Well that is my motor:thumbsup:drinkup Never even thought is had a blower. I was looking for some thing like my JD turbo not some thing can of buried in close to the block :Banghead
ointhead. I like the sound of it better than the JD and it seems faster in the rpm department and seems like the machine is slightly faster.
How do you measure wear or performance on the engine for wear without being invasive to the engine? Sucks
I just changed the oil & filter again and put 15/40 Valvoline in it.
From what I googled it is a very old design from near WWII. I guess it is not still made? If so when did it drop out of production?
Speedpup,
Welcome to the wonderful world of the old Detroit "green leaker". Your right, there's nothing like the sound of a Detroit. My favorite was driving cranes that had the 6-71 and have that thing pegged out pulling a grade. Man what a sound. I think the last production model of the 2 stroke Detroit was the 8V-92T, somewhere around 1995. The engine just cannot meet the modern emmision standards of today, but the parts are still available and probably will be for a long time as there's still a lot of them out there. I wouldn't worry too much about your "just changing the oil", since you seem to do it quite frequently anyway, long before the oil breaks down. Just start using SAE 40 on your next oil change. As for wear/performance, we can't expect your engine to operate like a new one, as it's obviously not. But we can say this; a good Detroit with good compression doesn't have to crank long to start. A good/tight Detroit will fire off fairly quick when start is engaged. A new properly built Detroit will smoke very little if any, even when cold. Aged engines will white smoke a little when cold, but should clear up when warm. Oil useage is important on aged Detroits. Excessive oil useage indicates bottom piston scraper rings are bad. They allow a small amount into the air boxes (Detroit terminology) to lubricate the top piston rings, but exessive amounts mean they're worn. That's when you'll see excessive oil coming from the air box drain tubes and leaking onto the ground. My point is with the Detroit engine; as long as it doesn't "smoke everyone off the jobsite", starts fairly quickly, and doesn't use a ton of oil, you've still got a few years on her. Now that you recognize the "blower", I'll describe to you just what it is and why I said "it can't run without it". It's similar to a supercharger, but it's not a supercharger. It's what's called a "roots type blower". This engine is a two stroke engine, meaning, it doesn't have an intake stroke or an exhaust stroke. It only has a compression stroke and a power stroke. How can it do that??? Well, that's the blower. The Detroit cylinder has air ports at the bottom of it. The piston goes down below the ports, exhaust valves are open, fresh air is "blown" into the cylinders via the blower which removes exhaust gasses via open exhaust valves. Exhaust valves close, blower puts charge of fresh air into cylinders. Piston goes up, blocking ports, compression begins. At top of compression stroke, fuel is injected, piston forced down, power stroke. At bottom, ports open, exhaust valves open, we begin again. 2 stroke engine. I know this is a long post, buy hey, it's Friday night, got nothing better to do, and it's addressed to you. Just thought you might like to learn a little something about your green leaker. We affectionately call them this because they do leak oil. A fellow asked me once "how do I get my Detroit to not leak oil?" I replied "I wouldn't worry about it if it leaks oil...I'd worry if it didn't, because it doesn't have any oil!" I Hope your old Detroit hangs around for many years, your living old school in a modern world.
