2002 carbon on valves+other question

I started taking my 2002 apart to clean up the engine room. Once the intake manifold was off I could see some valves. They look quite gummed up with carbon.



As I recall I did a compression test when I got the car and it was OK. MAybe I don't remember and didn't do it.
Just wondering if this looks like normal deposits and would a remedy like Motorvac or Sea Foam be useful once the car is buttoned up and hopefully running again.
Hoping to have it running by mid November .

Second question:

Were the intake Manifolds on a 72' 2002 painted at the factory or were they bare aluminum? After giving mine a rough degreasing, it appears the manifold is painted and still in decent shape. My gut feeling is that this is the first time this part is off the car and there is no overspray on the fittings.



Digging under the gunk that the original owner kept applying (Apparently a mixture of solvents and gun oil) I think I might have perhaps the least rusty original 72' 2002 that could have lived in Ontario all these years (Still has rust….just not that much)



A lot more grease to come off.

Don't think manifolds were painted, just a rough casting. Best to tumble and clear ceramic coat. If you sand blast be prepared to scrub with wood handle wire brush to remove all the sand.

Nicad said:

I started taking my 2002 apart to clean up the engine room. Once the intake manifold was off I could see some valves. They look quite gummed up with carbon.



As I recall I did a compression test when I got the car and it was OK. MAybe I don't remember and didn't do it.
Just wondering if this looks like normal deposits and would a remedy like Motorvac or Sea Foam be useful once the car is buttoned up and hopefully running again.
Hoping to have it running by mid November .

Click to expand...

"Normal" is a relative term. Looks not abnormal to me.

Much depends upon miles since valve job, fuel type and - where you might be directing the valve cover blowby. I have no personal experience with it, but you could always try blasting with walnut shell fragments. BMW manual: https://www.minitechinfo.com/tsb/attachments/M040311_Carbon_Blaster_Operating_Manual.pdf

Read here:http://www.e90post.com/forums/showthread.php?t=682116


http://www.youtube.com/watch?v=ONp6gQXpyKU

2002 carbon

Hi,

The intakes are just bare aluminum, that's all. As far as the deposit on the valves, it really depends on the mileage, type of oil, compression. A lot of these old single barrel carbs had more carbon than the later ones with the 2 barrel.

I kinda liked the single barrel, simple, decent gas mileage and enough power if you are not a speed freak. Certainly haven't worked on one for a while, don't see that many. I would see if you could get some of iy out and try a chemical in the fuel system, just be careful you don't dislodge a piece of carbon and get it stuck between the valve and seat.

You are lucky that there is little rust, I've worked on a few cars from back east, all were rusty and nothing but headaches. Good luck with your project.

Thanks, Rick

Thanks for the replies. Very interesting that walnut blasting. I'd love to rent that tool. Wonder if there is a Chinese clone version?
650 Euros is probably the cost to have the head rebuilt. I'll look into the tumbling and ceramic coating locally or might just bead blast and treat with Alodine. …or keep cleaning and leave as is.

One side of me is tempted to modify this car with standard 2002 bolt on's, the other to not disturb it.

That is some serious gunk. I hesitate doing anything in situ - looks like years of over rich mix or serious oil ring fatigue. Get it running like you say and then decide if it's just the head that needs work or the total engine job.

If your car is "original" (matching numbers motor etc) or close to it and in as good condition as it appears then I would keep it that way (I can't believe I said that) and get it into as good running operation as possible and limit any mods to things like petronix instead of points.

This is not what I have done with mine but mine was already messed with so there was no going back. I've sat in pristine original and highly modified and mine is in-between but the original was more authentic and just more fun.

I can't believe I'm saying this.

Nicad said:

Thanks for the replies. Very interesting that walnut blasting. I'd love to rent that tool. Wonder if there is a Chinese clone version?
650 Euros is probably the cost to have the head rebuilt.

Click to expand...

Walnut decoking is primarily employed for direct injection situations where the intake valves and surrounds are not exposed to fuel, so that methanol/toluene treatments are impractical. That is not the case with M10 and M30 engines, circa '60s-'70s. I haven't needed to check for deposits in many years, but it was usually easier to try fuel additives, as you suggest, and eventually pull the head for hot tanking and a valve job. Of course that generally entailed resurfacing the head and the expense of valve gear disassembly.

I am not aware of any simple carbon removal methods without some drawbacks, be they cost or potential damage. Additives seem relatively benign but their effectivness is debatable. Likewise, although unlikely, they are capable of unleashing material that doesn't always make cylinder walls and piston rings happy. The walnut blasting seems promising enough, and there are some DIY guides available, that seem to make the process somewhat economically appealing. http://blog.bavauto.com/15543/ http://www.e90post.com/forums/attachment.php?attachmentid=949053&d=1386280979 I read somewhere about using dry ice as a blasting media that "allegedly" leaves no residue, and might not even require valves being closed during the blasting procedure. If this sounds too good to be true, so does obtaining music and pictures without wires.

I would think you'd still want the valves closed for the dry ice to keep chunks of carbon from getting in there, but it does sound much less messy than walnut.

If it is really a concern, with all the effort of blasting, in the end it's probably better to pull the head and have it gone through, and have it come back all nice and clean and in spec. I can't see getting all of the carbon in the tight spots off while still in place.

And work on the problem as to what is causing all that gunk - too rich or leaky rings etc. as mentioned.

Or maybe just an Italian tune up - put some treatment in the gas and drive it on the highway for a couple hundred miles...

We've generally stopped using walnut shells for cleaning gas turbines because we've found they will clog up the air cooling holes in the turbine blades. Those are pretty small holes and I would guess they would be on the same order of any "hole" or defect between the valve and the valve seat. Do you still have good compression? I might be concerned about getting walnut dust into the cylinder and around the ring area.

If it looks that bad and you have the head off, why not just do a valve job? I can see using the walnuts in a modern, V-8/V-12 direct injection engine but how hard is it to pull the head of an M10?

Interesting options with the dry ice and Blaster rental (thanks Lloyd)

I think I will follow Doug's advice , bolt it together and see what I got. Taking it apart is pretty easy should I need to go round two. On a previous car I owned (1995 Subaru Legacy 2.2) a Motorvac service transformed the car. It had about 100,000 miles on it at the time, was driven sedately by a priest (or flogged) and was completely constipated.
After Motorvac it revved to redline and ran great till I sold it with 200K.

The service I have used recently on my current Forester Turbo with (90,000 miles) is called Terra Clean

http://www.terraclean.net/app_guide2/index.php

Can't say I noticed a difference.

decoupe said:

That is some serious gunk. I hesitate doing anything in situ - looks like years of over rich mix or serious oil ring fatigue. Get it running like you say and then decide if it's just the head that needs work or the total engine job.

If your car is "original" (matching numbers motor etc) or close to it and in as good condition as it appears then I would keep it that way (I can't believe I said that) and get it into as good running operation as possible and limit any mods to things like petronix instead of points.

This is not what I have done with mine but mine was already messed with so there was no going back. I've sat in pristine original and highly modified and mine is in-between but the original was more authentic and just more fun.

I can't believe I'm saying this.

Click to expand...

Yes this the only car I have owned where modding it seems wrong. I even have the original owners notes and records and some of his tools. He was apparently quite a funny guy, owned a Jag but loved this 2002 till he passed away. The guy I bought it off of was his neighbour and he said he would be under it each weekend applying his gunk mixture. I am hoping to get it moved and stored in a very dry location I have rented.

The manifold is not painted after all. Kinda looked like Alumablast, but with my glasses on and another degreasing, this is the bare aluminum. Surprising that it did not get ugly like the aluminum on my daily car after two Canadian winters.