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I replaced the head gasket and nothing changed. It was running but getting harder to start than wouldn't do it at all.
There doesn't seem to be any gasket between the cylinder head and base. So what does that leave? I cleaned the valve seats and top of piston. There is no scoring in the cylinder. This motor is on a tiller.

Are these motors only supposed to last a couple of years?

Thanks for any advice.

Lets starts with a model type and code off of the engine so we can see what you are looking at. 20 psi is very low, there is suppose to be a gasket between the head and the block. Most are a graphite type material, but the older ones where metal.

Not going to run with 20 PSI compression.

Your compression tester may be inaccurate. Make sure it is for small engines and not for cars.

primerbulb120 said:

Your compression tester may be inaccurate. Make sure it is for small engines and not for cars.

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What is different? I have two compression testers and have used them for many years on anything with a gas engine from a scooter to a large truck and they have always told me what I wanted to know. Not that I am arguing here just curious? because you must have a reason.

I have a Harbor Freight car compression tester that gives me inaccurate (low) compression readings on small engines. I figured that the tester needs the larger displacement of a car engine to work correctly. The larger the engine, the larger the compression reading. A leaf blower gets no more than 60 psi, while my 9 HP ATV gets 120 psi. It could be that my compression tester is just low quality, but I think that you should use a tester made for small engines when testing small engines if you want accurate readings.

primerbulb120 said:

I have a Harbor Freight car compression tester that gives me inaccurate (low) compression readings on small engines. I figured that the tester needs the larger displacement of a car engine to work correctly. The larger the engine, the larger the compression reading. A leaf blower gets no more than 60 psi, while my 9 HP ATV gets 120 psi. It could be that my compression tester is just low quality, but I think that you should use a tester made for small engines when testing small engines if you want accurate readings.

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First of all my tester is top of the line Snap-On. Just never looked for a different compress tester because never felt a need to. What you are saying dose make sense. but never came across a tester for small engines only compression tester, not saying there isn't such a thing because I haven't looked. I said I have two tester and the other one is just a real old antique off name tester I picked up at a flee market and both tester read the same.

I don't have the numbers with me right now.

I tried the tester in an Evinrude 8hp motor and it was about 95# so it works.

Can't remember where I got it or who made it but it is probably a cheap one.

I'll get back with you tomorrow.

ba_50 said:

I replaced the head gasket and nothing changed. It was running but getting harder to start than wouldn't do it at all.
There doesn't seem to be any gasket between the cylinder head and base. So what does that leave? I cleaned the valve seats and top of piston. There is no scoring in the cylinder. This motor is on a tiller.

Are these motors only supposed to last a couple of years?

Thanks for any advice.

Click to expand...

How did you clean the valve seats?

Engine #'s would be helpful like ILENGINE has said.
Valves fully seating?

ba_50 said:

I replaced the head gasket and nothing changed. It was running but getting harder to start than wouldn't do it at all.
There doesn't seem to be any gasket between the cylinder head and base. So what does that leave? I cleaned the valve seats and top of piston. There is no scoring in the cylinder. This motor is on a tiller.

Are these motors only supposed to last a couple of years?

Thanks for any advice.

Click to expand...

You start by saying you replaced the head gasket. Then you say there isn't a gasket under the head. That is very confusing to me? Seeing you have very low compression if the head gasket is missing you might start there. If you did replace the head gasket did you clean the head and cylinder real well? Have you got the valves adjusted right or a bent valve? Could the rings be stuck in the piston? All anybody can do here is just guess but you are the person working on the engine so you will have to look at everything till you see the problem which should be obvious when you find it.

135202
1259E1
93021 3YB

On my Stihl chain saw the cylinder head comes off and there is a gasket on the bottom. The parts diagram indicates the cylinder head doesn't come off on this Briggs. That is what I was referring to, so the head gasket is new.

I used a wire brush to clean the valves. How do I know if they need adjusting?

This thing gets a lot of use so I don't think the rings could be stuck, but it wouldn't hurt to put some transmission fluid in the cylinder.

ba_50 said:

How do I know if they need adjusting?.

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Check the valve clearances

How do I measure the clearance? I have a Briggs repair manual but are they all the same?

Sent you a pm

ba_50 said:

135202
1259E1
93021 3YB

On my Stihl chain saw the cylinder head comes off and there is a gasket on the bottom. The parts diagram indicates the cylinder head doesn't come off on this Briggs. That is what I was referring to, so the head gasket is new.

I used a wire brush to clean the valves. How do I know if they need adjusting?

This thing gets a lot of use so I don't think the rings could be stuck, but it wouldn't hurt to put some transmission fluid in the cylinder.

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A chain saw has a 2 cycle engine and nothing like a 4 cycle Briggs. I am completely confused here? I just never came across a Briggs engine that the head didn't come off. I sure would like to know more about this engine. If the head doesn't come off how do you get to the valves? I am way over my head on this one so someone who knows this engine better then I had better help you. I don't know how the valves even operate much less adjust them. Send a picture if you can. Always willing to learn something new.

ba_50 said:

135202
1259E1
93021 3YB

On my Stihl chain saw the cylinder head comes off and there is a gasket on the bottom. The parts diagram indicates the cylinder head doesn't come off on this Briggs. That is what I was referring to, so the head gasket is new.

I used a wire brush to clean the valves. How do I know if they need adjusting?

This thing gets a lot of use so I don't think the rings could be stuck, but it wouldn't hurt to put some transmission fluid in the cylinder.

Click to expand...

OK all the Briggs experts just what am I missing here?? The best I can come up with is a 135202 flat or L head engine. This 4 cycle engine made like a 2 cycle chain saw engine??? I know about the time I would say there isn't such a thing someone will prove me wrong. Just can't find anything on it. I know trough the years they have made some strange engines. Just last week my son-in-law came home with what they call a hot tube engine which runs without a spark plug. :confused2:

The bigger valve turns much more easily than the smaller one which according to utube might be letting to much compression through. It showed how to measure the valves , so that is next. I found the clearances too.

Something I do, is when the valves are closed, I put my thumb on them and push and and see if they turn. If they turn they are not closing, and are leaking. The 1352 series should be a L head with 8 or 9 bolts with 1/2 hex heads that hold the engine head on.

ILENGINE said:

Something I do, is when the valves are closed, I put my thumb on them and push and and see if they turn. If they turn they are not closing, and are leaking. The 1352 series should be a L head with 8 or 9 bolts with 1/2 hex heads that hold the engine head on.

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If the engine is the 1352 series L head just remove the valve cover ( breather cover) and check your valve stem to lifter clearance.

The intake valve wouldn't take any feeler gauge and the exhaust was .011, which is max. Does that mean the valve head is wearing so the clearance decreases? Right at the moment I don't have a valve spring compressor or jig for filing off the valve end.

ba_50 said:

The intake valve wouldn't take any feeler gauge and the exhaust was .011, which is max. Does that mean the valve head is wearing so the clearance decreases? Right at the moment I don't have a valve spring compressor or jig for filing off the valve end.

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Sound to me like you are lacking in tools. A couple of screwdrivers and a grinding wheel. Made due with what you have. Been there and done that. Just be very careful when grinding the valve stem.