Heavy oil usage after head change.
 

Here's one for the serious motorheads on the forum.

2000 WJ 4.0 204K miles with a "Clearwater" head installed at 154K miles. Engine runs strong and only has a slight seepage leak around the oil pan gasket. Rear main seal and valve cover gasket are dry. Oil drain plug is new and not leaking.

Here's the symptoms. Since the head change, it's been using a lot of oil that has gotten worse lately. I put it down to rings because of the added cylinder pressure of new valves sealing well. It used to make some white smoke that I thought was steam because of the cold at the time, but it's turned blue over the summer. It's now using a quart of oil in 700 miles. Plugs show white ash on them.

I pulled out the CCV valve and it is clear and dry with no "blowby" coming out the filler cap or valve cover vents when running with the CCV removed. I did a compression test, book says 120 to 150 is normal. Results 1 to 6 are as follows; 185,190,180,175,185,190 with around 120 on first compression stoke. This is with the throttle plate held wide open.

The smoke is constant at idle, but disappears when underway. Using engine braking when descending a hill doesn't seem to make a large amount of smoke either.

My thoughts are this, valve stem seals. The head came completely assembled and I have no idea what they used for seals. My first idea is to replace the seals without removing the head. What do you think?

What brand of seals do you recommend? I've used Perfect Circle Teflon seals on my Chevys when they first came out and you had to machine the guides to get them to fit. Now everyone makes seals that just slip on. Who makes the best, regardless of price? Do you think I'm thinking right?

Dave read your post 3 times and I would have thought the very same thing, anytime you tighten up one end the other tends to go. But the compression test shows all to be ok for a engine of that age.


My experience like yours is mostly with SBC's and the seals would be where I went to first. Doing it with the head in place makes sense and only removing if the seals don't help.


Have you called Clearwater and asked them about it to see if they may have experienced an issue like that before with the head? If not I would call then first and see.

might be worthwhile to do a leakdown test just to rule out the bottom end

I thought about that, but ruled it out because I have no vapor coming out of the valve cover while it's running with the CCV removed. The inside of the CCV hose is oily, but not dripping wet. Intake vent hose is dry.

Fred, you and me both with the SBC. Half the time when the valve covers leak and you get that burst of blue smoke on startup, it's the oil drains in the heads that need cleaning. I've changed stem seals with air pressure in the cylinders before, but watching YouTube videos has taught me a better trick. Pack the cylinder with about 10 ft of 3/16 or 1/4 nylon rope, leaving some hanging out the plug hole. Turn the engine over by hand until you bring the piston up and pack the chamber with the rope. This holds the valves from possibly dropping into the cylinder when you remove the keepers. It was always a problem making sure the piston was a TDC before applying the air or it would spin over. This makes to SO much easier and you don't need a compressor available. Of course, you should remove all the rockers first. That's not for you, but for others. You know, it would be a real beach having to remove cams to do this!

About calling Clearwater, what are they going to do, send me another set of seals? I'll get my own, thank you!

Is 1 quart ever 700 miles excessive? I only ask because I once owned a 85 Jeep Cherokee. It had the small 6 in it AMC bought from GM (3.0)? It burned a quart every 500 and the Jeep dealer told us that was within spec.

Have you tired a leak down test ?That would show you where the problem is.If its the rings it will it hissing out the ccv/dipstick or out of the valve cover.If its a valve seal it will hiss in the intake manifold if its the intake valve seats and for the exhaust same thing but out the exhaust manifold.

A leakdown test is going to prove nothing because the valves are new and compression is higher than normal for the miles. I can't begin to tell you how many cylinder leak tests I've done over my lifetime and at this point it won't prove anything I don't already know. Before the head change it was using a quart in 3000 miles which I consider normal. I'd be concerned if it didn't use any. At 5000 change intervals with semi-syn, the oil comes out clean enough so you can see thru it in a bottle so I know no combustion gasses are getting into it. The problem is now it's changing it's own oil! I actually believe there aren't any seals in it at all or they're cheap umbrellas.

I just ordered a set of Fel-Pro Viton seals so we'll see what happens.

Dave my thought on calling them was to check on the gasket used when you changed the head. With some heads I had better luck with different brands of gaskets on them, I had to use different ones with Brodix than Dart heads.


Would mean nothing if they supplied the gasket I had to call Brodix when I ran their heads using the style I had on the Darts. I know they should be the same but not always, I found out after using several hundred dollars in gaskets before calling.


Then if not another set of eyes from the people who made them.

You're good, Fred! We also checked the gasket, a Victor Reinz, against the old gasket for water passage alignments and since there's no oil passing between the block and head, I can't see an oil problem because of that. Oil drainback is good so there's no oil pooling in the head to flood the seals like on a SBC, plus ALL the plugs have white ash on them. Most of the smoke appears after long periods of idling and not on cold startup until the oil gets circulating. My main concern is it destroying my cats, those F***ers are expensive!

The weird part is I don't get a lot of smoke with engine braking! You would think with the high vacuum levels it'd be the worst then.