Oil treatments and rodbearings

[excidere]

I recently got my '90 running well enough (and without vacuum leaks) that I am considering driving it for a while over the summer and I have a few maintenance questions. Keep in mind this car has been mostly sitting since 2001.

1) I have a light blue smoke on start up that stops once the vehicle has been running for a bit. I take this to be the valve stem seals; upon my searching I have seen a few posts mentioning AutoRX and the like. I am wondering who has used it, and if it did provide real results.

2) I have a light knock on cold start but no oil light. The knock disappears once the car has warmed up... so rod bearings will be changed before the impending 60k. Should I replace the bearings and fill it with oil and AutoRX? Or drive on the new rod bearings for a bit before using something like that?

Thanks a lot!

 

[mavericksav]

I think if it's rod you'll be able to machine your crank. but it could be valves need to be regulated. You can't just put new bearings on knocking rod!!

 

[rubydist]

if its a light knock only on start-up, chances are that the journals are not yet damaged. however, confirming this will be critical to the success of your rod bearing change. if there is any scratching or roughness that you can feel scraping your fingernail across the journal, then the crank will need to be turned and undersized bearings installed.

I would start with 'high mileage' oil and skip the AutoRx for the first fill. if its just hard valve stem seals, then conditioners like AutoRx can save them, but in the engines I have taken apart typically at least some of the exhaust valve stem seals are actually broken, and in that case replacement is obviously required.

 

[SHOtimer]

I agree with Rubydist, plus the highmileage will help prevent some of your impending oil leaks that are going to start happening on those seals that haven't been used in 10 years.

I'd get those rod bearings changed.

The autorx won't hurt new rod bearings. I'd get new rod bearings in there and then run the autorx after the first oil change with the new bearings.

I'm finishing my first cleaning cycle of autorx in my wife's taurus (3.0 ohv Vulcan), I didn't have any blue smoke, but it used about a quart of oil every oil change (typical for that motor).

We will see how it does after the rinse.

Doug

 

[mgreen1872]

As for the blue smoke, (I realize my experience may not be typical) but I had my heads rebuilt completely less than 300 miles ago and had blue smoke on startup before and surprisingly after the rebuilt heads, rings, bearings and many other things completed while it was down. Furthermore, I had a light coating of oil inside my intake and rubber intake tube.... I pulled the crankcase hose off the TB (one from valve cover to TB) and capped the TB port and took it for a drive, let it sit over night and fired it up the next morning.. NO SMOKE. I then pulled the bottom crankcase hose off of the bottom of the TB and ran a piece of wire down it, I pulled out some nasty looking carbon/sludge junk... took my air hose and lightly tried to blow air into the hose and sure enough it was completely blocked. Pulled the intake, cleaned the CCV hoses and passages using some carb cleaner and then changed the oil, long story short the smoke was due to Crankcase pressure forcing oil out of the hose from the valve cover into the intake due to the blockage of the opposite hose and after sitting the oil ran down and pooled until start up the next morning.... Case solved!


As for additives, I have never used the Autorx and never really trusted any additives, but last week I bought a 92 Dakota with a very loud tapping noise, thinking it was time for bearings/crank I poured two quarts of Marvels in it and let it run for a while in the driveway to clean before I took it apart, cut it off and let it sit until I was ready the following week... when that day came I fired it up to move into the garage and it purred like a kitten, no noise at all! As a matter of fact, it ran so nice and quiet we just drove it from Cohutta GA to Panama city and back, thing runs like a top. Apparently it cleans well like is stated....

Good luck!

 

[itwonder]

Change rod bearings
Use conventional high-mileage oil
Auto-Rx is a useless waste of money IMO.

 

[JRA2000TL]

I changed out my bearings (which weren't making noise), and used Castrol 5W-30 and a bottle of the Auto-RX. In the process of putting my 3k on it and will change the oil again. I'm going to monitor my oil consumption to see how the AutoRX does. Some like it, some hate it. I think it has some value potentially.

 

[SHOtimer]

Auto-Rx is a useless waste of money IMO.

I am in the process of seeing if it works or not....

Did you use it and have a crappy experience?

Doug

 

[excidere]

Thanks everyone! The hose that mgreen mentioned is clear. It should be noted when I checked the hose yesterday the knock wasn't there on start up but there was a good sized puff of smoke. The knock slowly came back as it idled (still very light: I cannot hear it inside the car, or with the hood shut). There's still no flickering oil light, and I'm still not driving it. So I guess I'll give the rod bearings a change and run some high mileage oil through it and hope for the best. Maybe I'll do the valve stem seals when I get to the top 60k.

 

[mgreen1872]

Thanks everyone! The hose that mgreen mentioned is clear. It should be noted when I checked the hose yesterday the knock wasn't there on start up but there was a good sized puff of smoke. The knock slowly came back as it idled (still very light: I cannot hear it inside the car, or with the hood shut). There's still no flickering oil light, and I'm still not driving it. So I guess I'll give the rod bearings a change and run some high mileage oil through it and hope for the best. Maybe I'll do the valve stem seals when I get to the top 60k.

did you check the hose UNDER the TB going to the valley of the block? Is there oil inside the intake? how about in the rubber intake hose? Pull the hose off of the manifold (the one that runs from the front valve cover up) and plug the port on the manifold and let it run or drive it for a while (long enough to burn any oil left in the intake) let it sit and see if it smokes on startup (with the hose still off of course).... as for the rod bearings having just completed it, I have to admit that it is not too bad....

 

[excidere]

did you check the hose UNDER the TB going to the valley of the block? Is there oil inside the intake? how about in the rubber intake hose? Pull the hose off of the manifold (the one that runs from the front valve cover up) and plug the port on the manifold and let it run or drive it for a while (long enough to burn any oil left in the intake) let it sit and see if it smokes on startup (with the hose still off of course).... as for the rod bearings having just completed it, I have to admit that it is not too bad....

I did; I've been replacing all of my vacuum hoses as I check them. I'll try pulling the hose and see if it makes any difference.

The last time I had the intake off I had a light coating of oil in some places in the inside.

 

[SHOhopefull]

Change those bearings NOW! No kiddin, don't do what I did. I was able to save the crank, but not by much, and it took a LOT of polishing. After the meet I'll post the pics for ya.

 

[SHOZ123]

I've used AutoRX with great success. If you have a lot of miles on the engine it will clean the rings and restore your compression and fuel mileage. It takes about 10k miles but it is just normal driving. My car went from using a quart every 500 miles to none in 3500 miles.

I also had a rod knock on the same car. The usual symptoms of knocking after a highway run and coming to idle. It turned out to be a broken bearing. Slapped in a new set of standard bearings and all was well.

 

[JRA2000TL]

I've used AutoRX with great success. If you have a lot of miles on the engine it will clean the rings and restore your compression and fuel mileage. It takes about 10k miles but it is just normal driving. My car went from using a quart every 500 miles to none in 3500 miles.

I also had a rod knock on the same car. The usual symptoms of knocking after a highway run and coming to idle. It turned out to be a broken bearing. Slapped in a new set of standard bearings and all was well.

Glad to know this. I just posted on FB about how I put in rod bearings 3k ago, then refilled with Castrol 10w30 and a bottle of AutoRX. In 3k miles of driving, I've added 3-4 qts of oil. I put almost 1k of that 3k on it this past weekend with a drive to and from Nashville. 2 qts were added about 750 miles into that trip (should have just taken 1.5 qts as it was a little overfilled with 2). I have a couple of drops from an oil pan leak here and there.

Now that it's due for an oil change, I'll put in another 5 qts of Castrol 10w30 for the "rinse" phase of the AutoRX. Just haven't seen any improvement over this 3k interval, but if it takes at least through the rinse phase + more miles, then that makes sense.

 

[SHOZ123]

I would add a second bottle and go 5k miles with a filter change at 2500 next. Then the rinse phase.

 

[ItsAnAdventure]

Hey Paul, what is the best source for the AutoRX? I know you posted it in the past but I lost track of some of my notes.......Thanks.

 

[SHOZ123]

http://www.auto-rx.com/

It's the only place as far as I know.