Can I place the larger 6.75 or 7.25 engine on a 6.25 husqvarna lawnmower frame?

[patrickd5188]

Im almost certain the answer is no, bc I see a lot of mention about making sure your replacement engine has the correct crankshaft as well as other matching dimensions.

Need to replace the engine and would love to upgrade it and get more horsepower, but cant find any answer as to if this would work? I know the 7.25 is a Briggs engines so I would think the bolt pattern would match.

Also I noticed the 7.25 comes with a throttle lever, so I might have to adjust my 6.25 lawn mower frame that doesn't have one to accommodate the larger engine. I know the 7.25 has one but not sure on the 6.75 engine Husqvarna uses. Which I would gladly add/upgrade if I could increase my Hp.

If this just isn't possible, I'll try to order a matching (6.25ex) engine instead just like it has now. Saw somewhere that the 6.25 was discontinued by Husqvarna. Dang just also read that Husqvarna has begun phasing out all gas driven walk behind lawnmowers. Hopefully that wont make finding a Briggs engine anymore difficult if I do have to back with the 6.25. I've read they had alot of problems out this model (6.25ex), which i guess makes me feel better, that it maybe wasn't my fault it stopped working. But really wondering now if i even wanna go back with the same engine, if it was know known to have issues.

 

[bertsmobile1]

any engine with the same crank diameter & length will fit into the mower.
Most cranks are the same length .
So measure yours and measure the replacement you wish to use.
Usually it will be either 7/8" ( USA domestic) or 20 mm ( EU export ) .
next thing is do not be fooled by the stickers on the cover.
Check the engine model number if the old engine is 10???? and the new engine is 10???? then they are the same engine
the 10 = 10 cu inch 11=11 cu inch 12 = 12 cu in etc.
The fractional differences in Hp are generally noting more than a different main jet & governor spring or just the number printed on the decal.
No law against labeling a 7,25Hp engine as 6,5Hp but big fines for doing the opposite.

 

[patrickd5188]

Measuring my lawn mowers (6.25) crankshaft shouldn't be a problem, but I was planning to try and order the replacement engine online.
So that might make measuring difficult going off of online specs i can find. But that's a great start, and ill look into that now.

Also I believe your saying if I am indeed trying to upgrade to a 6.75 (Possibly a Honda engine so might not work) or the 7.25 (Briggs engine) I shouldn't have to worry about somebody mislabeling a larger engine (ex. 7.25) as a (ex. 6.25) ? Since I do want the larger engine, provided its a Briggs and that it will mate up for me.

Just wanna say thanks again for the help Bert, and everyone on these forums!! I know enough about these things to not be scared to try and fix something. Especially in these times where everyone, myself included, is strapped for cash. But I most often exceed the limit of what I do know lol And so ppl like yall, are a tremendious help!

 

[bertsmobile1]

You get different Hondas over there fitted with all sorts of Doo-dads on the PTO shaft so no idea about them.
The replacement engine web pages ( small Engine Warehouse & small engine suppliers ) have engine sizes or hot linke to manufactureres web pages with engine sizes on them.
With push mower engines you have a regular smorgesboard to pick from.
Generally they are all standard size unless otherwise stated.
Most of the Hondas we get here are METRIC so have 20mm PTO shafts which is not 7/8" so be carefuf.
Not sure what Honda USA puts out for the local market.

 

[Rocky J]

I replace my vertical shaft 3.75 Briggs with the Honda Clone from Harbor freight, It was the same crank shaft specs and it has several different sets of mounting holes to chose from and 2 oil fill/drains on sides and one drain under by blade . Even running at low rpm it still develops plenty of power. This will be the third year of mowing with it , no problems . Even the cable for the flywheel brake hooked up. I would go by Bore and stroke more then I would the Decal HP rating which I think they get from 4000 rpm with no air cleaner or muffler