The HM 80 is a great engine (for a Tecumseh ;0) The long intake complete w/ elbow lend itself to a few quirks tho. Yes, it does have a compression release, but it is dificult to know pulling over a chipper. I would say get some more time running it, maybe some of your favorite witches brew in the oil/ fuel to clean the engine up a bit more especially if it is low use. Seems like a geat deal.

There is collectively more knowledge here at GW than one could use in several years. The hitch is that along with knowledge held by each individual,there resides contrasting opinions on how to apply said knowledge. I reccomend contacting the local state or city ag agency where you will find litature composed by teachers in format that is easy to follow and understand. I for one would love to see updates and pics as the program progresses. No matter how old or long it's been since last post,threads bump to the top with each new post. There may even be GW folks nearby that want to assist the teacher after you and your classmate moves on.

hello HU-407961074 I am not going to read through all the comments above. Hope you have tried their suggestions. This is long. The original part number is 394891. B&S changed the part number to 590781 when they switched to a chinese supplier. The retail price for this item is close to $60.00. All the cheap armature ignitions on the internet may work ok, but I don't know. The original ignition seldom fails. Mice destroyed your sparkplug wires. Another failure occurs when the key switch fails and voltage is introduced into the armature coil shut off wire. When the key is turned off, the shutoff wire should be connected to ground only. Any voltage will instantly destroy a new armature coil. Corrosion on the mounting post and mounting screws is another problem that will cause loss of ignition. A shorted shutoff wire will also cause a problem. When installing a new armature coil, clean the mounting post to insure a good connection. A small wire brush will work fine. Make sure there is no corrosion on the armature laminated stack. The mounting screws must be clean. Direction of installation is marked on the armature coil. With the armature pulled away from the flywheel, tighten the screws. Rotate the flywheel until the magnets are next to the armature. Install a spacer (.008 - .012) between the armature and the magnets. A business card will usually work. Loosen the screws and the armature will be attracted to the magnets. Tighten the screws. Remove the card by rotating the flywheel. Feed the ignition wires to the sparkplugs but do not install. Leave the shut off wire disconnected. Connect the sparkplug leads to an air gap ignition tester. The tester should have a .166 gap. Approximately 13,000 volts is needed to jump the .166 gap. If you do not have the proper tester, make your own. Connect the ignition tester to the engine block - not the spark plugs. NOTE: The glow light ignition testers do not always work well, so do not use. These will glow at a voltage too low to start a small engine. You can test for ignition now - even with the blower shroud removed. You will need to hold the oil filler in position so it does not blow out. Care is needed with a rotating flywheel. Look at the spark tester for ignition. A spark can be blue, amber, or invisible. A darken area may be needed when performing this test. Before connecting the shut off wire, you must insure the key switch is not feeding voltage and that the off position connects to ground. Install the blower shroud. Sparkplugs may have carbon or oil on the porcelain. This may form a carbon trail for the voltage to follow and you will never see a spark. A crack in the porcelain will also cause loss of spark. If your flywheel key is sheared, the engine may not start due to incorrect timing, however you should still have spark. If the engine does not start after ignition is restored and timing is restored, ask questions.

The top of the rad being very hot, but getting cold within the first 5 inches tells me you have little to no coolant flow. Was this a shop you took your car too or not? One not to uncommon mistake that the person doing the work could have done is he may have accidentally installed the thermostat backwards, or it could simply be defective. The thermostats job is to control the coolant flow through the radiator once the engine reaches a minimum temperature. Another not so common but potential issue could be that the wrong pump was used and its impeller is being spun backwards. Some pumps are driven clockwise, and some are counter-clockwise depending on how the belt runs the pump. Parts suppliers today are much better about not making this mistake which a mechanic would not easily catch because the impeller isn't always visible. Lastly, the head gaskets were replaced, but were the heads sent out to be tested by a machinist while they were off? The original failure could have caused one or both of the heads to crack or warp, and they might have needed to be replaced. If they have simply warped, they should have been machined back flat while they were off. (which actually requires a valve job too) Either way, cracked or warped you may still be getting combustion gasses into the cooling system and that can be preventing proper coolant flow through the radiator.