Extremely Confused, NEED HELP!

[Rusty Nail]

I have experienced similar trouble while runing a PCV valve in a cover with no baffle and that was my first thought. I think it's kind of common.

I am aware that does nothing to explain the difference between the trucks, but it's all i've got ATM. Unless the z-71 ends up making more engine vacuum related to the differences in the EVAP system between a '98 and a '95, then I guess it could effectively pull more oil up the PCV.

 

[gilmorec61]

I have experienced similar trouble while runing a PCV valve in a cover with no baffle and that was my first thought. I think it's kind of common.

I am aware that does nothing to explain the difference between the trucks, but it's all i've got ATM. Unless the z-71 ends up making more engine vacuum related to the differences in the EVAP system between a '98 and a '95, then I guess it could effectively pull more oil up the PCV.

I checked for the baffles, and both valve covers have the baffles.

Havent been able to do any diagnosing yet as my girlfriends dad passed away so ive been helping with that. Both of the trucks were 98s, they were essentially the same except one being 4wd. Tomorrow I will be pulling off valve covers and checking valve stem seals, as well as the drain back holes in the heads. Was doing a little more research, and some people have had the same exact problem I am because the drainback holes in the heads were clogged. I did get a chance to pull the intake off, and I opened the throttle plate, and looked into the intake and it looked like it had really slight oily film over everything, and I stuck my fingers in it and rubbed them around, and they smelled just like oil. Don't really know what that means, but throwing that out there. Also the pcv valve, and where it goes into the intake had oil on them, more than I would think is normal. Will post pics later.

After I pull the vc's, if I don't find anything I will be doing comp test.

 

[gilmorec61]

Got to take a look at everything, and it turned out that 3 of my valve seals were torn for whatever reason. They were letting in massive amounts of oil, so much as one of the plugs didnt look like a plug anymore. It actually threw my tune off, so im going to have to get it tuned again. Went ahead and replaced all 16 of them (it was a b*tch), and adjusted the valves, and it fixed the oil burning issue. It seems to have a very very slight grayish smoke, but it doesnt smell like oil at all. It smells more like fuel and it burns your nose and eyes.

Also did a compression test and was somewhat dissapointed. 6 cylinders came to 120-130 psi, and two came to 95-100psi. I did a leak down test on the two that were low, and found out that the exhaust valve seats on both of them were leaking. Truck runs fine, so im going to leave it as it is for now, as im not tearing back into the motor right this second. It only has close to 10,000 miles on a brand spanking new motor!

Thanks for your guys help!

 

[454ss]

by the sounds of it you've had problems from the start, you shouldn't burn any oil in 3000 miles after your first oil change.

 

[gilmorec61]

So after replacing those valve stem seals I thought all was well....

Then I went on a 300 mile trip right after I got them replaced, and when I finally got to my destination it was burning oil just as bad. It burns almost exactly a quart of oil every 400 miles. For the first 50 or so miles after I replaced the valve stem seals, it didn't burn anything. This leads me to believe that the people who did my heads also messed up some of my valve stem guides. Does this make sense?

Will be tearing the top end down in the next week to get heads reworked by a different company. Also replacing distributor and getting new head bolts. Any reccomendations on a replacement distributor and head bolts?

 

[heavychevy98]

I know you said they machined the heads but factory heads will only go .470ish lift before the retainers hit the seals. If they didnt machine them down or put proper springs and retainers, your cam change may have pushed you over the lift limit.

 

[gilmorec61]

I know you said they machined the heads but factory heads will only go .470ish lift before the retainers hit the seals. If they didnt machine them down or put proper springs and retainers, your cam change may have pushed you over the lift limit.

I had the valve spring seats ground down, new compcam beehive springs installed, as well as new retainers in order to clear the lift of the cam. I don't think these would be symptoms of the cam exceeding the lift limit anyways would they?

 

[gilmorec61]

So here is an UPDATE!

I went ahead and took the whole top end apart, and took the heads in to a different shop to get machined. Got a call the next day saying that the valve guides were full of SLOP and there was so much play, it was unbelievable to the manager! It wasn't in all of them, but most of them he said were bad. No doubt the amount of oil consumption was coming from the guides. After only 10,000 miles....hmmm... I think that the first shop that did my heads, didnt install the guides correctly, due to the wear.

So another $250 later, ive got another remanned set of heads, only a year later...

Will be getting them and installing them tomorrow, so it should be running better than ever.

Also went ahead and bought felpro head bolts, and the MSD dizzy, as well as all new gaskets etc.

This should fix my problem, and hopefully ill be able to enjoy my truck a little more now.

 

[98_k1500]

Sounds like you are on the right track.

 

[heavyjunk]

I HATE having to pay for sh*t twice, especially for someone else's incompetents.

Sent from my DROIDX