Originally Posted by redhawk
I apologize everyone as in my header for this post I meant to say weldment cracks not firewall cracks. The weldments on the earlier RV4s are a weak point in the aircraft and I am looking at buying one that actually has cracked weldments and was looking for owners with experience at replacing these.
You are good... me and Charlie got side tracked... My bad....
So if you are not a builder there is time to kearn.
That thread I linked to was pretty good start. Search these forums for more threads. There are threads going back over 10 years. You might reach out to those members.
It is kind of a big job. I "supervised" my hanger neighbor do this. You are going to take the engine and mount off (someone may have different opinion). You have to support the plane. It is a matter of unbolting and drilling out rivets. Removing the weldment and installing new ones (back drilling to match existing holes). There is a lot of fiddling and possible shimming. Do you have drawings and builders manual? You can get RV-4 drawings and manual on USB drive if you are registered owner from Vans for not too much money. Someone on the fourm might have manual and drawings to loan you.
Many people upgrade their engine mount and gear at this time. However that is more expense and time, with new brake lines, fairings... etc.... However the longer gear helps prop clearance and landing/takeoff angle of attack... Looks better to.
I would put out feelers on these forums (classified) and call Van's for hired hands if it comes to that. Good luck.