Should Rear Main Seal Been Replaced At Time of Engine Rebuild?

What car ?

 

When you say "completed and engine rebuild" - that can mean many things. A broken timing belt typically won't require a bottom end rebuild and therefore the crank shaft is not touched.

If what I just said fits your situation, no need to be replacing a main seal without reason.

 

A truly "rebuilt" engine should have had the rear main seal replaced, no question about that. If it's leaking it's due to improper installation. To me, any leak, for any reason, this soon after the overhaul is the builders responsibility.

 

Not true.
What car is this?
A 348 or 355 top end rebuild where you don' t touch the bottom end does not require the gear box to come out, and therefore no rear main seal is replaced.
So, what car ?

 

I agree if just a top end job but my post was referring to a so-called rebuild.

 

OP has a long thread about misaligned bores in a 348 spider so I guess its that car

 

If leaking, it needs to be replaced. It's not the shops fault, just bad timing.

 

During a rebuild?

In my opinion, uh, yeah. Kinda stupid not to.

 

Having spent 30+ years with a 308 I can say that it wasn't until my 2010 major that I had an oil leak free car. As others have said, if it was just a top end rebuild then the seal would not have been addressed. However, a leaking rear main seal is not big deal if it's just an occasional drip on the garage floor provided you monitor the oil level, and it is not contaminating other parts such as the clutch disk (unlikely on a 348/355). It's more of a nuisance than anything. However, if you track the car you may not be allowed on the track with a leak.

Personally, I would monitor the leak and see how bad it is. If it's minor I wouldn't bother to address it, unless it becomes severe, until the next major. Probably not the popular, "It's a Ferrari. Everything needs to be perfect." point of view. But just go to any mall and look at the parking places. They are all covered with drips from seal leaks and you don't see a lot of broken down cars on the road due to them. Think of it this way. If the door of your house falls off in the middle of winter you probably replace immediately it due to excessive heat loss. But if there is just a small tear in the weather stripping you will probably wait until a convenient time to repair it.

 

Get your car back. Drive it. Enjoy it. Monitor the situation. It's not like if you don't fix it now you can fix it later. If you feel uncomfortable doing that ask them if it need to be addressed immediately.

 

I would be extremely disappointed with the mechanic and repair facility. I most likely would not let them work on my car again. To me it means that they assigned the work to someone who didn't give a spit about telling the office or lead mechanic that this unit is also leaking here. Could be the kind of place where everything is assigned to jr mechanics and the lead tech is only called upon when the jr tech says they need help. Some places when you ask for help too often the boss deems you incompetent or a PITA and you get replaced so you can see how that can end up being your problem. Looks like no one checked over the jr mechanics shoulder until the thing was all put back together and now..."Oh look, there is a leak there too!" Does not work for me.

It's like those dentist offices where the doctor has pushed down most of the responsibility and accountability to the hygienist and assistants and sometimes you may not even see them during a visit! It says to me that the place isn't being run correctly.

 

I'd like to point out that the rear seal on the 348 is not the same as the earlier or post 355 models. The gearbox mates to the engine in a unique way. If the crank seal leaks it will leak into the gearbox, if the mounting flange is leaking then gearbox oil can find it's way out, and finally the rear main seal flange can leak oil as well, point is, there are 3 seals back there. And if they took then engine out and gearbox off then they are dumbass's for not replacing those seals and gaskets.

 

When you said engine rebuild I thought it was an engine on the stand, torn down to the bare block, pistons, rings, bearings, etcetera type of rebuild. If it was just pulling the heads then no they shouldn't have done the rear main. With the 355/348 just because the engine is out of the car doesn't mean the transmission was removed. I thought it was on an engine stand COMPLETELY torn down.

Having said that I have changed the rear main seal on my f119d twice, the first time with the engine still in my 348. The transmission gets removed giving access to the rear main seal.

 

+1 They were doing the top end not a full engine so i dont see you have a comeback

 

If I'm not mistaken I think the OP mentioned they removed the engine... Curious if they split the gearbox, if they did then yeah they should have addressed the seal. I'm also curious as to how they know it's the rear main seal.. if it leaks it'll leak into the gearbox.

 

I would have had somethings looked at as the engine was removed. Should not have been very expensive to have the clutch and associated parts looked at and determine what you want to do with that info.

 

In order to inspect the rear main seal, you have to remove the transmission from the engine, and by then you might as well replace the rear main seal. This is not the fault of the dealer. Old main seals leak from Lexus to Porsche and Ferrari. You want it fixed, simply pay for it.

 

The rear main seal should be replaced every time the gearbox is off the engine.

That's what I do every time.

 

I'm just a bystander here, but I have the same question.

If an engine rear main seal leaks into the gearbox, how do they know it's leaking?

If they did separate the engine and gearbox then the seals should have been replaced, no question.

 

Haven't had issues with the rear main seal on my F-car, but on other cars I've seen that the oil leak will quickly manifest itself by leaking between the engine and gearbox: there is enough of a gap.

 

The 348 & 355 are not like other engine & gearbox mates. The clutch and flywheel sit at the rear not between the two, the crankshaft is splined and the input shaft runs all the way thru the gearbox to the other end, due to this the crankseal between the engine and gearbox can not leak out to daylight. The plate that the seal mounts in can leak, though not common, or the o ring seal could but that would be gearbox oil.

This unique mount is why I question the shops assessment, esp if the unmounted the gearbox. Personally if I was pulling cylinder heads then I'd also spilt the gearbox, otherwise it's a half ass job and begging for issues later.