Briggs 16 HP I/C

[slomo]

Really think you are jumping the gun here. Set the valves proper. See what you have after. 90psi with a compression release cam, if yours has one, sounds good to me. A Briggs can run on 35psi LOL.

The engine runs fine, just down a bit on power.

Compared to what?

Are you sure you are getting full throttle? Would not surprise me that the throttle cable/linkage is set improper. Or the choke is coming on partially and you don't know it.

Betting she is all carboned up internally. Carbon chunks sitting on the back sides of the valves killing airflow into the cylinder/s. An engine this old from 1986 will be loaded with carbon cholesterol. Your engine manual probably states to de-carbon the cylinder/s say at 5 year service intervals. Bet the head/s have never been off. Could be wrong here.

Dull blades can degrade performance.

Slipping belts can degrade performance.

Dead pulleys and bearings can degrade performance.

Low tire pressure can degrade performance.

An off brand air filter can degrade performance. For that matter I've seen OEM filters act like the choke was on. Clean looking paper pleats all around. Changed the filter and she returned to full glory.

Wrong blade type with your deck can degrade performance.

 

[Rivets]

Slomo, if you had read the entire thread you would have seen that the engine is an L-head engine and it is mounted in a Simplicity tractor. The engine would have to be removed on most of these tractors to properly check clearance and will definitely need to be removed to pull and regrind valve stems. Have you ever adjusted valves on an L-head engine? I doubt it by the way your constant recommendation of always checking and adjusting valves. It takes longer to reset valves on a single cylinder L-head engine, than it takes to do both cylinders of an OHV engines, plus they take twice the mechanical expertise.

 

[StarTech]

Yes L-heads are a lot more challenging to do the valves on. And considering this is '86 model even the valve guides may be worn along with the valve faces and seats.

What worst is that the exhaust valve PN isn't listed either.

 

[slomo]

Slomo, if you had read the entire thread you would have seen that the engine is an L-head engine and it is mounted in a Simplicity tractor. The engine would have to be removed on most of these tractors to properly check clearance and will definitely need to be removed to pull and regrind valve stems. Have you ever adjusted valves on an L-head engine? I doubt it by the way your constant recommendation of always checking and adjusting valves. It takes longer to reset valves on a single cylinder L-head engine, than it takes to do both cylinders of an OHV engines, plus they take twice the mechanical expertise.

Valve arrangement makes zero difference to me Rivets. If the OP doesn't choose to keep his machine in spec that's on him. I actually learned on L-heads. They like OHV's are simple.

Listing all the negative side effects doesn't help anyone. Got to crack an egg to make an omelette.

 

[StarTech]

Valve arrangement makes zero difference to me Rivets. If the OP doesn't choose to keep his machine in spec that's on him. I actually learned on L-heads. They like OHV's are simple.

Listing all the negative side effects doesn't help anyone. Got to crack an egg to make an omelette.

The difference is a DIYer normally don't have the proper tools at hand. And it not worth the expense of a one or two time use either. Valve seat renewing tools are not cheap. Then you need the correct reamers if valve guides are being replaced. And the person doing the valve adjustment got to be extremely careful as to not over file/grind the valve stem ends or it is new valves. And this case Briggs didn't even list the exhaust valves in the IPL; although, are probably the same as for another engine in this series.

But an OHV needs an adjustment it usually as simple as removing a rocker cover, adjust the rockers, and reseal the covers. Of the engine need to be at TDC + 1/4" down Compression stroke.

I doubt the manager at O'reilly Auto Parts that I dealt with yesterday could even do that.

 

[Rivets]

Maybe it makes no difference to you, but you MUST put yourself on the DYI guys shoes when making recommendations. You may have worked on many L-head engines, but how many have you had to adjusted the valve clearance on? Back in the late 70’s I probably did more clearance adjustment on the them in a month than you have ever done. Grinding valve faces, seats, measuring, reaming and/or replacing valve guides, measuring and grinding stems were all part of the small engine repair curriculum. In this thread the OP was looking for directions as how to proceed with what he thought may be a problem. You suggest cracking the egg and looking to see if it is bad which does not make sense. I suggested to him not to crack the egg unless you have a reason to do so, to which many techs on this forum, who are smarter than me, agree with.

 

[StarTech]

Rivets, Sometimes we just have to give up on hard heads. It like that O'reilly's manager yesterday. Everytime I buy parts from them I had to jump hoops to get the sales tax deleted. Yesterday was the last straw. Not only they refused to accept my sales tax certificate they had ordered my parts under another company's name. When paid for the parts yet again they charge sales tax even with the sales tax exempt form in front of them. Three years of fighting with them was enough. I just said goodbye and that I would not be back.

Mentioning hard heads my customer is just as hard headed and he insisted on me replacing that transhift cable. This time it is going to be painful. And hopefully painful enough that he carry the PU to someone else next.

 

[Rivets]

I agree Star, but this guys head is harder than yours and mine melted together. Must be in the genes of those guys in California who are always the most “intelligent “. I’ve fought with is guy in the past and from what I’ve seen his customers are willing to pay his prices even though he charges for things that don’t need to be done. There’s one other member in California who has the same attitude. I’m glad that at my age and position I’m able to only repair the equipment I want to. I stopped charging labor and only for parts. Year round my frig and freezer stay full because things always magically appear in the shop. I don’t lock the door. Last week I finished a tractor check over, bill was $47.83 and when we came home from church found 10# of ground venison, 2# of cheese and a homemade apple pie. Life is good.
PS: I wonder if the guy has adjusted valves on a HIT N MISS engine? Bet he doesn’t know most are adjusted while the engine is running.

 

[StarTech]

Well Rivets I never seen a Hit and Miss engine myself but have heard one in the area.

I can't be that generous as there are tools, supplies, etc. that must paid for but I did just finish last year's books at zero profit. I am planning for that happen for the next three tax years too. My way of protesting. Just can't see myself supporting a government that trying to down the low income group of tax payers at every step.

I have already had to buy nearly $200 in tools already this year and that with Inside Club membership at HFT. Luckily they were on sale when I needed them.

So my main income will be the monthly SS checks.