Auto-Rx, dump early?

Status
Not open for further replies.
O

otis24

Joined
Oct 30, 2005
Messages
1,995
Location
South Dakota
1991 Chevrolet K1500 with 4.3 V6 has blue smoke on startup. I'm sure it is the valve stem seals. Engine has 87k miles and was a short-tripper (28k miles in 20 years by the school where I am employed). I purchased it in March and average 500 miles per month. The smoke seems to have gotten worse with Auto-Rx. I'm about 1500 miles into the Auto-Rx treatment. The oil was last changed by the school a year ago, but only had 1k miles on the OCI when I purchased it. I'm wondering if things will get better after the rinse phase.
I'm tempted to go ahead and change the oil now and add Mobil Super HM or PYB. The truck will see more mileage during warmer weather than it will in the winter. I would like to get to the rinse phase before winter and hope a HM oil may have some effect on reconditioning the seals.
 
I have seen people get good results from using HM oil when seals have gone hard.
But realistically, how much oil are you using?
Unless you are having to top up frequently, you may as well just stay the course for the full oci before changing.
 
Originally Posted By: otis24
I would like to get to the rinse phase before winter and hope a HM oil may have some effect on reconditioning the seals.

Rinse phase, its not a laundry machine. LOL Don't hold your breath, get that out and just fill with QS defy and hope for the best, it may work.
 
Originally Posted By: otis24
1991 Chevrolet K1500 with 4.3 V6 has blue smoke on start
up. I'm sure it is the valve stem seals.


If the seals are the same as in my gen 1 SBC, they are just little o rings that break the stream of oil on the stem allowing some to drip away and not travel all the way to the guide. These o rings harden then fall off and end up in the pan. There is nothing left to condition.

Forget the stop leak I recommended above. The only way is to run thicker oil or thicken the oil with an additive.
 
Auto-Rx takes time to work. If you're suddenly in a hurry have a mechanic check your engine and do the valve seals if they need it. It can be done without removing the heads.

Even if the problem is too far gone the Auto-Rx will still do some good cleaning out the engine. It might even help by freeing up the oil control rings just below the compression rings.

If you have the time let Auto-Rx do what it can do. If not go see a mechanic.
 
Cars didn't even used to have valve stem seals. Nothing wrong with a little lube.
 
Originally Posted By: zach1900
Nothing wrong with a little lube.

Nothing other than increased pollution, the smell, poisoned catalytic converters, the annoyance of the blue smoke...
 
Valve seals are super easy on this engine. Let the Auto-RX do its thing, if it still smokes then just put new seals in.
 
Originally Posted By: Eddie
Follow the Auto-RX plan to get the best results. This from my personal experience. Ed


Agreed, and 1500 miles is the recommended interval so yes, time to change to the rinse phase.
 
I thought 3000 miles was the interval. I think it recommends changing the filter at 1500 mile into the rinse phase, if you have heavy sludge.
I get two new tires tomorrow, and a spare tire. Longer trips will then be a possibility.
 
Originally Posted By: turtlevette
Originally Posted By: otis24
1991 Chevrolet K1500 with 4.3 V6 has blue smoke on start
up. I'm sure it is the valve stem seals.


If the seals are the same as in my gen 1 SBC, they are just little o rings that break the stream of oil on the stem allowing some to drip away and not travel all the way to the guide. These o rings harden then fall off and end up in the pan. There is nothing left to condition.

Forget the stop leak I recommended above. The only way is to run thicker oil or thicken the oil with an additive.



When valve stem seals are toast they harden, crack and fall off into a few pieces. Either live with it or replace. HM oil is not going to help here.

The amount of oil one uses when there is blue smoke at start-up is not really noticeable.

Continue with the Auto-Rx plan.
 
Just curious as to why the smoking would get seemingly worse. Looking down the fill hole, all I can see is some heavy varnish. When I replaced the PCV valve a couple of months ago, it seemed sticky and a little gunk on the back side. Perhaps the Auto-Rx is cleaning some unseen sludge and the flow rate of the oil is improving?
 
Originally Posted By: Donald

Continue with the Auto-Rx plan.


Since he plans to dump the Auto-Rx early, I wholeheartedly agree! Most people on this site get something cleaned with this stuff, but according to their posts, it's not their engine.
 
I replaced valve stem seals eons ago on a 4.3 V6.
They were shot.
The nice thing about old Chevy pushrod engines is they are easy to work on.
You need an an air compressor and spark plug inlet to hold the valves in place. You also need a valve spring compressor tool bar.

116l1mc.jpg
 
Originally Posted By: otis24
Just curious as to why the smoking would get seemingly worse. Looking down the fill hole, all I can see is some heavy varnish. When I replaced the PCV valve a couple of months ago, it seemed sticky and a little gunk on the back side. Perhaps the Auto-Rx is cleaning some unseen sludge and the flow rate of the oil is improving?


Don't not make any decisions about your engine condition by looking down the fill hole. Pull the valve cover.
 
Don't need the air compressor or the spark plug air adapter, just feed a bunch of nylon rope into the spark plug hole and turn the engine over by hand until it binds. This way you don't have to worry about the valves rocketing into the cylinder if you bump them.
 
Status
Not open for further replies.

Similar threads

E
Which HM oil for swelling rubber seals?
Replies
17
Views
2K
hrv
M
Kreen with Auto-RX/HPL Engine Cleaner
Replies
18
Views
3K
Retirednow
O
  • Locked
Heavier oil?
2
Replies
23
Views
4K
otis24
O
Replaced the valve stem seals.
Replies
6
Views
2K
otis24
O
Bad valve guides?
2
Replies
32
Views
6K
otis24
Back
Top