Banshee365

Hey guy's. I'm getting a '96 LS 400 running again after it was parked about 4 years ago due to the transmission shedding material and clogging the strainer. I'm installing a salvaged transmission but the car's timing belt was changed 100k miles and just over 10 years ago. I've got the entire front of the engine disassembled and have just reached the top of the mountain to start installing the new components.

The car had an oil leak for quite some time that made the oil pan area nasty. I thought the cam and crank seals could stand to be replaced but after getting a look at them I'm just not sure anymore.

I looking for a few more sets of eye ***** for my photos to get some more opinions on whether to change the seals or not. I know, I know, the seals are very cheap and very easy to install right now at this point. My problem is that I never changed cam or crank seals unless they are leaking. This car has 225k miles on it and I'm sure there is a groove where the seals ride. This means you cannot simply install a new seal as the groove will quickly eat it up and BINGO, you just took a non leaking seal and made it leak! The wetness under the crank seal in the photo is coolant from removing the water pump. I think the crank seal is leaking some so I may replace that. I'm afraid with the groove it will have that I'll have to install a repair sleeve which isn't very cheap.

What do you guy's think? To me it looks like the valve covers are leaking more than the cam seals.

aomdedude1

I personally don't think your camshaft are leaking at all. I think it is your valve covers. Thats a common place to have an oil leak on these cars. MAYBE the crank seal has a small slow leak, but this could also be residual leakage from the valve cover dripping down or something. Since your are there I would probably at least replace the crank seal, but those cam seals look fine.

Just torque down the valve cover bolts, see if they are loose. If so, then there you go, that's your leak probably. I can't think of any sources of oil that go higher than the valve cover.

Banshee365

Ugh, autocorrect changed 'pics' to 'picks' in the subject and I can't edit it. Oh well.

After posting I checked the valve cover bolts and all 16 were less than finger tight. Pretty crazy. I don't know how the FIPG points are with it being loose like that.

Is it common for a 200k mile engine to have a groove in the crank requiring a sleeve with a new seal? I'm a bit afraid to remove the seal for that reason.

RA40

iTrader: (6)

My suggestion would be to replace the valve cover gaskets since it is accessible. Most of the LS's by now are showing leakage. Mine were at that same barely finger tight but even after snugging them down, I still get some oil migration coming out. Less than before but still leaking.

Cam seal does look good though at 225K and if the seals were changed at the last TB service, they are potential leakers. At your discretion and typical service on the conservative side would be to change them for preventative measures.

sha4000

iTrader: (1)

I agree with RA40.

Legender

At those miles I vote valve cover gaskets for sure. Just had those fixed on mine with 203k miles.

Banshee365

Thanks for your reply. I agree it would be best to replace the gaskets to really fix the leak, along with new FIPG per the manual. I think I may forgo that at this time until I know the car is running and driving okay. I'm bringing the car back to life and with a salvaged transmission, I'm unsure how successful the resurrection will be. If it's successful I'll probably do the valve cover gaskets. It's not much harder to do them even when the engine is all back together.

I agree on the preventative replacement side of things about the seals. The last TB job was done by Toyota at 120k miles. This was the first timing belt service. The one I'm doing is the second. I don't think Toyota/Lexus does the seals unless they are leaking so I'm guessing my crank and cam seals are original. With that said, I'm nervous about changing the seals that are not currently leaking with new ones over the original groove that would then cause a leak. Unless I can be persuaded that maybe the design of the shafts or seals usually don't cause the grooving that I'm speaking of. If I knew the sealing surface of the shafts were perfectly flat and clean of grooves all 3 would already be replaced.

sha4000

iTrader: (1)

I've never heard of anyone having problems after replacing those seals. The surfaces are flat and I don't know what grooves you are talking about.

aomdedude1

So what I THINK you are saying is that you believe that the cam and crank seals themselves will wear a grove into the shafts that they are supposed to be sealing and so you think that replacing the seals will somehow cause a leak due to the "grove" that was worn in by the rubber seal?


If that is what you are saying, then no man. I have never in my life heard of that happening. The seals are made of special rubber. The rubber is a billion times softer than the metal and there is no way it would wear a grove into the sealing surface of the shaft. That just doesn't happen.


EDIT: I retract my previous statment: http://rlhudson.com/Shaft%20Seal%20B...e-cause15.html

According to that link, it DOES, in fact, happen. I was wrong!.... VERY interesting topic, but to be honest with you Banshee365, I HIGHLY doubt your shafts have any severe grooving that would cause a leak upon seal replacement. IMHO

Banshee365

Yea, it absolutely does happen. I've got a Ford small block 302 on the engine stand right now undergoing a full rebuild. The harmonic balancer has a deep groove from the front cover seal. They sell repair sleeve's to cover the groove to provide a smooth sealing surface. It's pretty common on higher mileage engines. Getting contaminants in the seal will most definitely groove the sealing surface. This is very common on pinion seals on rear ends as well. The yoke should usually be replaced or polished along with the new pinion seal or the groove will wear the new seal in very short order.

With the crankshaft being hardened, I think I will replace the front seal under the assumption that the sealing surface will be smooth.

aomdedude1

I had no idea...! I love learning new things!

It makes sense too..