Rust on the cams - how to clean/repair?

[jamin]

Hi All,
I recently purchased a 3TGTE that has not been started for years. When removing the rocker cover I found rust on the cams (as shown in pics) and on the timing cog and chain.
I would like advice on how best remove this rust. I would prefer not to remove the cams.
Cheers, Ben.
[img]0511190037.jpg[/img]
[img]0511190038.jpg[/img]

[Toobs]

Theres not that much on there, some Inox and fine (300+ grit) sandpaper will take care of it.
The rest will wear off pretty quickly once you start the engine.

[Starfire]

Many cams are surface hardened and all used ones have been work hardened by use. The major part of running in an engine is conditioning the cams.

I would be very wary of using a 300 grit on the cams. I would suggest that if you want to sand them at all (running the engine will remove that surface rust in fairly short order) use something like a 1500 grit and only take off the loose top coating of rust.

As that engine has not been run for some time I would suggest that you take the time to smother the cams in moly assembly lube to protect them to a degree until the engine can supply a decent oil supply.

Once you do start running it a lot of built up crap will be knocked off of the engine and end up in the oil. If the cams look like that then there is a good chance that the rods, bores, crank and other parts do too. Do an oil change before you run it and again after 500km or so.

You may want to pull off the water pump to see what the cooling system looks like too. Again I would suggest flushing it after it has been run for a bit.

Cheers,

Terry.

[wilbo666]

A cloth soaked with oil and some rubbing would prbly also take most of it off (and when the engine is run it will take care of the rest). Also I'd be smothering the thing in oil, oil down the bores (leave the plugs out) and smothering the cam's with oil too, then I'd turn it over by hand. . I wouldn't be surprised if most of that rust disappeared after turning it over a few dozen times and rubbing the cams with an oil soaked rag.

Cheers
Wilbo

[myne]

I'd pour fresh oil in the head and turn it over for a couple of mins without the coil connected.
A decent speaker magnet to the bottom of the sump ought to protect the oil pump from anything big.
Then inspect, then drain oil. Use some diesel instead of oil, and crank it over for a bit.
Then remove the magnet and drain, Flush the sump with a few more L of diesel, and then put clean oil in.

(engines can run with diesel as a lube for short periods under low loads without issue so dont be scared)

[o_man_ra23]

id spray CRC or WD40 or Nulon Nulube down the bores BEFORE cranking at all... as this will free up the rings if they have bonded at all to the bores, and stop them from tearing bits off. Leave the stuff in there for a good half hour before turning the crank, and be generous with it. First movement should be a turn by hand. Also, any sanding you do on the cams while thier in the head will result in grit in your head which can cause premeture wear in things like your buckets.

Cheers, Owen

[Celica RA45]

petrol and a scourer ,the 1s your mums uses to wash up the dishes with

[MWP]

I would use oil and steel-wool.

Steel-wool will take off the surface rust, but not any of the cam steel like sand-paper would.

[4DaDrift]

Edited post.

[takai]

hydrocloric acid will strip corrosion from most metals yet as with everything in life
test it first and be sure that you use the right saftey gear and get a second opinion and research into it first

Uh, Hydrochloric Acid will also eat away at the metal. It is highly corrosive and will eat away at your hands too.
Not sensible.

Just use a scotchbrite pad (the technical term for what CelicaRA45 is talking about) and a bit of oil. And as the others have said smother the thing with moly lube before starting,

[river]

Hi,

Try some Coke. According to another thread it does just about everything else.

But if it was my cam, I'd use steel wool with WD40 and get off the surface stuff. Also, I'm with the WD40 in the cylinders before you hand crank it.

seeyuzz
river

[4DaDrift]

Edited post.

[jamin]

Thanks for that.
There seems to be a few options, SteelWool/ScotchbritePad + Oil, 1500 WetDry + Kero, WD40 + CourseRag, but noone mentioned MetalPolish/Toothpaste.

When I first got the motor (6 months ago) the crank was turned to test for a sieze. It turned. Things were tight. After removing the cam cover i was shocked to see the rust. It gives rise to "Is there rust anywhere else?" (like the bores etc).

Currently the turbo and cam cover are stripped off. My intention is to strip off the EFI and other piping to leave just the block and main internals. Then do an 'internals check' with a view to repairing surface rust on the cams, timing chain, and possible the boar etc etc etc.

Looks as though the block should really be stripped enough such that complete consideration can be given to all the 'metal-on-metal' components. I wasnt going to take the head off but it looks as though it would be the wise thing to do to allow full inspection of boars.

Cleanliness seems inportant as some grip may be left behind if not extremely careful. Washing/flushing the head/block/journals etc is something that now will be done to ensure everything is clean, slipery and ready to go. Water pump etc will be inspected.

Will update with pics when i get started onto this. I feel as though a simple 'cleanup the cams' thread will now turn into a 'how to rejuvinate an engine after it has been in hibernation for many years'.

[RWDboy]

If there is only rust on the cams, then I'd use some moly grease or even 'engine honey' and crank the thing over by hand a fair few times. Inspect it. Make sure there is still plenty of lube on it, then crank it over on the starter for a bit. Basically any rust on the tip of the lobe *should* wear down quite quickly - if you are worried about losing some of the 'hardness' then i hate to say it but you already have (once there is some rust there).

Unless your oil filter doesn't do it's job you shouldn't need a magnet on the bottom of the sump, but if your engine is full of corrosion etc you will want to change the oil filter, and the oil (use non-synthetic) - within 100km or so of running as the filter will be used up quite quickly.

[Mr DOHC]

a wire buffing wheel, thats what we use at work