My truck only smokes upon startup and at no other time. I feel I've ruled out everything I can and I'm left thinking it's a valve seal. Has anyone changed these before? Can it be done with the engine in the truck? Tips, tricks and techniques would be appreciated. I have a U42t 3g83 engine.
My truck's 3G81 smokes at higher RPMs and at startup. I ordered valve stem seals that I hope are correct after cross referencing 3-4 times; finally going to be doing a compression test tonight to see how likely it is that it will help. Should be able to do it with the head on, I'll write up and share part numbers once I'm successful. Here's a howto on an easy method that I'll be trying myself. Hopefully the mini Mits retainers are similar.
saga continues on trying to find parts: another order cancelled due to out of stock. I haven't checked compression yet. Still running well, just smokey. Seems to smoke much less when oil is 1/2 to 1 quart low and doesn't drop nearly as fast at that point. Keeping RPMs lower helps too. I'd say this is indicative of blowby or bad oil rings in addition to valve seals but I won't know until I test compression.
Found proper seals (same seals used across a ton of Mitsus; Mits pn Md307343 for 3g81 crosses to a felpro SS70359 - which seems to be for a v6 so I've got twice as many as I need), started installing yesterday. The type of tool in the video above doesn't work well. I got one out, but there's not enough clearance to use it for any other that #1 intake. I picked up a cheap spring compressor this morning and hope to have the job wrapped up tonight. Compression in my motor is 161-150-145. More spread than I'd like to see, and a little low on #3, but certainly not fatal in my opinion. Here's the tool I made for spark plugs. Neither of my deep well 13/16 were thin enough to get past the heat shield and have any feel for what I was doing. Same thing should work for a 3g83 hemi.
It's not pleasant to work between the rear wall of the cab and the valvetrain. Most of the work is pretty trapped in a small space, and I'm sure doing twice as many valves on a 3g83 is an extra pleasure. If I had to do the job again, I'd look at dropping the engine 4-6" for more working space, or think about getting a head gasket and just pulling the head, but that's a lot more work to just avoid some pain. I think it took me about 8 hours all told - seems embarrassingly long. If I wasn't a good wrench I'd have been totally lost so don't try it if you don't know what you can get away with tool-wise. You'll need tricks.
