Help ME!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Marck]

First time resealing my engine.

I removed the cylinder heads last weekend, then cleaned the head gasket area on the block. The cylinder walls were already very clean and could still see a crosshatch. I am in college so I could only work the weekends on this engine. So I oiled the two exposed cylinder walls with some MMO and stick a clean rag in each cylinder to keep dirt out. I come back to the engine today to continue working on my engine, and I am shocked to find that one of the clean cylinders got messed up. There is black stuff growing on the cylinder wall. I don't know what it is or how to remove it. Is it corrosion or a biofilm? Now what do I do? How can I clean it off? Am I going to have take the block to a machine shop? I already poured a lot of money into this engine and I don't know what to do. The block was a low mileage engine (like 60 or 70 thousand miles). And I wasn't planning on rebuilding it. I was just going to replace a cracked head.

 

BTW, the other cylinder was spotlist just like I left it.

 

I already stuck some more MMO on the black stuff and even some carb cleaner and it seems that the top layer of this sh*t wiped off onto my rag. But how do I remove the rest?

 

I need suggestions immediately please. I am freaking out here!!!!!!!!!!!!!!

[Marck]

I have been trying to wipe the remaining off using MMO and a rag and it won't come off. It kind of leaves a orange looking rust stain on the rag. I think it may be rust. I have no garage, so the engine sits outside with a tarp keeping it covered. I can't believe rust comes and spreads that quickly. It looks bad and it is almost all the way around the cylinder. It is rough even though wipe it may have smoothened it out a bit. If it is rust, is it okay to rebuild the engine in this condition? Will the piston moving up and down wear this stuff away? Is this commone with engine teardowns?

[Nug]

Rust is really abrasive. While the engine would certainly run, and the rings would remove it in seconds, it does nothing for the life of the engine.

 

The correct thing to do would be to disassemble the engine, hone the rust out, clean, and reassemble. What you actually do you can take to the grave, if you don't want to admit it. The engine will run either way.

[Craven]

What is MMO? Duh I got it.

[oddcomp]

well you could also go get a cheap "bottle brush" type of hone witht he small balls on it

and and run it in the cylinder a few times .. yes with the piston in it

clea the walls very well and then turn the motor over by hand slowly so the rings will scrape teh missed stuff up and deposit it at teh top of the stroke and then rotate far enough to pull the pistons back intot he bottom of the bore

wipe clean again and oil

[worknwood]

I just went through a similar situation with an '88 RX that had been sitting with the head off. Rust will develope quite fast in humid conditions (Calif. this winter). You may have missed the affected area when you oiled the cylinder wall, or your rag may have been moist. You will have to use an abrasive of some type, while using an approach what will contain the abrasive particles as much as posible. If you have not turned the engine yet, don't until you git rid of the rust, it is very abrasive and will scrath your rings. I used an engine stand and turned the cylinder downward, sprayed the rust with WD40 to lubricate and used emery cloth (medium/fine) to remove the rust by hand. I then used a clean cloth saturate with sovent to clean the area, turning the cloth until it came out clean. Work as close to the top of the piston as you can. Spray rainse and wipe the entire exsposed cylinder several times with WD40. I wouldn't use carb. cleaner here, it will wash the cylinder of all oil and invite more rust. If you have clearance, move the piston to the bottom of the cylinder and check to see if its top was covering any more rust and Repeat removal if any. The rust shouldn't be to deep for the time you left it, and this should work for you. MMO the cylinder good and again before assymbly, and change break-in oil early in case a little bit of grit got missed.

 

MMO is Marvel Mystery Oil, great for assymbly and break-in, red can with black and white lettering. Can be found in most specialty oil sections.

[Marck]

Thanks for the quick replies. I called the machine shop that I sent my heads to to also see what he recommended and he gave me similar advice. He said to squirt some WD-40 in the cylinder and to scrub the rust with a scotch bright pad. That removed most of it and made the cylinder smooth again. He said what ever rust is left will go away when I run the car again. I was really worried every one was going to tell me to tear the block apart and have the cylinders honed.

 

I learned a few lessons from this:

1. Squirt oil or WD-40 in exposed cylinders daily especially if engine is kept outside.

2. Honing is only required when installing new piston rings because the cross hatch that is caused by honing is only needed to get oil to the top of the clyinder to help break in the rings. Once rings are broken in, the cross hatch is no longer needed and usually wears away later down the road.

[archemitis]

wd40 wont cling well enough.

 

engine oil is the thing to use...

 

whenever an engine sits for an extended period of time, the rings rust to the cylinder sleeve. start it up, and it shaves it all off.... not good for the engine, but not uncommon.

[Craven]

I've been thinking about this.(I know, not a good thing).

 

Now if you park a car outside and not run or turn over the engine for quite some time. Wouldn't the same thing happen, being that some of the valves would be open to let the outside air into the one or more of the cylinders?

[Marck]

wd40 wont cling well enough.

 

engine oil is the thing to use...

 

whenever an engine sits for an extended period of time, the rings rust to the cylinder sleeve. start it up, and it shaves it all off.... not good for the engine, but not uncommon.

 

Thanks for the tip. I'll squirt motor oil instead and I'll turn the motor daily. It will be sitting for 3 weeks until I have the time to reassemble .

[Craven]

Thanks for the tip. I'll squirt motor oil instead and I'll turn the motor daily. It will be sitting for 3 weeks until I have the time to reassemble .

Or a thin film grease and not roll it over until you put it back togeather. Then roll each piston up and wipe off the grease.