There is no "psuedo-compression" release. The exhaust valve cam is made to hold the exhaust valve slightly open to release some pressure as the piston comes up making the engine easier to crank. The valve closed just before combustion to provide full power. If the valve lash is too much the exhaust vale closes completely and the rope pull will be difficult. A starter motor will turn very hard and may not crank the engine. Many a starter motor has been replaced and the new motor may work for a time, but the problem comes back. Accurately adjusting the valves solves the hard crank problem. The new cam was designed to make cranking easier. Once the engine is running, the compression release isn't long enough to matter.
Hammermechanicman
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If we are talking about a 5hp 13xxxx series briggs engine the "easy spin" bump is on the intake and not the exhaust. If the engine is not burning oil the most common cause of carbon deposits on the plug is not running rich but rather not running the engine hard enough to get the spark plug into the self cleaning range. The later engines were fixed main jet and unless the air cleaner was clogged it is very hard to run the engine too rich. Unless the engine is run hard enough to get the plug electrode to at least 900 degrees F the plug will carbon foul.
I took the head off and observed some light scoring at one location in the cylinder wall. Soaking for a day or so with Marvel Mystery Oil I got the piston moving freely again. I reassembled and ran a few start/stop cycles. It froze up again. I drained to oil and am now ready to remove the side cover.
Any tips on removing the side cover without butchering the gasket? There appears to be two Alignment Dowel/pins..do I light hammer tap on these? Also why are there 2 Oil Fill locations on this engine? One fill location is practically inaccessible on the assembled Tiller...blocked by Carb and Drive Belt cover.. thanks for ongoing help.
Any tips on removing the side cover without butchering the gasket? There appears to be two Alignment Dowel/pins..do I light hammer tap on these? Also why are there 2 Oil Fill locations on this engine? One fill location is practically inaccessible on the assembled Tiller...blocked by Carb and Drive Belt cover.. thanks for ongoing help.
Your last post shows you’re in way over your head. What are you looking for by removing the crankcase cover? Chances of removing the cover without damaging the gasket are next to zero. You also must clean the crankshaft, or you’ll ruin the seal. If you are not careful you‘ll have tappets on the ground and will need the check valve clearance when you try to reassemble. My recommendation, stop and find a good tech.
Good info:
AS Rivets says
AND you are whipping on a dead horse. Time to throw in the greasy towel on that one. It's a good thing to get the model, type and code from old or any engine FIRST (if it's not rusted so bad to be visible and sometimes a Bubba has installed another air cowling and the ID info does not even match the engine) and then look online to see if replacement parts are even available and if so the prices. Several of the old Briggs parts are NLA or if available will cost more than a NEW replacement engine.
Look at the $100 Predator engines from Harbor Freight or I quite often I find really good engines on Pressure washers that have a bad pump for around $25.
AS Rivets says
AND you are whipping on a dead horse. Time to throw in the greasy towel on that one. It's a good thing to get the model, type and code from old or any engine FIRST (if it's not rusted so bad to be visible and sometimes a Bubba has installed another air cowling and the ID info does not even match the engine) and then look online to see if replacement parts are even available and if so the prices. Several of the old Briggs parts are NLA or if available will cost more than a NEW replacement engine.
Look at the $100 Predator engines from Harbor Freight or I quite often I find really good engines on Pressure washers that have a bad pump for around $25.