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So I have two old blowers that run pretty well. However they have almost no compression. one is 60 lbs the other like 75#'s. My dealer told me that they were designed for leaded gas and since there is no lead now to add a little 2 stroke oil to lubricate the top end. Ive been running them on 100/1 synthetic 93 octane. Will a valve job increase me compression and running reliablility? How hard is it? I have never oped up one of the but I do rebuild chainsaws from the cases up. Any thoughts of wisdom. They do die in the heavy snow and I want to power through that crap. The one with the lower compression actually runs better than the higher one but I have to keep playing with the carb on the bigger one to keep it running sometimes. They also both burn a dipstick oil on every tank from full to add. Thanks for the help!!!!
 

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put a predator 212cc on them and be done with them. those engines are not worth fixing beyond carburetor issues, you will spend a lot of time repairing internal issues
 

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If that's an H60, specs are 0.008" to 0.012".

lap the valves and throw-on a new head gasket and it will run like new. It's definitely worth the minimal effort/expense that it requires. I've done 4 (soon to be 5) L-heads this winter.

While you're ordering you may also need breather gaskets & the intake-pipe gasket as well.
 

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Discussion Starter #7
What is "lapping the valves"? Also I dont see anyway to adjust "valve lash", easy to do on a car, but I dont see anyway to adjust. Thanks!!
 

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What is "lapping the valves"? Also I dont see anyway to adjust "valve lash", easy to do on a car, but I dont see anyway to adjust. Thanks!!
Ah, there are a few youtube videos on it...very simple.

Grab a lapping tool...basically a dowel-rod with 2 different sized suction cups on each-end...you want the small one. And grab some lapping compound. Remove the valve, smear some lapping compound on the valve-seat area of the valve...being careful not to get any on the valve stem (or anywhere near the cylinder/piston!) then spin the valve with the lapping tool like you're trying to start a fire. It's important to clean-off all of the lapping compound when you've finished...I try to get as much of it up with dry rags as possible, then use a solvent on a rag to remove the remaining.

If you don't have enough valve clearance, you may need to remove some material from the bottom of the valve stem before lapping. I always adjust clearance 1st (I use emery paper and cutting oil) and shoot for +0.001" above the middle of the spec range (so for 0.008-0.012, I shoot for 0.011...then lap to 0.010").
 

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So I have two old blowers that run pretty well. However they have almost no compression. one is 60 lbs the other like 75#'s. .....
The one with the lower compression actually runs better than the higher one but I have to keep playing with the carb on the bigger one to keep it running sometimes. They also both burn a dipstick oil on every tank from full to add. Thanks for the help!!!!
Based upon the very high oil consumption your engines are worn out. The worn piston rings are likely the cause of low compression and poor engine performance. You can check this by putting a little engine oil into the spark plug hole to temporarily seal the piston and checking the compression.

Also check for oil at the crankcase breather pipe. A worn engine will allow engine combustion pressure to leak past the worn cylinder bore, piston and rings to pressurize the crankcase. This blow-by will force oil out the breather and lead to high oil consumption.

You will probably need to rebuild the engines or re-power with new engines.

Good luck.
 

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I would not try to adjust the valve clearance and definitely do not try to lap the valves if you are not an experienced mechanic with the knowledge and experience working on 4-stroke motors. I cant tell you how many times I have seen engines ruined or had to fix backyard cowboys eff ups during my many years as a professional mechanic. Let someone fix it who knows what they are doing and is confident at it or just order a new engine.
 

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Discussion Starter #12
New motor is not an option. I'd rather kiss my sister. I can fix anything. I was going Harley transmissions when I was 17 I think I can handle a B & S just never did one is all. I built 6 Stihl saws this winter from the cases up and dozens of sled motors. I am unemployed, I have the time, I'll spend 50$ on parts and fix it with all your good folks help! Thanks!!!!
 

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I would not try to adjust the valve clearance and definitely do not try to lap the valves if you are not an experienced mechanic with the knowledge and experience working on 4-stroke motors. I cant tell you how many times I have seen engines ruined or had to fix backyard cowboys eff ups during my many years as a professional mechanic. Let someone fix it who knows what they are doing and is confident at it or just order a new engine.
If the engine is at the point of replacing, he has absolutely nothing to lose by trying and learning a few things along the way. There are plenty of youtube videos and enough experience on this forum to help with all aspects of an engine rebuild. At some point it may be cost prohibitive to buy and replace every part, but I would encourage him to try and repair the OLD engine for the experience and confidence gained. We all have to or had to start somewhere. :D

We were typing at the same time. I see that you are more than qualified to do the repairs and look forward to your progress. This is a Briggs motor? If you post the model and spec number, I may have a service manual link to help you.
 

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Town picked up on the point of oil consumption.

A leakdown test would be a good thing to do before breaking it down.

Other things that can lead to oil loss through the breather are are overrevving (chk your rpms) & any breaks in crankcase sealing (like a cracked filler tube.)
 

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Town picked up on the point of oil consumption.

A leakdown test would be a good thing to do before breaking it down.

Other things that can lead to oil loss through the breather are are overrevving (chk your rpms) & any breaks in crankcase sealing (like a cracked filler tube.)
A leakdown test is the best way to determine cylinder sealing. The compression release will lower the psi numbers so not a true indication.

There seems to be two camps here, fix the original engine, or replace with china made product.

I'm all for repair rather than replace.
 

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So I have two old blowers that run pretty well. However they have almost no compression. one is 60 lbs the other like 75#'s. My dealer told me that they were designed for leaded gas and since there is no lead now to add a little 2 stroke oil to lubricate the top end. Ive been running them on 100/1 synthetic 93 octane. Will a valve job increase me compression and running reliablility? How hard is it? I have never oped up one of the but I do rebuild chainsaws from the cases up. Any thoughts of wisdom. They do die in the heavy snow and I want to power through that crap. The one with the lower compression actually runs better than the higher one but I have to keep playing with the carb on the bigger one to keep it running sometimes. They also both burn a dipstick oil on every tank from full to add. Thanks for the help!!!!

sounds like the rings more than a valve job. but a valve job would help too.

just pull the piston/rod, hone the bore, put new rings on, then run it in, the compression should go up

these don't have a lot of compression to begin with, they are low compression engines, made to start with a pull rope, because of that they can't put the same compression in as a 2-stroke. it would rip the rope from your hand and break the rope. a 2-stroke basically leaks a lot of compression by design, and doesn't become efficient until very high rpm. so it can get away with a higher static compression and still be able to pull start it.
 

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I agree with classiccat and scrappy. A leak down test would be the best diagnostic tool in your situation. As greatwhitebuffalo stated, these engines are not high compression and 60 to 80 psi compression is not a bad reading. The oil consumption is a concern and could be caused by worn rings, blocked drain hole behind the breather cover, worn valve guides or the oil level to high.
 

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Discussion Starter #18
I stated Briggs and I should have stated Tecumpsah. my bad. Also I'm running standard 30 wt in the cold and I guess I should be running 5/30 wt. These machines are both throwing snow 40' so were really not in bad shape to begin with, really,.. Just asking about valves, lets keep it simple. I'm not putting a china throw on these things, I like old stuff. I drive a rust free mint 86 Chevy K20 4X that will blow away most new trucks out there. I love the 7/24 cause it fits through both my doors and I can wheel it into my 80 degree shop and make it right. Thanks for all the help!
 

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Hey thanks for that. Im going through the videos now, seems straight forward enough. Winds up I just got a call I have to do a 377 ski safari motor tomorrow so that will slow me down a bit but no snow in the 10 day forecast and I still have one runner even if I dissemble the other. Thanks for all the help everyone its really appreciated!!
 
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