Hey guys...
I know this update is waaaaay over due but I figured I'd post it and I do have another question. So....on the Excursion that I had an issue with the valve dropping....it was indeed a valve spring that gave way on number 9 and the valve dropped. It did indeed put a hole in the piston but the mechanic never found any pieces of the valve. He pressure tested the head to make sure there were no cracks and to make sure the head was still good. He smoothed out the rough surfaces on the head and reused it. While the engine was out...I had him put inserts in all of the spark plug holes so I would hopefully avoid any spark plugs blowing out (more on that later!) I also had him replace all of the exhaust manifold studs so they are done. Complete rebuild with the above extras was $3727 out the door. The truck has about 2000 miles on the rebuild now and I did indeed have an issue with a plug blowing out....not really blowing out....but blowing apart. The bottom half of the plug was still in the head but the inside/top part of the plug blew out. These were brand new motorcraft plugs he put in. I put a new plug in, replaced the coil as it broke, and it is good again. I got a new plug and coil pack under warranty from the parts store based on the fact that the plug blew apart. Here are some pics of the piston and the head:


My new question is this: When I asked him about which oil he would recommend as he rebuilt it....5w-20 or 5w-30 since there were 2 different specs....he said he puts Rotella 15w-40 in all of his rebuilt engines and that is was he uses in his engines. He uses is (even though it is a gas engine) he said becasue of the extra zinc and the better additive pack. I left it in but changed back to 5w-30 when I changed the oil for the first time. He swears the 15w-40 won't cause any issues or damage even though it is thicker than what was spec'd. He said I could use 5w-40 synthetic as well. Most of the miles on this Excursion are towing a concession trailer that is about 5,000 pounds. It kinda gives me the heebie-jeebies running 40 weight oil but maybe it's just me. What do ya'll think about running 40 weight diesel oil in the v-10? Either weight....being as I mostly tow with it.....dino or synthetic? Thanks for checking out the long read and your thoughts/opinions.

Jim

 

I cant believe there wasn't any damage to the cylinder wall after seeing that piston and head. The last I read about Rotella, it doesn't have the zinc content it once had. Something about the EPA and zinc. We used to run it in the air cooled Corvair engines, but the side benefit is the thicker oil took longer to leak out and burn away. I believe you are safe with 5w20 or 5w30. I would think that if the engine cant survive on that, it wasn't repaired properly.

 

Thanks for the reply. The rebuild has a 1 year unlimited mile warranty with it so hopefully....if something does surface...it'll be within a year. Being as most of the miles are towing miles....would you go with conventional or synthetic on the oil?

Jim

 

I have been using the Motorcraft synthetic blend for the last 40k miles. I recently switched to Penzoil Platinum full synthetic. I drive less miles every year now and feel better about leaving a full synthetic in there longer. Whatever you use will be fine if you change it often enough.

 

I had, at one point, used the MC synthetic blend but then started using Castrol GTX conventional (what I used in the first oil change on the rebuilt engine). I was considering going to Mobil 1 5w-30 full synthetic. I usually change the oil every 3-4000 miles. I was just thinking the Mobil 1 might offer a bit more protection.