Valve guides

Joel · January 12, 2002

I have a 74 1/2 ton w/350 auto and the truck smokes on startup. The smoke is blue and its oil burning. There is no smoke while driving.

I heard this problem could be from warn valve guides. How hard are they to replace? Do I need to pull the valves to do this?

Joel

Kansas Kid · January 12, 2002

Depends on how mechanically inclined you are. Whats easy for me might not be that easy for someone else. I did this on my truck about a year ago and it wasn't all that hard. Parts are real cheap (valve stem seals and valve cover gaskets), and all you really have to remove is the valve covers. (and anything that prevents you from getting them off) I think it took me and my cousin about 3 hours to do this last year in about 30F weather, and that wasn't working very hard. Included drinking beer as well. LOL

I think the best thing to do would be to go buy a service manual for the truck, as it does take a few special tools, and is a little too hard for me to try and explain everything you need to do. Maybe someone else will come along an try...

95Yukon · January 13, 2002

Pull the valve covers. You need some sort of spring compressor tool and an air fitting to pressurize the cylinders to hold the valves shut. There are a few ways to do this but air is the easiest if you have it. Then compress the valve springs and remove the keepers which hold the valve springs to the valve stem. Then remove the spring and change the valve seals one at a time until they are all done. Put it all back together the way it came apart..and hopefully..no more puff of smoke.

76BBSub · January 14, 2002

Depending on how much time/money you have you may want to consider getting a valve job. That's what I did on my '76 Suburban. With the heads off you can check the condition of the cylinders and camshaft. If you pull the heads, take the extra step and remove the timing cover and check your chain and gears. I didn't do this last year, and just spent the whole weekend replacing the timing set, when it would have taken me an extra hour or two had I done it when I did the valve job.

But, doing it in the truck is pretty inexpensive and quick.

Jeff