Primer bulb causes fuel line to fill with fuel but not the primer line

I am assuming the carb needs a cleanout as I can see floaters in the gas tank. Previous owner claimed it ran the year before but we all know how that goes. At the least I want to do new primer and fuel hoses, new carb oring and disassemble(CAREFULLY) the plastic carb and clean.

Does anyone have any other tips for getting this old beast running, and does anyone have the Oring size for the carb to plate mount and the correct diameter of fuel and primer line that does not have to be heated or stretched to fit (very nervous about the plastic nipples on the carb)

Is there a cheater/witness mark somewhere on the rotating assembly for matching TDC with blade orientation for proper balance as I've read is necessary?

Thanks!

If the mower is worth saving I may also be in the market for a 679710 metal carb with reed plate as an upgrade to the plastic fantastic, if any of you have one in your parts hoard that you'd be willing to send up to Canada.

pessimism said:

Hello,
Just acquired my first Lawn Boy, a 5214 with D409 engine with the later production D600 modular plastic carb to tinker with. Observations so far:

-Gas tank/shroud has a couple of very small splits where the tank meets the shroud, hoping to fix those with epoxy
-Primer bulb is aged but still pulls vacuum
-Primer line was shot. Tried some 1/8 vinyl tubing heated up and was just barely able to get it over the nipple on the carb and primer bulb
-Fuel line is a little hard and short
-Coil and points were rusty, cleaned those and gapped assembly with business card
-Spark plug is RJ12c instead of the factory recommended CJ14. Plug is cleaned and gapped to .025 per spec
-Oring sealing carb to reed plate is failing, appears to be slow seepage between carb and engine
-Engine rotating assembly is not binding or sticking and has the expected slight resistance with piston movement
-Mower will not pop or start. Primer bulb causes fuel line to fill with fuel but not the primer line

I am assuming the carb needs a cleanout as I can see floaters in the gas tank. Previous owner claimed it ran the year before but we all know how that goes. At the least I want to do new primer and fuel hoses, new carb oring and disassemble(CAREFULLY) the plastic carb and clean.

Does anyone have any other tips for getting this old beast running, and does anyone have the Oring size for the carb to plate mount and the correct diameter of fuel and primer line that does not have to be heated or stretched to fit (very nervous about the plastic nipples on the carb)

Is there a cheater/witness mark somewhere on the rotating assembly for matching TDC with blade orientation for proper balance as I've read is necessary?

Thanks!

If the mower is worth saving I may also be in the market for a 679710 metal carb with reed plate as an upgrade to the plastic fantastic, if any of you have one in your parts hoard that you'd be willing to send up to Canada.

Click to expand...

First of all, your model must be may be unique to something sold in Canada because I could not find an image for a 5214. But I have a 7260G that is equipped with the modular carb. I cannot say if I know of any adaptation for another type of carb.

Anyway let’s start with the basics. Have you tested it for spark? Perhaps it needs a new coil or at least a workable one from a donor mower. Make sure the points are clean. Is it getting fuel? Clean out the tank and replace the fuel line, the primer line, and clean that carb. Even a tiny speck of garbage can prevent a mower from starting. It may also be gummed up from sitting. I would also replace the needle and seat and adjust the float while you are at it. Just make sure that every jet and passage way is clean and clear. You mention something about the O-ring size for the carb. Do you have a hardware store nearby that has a selection of various O-rings? Take your carb along and find one that is a suitable fit. When you install it, make sure you have the govorner set up properly with the throttle in the correct position. The throttle lever should be angled toward the reed plate, not the air cleaner. While you’re at it, make sure that the flywheel keyway is not sheared off. On an engine that old, I automatically replace the crankshaft seals. Leaky, old seals will make starting either very hard or impossible.

Are the exhaust ports plugged with carbon? If so, clear them out and do the same the muffler. I have revived a few Lawn Boys by simply cleaning out the carbon. If it can’t fart, it can’t breath and vice versa.

As far as finding top dead center, I just rotate the engine while looking through the exhaust port and then file a mark on the end of the crankshaft.

Those little two-strokes are so simple. If you can’t get it to pop, it’s usually a small problem that needs to be solved. All it needs is air, fuel, and spark—all at the right time and at the right amount.

Couple things I've done to start a two stroke over the years. Hit it with a good shot of starting fluid in the spark plug hole, put the plug back in and try it. And if you can see the nut that holds the flywheel on you can spin the motor with with a drill and socket, check direction of rotation of course, pull the drill away when it starts firing with the drill still running, can start a stubborn one with this usually. And check to see if the plug is getting wet when starting, easy to flood a two stroke, hard to clean out.

I just realized that one of my points mentioned about replacing the needle and seat is not quite the same with the modular carb. On the modular carb, the needle is combined with the float and is not a separate part. Replacing it would mean that you would have to find a new float—which may prove difficult. I just wanted to clarify that.

Here is a photo of the float.

Yes, I believe it is a Canadian specific model. Thank you for all the suggestions, the drill as starter trick is a good idea.

At the moment I have the engine out and partially torn down. Had to invest in a 3 jaw puller to get the upper blade adapter square off the tapered shaft, sounded like a gunshot when it popped loose.

I ultrasonically cleaned the carb. No cracks or damage in the plastic. Cork float looks ancient but seems intact. Needle and main orifice are clear

I'm making the carb new gaskets from a thick shoebox so I can get it to a point I can start test it, the bowl and reed plate gasket were rock hard and broke on disassembly, one looked to have been (badly) patched with some silicone at some point. The reed plate does not sit flush against the engine body even after cleaning the mating surfaces, so I suspect it may be warped and why silicone had been added. The carb oring I thought was bad actually looks fine, i think the seepage was from the gaskets and not the o ring.

The air filter cover has a small hole and several cracks from some sort of impact, going to patch and epoxy that.

There is an inch wide hole in the muffler bowl underneath I'm going to patch with a tin can and a few screws for testing. Grass had gone through the hole and partially filled the muffler, and there was some grass inside the head around the piston arm.

The section of the bottom of the piston with the cap with the two nuts and foldover tabs, has some play in both directions. Is this a sign of heavy wear or is there supposed to be some slop in that mechanical joint there? The piston itself looks to have good compression as there is a solid "whoosh" turning it over by hand.

Do you know the hose sizes for the primer line and fuel line? Fuel hose is rare as hens teeth locally and the few hardware stores that stock it charge an arm and a leg for 1-2 feet of thick, non pliable rubber hose that is so stiff I fear I'll snap off the plastic nipples trying to get it on and secured both ends. ebay has plenty but in at least a half dozen ID/OD combinations and wall thicknesses, and there seem to be two routes to go, thick rubber and clamps, or thinner clear plastic/heat/stretch without clamps? I'm stalled at this point without fuel and primer lines as the ones on there were completely hardened and starting to split.

Teardown revealed more rust on the coil I couldn't see with the flywheel still on. Will get that cleaned.

If I can get the thing to spin under its own power even briefly I will call this a win, even if the mower is too worn out to save. For $50 I am learning a lot and they sell 3D puzzles for more money. I'm an IT/computer guy and do my own automotive work (space and tools permitting) but haven't forayed into small engines before.

pessimism said:

The section of the bottom of the piston with the cap with the two nuts and foldover tabs, has some play in both directions. Is this a sign of heavy wear or is there supposed to be some slop in that mechanical joint there? The piston itself looks to have good compression as there is a solid "whoosh" turning it over by hand.

re.

Click to expand...

I think this is the rod and cap. Side to side play is common here. Might cause some noise if worn but engine should still run. Fuel line to carb is usually 1/4 inch. Or 6mm inside dia.

The correct fuel line size is 3/16". The easier to find 1/4 " hose will slip on and off too easily, you can secure the hose with a tight fitting sping hose clamp. The primer line is 1/8". Best to use the black style rubber fuel rated hose. For the carb mounting o ring, unless cut or cracked, I just apply silicone grease to the carb's o ring base. Try not to Distrib seals and gaskets. It softens the o ring and prevents air leaks. When it comes to buying parts. Generally there not available, in most cases I look for simmilar mowers on kijiji and use what I need.

I have several LB all with the D409 engine. I figure not replace the crank seals unless the are leaking of course. If you find a pool of oil under the flywheel at the points location, then change the top seal. Same goes for under muffler cover area. I always clean old oil with brake clean spray and recheck after several hours of operation. Make sure the reed plate sits flat and with the stamping marks away from the reed plate cover. Different style floats were used in the plastic carbs, plastic and cork. I try not to open the engines. Like the previous poster said, these are simple but well made engines as long as you keep them clean, lubed and you have spark they will run. The neighbours get a kick out of me using my 40 year old mowers.

Where are you located in Canada , I have spare parts .
I'm in London .