What causes the OHV's to go out of gap ?

[Sean McGillicuddy]

This problem keeps resurfacing ..
My craftsman 18.5 hp engine ( on my lawn tractor ) has me resetting the gap I think to much...Is there a trick to keep it gapped. ?

 

[saewoody]

This problem keeps resurfacing ..
My craftsman 18.5 hp engine ( on my lawn tractor ) has me resetting the gap I think to much...Is there a trick to keep it gapped. ?

How often are you needing to reset the gap?


Sent from my iPhone using Tapatalk

 

[Sean McGillicuddy]

How often are you needing to reset the gap?


Sent from my iPhone using Tapatalk

Twice to three times a year

 

[festerw]

I had the same issue with my 25hp B&S. Looking around I found that the sleeves in the head that the pushrods run through were walking out of the head. From reading it seems that any sort of debris in the cooling fins will overheat the heads and make the sleeves walk out. Easiest fix was to remove the heads, set the sleeves back where they belong and then dimple the top of the head so the sleeve can't move. Been over a year since I had to adjust them the last time.

 

[Ashful]

Easiest fix was to remove the heads, set the sleeves back where they belong and then dimple the top of the head so the sleeve can't move. Been over a year since I had to adjust them the last time.

Going only by your description, I’ve not seen this engine, I’d be thinking about running a hand reamer thru that valve guide after dimpling.

 

[festerw]

Here's what the head looks like under the valve cover with the guides where they shouldn't be. All I did was dimple the aluminum around the guide (thanks for that I, my brain wasn't working this morning and sleeve was what I came up with lol) the guide sits just low enough to dimple it without interfering with the guide itself.

 

[Highbeam]

When you're adjusting the valves 2-3x per season, are you loosening them every time or going back and forth between tightening and loosening? How do you know that they need adjusting?

 

[Sean McGillicuddy]

Hard to start flywheel , barely moves with a brand new battery ..

 

[duramaxman05]

A lot of it depends on the series of Briggs engine. Inteks are some of the worst about that. They have a poor air filter set up and allows dirt to be sucked in. I have set lots of valves due to this problem. Also the valve guide problem as well. Definitely keep the fins clean and use a sae 30w oil that is rated for small engines as they run a little warmer than liquid cooled engines.

 

[Bad LP]

I had a Honda engine on a trash pump with the same problem but it would happen weekly. Never did see anything wrong with the studs or guides. It finally died a hard death but it really didn't owe me anything after all the water it moved while digging a pond. After that it became very unhappy at a friends place who used it to suck sand and small stones in order to deepen their mooring area.

 

[Kevin Weis]

The problem is it's a Craftsman engine. Enough said.

 

[redmanlcs]

i agree on the craftsman engine.. well for me craftsman anything is crap even the ratchets with a lifetime warranty. I spend more in gas returning them than to buy a better brand. On a side note.......I have some ratchets made in Taiwan that works 10x better than craftsman ratchets.. i can only assume their engines are crap too....

I have never seen valves that needed adjustment that much. Even my old dodge slant six with solid lifters only needed adjusting once or twice every couple years.

 

[Sean McGillicuddy]

This crappman mower is the first that made me aware that the valves even had to be adjusted …. I've had a couple diff types.. now problems like this one...lesson learned ..