Head gasket bad?

[XGamer223]

So, lately my Tecumseh Vantage 35 (not sure if it's this one - I swapped the engine a few years ago, used to be a BVS143, and the new one was a direct fit, it is 100% the same as my old one, just a bit newer) started losing power after 10-20 minutes of mowing. It simply doesn't take gas, it doesn't take the load at all like it used to do when it's colder, also I noticed that it perfoms overall much worse... I mean there's not much to expect from it, but it was a lot better, it bogs down on the smallest grass.

Anyways, I cleaned the carb out, opened the cylinder head, cleaned it from carbon deposits (and there were really a lot since it burns oil too), cleaned the valves, they seem to be closing properly. So, I noticed that the head gasket has stick to both the block and the cover of the head - now I'm confused if I should replace it, since it may be leaking or something.

So, after running it for a while, it starts bogging down really badly, without and with load, also starts very very hard afterwards when it stops eventaully - won't also take the throttle. Any increase in throttle results in the engine bogging down and then recovering after a few seconds. Also noticed a horrendous ammount of crankcase ventilation smoke when it boggs down.

My first guess were one of the two valves not opening/closing enough, but none of the have a lot of play when closed (both to but a really really tiny ammount). But, mostly the engine would shut down when of the valves would get stuck, and mine runs but badly.

The cylinder could use some honing, there's one really fine scratch, or even multiple but not that bad, on the cylinder wall.
I attached a few images regarding the head gasket and the pieces that stuck on the cover and block.

Here's a video preview of the issue. Don't mind the rod knock - it's a Tecumseh x)
Thanks anyone in advance!

 

[mikebarber]

The style of head gasket you have should not be reused especially in the shape that it came apart That style is NOT intended to be reused

What kind of valve clearance do you have ? I don't have the books to look it up for you in nor am I going to spend my time looking it up on the internet for you LOOK IT UP Off the top of my head I would think someplace in the .006" neighborhood as I said LOOK IT UP

New head gasket and proper valve clearances should make quite an improvement DO NOT OVERTORQUE HEAD BOLTS Gary

 

[Rivets]

First, any time you remove the head on a Tecumseh engine you must replace the head gasket. Second, when you have the head off set the piston at TDC and take your thumb, push down hard on the valve head and try to turn it in either direction. If you can move it, either the valve clearance is too tight or you have a carbon build up between the valve face and seat.

 

[mikebarber]

back when I was a kid (tires just started to have air in them ) A lot of small engines had head gaskets with a compressable core between 2 metal sides and were reusable in a pinch people reused them often and they held up I always tried to replace them but if not available the old one went back and if properly and evenly torqued they held up fine ALWAYS is such a very big word

 

[keakar]

View attachment 51899
look into this more, it looks like your exhaust valve isnt fully closed

sometimes the valve guide work loose and move making the valve no longer close

as for the rest, you cant reuse a head gasket EVER

a bad head gasket can and often does cause an engine to burn oil

to test if the valves are sealing, lay head flat with gasket side down after you pour gasoline into the port and watch if it leaks out

if the valves are sealing nothing will leak through and it will stay dry, if gas leaks through you need to relap the valves so it seals properly (youtube has videos showing you how)

 

[mikebarber]

Well I see there is so much knowledge here mine is not needed last post

 

[bertsmobile1]

Well I see there is so much knowledge here mine is not needed last post

Back when you were a boy, he copper sheeting on the copper asbestos composite gaskets , with out without a steel fire ring was thicker than a heavy duty condom .
Now days they are thinner.
Asbestos is no longer able to be used and the new pretend asbestos not only takes up a perminent shape when compressed , also crumbles .
Solid copper can be annealed and reused if not too badly deformed . The paper steel paper gaskets can be reused if the paper comes off clean as can the copper steel copper & aluminium paper gaskets
However these graphite coated paper gaskets can not be reused, particularly when large lumps have broken off .
I have seen people coat them wih silicon & shove them back in again , then again people do all sorts of stupid things to try and cut corners and save $ 6 on a gasket.

 

[keakar]

Well I see there is so much knowledge here mine is not needed last post

sometimes i feel that way too, things i learned over years and years of tinkering on things are so often non applicable to the newer designed engines