[wrenchmen]

During the summer I noticed a few times, what I thought was some oily substance floating in the top of my radiator. There was no coolant in the oil and I thought that maybe there was some junk in the block somewhere and hoped it was not a problem.
Saturday I pulled the engine out to start my rebuild of this numbers matching block.
The coolant drained from the block perfectly clean but upon emptying the radiator it looked as if oil had mixed in,a good amount of light milky brown colored coolant drained from the radiator. next I remove the valve covers and notice some very sticky light gray colored goop around some of the tops of the head bolts, especially around both upper rear head bolts. The gray stuff was also all over the threads of these bolts.
Because these are blind holes it must have migrated past the head gaskets and up the bolt threads..everything else looked good, crank, rods, pistons, bores, bearings had very minimal discoloration with only a few rod bearings showing just a little copper.
when cleaning up the parts I found another large pile of this gray stuff in the bottom of the oil pan in the drain plug recess...it was very, very sticky and immediatley completely discolored the parts washer to a light gray!...I scraped this stuff out and placed it on a shop towel and set it on the bench and as it dried it is getting hard.
It looks like JB weld!..Has anyone ever seen stuff like this before? I was thinking maybe it was some type of sealer someone might have poured in the radiator years ago.

Also if there is oil getting in my cooling system I would think it would have to be from the block somewhere. Is there a known trouble area, or a way I can detect this myself before taking it to a machine shop?

[GoatDr]

The gray stuff is usually parafins(wax) that are contained in the oil. It separates and accumulates in the little pockets in the heads. Every old engine I've ever torn down has this. You don't get that stuff with synthetics. The stuff in the radiator is hard to pin down. It may just be coagulated rust and anti-freeze.

[wrenchmen]

The gray stuff is usually parafins(wax) that are contained in the oil.

Really!...so I might just be looking at what 39 years can do to the inside of an engine.
I have never heard of that before. At work we tear into diesel engines and they are always clean inside. I have seen black carbonized sludge but never the sticky gray stuff inside gas engines. I hope thats all it is.
Thanks GoatDr.

[mechanickeith]

Also you have to remember that some of the older oils used were non detergent. What you are describing is normal for an engine of 39 years!!!

I dont know of any way for oil to get into the radiator/coolant, unless it has an automatic trans. Then you would have atf in the coolant. There are several places that coolant can get into the oil though.

If this is an original tear down of a 39 year old engine, I wouldnt be concerned. Probably just rust/scale buildup in the radiator. Have everything hot tanked & the radiator rodded out. That should clean it all out.

[wrenchmen]

If this is an original tear down of a 39 year old engine, I wouldnt be concerned.

I hope so!.....It really does not look like a wax or parrafin substance...it is very tacky and thick.
This is what I believe is an original 124,000 mile engine. The only hard parts inside that were shot was the nylon toothed upper timing gear, all cracked and brittle and missing one tooth.
Here are some pics...

[uforacing]

Originally Posted by wrenchmen

I hope so!.....It really does not look like a wax or parrafin substance...it is very tacky and thick.
This is what I believe is an original 124,000 mile engine. The only hard parts inside that were shot was the nylon toothed upper timing gear, all cracked and brittle and missing one tooth.
Here are some pics...

Attachment 161484

Attachment 161485

Very, very, very normal.

[DiamondJim]

Originally Posted by wrenchmen

I hope so!.....It really does not look like a wax or parrafin substance...it is very tacky and thick.
This is what I believe is an original 124,000 mile engine. The only hard parts inside that were shot was the nylon toothed upper timing gear, all cracked and brittle and missing one tooth.
Here are some pics...

Attachment 161484

Attachment 161485

AKA Sludge -Jim

[SDPROMO]

I suspect that if tested, you would find that most of the dense gray material would be tetraethyl lead that had precipitated out of the fuel. You don’t find those deposits in engines that have always run on unleaded fuels. The lead not only contaminated the oil, but also formed deposits on the spark plugs; this is one of the main reasons for the vast improvement in plug life. Aviation fuel is 100LL, the LL meaning low-lead. It was blended with the absolute minimum amount of tetraethyl lead to raise the octane, and no extra due to the plug fouling and contamination tendencies. JMO Pete

[Sirrotica]

Many years ago around late 60s early 70s Quaker State refinery developed an additive packege for their oil that their engineers felt was superior to other additive packages. It turns out it wasn't and exhibited the gray gunk your engine is showing. They reformulated their oils and changed additive packages and this problem went away. I have myself seen many engines that used Quaker State that had their oil and filter changed regularly (1000) miles that when the valve covers were removed the top of the head was covered with this gray gunk just as yours is. It was always a huge amount of this gray goop, never just a small amount of it. I would ask the owner if they used Quaker State oil and 99% of the time the answer was yes. I would surmise that at some point Quaker State may have been used in that engine during that time of the additive problem. I realize any engine of the age yours is will have sludge in it, but it really looks the same as I had seen in engines using Quaker State back in that time frame.

BTW I lived in Erie Pa. just about 70 miles from Oil City Pa. , so we had many people in our area that would swear by Quaker State oil and used it religiously. None of the other oils manufactured in our area exhibited this gray goop and I was told by an former salesman of Quaker State about this problem a few years after they had switched back to a standard additive package and that solved the problem.

[gtofreek]

Seen it many times. Perfectly normal. It tends to build up in places that the oil sits stagnate. Always on old engines with lots of miles.

[wrenchmen]

BTW I lived in Erie Pa. just about 70 miles from Oil City Pa. , so we had many people in our area that would swear by Quaker State oil and used it religiously.

Sirrotica, I think you hit the Nail on the Head!...PHS shows this car was sold at a dealer in PA and from other clues I believe it has spent its life in that area.

[gtofreek]

I have torn down many engines out here in the Southwest that have had that gray goop in them. Doubt they all came from PA. I guess what I'm saying is that I doubt the location the car was sold or used in has any bearing on it.

[JJKJ]

My 76,000 mi 72 350 had this same gunk. Mainly around the upper head bolts in each corner.

[runningbwdog]

Hi,
I always thought that the grey substance was either microfine aluminum or steel/iron whose particles were too small to be caught by the filter element. This material is generated by the rubbing/friction of the moving parts in the engine.
Just my thoughts.
Mike

[PLAY400]

When we first pulled apart my 72 YC 455 the first time we pushed about 8-12"s of silver/grey crap out of the left side rear upper oil passage. So much of it that it looked to me like the back of the engine couldn't have been getting oil yet the thing sounded good when I bought it. Local Manitoba car owned and maintained by a service station owner

[BVR421]

Not using the PCV or having a clogged PCV system will encourage that grey goop to form. A lot of it is condensation, often noticed on the underside of the oil filler cap especially in the winter.

[Sirrotica]

Doubt it all you want, I know for a fact other brands of oil being used at that time frame didn't have that amount of that gray goop on top of the heads. I'm not saying other oil brands never have any of this deposit in them, just that Quaker State users had a huge amount of it. Way more than others I had seen. I worked at a chevy dealership in the area that used Quaker State exclusively and also a Pontiac dealer that used only Pennzoil and I definitely saw a pattern with the Quaker State oil of that era. I never said that it was only in that geographic area, just that that area had a lot of people that used Quaker State. Although not a scientific study I did make it a point to ask owners that I saw this buildup in their engines, what oil they used. I also made it a point to ask the salesman that I talked to that worked for them the reason why all the engines I had disassembled had all that gray goop in them. That is when I got this explanation about the additive package.

Until recently Quaker State had been the bargain brand of oil and it was sold everywhere in the world. When retailers wanted to have an oil sale that was usually the brand on sale. When Pennzoil Shell acquired them they stopped being the bargain brand because they weren't making money and they then concentrated on being quality instead of selling mostly on price. Kendall Valvoline Pennzoil and Havoline or any other major brands of oils never had this problem from what I have seen. The major players all also used the same additive package, Quaker State didn't and from what I have seen you could tell instantly which oil had that inferior additive package in it.

[mikeb]

I've seen that grey goop before. Old engine that had been run on havoline all of it's life. I agree with the person that said it had to do with moisture in the engine. Just clean it out and go.

[Ogre]

Originally Posted by JJKJ

My 76,000 mi 72 350 had this same gunk. Mainly around the upper head bolts in each corner.

Both the '72 I recently finished, and the '71 I'm working on had it in this identical area. A real mess to clean up, but no unusual wear found in the heads or the engine. Just normal old-age wear ...

Ogre

[Sun Tuned]

I believe you'll find also these occurrences in engines that were started and shut off rapidly before full operational temp was reached. Such as blocking the wifes car in and having to start yours up let her out and then repark and shut it down with only a minute or so run time. Or like my grandfather used to do when he and granny would go to the store which was .8 of a mile up the street in the 65 GTO he bought new. This car was so new my dad was the one who pulled it off the car hauler when it arrived at the dealer and then personally pdi'd the car before taking it home on his day off. EVERY and I mean EVERY 2000 miles the oil and filter were changed and only Kendall oil was ever in this car except what GM had in it when it shipped. Gramps got up there in age and quit driving so much and the car never got driven much but he really liked it, drove my dad ape. Son... there's something wrong with the car he'd say and dad would drive over and the car would run rough as hell when started and never got smoother as it warmed up. Still was around 1974-75, so leaded was still available here. Dad told him you can't drive these things a couple miles and cutem off they just get all clogged up. Fresh plug change later and was good to go. Would have to replace one side of the duals at the muffler shop cause it would rust out that pipe in about 6-8 mos. too.

Dad said the GM training center instructor said the grey stuff was from unburned condensation in residual amounts in the crankcase oil, that sit in idle places where oil is always found when engine is level and cut off, and that never gets evaporated due to short trips. Grey color was due to the additives in the gas that made it past "leaks" and the oil ratings that were used back then and it only leaves by solvent washing or serious additives over time.

Tailpipe followed the same thinking..... never got hot enough to get the moisture out.