Hard starting

[slomo]

typically what is the compression of a 6.5 hp briggs engine?

Okay, is this a new fresh engine or one that's mowed more grass than many others? Neglected oil changes? Never cleaned the cooling fins? Rough guesstimate is 30-140psi. You never specified engine condition.

This engine,after priming 6 or 7 times, kinda chugs then dies a few times before it runs normally..any thoughts??

Lack of maintenance for one. Sounds like you are fair with wrenches. Is the plug oiled down? Have you ever cleaned out the fuel tank? Ever installed new fuel lines? Ever checked the valve clearance? Bet lots of no's come up here.

Its a head gasket

How did you confirm this?

and yes a briggs will run with 30psi compression, but it starts hard

Nothing new to report here. Old news to most of us. Lack of compression could make hard starts, sure.

This engine,after priming 6 or 7 times, kinda chugs then dies a few times before it runs normally

If the primer is actually working, you are flooding the cylinder. Most every primer engine out there, requires 2-3 pumps. Many have stickers that state this very thing. Nothing in the engine manual that says 6-7 pumps for starting. So you are at fault here.

I hooked air up to block and found it leaking

Again another inconclusive test. Was this air in the plug hole? Did you move the flywheel so the valves are in a closed position? Or just connect a hose and heard a leak? This tells us nothing.

Personally I dont appreciate your attitude

I would swallow a bit and realize the gentleman trying to assist you has fixed more mowers than, well most of us will ever see. Lets all chill and get your mower running.

 

[Jeff P51]

Sir it was a blown head gasket..it now has 100psi compression , very little carbon build up in combustion chamber.Yes air in spark plug hole, Piston at tdc on compression stroke when air was introduced..put soapy water all around cylinder head..looked like a friggin bubble factory.6 to 7 pumps is what I was giving it in hopes of starting it. I know 2 or 3 should be sufficient. And number of pumps didnt really matter, it was going to start hard no matter what. Confirmed head gasket blown by removing head and visually inspecting gasket. Stevie Wonder could see it was damaged. The engine is back together, starts with one to two pulls with 2 or 3 pumps . of primer bulb...I could inspect valves and clearances but I dont see any reason to do so. Fuel tank clean..it only has one fuel line which seemed brittle and o replaced that before I even tried starting it. The mower was mfg in 2011...im assuming it has cut a few lawns.. dont really know its not mine..engine oil looked fresh, air cleaner was decent, looks like someone was taking care of it. Im guessing head bolts might have loosened up which may have caused head gasket issue...breather unobstructed.....anything else u think might have missed?

 

[slomo]

Sir it was a blown head gasket..it now has 100psi compression

Great news.

Confirmed head gasket blown by removing head and visually inspecting gasket. Stevie Wonder could see it was damaged.

Fabulous.....

.I could inspect valves and clearances but I dont see any reason to do so

Sounds like it's starting fine. There is a reason to keep valves in spec. Just stating the obvious.

Im guessing head bolts might have loosened up which may have caused head gasket issue

That was my next question. Were the head bolts loose. Nice catch sir.

anything else u think might have missed?

Lapping the head and head mating surface prior to installing a new head gasket. Every one I've seen require lapping flat again. Keep the head bolts at factory spec once a year. Easy 12 second check. Some plate glass, 220, 400 and 1000 grit wet/dry paper. Let the paper do ALL THE WORK. Rotate the glass around while you are rubbing on her.

Glad to hear you got her running.