Intake manifold gasket replacement

[lrg]

I am getting some (minor but annoying) oil leakage around the intake manifold on my '87 300dt and am about to replace the gasket. The leaking is around a couple of the runners where they attach to the head and appears to be the nice jet black goo that is coming from the EGR crossover pipe. It looks pretty straightforward and I did a quick search and found nothing special to be careful about. Is this as easy as it looks or am I missing something here? Also, I don't see any reference to a gasket on the crossover pipe to manifold joint. Should I use some sealant there? Any advice from those who have done this before would be very much appreciated. Thanks.

[sixto]

I'm not familiar with the OM603, but there shouldn't be so much oil in the intake manifold that it leaks past the gasket. Are you sure the oil isn't dripping down from a bad valve cover gasket?

Sixto
91 300SE
81 300SD

[lrg]

It seems dry all the way around the valve cover gasket. I've carefully cleaned this all up and the oil is slowly oozing out around the intake manifold gasket. It's not much volume but it is definitely leaking. This is a turbo so I think the boost pressure is helping it work its way out. I know from past experience you do get a fair amount of oil vapor in from the EGR which normally burns up. After a while the inside of the crossover pipe and intake get pretty coated so this is what I think is leaking out.

[sixto]

LRG,

If you email me directly at tabijan@yahoo.com, I have some information that might be of interest to you.

Sixto
91 300SE
81 300SD

[loubapache]

lrg:

The leak you mentioned is very typical on the OM603.XXx motor. Is it somewhere around the 1st and 2nd intake vales?

It is not a big deal but if you want a bone dry engine, replace the gasket. Once you have the thing off, you might consider

1. clean the intake manifold
2. replace the glow plugs (only $8 a piece)
3. replace the shut-off value (also not expensive).

[lrg]

Loubeapache,
Leaks are exactly where you describe. I will definitely clean out the manifold. As to the rest of the items, those sound like good ideas, I just have to wrestle with the classic Diesel owner cheapness vs. common sense of saving later work. Thanks for the advice.

LRG

[loubapache]

lrg:

In that case, you can tryn this:

1. Clean that area really well.
2. Buy a can of the liquid rubber product.
3. Spray around that.

It will stop the leak for at least a year. If it come back, repeat.

[Billybob]

I happen to have these parts laying around so if you want you can take a look. The green circular part is the Seal Ring that is used between the EGR mount pipe and the crossover pipe, and the rectangular gasket with the red sealant is the Intake Gasket used between the crossover pipe and the intake manifold. The prices are for my local dealership. The intake manifold gasket itself is around $10 - 12 here from Fastlane, I think.

I just started taking this system of my 603 and there is a 3-5 mm of "tar" coating inside the crossover and it looks like slightly less throughout the intake manifold. The closer to the EGR the more cooked it appears. If anyone has any useful tips on what solvent can be used to remove these deposits please don't be shy!

[lrg]

Thanks Billybob. I have the manifold gasket already (bought @ Fastlane for $8.46.) I'll need to get the other two. For some reason I don't currently have the flat gasket on the crossover pipe which explains why it's leaking there too. When I've removed the carbon before on the crossover I've had luck with carefully scraping with a screwdriver and putty knife then cleaning the remainder with paint prep solvent. The solvent is meant to be used on metal and cut grease so I figured it was the simplest solution. Just watch the fumes, it doesn't do your lungs any good.

[loubapache]

Billybob:

Carberator (sp?) cleaner wonders wonders on that tar.

[lrg]

Thanks guys for all your help. I replaced the intake and crossover gaskets this weekend and everything seems tight and dry. I was amazed though at how much carbon goo had built up on the intakes. I spent hours scraping and cleaning as much of it off as I could. Unlike gas engines where the fuel mixture running in the intakes helps keep all that clean, I realize there is nothing on a diesel to help clean this out. I guess I either disconnect the EGR or plan on doing this cleaning job once in a while. Thanks again for your help.

lrg

[loubapache]

lrg:

Do you have to remove a lot of other tings (fuel lines, throttle linkage, etc) to take the intake manifold off?

Any other tips I am about to do the same this summer.

I cleaned the cross-over pipe last year and I remembered it was a hassle to get the flat gasket in place while putting the cross-over pipe back.