Hobby Horse 2 #1 Posted June 11, 2013 I'm re entering this as a new post to see if anyone responds. I had a lot of responses to my original post and wasn't sure how to continue. Sorry if this is not the proper way to do it. I have an Onan 416 with no compression on the back cylinder. I removed the head and the exhaust valve would spin when fully closed. I removed the valve and was able to easily remove the valve seat insert with my fingers. I guess that from being loose it was beat down by the valve. Does anyone know what, if any options I have from here.Thanks for any help that you can give. Share this post Link to post Share on other sites
decksetter 50 #2 Posted June 11, 2013 Yep, I fixed my brother's 20 that was like that. Runs like a champ now. Valves spin like that when they are adjusted out of spec and the adjuster is hitting the cap holding the valve open instead of having the .005 gap the intake valve likes. As for the seat, the one I did this to was still in place but loose, so it hadn't torn anything up yet. Hope yours is to. With the valve in place and the sorting holding it tight to the seat, take a center punch and punch the block around the seat in 4 places. 12, 6, 3, then 9 o'clock. Basically you're just going to dimple the engine block so it holds the valve seat tighter. Sent from my DROID RAZR using Tapatalk 4 Beta Share this post Link to post Share on other sites
Hobby Horse 2 #3 Posted June 12, 2013 Thanks for the great advice decksetter. I don't think that the seat insert was damaged, just loose. I'm going to do as you suggested and see how it turns out. Share this post Link to post Share on other sites
