Greasy Gunk in Intake

[CedarGrove]

Purchased on 84 C10 this weekend. It hasn't run in a few years but the previous owner says it should be good except for a water leak near the front of the engine on the passenger side. He's thinking freeze plug. Anyway...I haven't poked at it very much yet but did remove the air cleaner today and noticed that the intake manifold is fairly well caked with a greasy soot...I'd estimate a good 1/8 of an inch thick. Is this normal for a rig with 200 thou? Anything I should check for straight away? I'm guessing removing and cleaning the manifold is in order, but I was wondering if this is a symptom of another problem?

Thanks,

Lewis

[john8662]

Congrats on the new to you truck, it will actually be a lot of fun once you get fully acquanted.

The gunk in the intake is completly normal for an EGR 6.2. The light duty 6.2's had the EGR valve that allowed exhaust gasses (sut) into the intake. The intake is already breathing oil from the CDR (Crankcase Depression Regulator, think BIG PCV), but with oil the sut sticks..

The Best upgrade is to not clean the one you have, but to upgrade to the HD series intake. This will remove the EGR function and actually lead to a cleaner burning engine, with the capacity of taking in more air and a little better performance.

Since you have an 84 with the fuel filter mounted to the firewall, I happen to have an intake that will do just what I'm talking about if you're intersted.

Welcome to the Page!

[CedarGrove]

Thank you John. That sounds like good news. I was a bit concearned when I saw that mess but feel better now. I am interested in the manifold, but right now my main interest is to hear it run. I hope to purge the old fuel and bleed the system with fresh diesel on Saturday. With any luck, we'll hear it fire up this weekend. I'll be sure and report how it turns out.

I am interested in the J intake, so send me an email and let me know. I am cars_r_coffins@yahoo.com.

[CedarGrove]

So things went well with our project this weekend. We started by replacing the lift pump...Not because we knew it was bad, but mostly because I got a good deal on one at a store that was going out of business and I was going to be purging the fuel system anyway. Previous owner told me it had a new fuel filter so I let that ride for now. Anyway...Long story short. Filled the radiator and the block was leaking like crazy from 2 freeze plugs even before we fired it up. Put a couple of fresh batteries in. Replaced the ground from the block to the cab. Manually jumped the glow plugs at the relay, gave it a shot of WD-40, and fired it up. The engine sounded great. No white smoke to speak of. We only ran the engine for about 1 minute. We are feeling pretty good about this pig in a polk.

Problems we've identified so far...

1) Freeze plugs. Previous owner says he had the really hard ones behind the engine replaced a few years ago. We'll need to do the other ones below each injector. The one on the drivers side at the rear of the engine and the one on the passenger side at the front of the engine have holes in them. I expect that others will rust through at any moment. Now would be a good time to r & r the block heater as well. I am not finding much info on the freeze plugs anywhere so if anyone can give me some tips, that would be great.

2) Glow plug controller doesn't seem to work so I'm going to go ahead and do the manual switch in the cab. It has 11g plugs in it so I'm shopping for some 60's. Let me know if you have a good source for these.

3) While starting, the starter made that crazy noise like it wasn't totally engaging on the ring gear some of the time. I'm hoping we can just shim the starter and that the ring gear is still intact.

4) One of the injector return lines has a pin hole, so we'll be replacing that. On the front of the engine on the driver's side, the line that goes from the injector back to the pump is leaking right where it connects to the metal line.

5) Previous owner reports that the auxillary tank on the passenger side does not work. He has replaced the switch on the cab and that didn't work. Must be the 6 port valve, so I'll need to look at that. This is also an area where I'm not finding much info so if anyone has any experience with that I would love to hear about it.

6) As previously reported, there is tons of gunk in the intake. Also, most of the vacuum hoses that connect the EGR are broken so I'm thinking a J intake is the solution.

7) Voltage guage doesn't work, but the alternator is charging.

8) Oil pressure guage was pegged over 80 so I don't know what to think about that. I suppose I should change the sending unit? Anyone have a good place to start on tracking this problem down?

Anyway...We are pleased with our project truck and are looking forward to bringing it back from the dead. We love love love our 6.2s. Any tips are appreciated!

Lewis

[john8662]

Nice weekend's worth of work!

For the starter, make sure that the front support brace and bolt that holds up the heavy end of the starter is in place. Otherwise, you'll break starter bolts and have the possibility of the starter moving during cranking.

For the cooling system, you're in for a real treat I'm guessing. The freeze plugs are not real easy to get to, so install Brass freeze plugs as a replacement. I'm guessing that the engine has had a low concentration of antifreeze run through it throughout the years, leading to rust to form on the plugs. But, sometimes they rust from the outside in... Remember, two of the plugs are behind the engine mounts, so a lift will be required to remove the mounts to get at the plugs.

As for your gauges, check that the grounds are good on the engine and chassis. There will be two ground wires that mount to the back of the intake manifold on the passenger's side, make sure that they're present. One will be the flexible braided copper ground strap, the other a black #16 gauge wire. No good grounds equals goofy gauges.

The oil pressure gauge pegged past 80 is an open circuit to the sender, just check that the boot and wire to the sender is connected.

[CedarGrove]

So I replaced the freeze plugs that I could get to tonight...One on the drivers side near the oil filter and 2 behind the starter. There was tons of rusty gunk in the block when I pulled them out. Even found an old plug that someone had simply pushed into the block in one hole. Anyway...I replaced them with the rubber expansion kind and they seem to be doing okay. Ordered a new block heater from NAPA so I'll r&r that soon. Changed the oil filter, filled the rad with water, and fired it up. There were no leaks to begin with, but by the end of the night, the passenger side freeze plug under the motor mount had pretty much cut loose. Before that happened though, we took it out on the road and checked her out. The thing runs like a scalded dog. Did notice some heavy knocking at the higher revs just before shifting. Not sure what that's about. Seems to wait too long before shifting to the next gear all around...Always turning too many revs. I like to drive like an old man, keeping the revs down and poking along. Perhaps it was just the way I was driving it tonight though. The temp guage does work, although the oil pressure and volts meter are still broken. Good ground from cab to block and the boot and wire seemed to be connected to the sending unit. Bottom line is that I'm super pleased so far.

Need some tips on doing a thorough flushing of the cooling system.

I have a glow controller and return line renew kit coming from eBay. J intake coming from John. A new air filter waiting to be installed.

I'm going to start another thread to try to get some tips on r&r'ing freeze plugs under the motor mounts. BTW...I also have new motor mounts ready for that project.

Cheerio y'all,

Lewis

[CedarGrove]

So I replaced the C intake with a J this weekend and think that I've discovered where all of my greasy gunk in my intake is coming from. There are rubber boots on each end of the hard pipes that connect the CDR to the intake and 2 of mine were torn, allowing unfiltered air into the intake. Stopped by the dealer today to try to order some replacements and they are unavailable. Has anyone replumbed these pipes with something else before? I'm sure I'm not the only one who has been through this.

Lewis

[t rex 7]

The gunk in the intake is completly normal for an EGR 6.2. The light duty 6.2's had the EGR valve that allowed exhaust gasses (sut) into the intake. The intake is already breathing oil from the CDR (Crankcase Depression Regulator, think BIG PCV), but with oil the sut sticks.. The Best upgrade is to not clean the one you have, but to upgrade to the HD series intake. This will remove the EGR function and actually lead to a cleaner burning engine, with the capacity of taking in more air and a little better performance.


Thanks also for the info about the intake, I thought that was normal also for my 84 C10. Looks like I will have to get that manifold changed when I get some time.

t rex

[BMOW]

If you are still looking for 60's I ordered a set from US Diesel yesterday for $11 a piece. Found a set for a little cheaper on another site but had no knowledge about the company. Good things are said about US Diesel on TDP so I ordered from them. Seemed friendly and knowledgeable on the phone.