M116 Oil Consumption

[JamesDean]

Hey everyone,

A few weeks ago I repaired the oil level sender seal on my 89 420SEL. Which, I thought, was a major contributor to the oil consumption problem I was having. Its got about 215k miles on it now.

It appears to be using about 1 quart every 1500 miles. I do think it could use valve stem seals being replaced but I've never done anything like that so I don't really know where to begin or to just send it out to my mechanic to replace them... Anyone know how much that would cost?

Here's some of the engine related work according to my documentation:

214k = Replace Cam Oiler Clips
208k = Replace Timing Chain and Guide Rails
150k = Replace Left Cam Shaft and Rockers
137k = Replace Timing Chain, Timing Chain Cover Seal, Right Bank Headgasket

At 215k, I would think maybe its due for some head work?

As usual I appreciate your comments and thoughts.

[pawoSD]

If none has been done before its definately due for head-work. Valve guides and seals at the least. Seals cost me $400 at the dealer on our M103, so on the M116 maybe $650 for seals? If it needs guides....easily double that most likely.

Our M103 was using a quart every 600-700 miles before the seals were changed, now its less than 1 qt in 5000 miles. My M116 has no leaks and was rebuilt 40k ago....uses/loses 0 oil period.

[JamesDean]

Originally Posted by pawoSD

If none has been done before its definately due for head-work. Valve guides and seals at the least. Seals cost me $400 at the dealer on our M103, so on the M116 maybe $650 for seals? If it needs guides....easily double that most likely.

Our M103 was using a quart every 600-700 miles before the seals were changed, now its less than 1 qt in 5000 miles. My M116 has no leaks and was rebuilt 40k ago....uses/loses 0 oil period.

To my knowledge it has not seen any head work. So yeah, its probably due for guides and seal. It will probably need more than just guides and seals though I'm sure. Its never just one thing lol.

This faint ticking noise in the one head has me worried. It used to be louder until I changed the oil and replaced that pickup in the pan. I had the valve covers off when I replaced the cam oiler plastic bits. I checked the lobes they all looked OK, no obvious damage. It might need hydraulic lifters. My old 2.6 did. That was $600 or so I think.

[pawoSD]

My M116 makes a ticking at idle to about 1400rpm when warmed up.....but when I did the cam oiler pieces it had no marks or wear on the cams either. Probably lifters in my case also.....but I don't want to do it right now.

[JamesDean]

Yep. First and foremost is guide rod mounts, before my new tires get all funky. Then maybe valve job...

[rickjordan]

What weight oil are you using? Before tearing back into the engine, possibly running thicker oil may slow the rate of consumption Also, is the oil consumption rate a sudden increase from before?

[JamesDean]

Currently running Rotella T6 15w40.

Not sure how this compares to the past as there was an oil leak at the oil level sender inthe pan...