B and S MST

[bertsmobile1]

The actual numerical value of the head bolts is nowhere near as critical as you are thinking it is
What is critical is they are all the same so there is no weak spot for the gasket to blow at .
The variation will depend upon things like old or new bolts and wet or dry threads .
Also some L heads are iron barrels with iron heads while others are alloy for both and some are iron barrels with alloy heads.
Then there is the gasket material when it changed so did the head bolt torque
Because the compression ratio is quite low in all side valve engines they do not need to be all that tight
Unless you have done a lot of porting & extensive head work you are restricted to around 7:1 max and most B & S engines barely make 6:1
Because the numbers are in inch pounds , not the usual foot pounds the torque range seem huge
Divide by 12 to make it ft lbs the you are looking at approx 11.5 to 18.5 or 15 +/- 4

Unless you are using military / areospace certified tooling, most deflecting bar torque wrenches are marked in 5 ft lb incriments so the implied accuracy is 2.5 ft lbs ( 1/2 the graduations )
Vernier style torque wrenches all use springs so they will rarely be accurate to within 10% regardless of the fact they have divisions as low as 0.5 ft lb on the scale .

back in the day when your engine was made it was finger tight ( fully seated ) then 2 x 1/4 turns for coarse threads or 3 x 1/4 turns for fine threads.

 

[Hammermechanicman]

Back in the 5hp briggs go cart days people thought we helicoiled the aluminum blocks for strength because of so much compression. Bert is right. L head engines might make 8:1 on a good day with engine mods. We did it because we took the heads off a lot to clean, check guide slop and lap valves often. We would reuse the old style head gaskets a half dozen times.

 

[Mark 2020]

Thanks everyone for the awesome responses. How do you come up with the model series number from the engine number(14D932-0110)? I come up with a 140000 series 223cc which doesn't show on any of these charts.

 

[ILENGINE]

Good deal, does the dealer model lookup site show more than just the operators manual on the Briggs site?

Mark the dealer site allows us to look up common specs using the full model, type, and code, and in some cases we can input the actual engine serial number. We get bore and stroke, replacement engine if available, common torque specs, service manual, parts diagrams, owners manual, common part numbers, crankshaft part number and dimension, length, and diameter. That is what is listed under model search. We also have access to service manuals, service and parts bulletins, and dealer training. But some of the information that we have access to is proprietary and cannot be shared with the general public.

 

[ILENGINE]

Thanks everyone for the awesome responses. How do you come up with the model series number from the engine number(14D932-0110)? I come up with a 140000 series 223cc which doesn't show on any of these charts.

That engine would be considered a 140000 series but those charted are not completely updated and have missing information and incorrect information if things have been updated.

 

[Mark 2020]

Thanks for clarifying that, I thought I was just missing something simple. You guys are all great at your craft and I appreciate y'alls willingness to help the far less experienced.

 

[StarTech]

Briggs has been quite lazy about keeping service manuals and other documents up to date. This why having Power Portal and experience is beneficial. It is also why we need model, spec (type) numbers, and even sometimes the date code of the engines so we can research them. So far in just the last year Briggs only released one new service manual and it covers the 12V300 series Vanguard engine and they have never updated any of the older service manuals. At least they got someone updating the Power Portal better than in the past.

This not updating info can be a problem when we give current info vs what is out there on the web.

Now (with) the OP engine info we can see it is an OHV engine instead of a L-head engine which requires a different SM.

 

[Mark 2020]

When I initially googled the B&S head bolt torque chart that's when I saw the example from mymowerparts.com that was so detailed and was wondering if that was available to the masses on all types of motors. The L head was a response to a guys question on another Q&A. I really appreciate everybody's prompt responses. Happy Holidays

 

[ILENGINE]

Mark there was a period that the chart that was supplied to the dealers would be several years old, with old data that may of been updated to a different torque. Or new engines that would come out that wasn't on the chart. We would have to look for the APSI or advanced product service information to get the specs and torques for engines that wasn't included on the chart or the service manuals.

And if worse case scenarios would have to contact dealer tech support and they would have to contact the factory to get the information that we needed.

 

[Coleevans321]

I saw a link in a response for head bolt torque that was extremely in depth(170 page MST manual on L heads), is that material available to anybody? Or is that a paid for platform?

I am b&s mst. New to the sight. I can access all files. Let me know model type and code and I can find out anything you need to know