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Does my mower engine have valves or not

#1

L

Lennie11b

I have a 94 mtd with a 16.5 b&s twin 2 ic it is hard to start and I have looked around and can't find any valves to adjust so does anyone know if this engine has valves


#2

exotion

exotion

Woo engines have valves... Either ohv or inside


#3

davbell22602

davbell22602

The valves are under the cylinderhead. You have Lhead twin engine.


#4

Mike88se

Mike88se

Yep... gotta have those valves ;) I adjusted the valves on a 12.5hp Briggs IC from the same era. I guess they were what exotion called outside. Best I recall: 1. Find valves. 2. check clearance. 3. if not in spec remove and file stem end. 4. recheck clearance. 5. if not in spec repeat 3. repeat until clearance is in spec. I was told that perfection was not required. Some even disagree on what spec is for the intake valve.
Kinda crazy way to do things. The "keepers" were a minor PITA to reinstall.
Hopefully a more knowledgeable person than myself will come along and contribute. exotion prob knows more
There are helpful vids on youtube.. try donyboy


#5

L

Lennie11b

davbell22602 said:
The valves are under the cylinderhead. You have Lhead twin engine.
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Kinda new to small engines how big of a job is this and whats the steps to do this it might not be the valves my engine will turn over slowly with the plugs in but with the plugs out it will turn over fast like its supposed too so valves is what im guessing


#6

davbell22602

davbell22602

Does your oil smell like there's gas in it. Might be starter or battery issue?


#7

exotion

exotion

Lennie11b said:
Kinda new to small engines how big of a job is this and whats the steps to do this it might not be the valves my engine will turn over slowly with the plugs in but with the plugs out it will turn over fast like its supposed too so valves is what im guessing
Click to expand...

Your kind is kinda difficult imo I like overhead personally if your inexperienced you might wanna consider hireing out


#8

L

Lennie11b

I bought this mower to learn small engine repair im actuallu making it into a off road deal so I up to anything how do I start pull the engine or can it stay in any websites explaining this


#9

reynoldston

reynoldston

Lennie11b said:
I bought this mower to learn small engine repair im actuallu making it into a off road deal so I up to anything how do I start pull the engine or can it stay in any websites explaining this
Click to expand...

Nothing wrong with learning small engine repair. To do so I take it you have a good set of tools. If you don't know the different between a 2 cycle engine (no Valves) and a 4 cycle engine (valves) I would say go to the library and get a book on small engines and repairs. A earlier post gave you a good description on what you have to do. To adjust valves on a L head engine it has to come apart. Which mike88se already told you how to do. The library book will give you a good description with pictures.

The best of luck with this.


#10

davbell22602

davbell22602

Here's a link to Briggs Lhead twin engine shop manual.

http://dl.dropbox.com/u/12502267/B&S Service Manuals/02_271172TwinCylinderLHead.pdf


#11

Fish

Fish

Two things are common in the l-head twin that cause hard cranking. First, the starter's top bushing gets worn out and gets a lot of slop in it, I replace the bushing
using an oilite sleeve from the hardware store and a little bit of redneck craftsmanship. While apart, buff the contacts of the starter.

The other issue that is common, is a buildup of carbon in the combustion chamber, which just requires the removal of the heads and a stiff wire brush, the gaskets
will likely come apart, so those would need replaced as well.

It is highly doubtful that a valve adjust would cure your problem in this instance, it mainly applies to the OHV models.


#12

I

ILENGINE

Starter problems are fairly common on the Briggs opposed twin engine. there is just so much stress on the starter, mainly because of such a small starter turning over so much mass. I have had several over the years that would be hard to start or would turn over slowly, like you describe. cleaning the brush area of the starter may help, but may also require the starter to be replaced.

Carbon buildup in the head area is also a problem with that engine. but valve clearances are usually not a problem with that engine, other than the valve seats coming out of the block. The opposed engine has some cooling issues leading to overheat of the block loosening the valve seats.


#13

L

Lennie11b

ILENGINE said:
Starter problems are fairly common on the Briggs opposed twin engine. there is just so much stress on the starter, mainly because of such a small starter turning over so much mass. I have had several over the years that would be hard to start or would turn over slowly, like you describe. cleaning the brush area of the starter may help, but may also require the starter to be replaced.

Carbon buildup in the head area is also a problem with that engine. but valve clearances are usually not a problem with that engine, other than the valve seats coming out of the block. The opposed engine has some cooling issues leading to overheat of the block loosening the valve seats.
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Ok yeah yesterday I had it apart and there was a crap ton of carbon buildup on the pistons I was turning the flywheel by hand and the valves seemed to look like they where doing what they was supposed to do. So when it stops raining ill clean them pistons up what solevents is safe to use and since im new to small engines who is a good source to buy parts/gaskets from I work in a rock quarry and we shut down thru the holidays so this is my keep busy project


#14

Fish

Fish

Just scrape and use a heavy wire brush. Any mower shop will have the gaskets, and you probably need a new air filter as well.


#15

W

Woody71

I have an older Tecumseh "flatty" (L head). As you've discovered, nothing to adjust. Let me relate my experience regarding carbon on the valves and piston.

I replaced the head on my engine last spring. Broke a bolt while torquing down the new head (I won't event go into that, stupid move).

I let it sit for a couple weeks as I was out of town. When I pulled the mower out of the garage to extract the broken head bolt, all the carbon was gone! I have no idea what happened but the valves, cylinder and top of the piston were completely carbon free. I do run SeaFoam as a fuel stabilizer in all my OPE gas.

Got the broken bolt out, torqued the head correctly and it ran great all last season. I didn't lap the valves as they seemed fine.


#16

reynoldston

reynoldston

Woody71 said:
I have an older Tecumseh "flatty" (L head). As you've discovered, nothing to adjust. Let me relate my experience regarding carbon on the valves and piston.

I replaced the head on my engine last spring. Broke a bolt while torquing down the new head (I won't event go into that, stupid move).

I let it sit for a couple weeks as I was out of town. When I pulled the mower out of the garage to extract the broken head bolt, all the carbon was gone! I have no idea what happened but the valves, cylinder and top of the piston were completely carbon free. I do run SeaFoam as a fuel stabilizer in all my OPE gas.

Got the broken bolt out, torqued the head correctly and it ran great all last season. I didn't lap the valves as they seemed fine.
Click to expand...

Little men came into your garage when you were gone and cleaned it for you.


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