Exekiel69

I will be sending My injectors to have them rebuilt and thought while I wait I could try and do the valve seals since the oil they are leaking through the exhaust is stating to annoy Me. Is it better if I turn the engine until the piston I'm working on is at the highest then compress the valve spring and remove the keeper and then replace the seal or is there a better way? Thanks.

jimbo486

I believe that's just about the easiest, safest and only way to do it. It might take some time having to rotate the engine after every other set of valves but you'll only have to turn it 3 times.

Exekiel69

I have some trouble finding TDC but I thought once the injectors are out I could put a straw down the injector hole and see how far up it goes then when it starts to return and the valve springs are fully decompressed it should be right on the spot I need it do start taking the valves apart.

I can turn the engine by turning the alternator so that wont the too hard. I was thinking once the valves are decompressed I could remove the lock clip on each rocker arm (I&E) then get full access to the valves.

Btw, since You said I will only have to turn it 3 times on what sequence do they reach TDC. This will save Me using 6 straws .

jimbo486

Have you tried using the timing pin underneath the injection pump? It locks into the pump gear which ensures TDC #1.

Being an inline motor, each cylinder has a companion. #1 and #6, #2 and #5, #3 and #4 rise and fall together. When one cylinder is firing, the other is on split overlap or TDC of the exhaust/intake stroke

Find TDC for #1 and you can replace the seals there and at #6, same for when you find TDC for #2, replace seals there and at #5, then find TDC for #3 replace those seals as well as seals at #4.

Exekiel69

Thank You, I needed that information.

Jim5870

Will he need something to hold the valve up?
Can the valve drop down out of reach?

BC847

The point of rotating the engine is to ensure the piston of a given cylinder is at TDC so that when he does remove the valve-spring keepers, the valve can not fall into the cylinder.

And if I'm not mistaken, if the piston were at BDC, the valve could possibly drop below the point you could pull it back up by hand using any exposed valve-stem. Then there's the question of could you be lucky enough to be able to rotate the engine and have the piston push the valve back up so you could grab its stem, without it potentially causing a problem. How lucky do you feel?


Folks, consider this: Once you get #1 cylinder at TDC as verified by the timing pin, make a scratch on the crankshaft damper right next to where the serpentine belt goes by the damper. Just line the mark up with the flat edge of the belt. Eye-ball it.
That way, it's SO much easier to get things back to TDC without fiddling with the timing pin.

Rick 12v CTD

And once you've found TDC for #1. just rotate the crank 1/3 of a revolution and then you got your next 2 cylinders at their tdc. Or just look for crossover, it's super easy.

mhuppertz

I'm actually surprised you are getting oil into the exhaust through the valve guides. It's a problem on gasser intakes because they are under vacuum, but our engines are under pressure most of the time intake and exhaust. If the guides are shot I could see some oil wheeping down the valve stems causing a puff on startup, but my POD's do that anyway. I could actually see wasted guides causing enough blowby up the stem to blow the seals off their seats. How do you know they are leaking oil on you?

Exekiel69

I don't know that , but I did see a thin line of oil on the down pipe (a few months ago) so I pulled the turbo thinking it was leaking and found the oil line coming from the exhaust manifold ( I actually started a thread back then asking about this) toward the front. I do not have oil consumption so I didn't think it was too extreme, and since I removed the injectors to have them rebuilt I tried to tackle it today after work but I chickened out, I don't think I'm finding TDC so I'm afraid to drop a valve and loose it. Still have the new valve seals in the box.
btw when I pulled the injectors #2 and #6 were very wet while the other injectors were dry with some carbon build up.

mhuppertz

You probably just have leaky injectors causing your oil slobber!