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TR6 Oil Sludge in Valve Cover - Normal?

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alexisrexx

alexisrexx

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Hi all, I'm still working through a light engine rebuild and had the valve/rocker cover off yesterday. I noticed there was a lot of sludge collected at one end of the engine. My first though is that this engine has just sat for 20+ years and it's probably just old oil. But wanted to gut-check here with the experts in case it was something to look out for as a potential issue.
 

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Good question I just pulled the head off TR 6 today on a motor that has sat for as many years maybe 20 years also. it was not like yours much cleaner for sure. There was no history of the motor but was quite rich with carbon on plugs and piston head.
At first look at your head I would say there was a lack of enough oil to the rear of the rockers. Slug should have been more even as the oil should all drain down the galley to the pan.
Fact: One- 6 cyl motor will be hotter to the rear of the block as yours shows. Two- Oil to the top of the block and or head is slow as oil pressure gets oil moving. TEST take the oil filler cap off the cover and start a motor from cold and see how long it takes until you see oil coming from rockers that hole on the top of the rocker. Three - when you complete your work add a line to the top of the head. NOTE At the rear of the head is a bolt the allows a line to be added from the oil pump area.
Slug build-up comes from lack of oil changes as oil breaks down, the additives in motor oil act as cleaning DETGERNT OIL to filter
When motors sit for a long time either inside or out oil will go away and leave parts dry you may not have rust but lube the as you expose parts. I would guess your rocker shaft may be quite worn and need be replaced and a few rockers also. Check for the amount of wear.
I removed the studs and used wood wedges to raised head until we lifted it off. It will be tight to free up.

Take your time it will all come apart with some WD 40 Hope that helps add pic as you go.
Madflyer
 
You know 'that screw' is missing from the rear pedestal ?

alexisrexx said:
all, I'm still working through a light engine rebuild and had the valve/rocker cover off yesterday. I noticed there was a lot of sludge collected at one end of the engine. My first though is that this engine has just sat for 20+ years and it's probably just old oil. But wanted to gut-check here with the experts in case it was something to look out for as a potential issue.
Click to expand...
 
Madflyer said:
Good question I just pulled the head off TR 6 today on a motor that has sat for as many years maybe 20 years also. it was not like yours much cleaner for sure. There was no history of the motor but was quite rich with carbon on plugs and piston head.
At first look at your head I would say there was a lack of enough oil to the rear of the rockers. Slug should have been more even as the oil should all drain down the galley to the pan.
Fact: One- 6 cyl motor will be hotter to the rear of the block as yours shows. Two- Oil to the top of the block and or head is slow as oil pressure gets oil moving. TEST take the oil filler cap off the cover and start a motor from cold and see how long it takes until you see oil coming from rockers that hole on the top of the rocker. Three - when you complete your work add a line to the top of the head. NOTE At the rear of the head is a bolt the allows a line to be added from the oil pump area.
Slug build-up comes from lack of oil changes as oil breaks down, the additives in motor oil act as cleaning DETGERNT OIL to filter
When motors sit for a long time either inside or out oil will go away and leave parts dry you may not have rust but lube the as you expose parts. I would guess your rocker shaft may be quite worn and need be replaced and a few rockers also. Check for the amount of wear.
I removed the studs and used wood wedges to raised head until we lifted it off. It will be tight to free up.

Take your time it will all come apart with some WD 40 Hope that helps add pic as you go.
Madflyer
Click to expand...
Hmm I had noticed that some of the rockers seemed a little loose. I didn’t know what was acceptable play but was going to check later. Thanks for the heads up.

And I noticed that bolt at the end and wondered what it was for! That could be a great idea to run some more oil up there!
 
Thanks there is a kit for the line I may have a pic of mine. Remember you only have less than 2 gal. of water in the system and your oil does a lot for cooling also. When you get it back ask about todays oils, weight, additives and such. Note oil and tires what will keep your car on the road never go cheap
 
Rocker shaft .5607 to .5612

Rockers .563 to .564 new
So a clearance of .003 plus new
Rockers are not with bushings so not more than .005 should be OK with add oil line But a new shaft is recommended
 
Sludge like that happens when old mineral oil is run for short distances without letting the engine come up to temperature. I have seen the valve cover completely packed with sludge like that. Synthetic oil does not turn to sludge like that, but it will get a milky consistency if the engine is never run at operating temperature.
 
Are your plans to start the motor? If so, drain the old oil out leave the drain plug out and pour a couple of quarts of oil over the rocker assembly then let tall hat oil drain out. Next put the drain plug back in and fill to the mark with oil. Undo the coil so the car does not start and crank the engine to get oil pressure. Then hook the coil up and see what it sounds like. Oh put that screw back into the shaft and maybe look around with a flash light to see if the screw logged somewhere by a pushrod or wherever.
 
poolboy said:
It keeps the rocker shaft itself from rotating...If the shaft rotated the oil ports will not line up with the rocker arms...plus if 'that screw' is missing oil will gush out of the hole.
Click to expand...
Oh! Wow that’s good to know! It’ll check if it’s rotated!
 
CJD said:
Sludge like that happens when old mineral oil is run for short distances without letting the engine come up to temperature. I have seen the valve cover completely packed with sludge like that. Synthetic oil does not turn to sludge like that, but it will get a milky consistency if the engine is never run at operating temperature.
Click to expand...
Ah ok! I haven’t worked with older mineral oil since I was a kid, that’s good to know, thank you.
 
sp53 said:
Are your plans to start the motor? If so, drain the old oil out leave the drain plug out and pour a couple of quarts of oil over the rocker assembly then let tall hat oil drain out. Next put the drain plug back in and fill to the mark with oil. Undo the coil so the car does not start and crank the engine to get oil pressure. Then hook the coil up and see what it sounds like. Oh put that screw back into the shaft and maybe look around with a flash light to see if the screw logged somewhere by a pushrod or wherever.
Click to expand...
That’sa great idea. Yes I’m be starting the engine hopefully by the end of the summer. I’m assuming it needs to be similar mineral oil in order to break it down properly?
 
In the old days I had a 1958 GMC pick-up I drained the oil ( a six cyl ) replaced it with kerosene and ran the motor for a short time got oil press. and then drained sump that cleaned quite a bit of the motor and head. Kerosene has some lube in it, I did not drive it just idle for about 5 min. Today there may be stuff that can do the same Seafoam is one it can be added to gas to clean carbs and oil to free up gunk. Try that for a few oil changes. Read more about Seafoam( any auto parts )
 
Most likely the rocker arms and shaft are unusable if the engine has been run without the screw in the rear pedestal. Also, it seems like most peoples experience with the auxiliary oil line has not been positive and diverts oil from the lower engine. Apply the money not spent on the oil line to replacing the shaft and replacing or re bushing the rocker arms.
Berry
 
titanic has a point if shaft and rockers are worn less oil as pressure can be lowered. Remember to check and if needed replace pressure relief pin and spring. Reason is oil pump is positive pressure and the relief opens at about 100 psi. mine was worn and stuck open and zero pressure at idle, and the spring can brake also. It is that brass cap near the oil pump outside the block . It is above the oil level and can be check at any time when cold. The oil line is an option
 
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