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Hello,
I have a briggs 441777
Type 0283 E1

Wouldn't crank .. and barely with the plugs out.. so I got a battery.
Then it would crank with plugs out but hang up on the compression stroke..
So I assumed the compression release broke..
Took it apart and it looks like it doesn't have one.. I've never seen that before however I've only taken about a few briggs motors..
So does this not have a mechanical release?? If so, is it just an exaggerated lobe ?
If so I'd assume that the valve adjustment is critical and is probably the problem??

From the pictures of the camshaft that I find it does show an ACR.

Yep, it's similar to the Intek single cam.

Scrubcadet10 said:

Yep, it's similar to the Intek single cam. View attachment 66893View attachment 66893

Click to expand...

that is interesting..
i couldnt see it however i did not take out the cam..
there are definitely no parts in the bottom of the case but i suppose its possible that the
acr is stuck closed ?

the other thing is, i think the replacement cam does have the ACR.. so maybe it did not have one from the factory"?
I read some posts that indicated that the factory cam had exaggerated lobes to hold the valve open a bit longer to relieve compression

It depends if he has the 790562 cam or the newer 797242 cam. The older cam did not have an ACR but the new one does. If replacing the camshaft you should be getting the new 797242 camshaft.

The older 790562 camshaft looks like this.

StarTech said:

It depends if he has the 790562 cam or the newer 797242 cam. The older cam did not have an ACR but the new one does. If replacing the camshaft you should be getting the new 797242 camshaft.

The older 790562 camshaft looks like this.
View attachment 66894

Click to expand...

yup.. it looks like the older cam.
so maybe the valves are too loose.. might just get the updated cam

anyone know where i can get the bolt torque specs for this motor?

The only to these specs is the sump torque has been increases to 325 in / lbs. per the latest gasket kit. Of course that does fix my current gasket blow out problem. Hunting for cause now.

Sump bolt torque is 325 in/lb. Be aware that the new OEM sump gasket also comes with new bolts, and you will need to chase the sump bolt holes in the block to remove any old thread lock prior to assembly with new gasket and bolts

Well of course the cam shaft for all B&S V twins have compression release. The original Intek series used the age old Intake valve cam lobe grind where the Intake valve is held slightly open well into the compression stroke relieving compression.
Walt Conner

Did not see where you tried to adjust the valves lash to minimum specs BEFORE you took it apart? (especially the intake valves)

You certainly should not have taken the engine apart before you check the easier things first.
A lot of these Briggs v-twins do not have a compression release finger like the singles do.

The first thing you do on any of these is check the valve adjustment because normally you'll find it's two to three times wider than it's supposed to be and that's why you have no compression release.

On the singles with the finger on the camshaft for the acr, you can just tighten them up to zero lash and turn them over by hand and watch the intake valve bump open after it closes. That let you know the ACR is working. If you have one and you set the last to zero like that and it does not bump at all then you know the ACR is busted and it really needs a camshaft.

Forest#2 said:

Did not see where you tried to adjust the valves lash to minimum specs BEFORE you took it apart? (especially the intake valves)

Click to expand...

ended up putting in a new cam with the compression release..
runs like a champ now..
one very odd thing though, the valves coming out of adj, or the cam wearing a bit ( this mower is old )
over time will increase the compression.. my friend said it was getting harder and harder to start.
when i put it all back together.. it sounded great cranking over, but wouldnt start.
I checked spark and it was good.. has awesome compression. sprayed carb clean in the carb and nothing.
my buddy noticed sparks under the flywheel cover when it was cranking..
i found the starter was really loose and it was obviously causing a flaky ground which is why it was sparking. so i tightened up the mounting bracket bolts and then it fired right up.. very odd, the starter bracket should have had no effect on starting. maybe just coincidence..

The bad connection at the starter would have cause it to turn slower particularly when the resistance to turning was the highest
So you get a bigger decompression than B & S intended so not enough fuel to support a combustion

bertsmobile1 said:

The bad connection at the starter would have cause it to turn slower particularly when the resistance to turning was the highest
So you get a bigger decompression than B & S intended so not enough fuel to support a combustion

Click to expand...

it was still turning over fine.. new battery.. and even better than before with the compression release cam.
its very odd..
im thinking it was coincidence.

TobyU said:

You certainly should not have taken the engine apart before you check the easier things first.
A lot of these Briggs v-twins do not have a compression release finger like the singles do.

The first thing you do on any of these is check the valve adjustment because normally you'll find it's two to three times wider than it's supposed to be and that's why you have no compression release.

On the singles with the finger on the camshaft for the acr, you can just tighten them up to zero lash and turn them over by hand and watch the intake valve bump open after it closes. That let you know the ACR is working. If you have one and you set the last to zero like that and it does not bump at all then you know the ACR is busted and it really needs a camshaft.

Click to expand...

good to know.. I dont fix these for a living, ive fixed a few motors with failed ACR and obviously the symptom is
like a very weak battery.. take the plugs out and it cranks fine. so I assumed it was a broken ACR.
this was the 1st time i came across a motor with no mechanical ACR..
so thanks for the info.. next time ill check the lash 1st.. that said, i think this cam was worn.