firemn131

Hi Fuel level....
Car was running a very high idle for most of its 1000 miles. I found the issue and it may be part of the high fuel?
Also, I self cleaned and reworked the original fuel injectors.
No cats H pipe,
It has been mostly short trips.

I cant wait to see the next 1000 mile report.

Thanks for all of the input.

Merry Christmas.

BC

I love this. What do you have to lose? It's already broken, so use it as you choose.

firemn131

The original post was asking what other collateral damage could be expected.

FredR

John,

You are now running a 6k rpm grinding machine and nothing you can do is going to change that. With the end float you are running the coating on th epistons is likely not going to last too long and then the bores will be toast. Assuming crap is circulating throughout the engine things like the hydraulic lifters are not going to fare too well and all the plain beaings ar elikely to going to get the crap beaten out of them.

Maybe we can run a sweep to predict what is going to go pop first?

If I were you I would only run a mineral 20w50, sling some STP oil treatment in it to boost ZDDP levels and change it a bit more frequently than normal. Alternatively maybe you could also try some of that PTFE stuff if they still sell it [Slick 50?] just to see if it can cut down on the friction between the crank and the webs.

On the positive side you must be running the only 928 S4 automatic in the world with zero possibility of thrust bearing failure occurring!

Rgds

Fred

Simon928

I believe that Shell Rotella has good levels of ZDDP in it.

77tony

I think Herman K has a low mile (IIRC 21,xxx miles) S4 motor in his man cave on stand and ready to ship. Just sayin. T

BC

Anything that touches the oil with metal in it and that moves is toast.

But it already is, so why worry.

docmirror

I gave a mediation plan with the full flow filtration method. This will help, but not solve.

Mobil 1 at that weight has 1200 ZDDP PPM. While that is sufficient for our engines, in this case where we have metal being made, more is better. I prefer Castrol oils, and in this case, still add some cam guard, or ZDDP Plus.

Try running some longer trips, get your idle in spec, insure you don't have vac leaks, and I think the fuel emulsion will go down. It takes time running for the fuel to be boiled/evap out of the oil.

Red Flash

John, you've got nerve, and I like it! Very interesting results.

OFF TOPIC: My problem is that when something breaks I think I need to fix it. It's come to the point that I have all these old things that I fix and I have no time to buy anything new... :-)

ON TOPIC: I find it difficult to believe that more ZDDP would really reduce metal if it is coming form the cams.

skpyle

docmirror, stupid question: Is a bypass oil filter a 'must have' for a reasonably healthy 928 engine, or just his particular situation?

Thanks,

Seth K. Pyle

docmirror

Not a stupid question at all. I would say the lubrication system and filtration are fine without the full flow bypass deal on a normal engine. Modern lubricants, and filters are sooooooo much better than they were when the 928 was designed that we're better off than the original systems.

Of course, this engine has suffered a metal event, so it's best to segregate whatever we can from a particulate filter. Of course, you can't use one of these on a pressure system as they produce too little flow and that's why there's a bypass circuit under high oil demand.

I first used one of these filters in a late 60s VW bug which lives it's whole life without ANY kind of filter! It kept the engine cleaner, and provided long service for a non filtered system.

Normal drain interval, and normal service are fine with the standard filter. But not this engine.

skpyle

Thank you! I very much appreciate your advice.

I am still learning the game of want vs. need for my 928.
I am running Mobil 1 15W-50 with a few ounces of ZDDPlus, with a Mahle oil filter. Wasn't sure if I needed to look into the Amsoil filter.

firemn131: Ride her until she goes off the rails. Good Luck!


Seth K. Pyle

firemn131

UPDATE
1 year later.

Car has been my general daily driver (good weather, local and when I am not hunting or fishing).

About 3000 miles later. Starting to hear a consistent metal to metal sound. Initially it was just on start up after a few days of not driving. Now because my ear is in tune, I can hear it most of the time after warm up too.
Still runs cool with good idle and oil pressure.

A bit sluggish at times but still will spin the tires off when desired.

So, the end is probably near.

Was going to sell it to finance the paint job on my junk yard find 92 968. I put the motor back together and it is running great.

Wife asked me why I was going to sell it. I said to finance the 968.
To be honest, I felt a bit guilty having 2 cars that were not necessary.
Wife and I crunched some numbers and found that keeping both was not unrealistic.
I LOVE MY WIFE!!!

I found another complete engine, so the 928 resurrection will begin after Christmas,


If I had a choice, I would have done it exactly the same. I think that if I drove it conservatively (never gonna happen), I could possibly get another year out of it.

Conclusion,
If you have a TBF motor that is running, you may be able to get more time and miles out of it. Knowing that it is a one way road.

Center and lock down the crank between the fore and aft crank travel and drive on.


Recommended max wear limit is ....................0.40 mm
My engine before refresh...............................1.29 mm

I had hoped to get a year out of it.
Mission accomplished.

hlee96

Glad to hear you're keeping it. Thanks for the update!
Hoi

Harvey928

Also glad you are keeping the car. Now you have a winter project that will keep you busy