Valve guide replacement?

[88K5Jimmy]

My 88 smokes on startup and has for a while and I've been told that if you replace the valve guides it can eliminate this. From what I understand you get the #1 cylinder to the top and then take out the plug and use compressed air to lift the valves, remove the rocker arms and replace the valve guides.

Can you replace all the guides at the same time or do you have to unscrew each plug and use compressed air in each cylinder? Also, what is all involved with re-adjusting the rocker arms?

Thanks

 

[mofugly13]

You dont replace the valve guides, you replace the valve stem seals. You use the umbrella type seals, not the o-ring type. You have to do one cylinder at a time with the compressed air. When I did mine, after I was done, the passenger side exhaust was really smoky after the engine warmed up. I didnt know WTF, but after a week or so it stopped. Somehow, oil got into the exhaust and it took a week to burn it all out. I don't know how that happened, but I think that the air compressor/valve holder has something ot do with it. Also, the motor was very neglected by the PO and ended up spinning a rod bearing few months later.

 

[JpEater]

I have heard some people say that they use both umbrella and o-rings to make sure that they seal good. You can just use a compression tester with the removable guage and the air pressure inside will hold the valve up. I have also used small cotton rope push a couple of feet in and rotated that cyl. up and the soft rope will hold the valve up. Watch out if you use air cause if your motor is worn the air pressure could spin it over.

 

[gmtech954]

also use all intake valve seals the exhaust ones dont work well and start leaking again. ive done this on a sh*t load of motors without problem. also i do it by bringing the cylinder to bdc so it cant spin and with the rockers off the air has nowhere to go any way

 

[1985_K5_Silverado]

I'm a big fan of the rope method, but I'm kind of a slow plodder when it comes to wrenching.

 

[NEK5]

ok....my 90 blazer smokes on startup and believe when it was warm out it smoked a little while running but no when its been 40 or below for past couple months its been hard to tell...my blazer also burns oil quick..could that have to do with the valve seals?

 

[uglychevyZZ4]

1-BEWARE OF USING AIR..., if the valve dosent seat good [ ie: A worn engine, yes over 80K is worn] the valve can drop inside that freakin sux..NO the motor wont spin over if it leaks, itll drop, and i use a soft rope and stuff in ALOT of it, then GENTLY roll the engine BY HAND over till it stops turning, dont jam it hard, then GENTLY tap the valve spring to see if it is held up, if it us, go to town, and yes use the umbrella type! I just did this 2 days ago. and dont forget to roll the engine backwards to get the rope out. if youv never removed valve spring keepers, the easiet way is use a socket and tap the top with a hammer, theyll pop out first wack

2-yes you have to do each cylinder seperatly.

3-you need to set your valve lash. you will need valve cover off clips to set them by ear....screw down til they shut up (get quiet) then go 1/4 more down... then your good.. if you dont have the clips itll be hard to identify which ones are noisy.. this is the proper way to do it.

BIGBLAZE433- yes thats what you need also. in extreme cold the oil is so thick it dosent run down the stem as bad..