Flushing high mile motors?

[jesterb]

A few club members and I just finished a valve adjustment on my 3FE with 215K on it. When the valve cover was removed we saw an abundance of sludge/carbon on the rocker arms and inside the valve cover. One of the guys suggested changing the oil and running marine clean for about 500 miles. Then changing again. There were a few different opinions in my garage so I figured it would be a good subject for debate. What does everyone think about flushing motors with high miles?

 

[cahilc]

jesterb,

The trick is to flush it slowly. If you bust to much crap loose, especailly with sludgy motors it can clog a main bearing oil path.

Can you say ... " full motor rebuild" ???

I'd recommend diesel motor oil because it contains a higher ratio of detergents. It will clean slowly over many oil changes.

Harsh solvents in the "do-it-quick" cleaners will also turn your gaskets to puddy.

Can you say ... "Mucho oil leaks" ??? But then again this might also be a feature. You would never have to drain your oil ... just replace the filter and keep topping it off.

Just my 0.02 cents,

Cahil

 

[cahilc]

One last thought ...

What oil you use doesn't really matter compared to the fact of oil pressure which everyone seems to be missing.

Synthetic oil vs. conventional oil ... blah, blah, blah ...

Use the correct viscosity oil to maintain correct oil pressure for your motor.

This begets the question ... "What's the correct oil pressure for our motors ?"

Cheers,
Cahil

 

[mpetersrx7]

I have heard you can add a quart of ATF to your oil for about a tank of gas (~300 miles) right before you change your oil will help clean out the gunk. Have never done it though.

Mark

 

[Benji]

I agree with cahlic: Don't do a quick flush with harsh detergents cause your gonna get oil leak central. Your driveway will look like an oil field.

I use 1 qt. Rislone oil additive http://www.rislone.com/engine.htm each oil change and this seems to clear up the build up, while not effecting the seals and gaskets (works gradually). If it is running fine, I would not bother with the quick and dirty method. It's better to have the stuff tied up instead of free floating in your engine.

You could add about 12 oz. of Berryman's B-12 and run the engine for a few minutes and drain the oil. It would be diluted enough to prolly not hurt the gaskets. I would not run it long though. What ever you use, make sure to change your filter often so there is new filter space available for catching foreign crud.

Don't know the exact oil pressure, but I usually try to stay right in the middle of the gauge.

Congrats on the valve adjustment.

 

[cahilc]

Don't know the exact oil pressure, but I usually try to stay right in the middle of the gauge.

I'm *always* on-or-above the top two thirds guage mark at highway speeds.

How about U ???

Cahil

P.S. Mobil One 15w-50 me use.

 

[jesterb]

Congrats on the valve adjustment.

Thanks, Benji. Euclid was the main man on that project. Just put a wrench in his hand and he is a maniac . Then its all for me, j/k. I'd be willing to try the diesel oil route. Honestly though, the truck runs fine. Sounds like a sewing machine(with a flowmaster and no cats) post valve adjustment. Just sux to know the crud is there.

 

[jesterb]

Valvo max life 20w-50 here. I'm at the same oil pressure level as Cahilc.

 

[cahilc]

Just re-checked my oil pressure to be sure.

Engine cold ...

@ 550 rpm 60% on the guage

@ 2000 rpm 70% on the guage

Cheers,
Cahil

 

[jhstatts]

Should I be worried that my oil pressure gauge is always pointing at the top notch? Sometimes a little below, sometimes a little above.

I am changing the oil tomorrow, FWIW.

 

[Man Jerk]

Other than using the stock gauge, how can you go about checking oil pressure. I've always (3 years) run at about the 1/3 mark on the stock gauge, and am curious if that is accurate or not.

 

[jhstatts]

majanrk... I guess that is my question as well.

 

[roscoFJ73]

Other than using the stock gauge, how can you go about checking oil pressure. I've always (3 years) run at about the 1/3 mark on the stock gauge, and am curious if that is accurate or not.

You can hire/buy an oil pressure gauge with a flexible hose and adapter that plugs in to the engine block where your oil sensor fits.
There is a series of tests involving running the engine at various speeds.
Easy to do with one on the throttle and another watching the gauge.

 

[cahilc]

jhstatts,

My guage duplicates what you said. The top mark, about 2/3'rds up the guage. Just below at idle, sometimes dead on and if engine cold and on highway just a little above. As teh engine warms up a bit at highway, either dead on the top mark or just below.

I don't know what the correct pressure should be. I don't know how to accurately check the pressure. I'm real curious to find out !!!

What I do know is that correct pressure is the goal. Oil weight/viscosity should be used to adjust pressure to the correct level. The fact that I'm running synthetic Mobil One 15w-50 with high pressure tickles me pink. I couldn't be happier. If anybody changes to synthetics they should monitor their pressure.

Cahil

 

[cahilc]

One more thought ...

Rule of thumb is 10 psi per 1,000 rpm.

Cahil

 

[roscoFJ73]

A few club members and I just finished a valve adjustment on my 3FE with 215K on it. When the valve cover was removed we saw an abundance of sludge/carbon on the rocker arms and inside the valve cover. One of the guys suggested changing the oil and running marine clean for about 500 miles. Then changing again. There were a few different opinions in my garage so I figured it would be a good subject for debate. What does everyone think about flushing motors with high miles?

My personal thoughts are not to touch it unless you are prepared for a rebuild.
Your getting different opinons because sometimes it works and sometimes it dont and you wont really know until its too late.
You should be ok if the compression is good on all cylinders.
I did a flush once on a V8 and the cylinder with slightly lower compression got serious compression leak and had to be rebuilt.

 

[euclid]

I recomend using Sea Foam to clean it out. I ran a bottle of it through my motor just before the last valve adjustment. I used it to clean injectors by sucking it into the motor through the vacume supply on the booster, then pour some into the crank case for 500 miles before an oil change. I also add a V8 size can of Restore into each oil change.

GT

 

[jhstatts]

Cahil... well, that is nice to know. I just got worried since it hardly ever changes. I am running Shell Rotella 15W40 (don't know if that is a good thing or a bad thing). The wagon seems to like it.

 

[cahilc]

running Shell Rotella 15W40 (don't know if that is a good thing or a bad thing). The wagon seems to like it.

Jason,

Sounds like a perfect thing. 15w-40 is my favorite fern oil for normal motors. Monitor the oil pressure and adjust oil viscosity accordingly in the future, say 100k miles from now.

:+)

Cahil

P.S. Ummm, stay away from carb cleaners for a while ... please ...

 

[Man Jerk]

So if I'm running 10w-30 and am registering a bit low on the oil pressure, should I try a 10W-40?